We carry out an analysis of the full set of ten B¯→D(∗) form factors within the framework of the Heavy-Quark Expansion (HQE) to order (αs,1/mb,1/m2c), both with and without the use of experimental data. This becomes possible due to a recent calculation of these form factors at and beyond the maximal physical recoil using QCD light-cone sum rules, in combination with constraints from lattice QCD, QCD three-point sum rules and unitarity. We find good agreement amongst the various theoretical results, as well as between the theoretical results and the kinematical distributions in B¯→D(∗){e−,μ−}ν¯ measurements. The coefficients entering at the 1/m2c level are found to be of (1), indicating convergence of the HQE. The phenomenological implications of our study include an updated exclusive determination of |Vcb| in the HQE, which is compatible with both the exclusive determination using the BGL parametrization and with the inclusive determination. We also revisit predictions for the lepton-flavour universality ratios RD(∗), the τ polarization observables PD(∗)τ, and the longitudinal polarization fraction FL. Posterior samples for the HQE parameters are provided as ancillary files, allowing for their use in subsequent studies.

Parametric correlations are studied in several classes of covariant density functional theories (CDFTs) using a statistical analysis in a large parameter hyperspace. In the present manuscript, we investigate such correlations for two specific types of models, namely, for models with density dependent meson exchange and for point coupling models. Combined with the results obtained previously in Ref. [1] for a non-linear meson exchange model, these results indicate that parametric correlations exist in all major classes of CDFTs when the functionals are fitted to the ground state properties of finite nuclei and to nuclear matter properties. In particular, for the density dependence in the isoscalar channel only one parameter is really independent. Accounting for these facts potentially allows one to reduce the number of free parameters considerably.

Single-particle resonances are crucial for exotic nuclei near and beyond the drip lines. Since the majority of nuclei are deformed, the interplay between deformation and orbital structure near threshold becomes very important and can lead to an improved description of exotic nuclei. In this work, the Green's function (GF) method is applied to solve the coupled-channel Dirac equation with quadrupole-deformed Woods-Saxon potentials. The detailed formalism for the partial-wave expansion of the Green's function is presented. A different approach getting exact values for energies and widths of resonant states by the GF method is proposed. Numerical checks are carried out by comparing with our previous implementation of the spherical GF method and the results from the deformed complex momentum representation, the analytical continuation of the coupling constant, and the scattering phase shift methods, and it is proved that the GF method is very effective and reliable for describing resonance states, no matter whether they are narrow or broad, spherical or deformed. Finally, Nilsson levels for bound and resonant orbitals in the halo candidate nucleus 37Mg are calculated from the deformed GF method over a wide range of deformations, and some decisive hints of p-wave halo formation are shown in this nucleus; namely, the crossing between the configurations 1/2[321] and 5/2[312] at deformation parameter β>0.5 may enhance the probability to occupy the 1/2[321] orbital that originates from the 2p3/2 shell.

Direct imaging is a tried and tested method of detecting exoplanets in the near infrared, but has so far not been extended to longer wavelengths. New data at mid-IR wavelengths (8-20{\mu}m) canprovide additional constraints on planetary atmospheric models. We use the VISIR instrumenton the VLT to detect or set stringent limits on the 8.7{\mu}m flux of the four planets surrounding HR8799, and to search for additional companions. We use a novel circularised PSF subtractiontechnique to reduce the stellar signal and obtain instrument limited background levels andobtain optimal flux limits. The BT SETTL isochrones are then used to determine the resultingmass limits. We find flux limits between 0.7 and 3.3 mJy for the J8.9 flux of the differentplanets at better than5{\sigma}level and derive a new mass limit of 30 MJupfor any objects beyond40 AU. While this work has not detected planets in the HR 8799 system at 8.7{\mu}m, it has foundthat an instrument with the sensitivity of VISIR is sufficient to detect at least 4 known hotplanets around close stars, including\b{eta}Pictoris b (1700 K, 19 pc), with more than5{\sigma}certaintyin 10 hours of observing time in the mid-IR.

The (tree) amplituhedron A(n,k,m) is the image in the Grassmannian Gr(k,k+m) of the totally nonnegative part of Gr(k,n), under a (map induced by a) linear map which is totally positive. It was introduced by Arkani-Hamed and Trnka in 2013 in order to give a geometric basis for the computation of scattering amplitudes in N=4 supersymmetric Yang-Mills theory. In the case relevant to physics (m=4), there is a collection of recursively-defined 4k-dimensional BCFW cells in the totally nonnegative part of Gr(k,n), whose images conjecturally "triangulate" the amplituhedron--that is, their images are disjoint and cover a dense subset of A(n,k,4). In this paper, we approach this problem by first giving an explicit (as opposed to recursive) description of the BCFW cells. We then develop sign-variational tools which we use to prove that when k=2, the images of these cells are disjoint in A(n,k,4). We also conjecture that for arbitrary even m, there is a decomposition of the amplituhedron A(n,k,m) involving precisely M(k, n-k-m, m/2) top-dimensional cells (of dimension km), where M(a,b,c) is the number of plane partitions contained in an a x b x c box. This agrees with the fact that when m=4, the number of BCFW cells is the Narayana number N(n-3, k+1).

Deformed relativistic kinematics, expected to emerge in a flat-spacetime limit of quantum gravity, predicts violation of discrete symmetries at energy scale in the vicinity of the Planck mass. Momentum-dependent deformations of the C, P and T invariance are derived from the \k{appa}-deformed Poincaré algebra. Deformation of the CPT symmetry leads to a subtle violation of Lorentz symmetry. This entails some small but measurable phenomenological consequences, as corrections to characteristics of time evolution: particle lifetimes or frequency of flavour oscillations in two-particle states at high energy. We argue here that using current experimental precisions on the muon lifetime one can bound the deformation parameter \k{appa} > 10^14 GeV at LHC energy and move this limit even to 10^16 GeV at Future Circular Collider, planned at CERN. Weaker limits on deformation can be also obtained from interference of neutral mesons. In case of B0s from {\Upsilon} decay it amounts to \k{appa} > 10^8 GeV at confidence level 99%.

The structure and morphology of supernova remnants (SNRs) reflect the properties of the parent supernovae (SNe) and the characteristics of the inhomogeneous environments through which the remnants expand. Linking the morphology of SNRs to anisotropies developed in their parent SNe can be essential to obtain key information on many aspects of the explosion processes associated with SNe. Nowadays, our capability to study the SN-SNR connection has been largely improved thanks to multi-dimensional models describing the long-term evolution from the SN to the SNR as well as to observational data of growing quality and quantity across the electromagnetic spectrum which allow to constrain the models. Here we used the numerical resources obtained in the framework of the ``Accordo Quadro INAF-CINECA (2017)'' together with a CINECA ISCRA Award N.HP10BARP6Y to describe the full evolution of a SNR from the core-collapse to the full-fledged SNR at the age of 2000 years. Our simulations were compared with observations of SNR Cassiopeia A (Cas A) at the age of ∼ 350 years. Thanks to these simulations we were able to link the physical, chemical and morphological properties of a SNR to the physical processes governing the complex phases of the SN explosion.

The measurement of an astrophysical flux of high-energy neutrinos by IceCube is an important step towards finding the long-sought sources of cosmic rays. Nevertheless, the long exposure neutrino sky map shows no significant indication of point sources so far. This may point to a large population of faint, steady sources or flaring objects as origins of this flux. The most compelling evidence for a neutrino point source so far is the recent observation of the flaring gamma-ray blazar TXS 0506+056 in coincidence with a high-energy neutrino from IceCube. This is a result of a Neutrino Target of Opportunity (NToO) program in which all currently operating Imaging Atmospheric Cherenkov Telescopes (IACTs) take part. The case for TXS 0506+056 being a neutrino source was made stronger by evidence of a 5-month long neutrino flare in 2014-2015.Here we investigate the chances of a detection of a gamma-ray counterpart to a neutrino source with CTA, as a result of a follow-up observation of a neutrino alert. We use the FIRESONG software to simulate different neutrino sources populations, which could be responsible for the diffuse flux of astrophysical neutrinos as measured by IceCube. We scan over parameters that can be used to describe the populations such as density (density rate) for steady (flaring) objects. Several CTA array layouts and instrument response functions are tested in order to derive optimal follow-up strategies and the potential science reach of the NToO program for CTA. We find that following neutrino alerts by IceCube, CTA has a low per alert probability of detecting a matching steady source. However, using a model by Halzen et al. (2018), for neutrino flares similar to that of 2014-2015, we find that CTA will detect a counterpart in as many as one third of the alerts.

The large volume of data expected to be produced by the Belle II experiment presents the opportunity for studies of rare, previously inaccessible processes. Investigating such rare processes in a high data volume environment necessitates a correspondingly high volume of Monte Carlo simulations to prepare analyses and gain a deep understanding of the contributing physics processes to each individual study. This resulting challenge, in terms of computing resource requirements, calls for more intelligent methods of simulation, in particular for processes with very high background rejection rates. This work presents a method of predicting in the early stages of the simulation process the likelihood of relevancy of an individual event to the target study using graph neural networks. The results show a robust training that is integrated natively into the existing Belle II analysis software framework.

Numerically estimating the integral of functions in high dimensional spaces is a non-trivial task. A oft-encountered example is the calculation of the marginal likelihood in Bayesian inference, in a context where a sampling algorithm such as a Markov Chain Monte Carlo provides samples of the function. We present an Adaptive Harmonic Mean Integration (AHMI) algorithm. Given samples drawn according to a probability distribution proportional to the function, the algorithm will estimate the integral of the function and the uncertainty of the estimate by applying a harmonic mean estimator to adaptively chosen regions of the parameter space. We describe the algorithm and its mathematical properties, and report the results using it on multiple test cases.

Recent years have seen considerable progress with ab-initio calculations of the

nuclear structure by non-relativistic many-body methods. Dirac-Brueckner-Hartree-Fock

Theory provides a relativistic ab-intio approach, which is able to reproduce saturation properties

of symmetric nuclear matter without three-body forces. However, so far, the corresponding

equations have been solved only for positive energy states. Negative energy states have

been included for forty years in various approximations, leading to differences in the isospin

dependence. This problem has been solved only recently by a complete solution of the self-

consistent relativistic Brueckner-Hartree-Fock equations in asymmetric nuclear matter. Due

to its numerical complexity, however, it is very difficult to extend the Relativistic Brueckner-

Hartree-Fock theory to the study of finite nuclear systems. Recent efforts will be discussed to

overcome this problem.

The time dependent density functional theory is applied to study modes of vibrational excitations in atomic nuclei. The covariant density functional DD-ME2 is adopted. It turns out that DD-ME2 is able to provide simultaneously a satisfactory description of isocalar giant monopole (ISGM), isovector giant dipole (IVGD), and isoscalar giant quadrupole (ISGQ) resonances. The functional is also able to describe very well the soft dipole modes known as pygmy dipole resonances (PDR).

In an interacting neutrino gas, flavor coherence becomes dynamical and can propagate as a collective mode. In particular, tachyonic instabilities can appear, leading to "fast flavor conversion" that is independent of neutrino masses and mixing angles. On the other hand, without neutrino-neutrino interaction, a prepared wave packet of flavor coherence simply dissipates by kinematical decoherence of infinitely many non-collective modes. We reexamine the dispersion relation for fast flavor modes and show that for any wavenumber, there exists a continuum of non-collective modes besides a few discrete collective ones. So for any initial wave packet, both decoherence and collective motion occurs, although the latter typically dominates for a sufficiently dense gas. We derive explicit eigenfunctions for both collective and non-collective modes. If the angular mode distribution of electron-lepton number crosses between positive and negative values, two non-collective modes can merge to become a tachyonic collective mode. We explicitly calculate the interaction strength for this critical point. As a corollary we find that a single crossing always leads to a tachyonic instability. For an even number of crossings, no instability needs to occur.

This thesis seeks to identify and investigate various universal quantum phenomena that are particularly, albeit by far not exclusively, relevant for gravity. In the first part, we study the question of how long a generic quantum system can be approximated as classical. Using a prototypical model of a self-interacting scalar field, we discuss possible scalings of the quantum break-time, after which the classical description breaks down. Subsequently, we apply this analysis to the hypothetical QCD axion. We conclude that the approximation as classically oscillating scalar field is extremely accurate. Next we turn to de Sitter. Our approach is to resolve the classical metric as a multi-graviton state defined on top of Minkowski vacuum. On the one hand, this composite picture of de Sitter is able to reproduce all known (semi)classical properties. On the other hand, it leads a breakdown of the description in terms of a classical metric after the timescale 1/(G H^3), where G and H correspond to Newton’s constant and the Hubble scale, respectively. This finding results in important restrictions on inflationary scenarios. [...]

The location at which life emerged on Earth defined the physical boundary conditions under which the first replicating systems evolved. Nonequilibrium systems were necessary to provide the energy driving these processes. One such nonequilibrium system could have been temperature gradients, found for example across porous rock in hydrothermal vents. The work presented here focuses on the effects of temperature gradients on molecules in these water-filled micro-compartments and on methods how they could be analyzed. [...]

Unilamellar lipid vesicles can serve as model for protocells. We present a vesicle fission mechanism in a thermal gradient under flow in a convection chamber, where vesicles cycle cold and hot regions periodically. Crucial to obtain fission of the vesicles in this scenario is a temperature-induced membrane phase transition that vesicles experience multiple times. We model the temperature gradient of the chamber with a capillary to study single vesicles on their way through the temperature gradient in an external field of shear forces. Starting in the gel-like phase the spherical vesicles are heated above their main melting temperature resulting in a dumbbell-deformation. Further downstream a temperature drop below the transition temperature induces splitting of the vesicles without further physical or chemical intervention. This mechanism also holds for less cooperative systems, as shown here for a lipid alloy with a broad transition temperature width of 8 K. We find a critical tether length that can be understood from the transition width and the locally applied temperature gradient. This combination of a temperature-induced membrane phase transition and realistic flow scenarios as given e.g. in a white smoker enable a fission mechanism that can contribute to the understanding of more advanced protocell cycles.

We revisit the decay Λ0b→Λ+cℓ−ν¯ (ℓ=e,μ,τ) with a subsequent two-body decay Λ+c→Λ0π+ in the Standard Model and in generic New Physics models. The decay's joint four-differential angular distribution can be expressed in terms of ten angular observables, assuming negligible polarization of the initial Λb state. We present compact analytical results for all angular observables, which enables us to discuss their possible New Physics reach. We find that the decay at hand probes more and complementary independent combinations of Wilson coefficients compared to its mesonic counter parts B¯→D(∗)ℓ−ν¯. Our result for the angular distribution is at variance with some of the results on scalar-vector interference terms in the literature. We provide numerical estimates for all angular observables based on lattice-QCD results for the Λb→Λc form factors and account for a recent measurement of the parity-violating parameter in Λ+c→Λ0π+ decays by BESIII. A numerical implementation of our results is made publicly available as part of the EOS software.

We present an alternative method for carrying out a principal-component analysis of Wilson coefficients in standard model effective field theory (SMEFT). The method is based on singular-value decomposition (SVD). The SVD method provides information about the sensitivity of experimental observables to physics beyond the standard model that is not accessible in the Fisher-information method. In principle, the SVD method can also have computational advantages over diagonalization of the Fisher information matrix. We demonstrate the SVD method by applying it to the dimension-6 coefficients for the process of top-quark decay to a b quark and a W boson and use this example to illustrate some pitfalls in widely used fitting procedures. We also outline an iterative procedure for applying the SVD method to dimension-8 SMEFT coefficients.

Context. Large area catalogs of galaxy clusters constructed from ROSAT All-Sky Survey provide the basis for our knowledge of the population of clusters thanks to long-term multiwavelength efforts to follow up observations of these clusters.Aims. The advent of large area photometric surveys superseding previous, in-depth all-sky data allows us to revisit the construction of X-ray cluster catalogs, extending the study to lower cluster masses and higher redshifts and providing modeling of the selection function.Methods. We performed a wavelet detection of X-ray sources and made extensive simulations of the detection of clusters in the RASS data. We assigned an optical richness to each of the 24 788 detected X-ray sources in the 10 382 square degrees of the Baryon Oscillation Spectroscopic Survey area using red sequence cluster finder redMaPPer version 5.2 run on Sloan Digital Sky Survey photometry. We named this survey COnstrain Dark Energy with X-ray (CODEX) clusters.Results. We show that there is no obvious separation of sources on galaxy clusters and active galactic nuclei (AGN) based on the distribution of systems on their richness. This is a combination of an increasing number of galaxy groups and their selection via the identification of X-ray sources either by chance or by groups hosting an AGN. To clean the sample, we use a cut on the optical richness at the level corresponding to the 10% completeness of the survey and include it in the modeling of the cluster selection function. We present the X-ray catalog extending to a redshift of 0.6.Conclusions. The CODEX suvey is the first large area X-ray selected catalog of northern clusters reaching fluxes of 10−13 ergs s−1 cm−2. We provide modeling of the sample selection and discuss the redshift evolution of the high end of the X-ray luminosity function (XLF). Our results on z <  0.3 XLF agree with previous studies, while we provide new constraints on the 0.3 <  z <  0.6 XLF. We find a lack of strong redshift evolution of the XLF, provide exact modeling of the effect of low number statistics and AGN contamination, and present the resulting constraints on the flat ΛCDM.Key words: surveys / catalogs / large-scale structure of Universe⋆ The catalog of clusters is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/638/A114

The light-meson spectrum can be studied by analyzing data from diffractive dissociation of pion or kaon beams. The contributions of the various states that are produced in these reactions are disentangled by the means of partial-wave analysis. A challenge in these analyses is that the partial-wave expansion has to be truncated, i.e. that only a finite subset of the infinitely many partial-wave amplitudes can be inferred from the data. In recent years, different groups have applied regularization techniques in order to determine the contributing waves from the data. However, to obtain meaningful results the choice of the regularization term is crucial. We present our recent developments of wave-selection methods for partial-wave analyses based on simulated data for diffractively produced three-pion events.

Context. Analyzing the properties of dust and its evolution in the early phases of star formation is crucial to put constraints on the collapse and accretion processes as well as on the pristine properties of planet-forming seeds.
Aims: In this paper, we aim to investigate the variations of the dust grain size in the envelopes of the youngest protostars.
Methods: We analyzed Plateau de Bure interferometric observations at 1.3 and 3.2 mm for 12 Class 0 protostars obtained as part of the CALYPSO survey. We performed our analysis in the visibility domain and derived dust emissivity index (β_1-3mm) profiles as a function of the envelope radius at 200-2000 au scales.
Results: Most of the protostellar envelopes show low dust emissivity indices decreasing toward the central regions. The decreasing trend remains after correction of the (potentially optically thick) central region emission, with surprisingly low β_1-3mm < 1 values across most of the envelope radii of NGC 1333-IRAS 4A, NGC 1333-IRAS 4B, SVS13B, and Serpens-SMM4.
Conclusions: We discuss the various processes that could explain such low and varying dust emissivity indices at envelope radii 200-2000 au. Our observations of extremely low dust emissivity indices could trace the presence of large (millimeter-size) grains in Class 0 envelopes, in which case our results would point to a radial increase of the dust grain size toward the inner envelope regions. While it is expected that large grains in young protostellar envelopes could be built via grain growth and coagulation, we stress that the typical timescales required to build millimeter grains in current coagulation models are at odds with the youth of our Class 0 protostars. Additional variations in the dust composition could also partly contribute to the low β_1-3mm we observe. We find that the steepness of the β_1-3mm radial gradient depends strongly on the envelope mass, which might favor a scenario in which large grains are built in high-density protostellar disks and transported to the intermediate envelope radii, for example with the help of outflows and winds.

We study the impact of anomalous couplings in the Higgs sector on the shape of the Higgs boson pair invariant mass distribution at NLO. Our analysis is based on a five-dimensional coupling parameter space relevant for Higgs boson pair production in gluon fusion, in the framework of a non-linear Effective Field Theory. In particular, we present a clustering procedure into certain shape types based on unsupervised machine learning, with the aim to infer information about the underlying parameter space from a given shape type.

We report the discovery of 10 kpc [C II] 158 μm halos surrounding star-forming galaxies in the early universe. We choose deep Atacama Large Millimeter/submillimeter Array data for 18 galaxies, each with a star formation rate of ≃10-70 M _⊙ with no signature of an active galactic nucleus whose [C II] lines are individually detected at z = 5.153-7.142, and we conduct stacking of the [C II] lines and dust continuum in the uv-visibility plane. The radial profiles of the surface brightnesses show a 10 kpc scale [C II] halo at the 9.2σ level, significantly more extended than the Hubble Space Telescope stellar continuum data by a factor of ∼5 on the exponential-profile basis, as well as the dust continuum. We compare the radial profiles of [C II] and Lyα halos universally found in star-forming galaxies at this epoch, and we find that the scale lengths agree within the 1σ level. While two independent hydrodynamic zoom-in simulations match the dust and stellar continuum properties, the simulations cannot reproduce the extended [C II] line emission. The existence of the extended [C II] halo is evidence of outflow remnants in the early galaxies and suggests that the outflows may be dominated by cold-mode outflows expelling the neutral gas.

We developed methods for mapping spatial variations of the spatial power spectrum (SPS) and structure function slopes, with the goal of connecting the statistical properties of neutral hydrogen (H I) with the turbulent drivers. The new methods were applied to the H I observations of the Small and Large Magellanic Clouds (SMC and LMC). In the case of the SMC, we find highly uniform turbulent properties of H I, with no evidence for local enhancements of turbulence due to stellar feedback. These properties could be caused by a significant turbulent driving on large scales. Alternatively, the significant line-of-sight depth of the SMC could be masking out localized regions with a steeper SPS slope caused by stellar feedback. In contrast to the SMC, the LMC H I shows a large diversity in terms of its turbulent properties. Across most of the LMC, the small-scale SPS slope is steeper than the large-scale slope due to the presence of the H I disk. On small spatial scales, we find several areas of localized steepening of the SPS slope around major H II regions, with the 30 Doradus region being the most prominent. This is in agreement with predictions from numerical simulations, which suggest a steepening of the SPS slope due to stellar feedback that erodes and destroys interstellar clouds. We also find a localized steepening of the large-scale SPS slope in the outskirts of the LMC. This is likely caused by the flaring of the H I disk, or alternatively, by ram-pressure stripping of the LMC disk due to the interactions with the surrounding halo gas.

We investigate the [C II] line intensity mapping (IM) signal from galaxies in the Epoch of Reionization (EoR) to assess its detectability, the possibility to constrain the L_{C II}-SFR relation, and to recover the [C II] luminosity function (LF) from future experiments. By empirically assuming that log L_{C II}=log A+γ SFR± σ _ L, we derive the [C II] LF from the observed UV LF, and the [C II] IM power spectrum. We study the shot noise and the full power spectrum separately. Although, in general, the shot-noise component has a much higher signal-to-noise ratio than the clustering one, it cannot be used to put independent constraints on log A and γ. Full power spectrum measurements are crucial to break such degeneracy and reconstruct the [C II] LF. In our fiducial survey S1 (inspired by CCAT-p/1000 h) at z ∼ 6, the shot-noise (clustering) signal is detectable for two (one) of the five considered L_{C II}-SFR relations. The shot noise is generally dominated by galaxies with L_{C II}≳ 10⁸-10⁹ L_⊙ (M_UV ∼ -20 to -22), already at reach of ALMA pointed observations. However, given the small field of view of such telescope, an IM experiment would provide unique information on the bright end of the LF. The detection depth of an IM experiment crucially depends on the (poorly constrained) L_{C II}-SFR relation in the EoR. If the L_{C II}-SFR relation varies in a wide log A-γ range, but still consistent with ALMA [C II] LF upper limits, even the signal from galaxies with L_{C II} as faint as ∼10⁷ L_⊙ could be detectable. Finally, we consider the contamination by continuum foregrounds (cosmic infrared background, dust, cosmic microwave background) and CO interloping lines, and derive the requirements on the residual contamination level to reliably extract the [C II] signal.

Dark matter substructure can contribute significantly to local dark matter searches and may provide a large uncertainty in the interpretation of those experiments. For direct detection experiments, sub-halos give rise to an additional dark matter component on top of the smooth dark matter distribution of the host halo. In the case of dark matter capture in the Sun, sub-halo encounters temporarily increase the number of captured particles. Even if the encounter happened in the past, the number of dark matter particles captured by the Sun can still be enhanced today compared to expectations from the host halo as those enhancements decay over time. Using results from an analytical model of the sub-halo population of a Milky Way-like galaxy, valid for sub-halo masses between 10^-5 M_solar and 10¹¹ M_solar, we assess the impact of sub-halos on direct dark matter searches in a probabilistic way. We find that the impact on direct detection can be sizable, with a probability of ~ 10^-3 to find an Script O(1) enhancement of the recoil rate. In the case of the capture rate in the Sun, we find that Script O(1) enhancements are very unlikely, with probability lesssim 10^-5, and are even impossible for some dark matter masses.

We present two determinations of the strong coupling α_s. The first one is from the static energy at three-loop accuracy, and may be considered an update of earlier determinations by some of us. The new analysis includes new lattice data at smaller lattice spacings, and reaches distances as short as 0.0237 fm. We present a comprehensive and detailed estimate of the error sources that contribute to the uncertainty of the final result, α_s(M_Z)=0.1166 0_-0.00056^+0.00110. The second determination is based on lattice data for the singlet free energy at finite temperature up to distances as small as 0.0081 fm, from which we obtain α_s(M_Z)=0.1163 8_-0.00087^{+0.0009 5}.

We calculate the step scaling function, the lattice analog of the renormalization group β -function, for an SU(3) gauge theory with twelve flavors. The gauge coupling of this system runs very slowly, which is reflected in a small step scaling function, making numerical simulations particularly challenging. We present a detailed analysis including the study of systematic effects of our extensive data set generated with twelve dynamical flavors using the Symanzik gauge action and three times stout smeared Möbius domain wall fermions. Using up to 32⁴ volumes, we calculate renormalized couplings for different gradient flow schemes and determine the step-scaling β function for a scale change s =2 on up to five different lattice volume pairs. Our preferred analysis is fully O (a²) Symanzik improved and uses Zeuthen flow combined with the Symanzik operator. We find an infrared fixed point within the range 5.2 ≤g_c²≤6.4 in the c =0.250 finite volume gradient flow scheme. We account for systematic effects by calculating the step-scaling function based on alternative flows (Wilson or Symanzik) as well as operators (Wilson plaquette, clover) and also explore the effects of the perturbative tree-level improvement.

The detection of the high-energy neutrino event, IceCube-170922A, demonstrated that multimessenger particle astrophysics triggered by neutrino alerts is feasible. We consider time delay signatures caused by secret neutrino interactions with the cosmic neutrino background and dark matter and suggest that these can be used as a novel probe of neutrino interactions beyond the standard model (BSM). The tests with BSM-induced neutrino echoes are distinct from existing constraints from the spectral modification and will be enabled by multimessenger observations of bright neutrino transients with future experiments such as IceCube-Gen2, KM3Net, and Hyper-Kamiokande. The constraints are complementary to those from accelerator and laboratory experiments and powerful for testing various particle models that explain tensions prevailing in the cosmological data.

The existence of millicharged dark matter (mDM) can leave a measurable imprint on 21-cm cosmology through mDM-baryon scattering. However, the minimal scenario is severely constrained by existing cosmological bounds on both the fraction of dark matter that can be millicharged and the mass of mDM particles. We point out that introducing a long-range force between a millicharged subcomponent of dark matter and the dominant cold dark matter (CDM) component leads to efficient cooling of baryons in the early Universe, while also significantly extending the range of viable mDM masses. Such a scenario can explain the anomalous absorption signal in the sky-averaged 21-cm spectrum observed by EDGES and leads to a number of testable predictions for the properties of the dark sector. The mDM mass can then lie between 10 MeV and a few hundreds of GeVs, and its scattering cross section with baryons lies within an unconstrained window of parameter space above direct detection limits and below current bounds from colliders. In this allowed region, mDM can make up as little as 10^-8 of the total dark matter energy density. The CDM mass ranges from 10 MeV to a few GeVs and has an interaction cross section with the Standard Model that is induced by a loop of mDM particles. This cross section is generically within reach of near-future low-threshold direct detection experiments.

Physics beyond the Standard Model can manifest itself as both new light states and heavy degrees of freedom. In this paper, we assume that the former comprise only a sterile neutrino, N . Therefore, the most agnostic description of the new physics is given by an effective field theory built upon the Standard Model fields as well as N . We show that Higgs phenomenology provides a sensitive and potentially crucial tool to constrain effective gauge interactions of sterile neutrinos, not yet probed by current experiments. In parallel, this motivates a range of new Higgs decay channels with clean signatures as candidates for the next LHC runs, including h →γ +p_T^miss and h →γ γ +p_T^miss .

We study charged Dirac quasinormal modes (QNMs) on Reissner-Nordström-anti-de Sitter (RN-AdS) black holes with generic Robin boundary conditions, by extending our earlier work of neutral Dirac QNMs on Schwarzschild-AdS black holes. We first derive the equations of motion for charged Dirac fields on a RN-AdS background. To solve these equations we impose a requirement on the Dirac field: that its energy flux should vanish at asymptotic infinity. A set of two Robin boundary conditions compatible with QNMs is consequently found. By employing both analytic and numeric methods, we then obtain the quasinormal spectrum for charged Dirac fields and analyze the impact of various parameters, in particular of electric charges. An analytic calculation shows explicitly that the charge coupling between the black hole and the Dirac field does not trigger super-radiant instabilities in the small black hole and low frequency limit. Numeric calculations, on the other hand, show quantitatively that Dirac QNMs may change substantially due to the electric charge. Our results illustrate how vanishing energy flux boundary conditions, as a generic principle, are applicable not only to neutral but also to electrically charged fields.

Consistency relations for the large scale structure are exact equalities between correlation functions of different order. These relations descend from the equivalence principle and hold for primordial perturbations generated by single-field models of inflation. They are not affected by nonlinearities and hold also for biased tracers and in redshift space. We show that baryonic acoustic oscillations in the bispectrum (BS) in the squeezed limit are suppressed with respect to those in the power spectrum by a coefficient that depends on the BS configuration and on the bias parameter (and, in redshift space, also on the growth rate). We test these relations using large volume N -body simulations and show that they provide a novel way to measure large scale halo bias and, potentially, the growth rate. Since bias is obtained by comparing two directly observable quantities, the method is free from theoretical uncertainties both on the computational scheme and on the underlying cosmological model.

By means of 3D hydrodynamical simulations, we evaluate here the impact that supernova (SN) explosions occurring within wind-driven bubbles have on the survival or destruction of dust grains. We consider both the dust generated within the ejecta and the dust initially present in the ambient gas and later locked up in the surrounding wind-driven shell (WDS). The collision of the SN blast wave with the WDS leads to a transmitted shock that moves into the shell and a reflected shock that moves into the ejecta. The transmitted shock is capable of destroying large amounts of the dust locked in the shell, but only if the mass of the WDS is small, less than a few tens the ejected mass. Conversely, massive WDSs, with several times the ejected mass, lead upon the interaction to strong radiative cooling, which inhibits the Sedov-Taylor phase and weakens the transmitted shock, making it unable to traverse the WDS. In such a case, the destruction/disruption of the ambient dust is largely inhibited. On the other hand, the SN remnants grow rapidly in the very tenuous region excavated by the stellar winds, and thus a large fraction of the dust generated within the ejecta is not efficiently destroyed by the SN reverse shock, nor by the reflected shock. Our calculations favor a scenario in which core-collapse SNe within sufficiently massive WDSs supply more dust to the interstellar medium than they are able to destroy.

We introduce k-evolution, a relativistic N-body code based on gevolution, which includes clustering dark energy among its cosmological components. To describe dark energy, we use the effective field theory approach. In particular, we focus on k-essence with a speed of sound much smaller than unity but we lay down the basis to extend the code to other dark energy and modified gravity models. We develop the formalism including dark energy non-linearities but, as a first step, we implement the equations in the code after dropping non-linear self-coupling in the k-essence field. In this simplified setup, we compare k-evolution simulations with those of CLASS and gevolution 1.2, showing the effect of dark matter and gravitational non-linearities on the power spectrum of dark matter, of dark energy and of the gravitational potential. Moreover, we compare k-evolution to Newtonian N-body simulations with back-scaled initial conditions and study how dark energy clustering affects massive halos.

We introduce a new technique to estimate the comet nuclear size frequency distribution (SFD) that combines a cometary activity model with a survey simulation and apply it to 150 long period comets (LPC) detected by the Pan-STARRS1 near-Earth object survey. The debiased LPC size-frequency distribution is in agreement with previous estimates for large comets with nuclear diameter ≳1 km but we measure a significant drop in the SFD slope for small objects with diameters <1 km and approaching only 100 m diameter. Large objects have a slope α_big = 0.72 ± 0.09(stat.) ± 0.15(sys.) while small objects behave as α_small = 0.07 ± 0.03(stat.) ± 0.09(sys.) where the SFD is ∝ 1^{0 αH_N} and H_N represents the cometary nuclear absolute magnitude. The total number of LPCs that are >1 km diameter and have perihelia q < 10 au is 0.46 ± 0.15 × 10⁹ while there are only 2.4 ± 0.5(stat.) ± 2(sys.) × 10⁹ objects with diameters >100 m due to the shallow slope of the SFD for diameters <1 km. We estimate that the total number of 'potentially active' objects with diameters ≥1 km in the Oort cloud, objects that would be defined as LPCs if their perihelia evolved to <10 au, is (1.5 ± 1) × 10¹² with a combined mass of 1.3 ± 0.9 M_⊕. The debiased LPC orbit distribution is broadly in agreement with expectations from contemporary dynamical models but there are discrepancies that could point towards a future ability to disentangle the relative importance of stellar perturbations and galactic tides in producing the LPC population.

We study the role of anisotropic escape in generating the elliptic flow of bottomonia produced in ultrarelativistic heavy-ion collisions. We implement temperature-dependent decay widths for the various bottomonium states to calculate their survival probability when traversing through the anisotropic hot medium formed in noncentral collisions. We employ the recently developed 3 +1 -dimensional quasiparticle anisotropic hydrodynamic simulation to model the space-time evolution of the quark-gluon plasma. We provide a quantitative prediction for the transverse momentum dependence of bottomonium elliptic flow and the nuclear modification factor for Pb +Pb collisions in √{s_NN}=2.76 TeV at the CERN Large Hadron Collider.

We discuss how LHC di-muon data collected to study $B_q \to \mu\mu$ can be used to constrain light particles with flavour-violating couplings to $b$-quarks. Focussing on the case of a flavoured QCD axion, $a$, we compute the decay rates for $B_q \to \mu \mu a$ and the SM background process $B_q \to \mu \mu \gamma$ near the kinematic endpoint. These rates depend on non-perturbative $B_q \to \gamma^{(*)}$ form factors with on- or off-shell photons. The off-shell form factors -- relevant for generic searches for beyond-the-SM particles -- are discussed in full generality and computed with QCD sum rules for the first time. With these results, we analyse available LHCb data to obtain the sensitivity on $B_q \to \mu \mu a$ at present and future runs. We find that the full LHCb dataset alone will allow to probe axion-coupling scales of the order of $10^6$ GeV for both $b\to d$ and $b \to s$ transitions.

The gradient flow transformation can be interpreted as continuous real-space renormalization group transformation if a coarse-graining step is incorporated as part of calculating expectation values. The method allows to predict critical properties of strongly coupled systems including the renormalization group $\beta$ function and anomalous dimensions at nonperturbative fixed points. In this contribution we discuss a new analysis of the continuous renormalization group $\beta$ function for $N_f=2$ and $N_f=12$ fundamental flavors in SU(3) gauge theories based on this method. We follow the approach developed and tested for the $N_f=2$ system in arXiv:1910.06408. Here we present further information on the analysis, emphasizing the robustness and intuitive features of the continuous $\beta$ function calculation. We also discuss the applicability of the continuous $\beta$ function calculation in conformal systems, extending the possible phase diagram to include a 4-fermion interaction. The numerical analysis for $N_f=12$ uses the same set of ensembles that was generated and analyzed for the step scaling function in arXiv:1909.05842. The new analysis uses volumes with $L \ge 20$ and determines the $\beta$ function in the $c=0$ gradient flow renormalization scheme. The continuous $\beta$ function predicts the existence of a conformal fixed point and is consistent between different operators. Although determinations of the step scaling and continuous $\beta$ function use different renormalization schemes, they both predict the existence of a conformal fixed point around $g^2\sim 6$.

We present a novel approach to compute the force between a static quark and a static antiquark from lattice gauge theory directly, rather than extracting it from the static energy. We explore this approach for SU(3) pure gauge theory using the multilevel algorithm and smeared operators.

We present a Markov-Chain Monte-Carlo (MCMC) forecast for the precision of neutrino mass and cosmological parameter measurements with a Euclid-like galaxy clustering survey. We use a complete perturbation theory model for the galaxy one-loop power spectrum and tree-level bispectrum, which includes bias, redshift space distortions, IR resummation for baryon acoustic oscillations and UV counterterms. The latter encapsulate various effects of short-scale dynamics which cannot be modeled within perturbation theory. Our MCMC procedure consistently computes the non-linear power spectra and bispectra as we scan over different cosmologies. The second ingredient of our approach is the theoretical error covariance which captures uncertainties due to higher-order non-linear corrections omitted in our model. Having specified characteristics of a Euclid-like spectroscopic survey, we generate and fit mock galaxy power spectrum and bispectrum likelihoods. Our results suggest that even under very agnostic assumptions about non-linearities and short-scale physics a future Euclid-like survey will be able to measure the sum of neutrino masses with a standard deviation of 28 meV . When combined with the Planck cosmic microwave background likelihood, this uncertainty decreases to 13 meV . Over-optimistically reducing the theoretical error on the bispectrum down to the two-loop level marginally tightens this bound to 11 meV . Moreover, we show that the future large-scale structure (LSS) spectroscopic data will greatly improve constraints on the other cosmological parameters, e.g. reaching a percent (per mille) error on the Hubble constant with LSS alone (LSS + Planck).

Nuclear structure models built from phenomenological mean fields, the effective nucleon–nucleon interactions (or Lagrangians), and the realistic bare nucleon–nucleon interactions are reviewed. The success of covariant density functional theory (CDFT) to describe nuclear properties and its influence on Brueckner theory within the relativistic framework are focused upon. The challenges and ambiguities of predictions for unstable nuclei without data or for high-density nuclear matter, arising from relativistic density functionals, are discussed. The basic ideas in building an ab initio relativistic density functional for nuclear structure from ab initio calculations with realistic nucleon–nucleon interactions for both nuclear matter and finite nuclei are presented. The current status of fully self-consistent relativistic Brueckner–Hartree–Fock (RBHF) calculations for finite nuclei or neutron drops (ideal systems composed of a finite number of neutrons and confined within an external field) is reviewed. The guidance and perspectives towards an ab initio covariant density functional theory for nuclear structure derived from the RBHF results are provided.

We test exact marginality of the deformation describing the blow-up of a zero- size D(-1) brane bound to a background of D3-branes by analyzing the equations of motion of superstring field theory to third order in the size. In the process we review the derivation of the instanton profile from string theory, extending it to include α'-corrections.

The compact binary radio pulsar system J0453+1559 consists of a recycled pulsar as primary component of 1.559(5) M _⊙ and an unseen companion star of 1.174(4) M _⊙. Because of the relatively large orbital eccentricity of e = 0.1125, it was argued that the companion is a neutron star (NS), making it the NS with the lowest accurately determined mass to date. However, a direct observational determination of the nature of the companion is currently not feasible. Moreover, state-of-the-art stellar evolution and supernova modeling are contradictory concerning the possibility of producing such a low-mass NS remnant. Here we challenge the NS interpretation by reasoning that the lower-mass component could instead be a white dwarf born in a thermonuclear electron-capture supernova (tECSN) event, in which oxygen-neon deflagration in the degenerate stellar core of an ultra-stripped progenitor ejects several 0.1 M _⊙ of matter and leaves a bound ONeFe white dwarf as the second-formed compact remnant. We determine the ejecta mass and remnant kick needed in this scenario to explain the properties of PSR J0453+1559 by a NS-white dwarf system. More work on tECSNe is needed to assess the viability of this scenario.

Confining hidden sectors are an attractive possibility for physics beyond the Standard Model (SM). They are especially motivated by neutral naturalness theories, which reconcile the lightness of the Higgs with the strong constraints on colored top partners. We study hidden QCD with one light quark flavor, coupled to the SM via effective operators suppressed by the mass M of new electroweak-charged particles. This effective field theory is inspired by a new tripled top model of supersymmetric neutral naturalness. The hidden sector is accessed primarily via the Z and Higgs portals, which also mediate the decays of the hidden mesons back to SM particles. We find that exotic Z decays at the LHC and future Z factories provide the strongest sensitivity to this scenario, and we outline a wide array of searches. For a larger hidden confinement scale Λ ∼ O (10) GeV, the exotic Z decays dominantly produce final states with two hidden mesons. ATLAS and CMS can probe their prompt decays up to M ∼ 3 TeV at the high luminosity phase, while a TeraZ factory would extend the reach up to M ∼ 20 TeV through a combination of searches for prompt and displaced signals. For smaller Λ ∼ O (1) GeV, the Z decays to the hidden sector produce jets of hidden mesons, which are long-lived. LHCb will be a powerful probe of these emerging jets. Furthermore, the light hidden vector meson could be detected by proposed dark photon searches.

We present high angular resolution (∼80 mas) ALMA continuum images of the SN 1987A system, together with CO J = 2 \to 1, J = 6 \to 5, and SiO J = 5 \to 4 to J = 7 \to 6 images, which clearly resolve the ejecta (dust continuum and molecules) and ring (synchrotron continuum) components. Dust in the ejecta is asymmetric and clumpy, and overall the dust fills the spatial void seen in Hα images, filling that region with material from heavier elements. The dust clumps generally fill the space where CO J = 6 \to 5 is fainter, tentatively indicating that these dust clumps and CO are locationally and chemically linked. In these regions, carbonaceous dust grains might have formed after dissociation of CO. The dust grains would have cooled by radiation, and subsequent collisions of grains with gas would also cool the gas, suppressing the CO J = 6 \to 5 intensity. The data show a dust peak spatially coincident with the molecular hole seen in previous ALMA CO J = 2 \to 1 and SiO J = 5 \to 4 images. That dust peak, combined with CO and SiO line spectra, suggests that the dust and gas could be at higher temperatures than the surrounding material, though higher density cannot be totally excluded. One of the possibilities is that a compact source provides additional heat at that location. Fits to the far-infrared-millimeter spectral energy distribution give ejecta dust temperatures of 18-23 K. We revise the ejecta dust mass to M _dust = 0.2-0.4 {M}_⊙ for carbon or silicate grains, or a maximum of <0.7 {M}_⊙ for a mixture of grain species, using the predicted nucleosynthesis yields as an upper limit.

We argue that the tree-level graviton-scalar scattering in the Regge limit is unitarized by non-perturbative effects within General Relativity alone, that is without resorting to any extension thereof. At Planckian energy the back reaction of the incoming graviton on the background geometry produces a non-perturbative plane wave which softens the UV-behavior in turn. Our amplitude interpolates between the perturbative graviton-scalar scattering at low energy and scattering on a classical plane wave in the Regge limit that is bounded for all values of s.

The goal of blinding is to hide an experiment’s critical results – here the inferred cosmological parameters – until all decisions affecting its analysis have been finalized. This is especially important in the current era of precision cosmology, when the results of any new experiment are closely scrutinized for consistency or tension with previous results. In analyses that combine multiple observational probes, like the combination of galaxy clustering and weak lensing in the Dark Energy Survey (DES), it is challenging to blind the results while retaining the ability to check for (in)consistency between different parts of the data. We propose a simple new blinding transformation, which works by modifying the summary statistics that are input to parameter estimation, such as two-point correlation functions. The transformation shifts the measured statistics to new values that are consistent with (blindly) shifted cosmological parameters while preserving internal (in)consistency. We apply the blinding transformation to simulated data for the projected DES Year 3 galaxy clustering and weak lensing analysis, demonstrating that practical blinding is achieved without significant perturbation of internal-consistency checks, as measured here by degradation of the χ^2 between the data and best-fitting model. Our blinding method’s performance is expected to improve as experiments evolve to higher precision and accuracy.

Cosmic voids gravitationally lens the cosmic microwave background (CMB) radiation, resulting in a distinct imprint on degree scales. We use the simulated CMB lensing convergence map from the Marenostrum Institut de Ciencias de l’Espai (MICE) N-body simulation to calibrate our detection strategy for a given void definition and galaxy tracer density. We then identify cosmic voids in Dark Energy Survey (DES) Year 1 data and stack the Planck 2015 lensing convergence map on their locations, probing the consistency of simulated and observed void lensing signals. When fixing the shape of the stacked convergence profile to that calibrated from simulations, we find imprints at the 3σ significance level for various analysis choices. The best measurement strategies based on the MICE calibration process yield S/N ≈ 4 for DES Y1, and the best-fitting amplitude recovered from the data is consistent with expectations from MICE (A ≈ 1). Given these results as well as the agreement between them and N-body simulations, we conclude that the previously reported excess integrated Sachs–Wolfe (ISW) signal associated with cosmic voids in DES Y1 has no counterpart in the Planck CMB lensing map.

We present a blind time-delay cosmographic analysis for the lens system DES J0408−5354. This system is extraordinary for the presence of two sets of multiple images at different redshifts, which provide the opportunity to obtain more information at the cost of increased modelling complexity with respect to previously analysed systems. We perform detailed modelling of the mass distribution for this lens system using three band Hubble Space Telescope imaging. We combine the measured time delays, line-of-sight central velocity dispersion of the deflector, and statistically constrained external convergence with our lens models to estimate two cosmological distances. We measure the ‘effective’ time-delay distance corresponding to the redshifts of the deflector and the lensed quasar |$D_{\Delta t}^{\rm eff}=$||$3382_{-115}^{+146}$| Mpc and the angular diameter distance to the deflector D_d = |$1711_{-280}^{+376}$| Mpc, with covariance between the two distances. From these constraints on the cosmological distances, we infer the Hubble constant H_0= |$74.2_{-3.0}^{+2.7}$| km s^−1 Mpc^−^1 assuming a flat ΛCDM cosmology and a uniform prior for Ω_m as |$\Omega _{\rm m} \sim \mathcal {U}(0.05, 0.5)$|⁠. This measurement gives the most precise constraint on H_0 to date from a single lens. Our measurement is consistent with that obtained from the previous sample of six lenses analysed by the H_0 Lenses in COSMOGRAIL’s Wellspring (H0LiCOW) collaboration. It is also consistent with measurements of H_0 based on the local distance ladder, reinforcing the tension with the inference from early Universe probes, for example, with 2.2σ discrepancy from the cosmic microwave background measurement.

The doubled target space of the fundamental closed string is identified with its phase space and described by an almost para-Hermitian geometry. We explore this setup in the context of group manifolds which admit a maximally isotropic subgroup. This leads to a formulation of the Poisson-Lie σ-model and Poisson-Lie T-duality in terms of para-Hermitian geometry. The emphasis is put on so called half-integrable setups where only one of the Lagrangian subspaces of the doubled space has to be integrable. Using the dressing coset construction in Poisson-Lie T-duality, we extend our construction to more general coset spaces. This allows to explicitly obtain a huge class of para-Hermitian geometries. Each of them is automatically equipped which a generalized frame field, required for consistent generalized Scherk-Schwarz reductions. As examples we present integrable λ- and η-deformations on the three- and two-sphere.

The effect of galactic orbits on a galaxy's internal evolution within a galaxy cluster environment has been the focus of heated debate in recent years. To understand this connection, we use both the (0.5 Gpc)³ and the Gpc³ boxes from the cosmological hydrodynamical simulation set Magneticum Pathfinder. We investigate the velocity anisotropy, phase space, and the orbital evolution of up to ∼5 × 10⁵ resolved satellite galaxies within our sample of 6776 clusters with M_{vir} > 10^{14} M_{⊙ } at low redshift, which we also trace back in time. In agreement with observations, we find that star-forming satellite galaxies inside galaxy clusters are characterized by more radially dominated orbits, independent of cluster mass. Furthermore, the vast majority of star-forming satellite galaxies stop forming stars during their first passage. We find a strong dichotomy both in line-of-sight and radial phase space between star-forming and quiescent galaxies, in line with observations. The tracking of individual orbits shows that the star formation of almost all satellite galaxies drops to zero within 1 Gyr after infall. Satellite galaxies that are able to remain star forming longer are characterized by tangential orbits and high stellar mass. All this indicates that in galaxy clusters the dominant quenching mechanism is ram-pressure stripping.

We propose a mechanism to solve the Higgs naturalness problem through a cosmological selection process. The discharging of excited field configurations through membrane nucleation leads to discrete jumps of the cosmological constant and the Higgs mass, which vary in a correlated way. The resulting multitude of universes are all empty, except for those in which the cosmological constant and the Higgs mass are both nearly vanishing. Only under these critical conditions can inflation be activated and create a non-empty universe.

A tight relation between the [C II] 158 μm line luminosity and star formation rate is measured in local galaxies. At high redshift (z > 5), though, a much larger scatter is observed, with a considerable (15-20 per cent) fraction of the outliers being [C II]-deficient. Moreover, the [C II] surface brightness (Σ_[C II]) of these sources is systematically lower than expected from the local relation. To clarify the origin of such [C II]-deficiency, we have developed an analytical model that fits local [C II] data and has been validated against radiative transfer simulations performed with CLOUDY. The model predicts an overall increase of Σ_[C II] with Σ_SFR. However, for Σ_SFR {≳} 1 M_⊙ yr^{-1} kpc^{-2}, Σ_[C II] saturates. We conclude that underluminous [C II] systems can result from a combination of three factors: (a) large upward deviations from the Kennicutt-Schmidt relation (κ_s ≫ 1), parametrized by the `burstiness' parameter κ_s; (b) low metallicity; (c) low gas density, at least for the most extreme sources (e.g. CR7). Observations of [C II] emission alone cannot break the degeneracy among the above three parameters; this requires additional information coming from other emission lines (e.g. [O III]88 μm, C III]1909 Å, CO lines). Simple formulae are given to interpret available data for low- and high-z galaxies.

Two-fluid (electron-positron) plasma modeling has shown that inductive acceleration can convert Poynting flux directly into bulk kinetic energy in the relativistic flows driven by rotating magnetized neutron stars and black holes. Here, we generalize this approach by adding an ion fluid. Solutions are presented in which all particles are accelerated as the flow expands, with comparable power channeled into each of the plasma components. In an ion-dominated flow, each species reaches the limiting rigidity, according to Hillas’ criterion, in a distance significantly shorter than in a lepton-dominated flow. These solutions support the hypothesis that newly born magnetars and pulsars are potential sources of ultrahigh energy cosmic rays. The competing process of Poynting flux dissipation by magnetic reconnection is shown to be ineffective in low-density flows in which the conventionally defined electron multiplicity satisfies {κ }_{{e}}≲ {10}⁵{≤ft(4π {L}₃₈/{{Ω }}\right)}^1/4/{{Max}}≤ft({η }_ion}^1/2,1\right), where L ₃₈ × 10³⁸ erg s^-1 is the power carried by the flow in a solid angle Ω, and {η }_ion} is the ratio of the ion to lepton power at launch.

Recent high-resolution interferometric observations of protoplanetary disks at (sub)millimeter wavelengths reveal omnipresent substructures, such as rings, spirals, and asymmetries. A detailed investigation of eight rings detected in five disks by the DSHARP survey came to the conclusion that all rings are just marginally optically thick with optical depths between 0.2 and 0.5 at a wavelength of 1.25 mm. This surprising result could either be coincidental or indicate that the optical depth in all of the rings is regulated by the same process. We investigated if ongoing planetesimal formation could explain the “fine-tuned” optical depths in the DSHARP rings by removing dust and transforming it into “invisible” planetesimals. We performed a one-dimensional simulation of dust evolution in the second dust ring of the protoplanetary disk around HD 163296, including radial transport of gas and dust, dust growth and fragmentation, and planetesimal formation via gravitational collapse of sufficiently dense pebble concentrations. We show that planetesimal formation can naturally explain the observed optical depths if streaming instability regulates the midplane dust-to-gas ratio to unity. Furthermore, our simple monodisperse analytical model supports the hypothesis that planetesimal formation in dust rings should universally limit their optical depth to the observed range.

We present Period-Luminosity and Period-Luminosity-Color relations at maximum light for Mira variables in the Magellanic Clouds using time-series data from the Optical Gravitational Lensing Experiment (OGLE-III) and Gaia data release 2. The maximum-light relations exhibit a scatter typically up to ∼30% smaller than their mean-light counterparts. The apparent magnitudes of oxygen-rich Miras at maximum light display significantly smaller cycle-to-cycle variations than at minimum light. High-precision photometric data for Kepler Mira candidates also exhibit stable magnitude variations at the brightest epochs, while their multi-epoch spectra display strong Balmer emission lines and weak molecular absorption at maximum light. The stability of maximum-light magnitudes for Miras possibly occurs due to the decrease in the sensitivity to molecular bands at their warmest phase. At near-infrared wavelengths, the period-luminosity relations (PLRs) of Miras display similar dispersion at mean and maximum light with limited time-series data in the Magellanic Clouds. A kink in the oxygen-rich Mira PLRs is found at 300 days in the VI-bands, which shifts to longer periods (∼350 days) at near-infrared wavelengths. Oxygen-rich Mira PLRs at maximum light provide a relative distance modulus, Δμ = 0.48 ± 0.08 mag, between the Magellanic Clouds with a smaller statistical uncertainty than the mean-light relations. The maximum-light properties of Miras can be very useful for stellar atmosphere modeling and distance scale studies provided their stability and the universality can be established in other stellar environments in the era of extremely large telescopes.

Neutron star mergers can form a hypermassive neutron star (HMNS) remnant, which may be the engine of a short gamma-ray burst (SGRB) before it collapses to a black hole, possibly several hundred milliseconds after the merger. During the lifetime of an HMNS, numerical relativity simulations indicate that it will undergo strong oscillations and emit gravitational waves with frequencies of a few kilohertz, which are unfortunately too high for detection to be probable with the Advanced Laser Interferometer Gravitational-Wave Observatory. Here we discuss the current and future prospects for detecting these frequencies as modulation of the SGRB. The understanding of the physical mechanism responsible for the HMNS oscillations will provide information on the equation of state of the hot HMNS, and the observation of these frequencies in the SGRB data would give us insight into the emission mechanism of the SGRB.

We present results from a comparative study of light curves of Cepheid and RR Lyrae stars in the Galaxy and the Magellanic Clouds with their theoretical models generated from the stellar pulsation codes. Fourier decomposition method is used to analyse the theoretical and the observed light curves at multiple wavelengths. In case of RR Lyrae stars, the amplitude and Fourier parameters from the models are consistent with observations in most period bins except for low metal-abundances (Z < 0:004). In case of Cepheid variables, we observe a greater offset between models and observations for both the amplitude and Fourier parameters. The theoretical amplitude parameters are typically larger than those from observations, except close to the period of 10 days. We find that these discrepancies between models and observations can be reduced if a higher convective efficiency is adopted in the pulsation codes. Our results suggest that a quantitative comparison of light curve structure is very useful to provide constraints for the input physics to the stellar pulsation models.

Dust temperature is an important property of the interstellar medium (ISM) of galaxies. It is required when converting (sub)millimetre broad-band flux to total infrared luminosity (L_IR), and hence star formation rate, in high-redshift galaxies. However, different definitions of dust temperatures have been used in the literature, leading to different physical interpretations of how ISM conditions change with, e.g. redshift and star formation rate. In this paper, we analyse the dust temperatures of massive (M_star > 10^{10} M_{\odot }) z = 2-6 galaxies with the help of high-resolution cosmological simulations from the Feedback in Realistic Environments (FIRE) project. At z ∼ 2, our simulations successfully predict dust temperatures in good agreement with observations. We find that dust temperatures based on the peak emission wavelength increase with redshift, in line with the higher star formation activity at higher redshift, and are strongly correlated with the specific star formation rate. In contrast, the mass-weighted dust temperature, which is required to accurately estimate the total dust mass, does not strongly evolve with redshift over z = 2-6 at fixed IR luminosity but is tightly correlated with L_IR at fixed z. We also analyse an `equivalent' dust temperature for converting (sub)millimetre flux density to total IR luminosity, and provide a fitting formula as a function of redshift and dust-to-metal ratio. We find that galaxies of higher equivalent (or higher peak) dust temperature (`warmer dust') do not necessarily have higher mass-weighted temperatures. A `two-phase' picture for interstellar dust can explain the different scaling relations of the various dust temperatures.

We study for the first time the collider reach on the derivative Higgs portal, the leading effective interaction that couples a pseudo Nambu-Goldstone boson (pNGB) scalar Dark Matter to the Standard Model. We focus on Dark Matter pair production through an off-shell Higgs boson, which is analyzed in the vector boson fusion channel. A variety of future high-energy lepton colliders as well as hadron colliders are considered, including CLIC, a muon collider, the High-Luminosity and High-Energy versions of the LHC, and FCC-hh. Implications on the parameter space of pNGB Dark Matter are discussed. In addition, we give improved and extended results for the collider reach on the marginal Higgs portal, under the assumption that the new scalars escape the detector, as motivated by a variety of beyond the Standard Model scenarios.

Atmospheric neutrinos produced by cosmic-ray interactions around the globe provide a beam for the study of neutrino properties. They are also a background in searches for neutrinos of astrophysical origin. Both aspects are addressed in this chapter, which begins with a brief introduction on neutrino oscillations in relation to the spectrum of atmospheric neutrinos. Section 2 describes the cascade equation for hadrons in the atmosphere and the main features of atmospheric leptons from their decays. Next, uncertainties in the fluxes that arise from limited knowledge of the primary spectrum and of particle production are discussed. The final section covers aspects specific to neutrino telescopes.

Turbulence is the natural state of many weakly collisional space and astrophysical plasmas.

Prominent examples range from the near-Earth solar wind, to more distant astrophysical systems such as the warm interstellar medium, hot accretion flows, and galaxy clusters. In low-collisionality turbulent plasmas, it is anticipated theoretically and documented observationally that the electromagnetic energy cascade extends beyond the inertial, magnetohydrodynamic range into the plasma kinetic range of scales. Upon transition into the kinetic range, below the ion gyroradius and the ion inertial scale, the character of the turbulence changes significantly compared to the magnetohydrodynamic turbulence. The nature of this kinetic-scale turbulence is presently the subject of ongoing investigations, with important implications for the general thermodynamic properties of weakly collisional plasmas.

This document summarises the current theoretical and experimental status of the di-Higgs boson production searches, and of the direct and indirect constraints on the Higgs boson self-coupling, with the wish to serve as a useful guide for the next years. The document discusses the theoretical status, including state-of-the-art predictions for di-Higgs cross sections, developments on the effective field theory approach, and studies on specific new physics scenarios that can show up in the di-Higgs final state. The status of di-Higgs searches and the direct and indirect constraints on the Higgs self-coupling at the LHC are presented, with an overview of the relevant experimental techniques, and covering all the variety of relevant signatures. Finally, the capabilities of future colliders in determining the Higgs self-coupling are addressed, comparing the projected precision that can be obtained in such facilities. The work has started as the proceedings of the Di-Higgs workshop at Colliders, held at Fermilab from the 4th to the 9th of September 2018, but it went beyond the topics discussed at that workshop and included further developments. FERMILAB-CONF-19-468-E-T, LHCHXSWG-2019-005

Fast radio bursts (FRBs) are an enigmatic class of extragalactic transients emitting Jy-level radio bursts in the GHz band, lasting for only a few ms. So far, some objects are known to repeat while several others are not, likely indicating multiple origins. There are many theoretical models, some predict prompt VHE or optical emission correlated with FRBs while others imply VHE afterglows hours after the FRB. To test these predictions and unravel the nature of FRB progenitors, the stereoscopic Imaging Atmospheric Cherenkov Telescopes (IACTs) system MAGIC has been participating in FRB observation campaigns since 2016. As IACTs are sensitive to Cherenkov photons in the UV/blue region of the electromagnetic spectrum and use photo-detectors with time response faster than a ms, MAGIC is also able to perform simultaneous optical observations through a dedicated system installed in the central PMT of its camera. The main challenge faced by MAGIC in searching for optical counterpart of FRBs is the presence of irreducible background optical events due to terrestrial sources. We present new results from MAGIC observations of the first repeating FRB 121102 during several MWL observation campaigns. The recently improved instrument and refined strategy to search for counterparts of FRBs in the VHE and optical bands will also be presented

What are the mass and galaxy profiles of cosmic voids? In this paper, we use two methods to extract voids in the Dark Energy Survey (DES) Year 1 redMaGiC galaxy sample to address this question. We use either 2D slices in projection, or the 3D distribution of galaxies based on photometric redshifts to identify voids. For the mass profile, we measure the tangential shear profiles of background galaxies to infer the excess surface mass density. The signal-to-noise ratio for our lensing measurement ranges between 10.7 and 14.0 for the two void samples. We infer their 3D density profiles by fitting models based on N-body simulations and find good agreement for void radii in the range 15–85 Mpc. Comparison with their galaxy profiles then allows us to test the relation between mass and light at the 10 per cent level, the most stringent test to date. We find very similar shapes for the two profiles, consistent with a linear relationship between mass and light both within and outside the void radius. We validate our analysis with the help of simulated mock catalogues and estimate the impact of photometric redshift uncertainties on the measurement. Our methodology can be used for cosmological applications, including tests of gravity with voids. This is especially promising when the lensing profiles are combined with spectroscopic measurements of void dynamics via redshift-space distortions.

We describe the minimal space of polylogarithmic functions that is required to express the six-particle amplitude in planar N = 4 super-Yang-Mills theory through six and seven loops, in the NMHV and MHV sectors respectively. This space respects a set of extended Steinmann relations that restrict the iterated discontinuity structure of the amplitude, as well as a cosmic Galois coaction principle that constrains the functions and the transcendental numbers that can appear in the amplitude at special kinematic points. To put the amplitude into this space, we must divide it by the BDS-like ansatz and by an additional zeta-valued constant ρ. For this normalization, we conjecture that the extended Steinmann relations and the coaction principle hold to all orders in the coupling. We describe an iterative algorithm for constructing the space of hexagon functions that respects both constraints. We highlight further simplifications that begin to occur in this space of functions at weight eight, and distill the implications of imposing the coaction principle to all orders. Finally, we explore the restricted spaces of transcendental functions and constants that appear in special kinematic configurations, which include polylogarithms involving square, cube, fourth and sixth roots of unity.

Using the latest LHC data, we analyse and compare the lower limits on the masses of gluinos and the lightest stop in two natural supersymmetric motivated scenarios: one with a neutralino being the lightest supersymmetric particle (LSP) and the other one with gravitino as the LSP and neutralino as the next-to-lightest supersymmetric particle. In the second case our analysis applies to neutralinos promptly decaying to very light gravitinos, which are of cosmological interest, and are generic for low, of order O (100) TeV, messenger scale in gauge mediation models. We find that the lower bounds on the gluino and the lightest stop masses are stronger for the gravitino LSP scenarios due to the extra handle from the decay products of neutralinos. Generally, in contrast to the neutralino LSP case the limits now extend to a region of compressed spectrum. In bino scenarios the highest excluded stop mass increases from 1000 GeV to almost 1400 GeV. Additionally, in the higgsino-like NLSP scenario the higgsinos below 650 GeV are universally excluded and the stop mass limit is {m}_{\tilde{t}} > 1150 GeV, whereas there is no limit on stops in the higgsino LSP model for {m}_{\tilde{h}} = 650 GeV. Nevertheless, we find that the low messenger scale still ameliorates the fine tuning in the electroweak potential.

Inverse Compton-pair cascades are initiated when gamma-rays are absorbed on an ambient soft photon field to produce relativistic pairs, which in turn up-scatter the same soft photons to produce more gamma-rays. If the Compton scatterings take place in the deep Klein-Nishina regime, then triplet pair production (e{γ }_b\to {{ee}}⁺{e}^-) becomes relevant and may even regulate the development of the cascade. We investigate the properties of pair-Compton cascades with triplet pair production in accelerating gaps, i.e., regions with an unscreened electric field. Using the method of transport equations for the particle evolution, we compute the growth rate of the pair cascade as a function of the accelerating electric field in the presence of blackbody and power-law ambient photon fields. Informed by the numerical results, we derive simple analytical expressions for the peak growth rate and the corresponding electric field. We show that for certain parameters, which can be realized in the vicinity of accreting supermassive black holes at the centers of active galactic nuclei, the pair cascade may well be regulated by inverse Compton scattering in the deep Klein-Nishina regime and triplet pair production. We present indicative examples of the escaping gamma-ray radiation from the gap, and discuss our results in application to the TeV observations of radio galaxy M87.

Rare B-decays induced by flavour-changing neutral currents (FCNC) is one of the promising candidates for probing physics beyond the Standard model. However, for identifying potential new physics from the data, reliable control over QCD contributions is necessary. We focus on one of such QCD contributions - the charming loops - that potentially can lead to difficulties in disentangling new physics effects from the observable and discuss the possibility to gain control over theoretical predictions for charming loops.

Dark matter evolution during the process of cosmological structure formation can be described in terms of a one-particle irreducible effective action at a characteristic scale k_m and a loop expansion below this scale, based on the effective propagators and vertices. We calculate the form of the effective vertices and compute the bispectrum of density perturbations within a one-loop approximation. We find that the effective vertices play a subdominant role as compared to the effective viscosity and sound velocity that modify the (inverse) propagators. For the bispectrum we reproduce the results of standard perturbation theory in the range where it is applicable, and find a slightly improved agreement with N-body simulations at larger wavenumbers.

In the simple Higgs-portal dark matter model with a conserved dark matter number, we show that there exists a non-topological soliton state of dark matter. This state has smaller energy per dark matter number than a free particle state and has its interior in the electroweak symmetric vacuum. It could be produced in the early universe from first-order electroweak phase transition and contribute most of dark matter. This electroweak symmetric dark matter ball is a novel macroscopic dark matter candidate with an energy density of the electroweak scale and a mass of 1 gram or above. Because of its electroweak-symmetric interior, the dark matter ball has a large geometric scattering cross section off a nucleon or a nucleus. Dark matter and neutrino experiments with a large-size detector like Xenon1T, BOREXINO and JUNO have great potential to discover electroweak symmetric dark matter balls. We also discuss the formation of bound states of a dark matter ball and ordinary matter.

We study the soft limit of a recently proposed generalization of the biadjoint scalar amplitudes $m^{(k)}_{n}$, which have been conjectured to have a relation to the tropical Grassmannian $\text{Tr G}(k,n)$. Using the CHY formulation along with the Global Residue Theorem, we prove the soft factorization for $m^{(k)}_{n}$ amplitudes for arbitrary $k$ and $n$. We find that the soft factors are in direct correspondence to vertices of the associahedron $\mathcal{A}_{k-1}$, and hence take the form of $m^{(2)}_{n}$ amplitudes. This entails that all scattering amplitudes of the ordinary biadjoint scalar theory can be interpreted as an infinite family of soft factors. Additionally, Grassmannian duality reveals that generalized amplitudes $m^{(k)}_{n}$ with $k>2$ satisfy not only a soft theorem, but also a non-trivial "hard" theorem. We perform numerical checks of our theorems against previous results for $\text{Tr G}(4,7)$ and $\text{Tr G}(5,8)$, thereby providing strong evidence of their relation with the CHY formulation.

The in-medium dynamics of heavy particles are governed by transport coefficients. The heavy quark momentum diffusion coefficient, κ , is an object of special interest in the literature, but one which has proven notoriously difficult to estimate, despite the fact that it has been computed by weak-coupling methods at next-to-leading order accuracy, and by lattice simulations of the pure SU(3) gauge theory. Another coefficient, γ , has been recently identified. It can be understood as the dispersive counterpart of κ . Little is known about γ . Both κ and γ are, however, of foremost importance in heavy quarkonium physics as they entirely determine the in and out of equilibrium dynamics of quarkonium in a medium, if the evolution of the density matrix is Markovian, and the motion, quantum Brownian; the medium could be a strongly or weakly coupled plasma. In this paper, using the relation between κ , γ and the quarkonium in-medium width and mass shift respectively, we evaluate the two coefficients from existing 2 +1 flavor lattice QCD data. The resulting range for κ is consistent with earlier determinations, the one for γ is the first nonperturbative determination of this quantity.

We present a method to flexibly and self-consistently determine individual galaxies' star formation rates (SFRs) from their host haloes' potential well depths, assembly histories, and redshifts. The method is constrained by galaxies' observed stellar mass functions, SFRs (specific and cosmic), quenched fractions, ultraviolet (UV) luminosity functions, UV-stellar mass relations, IRX-UV relations, auto- and cross-correlation functions (including quenched and star-forming subsamples), and quenching dependence on environment; each observable is reproduced over the full redshift range available, up to 0 < z < 10. Key findings include the following: galaxy assembly correlates strongly with halo assembly; quenching correlates strongly with halo mass; quenched fractions at fixed halo mass decrease with increasing redshift; massive quenched galaxies reside in higher-mass haloes than star-forming galaxies at fixed galaxy mass; star-forming and quenched galaxies' star formation histories at fixed mass differ most at z < 0.5; satellites have large scatter in quenching time-scales after infall, and have modestly higher quenched fractions than central galaxies; Planck cosmologies result in up to 0.3 dex lower stellar - halo mass ratios at early times; and, none the less, stellar mass-halo mass ratios rise at z > 5. Also presented are revised stellar mass - halo mass relations for all, quenched, star-forming, central, and satellite galaxies; the dependence of star formation histories on halo mass, stellar mass, and galaxy SSFR; quenched fractions and quenching time-scale distributions for satellites; and predictions for higher-redshift galaxy correlation functions and weak lensing surface densities. The public data release (DR1) includes the massively parallel (>10⁵ cores) implementation (the UNIVERSEMACHINE), the newly compiled and remeasured observational data, derived galaxy formation constraints, and mock catalogues including lightcones.

We present a simple and well defined prescription to compare absorption lines in supernova (SN) spectra with lists of transitions drawn from the National Institute of Standards and Technology database. The method is designed to be applicable to simple spectra where the photosphere can be mostly described by absorptions from single transitions with a single photospheric velocity. These conditions are plausible for SN spectra obtained shortly after explosion. Here we show that the method also works well for spectra of hydrogen-poor (Type I) superluminous supernovae (SLSNe-I) around peak. Analysis of high signal to noise spectra leads to clear identification of numerous spectroscopic features arising from ions of carbon and oxygen, which account for the majority of absorption features detected in the optical range, suggesting the outer envelope of SLSN-I progenitors is dominated by these elements. We find that the prominent absorption features seen in the blue are dominated by numerous lines of O II, as previously suggested, and that the apparent absorption feature widths are dominated by line density and not by Doppler broadening. In fact, we find that while the expansion velocities of SLSNe-I around peak are similar to those of normal SNe, the apparent velocity distribution (manifested as the width of single transition features) is much lower (∼1500 km s^-1) indicating emission from a very narrow photosphere in velocity space that is nevertheless expanding rapidly. We inspect the controversial case of ASASSN-15lh, and find that the early spectrum of this object is not consistent with those of SLSNe-I. We also show that SLSNe that initially lack hydrogen features but develop these at late phases, such as iPTF15esb and iPTF16bad, also differ in their early spectra from standard SLSNe-I.

This is the first installment of a series of three papers in which we describe a method to determine higher-point correlation functions in one-loop open-superstring amplitudes from first principles. In this first part, we exploit the synergy between the co-homological features of pure-spinor superspace and the pure-spinor zero-mode integration rules of the one-loop amplitude prescription. This leads to the study of a rich variety of multiparticle superfields which are local, have covariant BRST variations, and are compatible with the particularities of the pure-spinor amplitude prescription. Several objects related to these superfields, such as their non-local counterparts and the so-called BRST pseudo-invariants, are thoroughly reviewed and put into new light. Their properties will turn out to be mysteriously connected to products of one-loop worldsheet functions in packages dubbed "generalized elliptic integrands", whose prominence will be seen in the later parts of this series of papers.

This is the second installment of a series of three papers in which we describe a method to determine higher-point correlation functions in one-loop open-superstring amplitudes from first principles. In this second part, we study worldsheet functions defined on a genus-one surface built from the coefficient functions of the Kronecker-Einsenstein series. We construct two classes of worldsheet functions whose properties lead to several simplifying features within our description of one-loop correlators with the pure-spinor formalism. The first class is described by functions with prescribed monodromies, whose characteristic shuffle-symmetry property leads to a Lie-polynomial structure when multiplied by the local superfields from part I of this series. The second class is given by so-called generalized elliptic integrands (GEIs) that are constructed using the same combinatorial patterns of the BRST pseudo-invariant superfields from part I. Both of them lead to compact and combinatorially rich expressions for the correlators in part III. The identities obeyed by the two classes of worldsheet functions exhibit striking parallels with those of the superfield kinematics. We will refer to this phenomenon as a duality between worldsheet functions and kinematics.

In this final part of a series of three papers, we will assemble supersymmetric expressions for one-loop correlators in pure-spinor superspace that are BRST invariant, local, and single valued. A key driving force in this construction is the generalization of a so far unnoticed property at tree-level; the correlators have the symmetry structure akin to Lie polynomials. One-loop correlators up to seven points are presented in a variety of representations manifesting different subsets of their defining properties. These expressions are related via identities obeyed by the kinematic superfields and worldsheet functions spelled out in the first two parts of this series and reflecting a duality between the two kinds of ingredients. Interestingly, the expression for the eight-point correlator following from our method seems to capture correctly all the dependence on the worldsheet punctures but leaves undetermined the coefficient of the holomorphic Eisenstein series G₄. By virtue of chiral splitting, closed-string correlators follow from the double copy of the open-string results.

We study the formation and evolution of a sample of Lyman break galaxies in the epoch of reionization by using high-resolution (∼10 pc), cosmological zoom-in simulations part of the SERRA suite. In SERRA, we follow the interstellar medium thermochemical non-equilibrium evolution and perform on-the-fly radiative transfer of the interstellar radiation field (ISRF). The simulation outputs are post-processed to compute the emission of far infrared lines ([C II], [N II], and [O III]). At z = 8, the most massive galaxy, `Freesia', has an age t_\star ∼eq 409 Myr, stellar mass M_⋆ ≃ 4.2 × 10⁹M_⊙, and a star formation rate (SFR), SFR∼eq 11.5 M_{⊙ } yr^{-1}, due to a recent burst. Freesia has two stellar components (A and B) separated by ≃ 2.5 kpc; other 11 galaxies are found within 56.9 ± 21.6 kpc. The mean ISRF in the Habing band is G = 7.9 G_0 and is spatially uniform; in contrast, the ionization parameter is U = 2^{+20}_{-2} × 10^{-3}, and has a patchy distribution peaked at the location of star-forming sites. The resulting ionizing escape fraction from Freesia is f_esc∼eq 2{{ per cent}}. While [C II] emission is extended (radius 1.54 kpc), [O III] is concentrated in Freesia-A (0.85 kpc), where the ratio Σ _[O III]/Σ _[C II]≃ 10. As many high-z galaxies, Freesia lies below the local [C II]-SFR relation. We show that this is the general consequence of a starburst phase (pushing the galaxy above the Kennicutt-Schmidt relation) that disrupts/photodissociates the emitting molecular clouds around star-forming sites. Metallicity has a sub-dominant impact on the amplitude of [C II]-SFR deviations.

We study the kinematical properties of galaxies in the Epoch of Reionization via the [C II]158 μm line emission. The line profile provides information on the kinematics as well as structural properties such as the presence of a disc and satellites. To understand how these properties are encoded in the line profile, first we develop analytical models from which we identify disc inclination and gas turbulent motions as the key parameters affecting the line profile. To gain further insights, we use `Althæa', a highly resolved (30 pc) simulated prototypical Lyman-break galaxy, in the redshift range z = 6-7, when the galaxy is in a very active assembling phase. Based on morphology, we select three main dynamical stages: (I) merger, (II) spiral disc, and (III) disturbed disc. We identify spectral signatures of merger events, spiral arms, and extra-planar flows in (I), (II), and (III), respectively. We derive a generalized dynamical mass versus [C II]-line FWHM relation. If precise information on the galaxy inclination is (not) available, the returned mass estimate is accurate within a factor 2 (4). A Tully-Fisher relation is found for the observed high-z galaxies, i.e. L_{[C II]} ∝ (FWHM)^{1.80 ± 0.35} for which we provide a simple, physically based interpretation. Finally, we perform mock ALMA simulations to check the detectability of [C II]. When seen face-on, Althæa is always detected at >5σ; in the edge-on case it remains undetected because the larger intrinsic FWHM pushes the line peak flux below detection limit. This suggests that some of the reported non-detections might be due to inclination effects.

We compute the six-particle maximally-helicity-violating (MHV) and next-to-MHV (NMHV) amplitudes in planar maximally supersymmetric Yang-Mills theory through seven loops and six loops, respectively, as an application of the extended Steinmann relations and using the cosmic Galois coaction principle. Starting from a minimal space of functions constructed using these principles, we identify the amplitude by matching its symmetries and predicted behavior in various kinematic limits. Through five loops, the MHV and NMHV amplitudes are uniquely determined using only the multi-Regge and leading collinear limits. Beyond five loops, the MHV amplitude requires additional data from the kinematic expansion around the collinear limit, which we obtain from the Pentagon Operator Product Expansion, and in particular from its single-gluon bound state contribution. We study the MHV amplitude in the self-crossing limit, where its singular terms agree with previous predictions. Analyzing and plotting the amplitudes along various kinematical lines, we continue to find remarkable stability between loop orders.

We report on the catastrophic disintegration of P/2016 G1 (PANSTARRS), an active asteroid, in April 2016. Deep images over three months show that the object is made up of a central concentration of fragments surrounded by an elongated coma, and presents previously unreported sharp arc-like and narrow linear features. The morphology and evolution of these characteristics independently point toward a brief event on 2016 March 6. The arc and the linear feature can be reproduced by large particles on a ring, moving at 2.5 m s^-1. The expansion of the ring defines a cone with a 40° half-opening. We propose that the P/2016 G1 was hit by a small object which caused its (partial or total) disruption, and that the ring corresponds to large fragments ejected during the final stages of the crater formation.

We report the spectroscopic confirmation and modeling of the quadruply imaged quasar GRAL 113100-441959, the first gravitational lens (GL) to be discovered from a machine learning technique that only relies on the relative positions and fluxes of the observed images without considering colour informations. Follow-up spectra obtained with Keck/LRIS reveal the lensing nature of this quadruply imaged quasar with redshift z_s = 1.090 ± 0.002, but show no evidence of the central lens galaxy. Using the image positions and G-band flux ratios provided by Gaia Data Release 2 as constraints, we modeled the system with a singular power-law elliptical mass distribution (SPEMD) plus external shear, to different levels of complexity. We show that relaxing the isothermal constraint of the SPEMD does not lead to statistically significant different results in terms of fitting the lensing data. We thus simplified the SPEMD to a singular isothermal ellipsoid to estimate the Einstein radius of the main lens galaxy θ_E = 0.″851, the intensity and position angle of the external shear (γ,θ_γ) = (0.044, 11.°5), and we predict the lensing galaxy position to be (θ_gal,1, θ_gal,2) = (-0.″424, -0.″744) with respect to image A. We provide time delay predictions for pairs of images, assuming a plausible range of lens redshift values z_l between 0.5 and 0.9. Finally, we examine the impact on time delays of the so-called source position transformation, a family of degeneracies existing between different mass density profiles that reproduce most of the lensing observables equally well. We show that this effect contributes significantly to the time delay error budget and cannot be ignored during the modeling. This has implications for robust cosmography applications of lensed systems. GRAL 113100-441959 is the first in a series of seven new spectroscopically confirmed GLs discovered from Gaia Data Release 2.

After its formation, a young star spends some time traversing the molecular cloud complex in which it was born. It is therefore not unlikely that, well after the initial cloud collapse event which produced the star, it will encounter one or more low mass cloud fragments, which we call "cloudlets" to distinguish them from full-fledged molecular clouds. Some of this cloudlet material may accrete onto the star+disk system, while other material may fly by in a hyperbolic orbit. In contrast to the original cloud collapse event, this process will be a "cloudlet flyby" and/or "cloudlet capture" event: A Bondi-Hoyle-Lyttleton type accretion event, driven by the relative velocity between the star and the cloudlet. As we will show in this paper, if the cloudlet is small enough and has an impact parameter similar or less than GM_*/v_∞² (with v_∞ being the approach velocity), such a flyby and/or capture event would lead to arc-shaped or tail-shaped reflection nebulosity near the star. Those shapes of reflection nebulosity can be seen around several transitional disks and FU Orionis stars. Although the masses in the those arcs appears to be much less than the disk masses in these sources, we speculate that higher-mass cloudlet capture events may also happen occasionally. If so, they may lead to the tilting of the outer disk, because the newly infalling matter will have an angular momentum orientation entirely unrelated to that of the disk. This may be one possible explanation for the highly warped/tilted inner/outer disk geometries found in several transitional disks. We also speculate that such events, if massive enough, may lead to FU Orionis outbursts.

We study the photoevaporation of Jeans-unstable molecular clumps by isotropic FUV (6 eV < hν < 13.6 eV) radiation, through 3D radiative transfer hydrodynamical simulations implementing a non-equilibrium chemical network that includes the formation and dissociation of H₂. We run a set of simulations considering different clump masses (M=10 - 200 M_{\odot }) and impinging fluxes (G₀ = 2 × 10³ to 8 × 10⁴ in Habing units). In the initial phase, the radiation sweeps the clump as an R-type dissociation front, reducing the H₂ mass by a factor 40 - 90{{ per cent}}. Then, a weak (M∼eq 2) shock develops and travels towards the centre of the clump, which collapses while losing mass from its surface. All considered clumps remain gravitationally unstable even if radiation rips off most of the clump mass, showing that external FUV radiation is not able to stop clump collapse. However, the FUV intensity regulates the final H₂ mass available for star formation: for example, for G₀ < 10⁴ more than 10 per cent of the initial clump mass survives. Finally, for massive clumps ({≳ } 100 M_{\odot }) the H₂ mass increases by 25 - 50{{ per cent}} during the collapse, mostly because of the rapid density growth that implies a more efficient H₂ self-shielding.

We discuss the impact of the recent untagged analysis of B⁰ →D^* lν_barl decays by the Belle Collaboration on the extraction of the CKM element |V_cb | and provide updated SM predictions for the b → cτν observables R (D^*), P_τ, and F_L^D* . The value of |V_cb | that we find is about 2σ from the one from inclusive semileptonic B decays, and is very sensitive to the slope of the form factor at zero recoil which should soon become available from lattice calculations.

We present a sample of 21 hydrogen-free superluminous supernovae (SLSNe-I) and one hydrogen-rich SLSN (SLSN-II) detected during the five-year Dark Energy Survey (DES). These SNe, located in the redshift range 0.220 < z < 1.998, represent the largest homogeneously selected sample of SLSN events at high redshift. We present the observed g, r, i, z light curves for these SNe, which we interpolate using Gaussian processes. The resulting light curves are analysed to determine the luminosity function of SLSNe-I, and their evolutionary time-scales. The DES SLSN-I sample significantly broadens the distribution of SLSN-I light-curve properties when combined with existing samples from the literature. We fit a magnetar model to our SLSNe, and find that this model alone is unable to replicate the behaviour of many of the bolometric light curves. We search the DES SLSN-I light curves for the presence of initial peaks prior to the main light-curve peak. Using a shock breakout model, our Monte Carlo search finds that 3 of our 14 events with pre-max data display such initial peaks. However, 10 events show no evidence for such peaks, in some cases down to an absolute magnitude of <-16, suggesting that such features are not ubiquitous to all SLSN-I events. We also identify a red pre-peak feature within the light curve of one SLSN, which is comparable to that observed within SN2018bsz.

IceCube is a cubic-kilometer scale neutrino detector instrumenting a gigaton of ice at the geographic South Pole in Antarctica. On average, 8 track-like high-energy neutrino events with a high probability of being astrophysical are detected and published as alerts per year. The bright appearance of these events in the detector allow a precise pointing to their origins. This work presents a search for cosmic neutrino sources. The analysis uses high statistics archival IceCube neutrino-induced through-going muon samples to search for these sources in the vicinity of the incoming directions of the track-like high energy neutrino alert-events. The analysis searches for both steady sources emitting neutrinos over the entire uptime of IceCube, and transient sources that only temporarily produce neutrinos. This search will be applied to all historic alerts and will be automated for all future high energy track-like neutrino alerts.

We present the first numerical study of the ultraviolet dynamics of nonasymptotically free gauge-fermion theories at large number of matter fields. As test bed theories, we consider non-Abelian SU(2) gauge theories with 24 and 48 Dirac fermions on the lattice. For these numbers of flavors, asymptotic freedom is lost, and the theories are governed by a Gaussian fixed point at low energies. In the ultraviolet, they can develop a physical cutoff and therefore be trivial, or achieve an interacting safe fixed point and therefore be fundamental at all energy scales. We demonstrate that the gradient flow method can be successfully implemented and applied to determine the renormalized running coupling when asymptotic freedom is lost. Additionally, we prove that our analysis is connected to the Gaussian fixed point as our results nicely match with the perturbative beta function. Intriguingly, we observe that it is hard to achieve large values of the renormalized coupling on the lattice. This might be an early sign of the existence of a physical cutoff and imply that a larger number of flavors is needed to achieve the safe fixed point. A more conservative interpretation of the results is that the current lattice action is unable to explore the deep ultraviolet region where safety might emerge. Our work constitutes an essential step toward determining the ultraviolet fate of nonasymptotically free gauge theories.

In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.

We report the first detection of gravitational lensing due to galaxy clusters using only the polarization of the cosmic microwave background (CMB). The lensing signal is obtained using a new estimator that extracts the lensing dipole signature from stacked images formed by rotating the cluster-centered Stokes QU map cutouts along the direction of the locally measured background CMB polarization gradient. Using data from the SPTpol 500  deg2 survey at the locations of roughly 18 000 clusters with richness λ≥10 from the Dark Energy Survey (DES) Year-3 full galaxy cluster catalog, we detect lensing at 4.8σ. The mean stacked mass of the selected sample is found to be (1.43±0.40)×1014M⊙ which is in good agreement with optical weak lensing based estimates using DES data and CMB-lensing based estimates using SPTpol temperature data. This measurement is a key first step for cluster cosmology with future low-noise CMB surveys, like CMB-S4, for which CMB polarization will be the primary channel for cluster lensing measurements.

To facilitate multimessenger studies with TeV and PeV astrophysical neutrinos, the IceCube Collaboration has developed a realtime alert system for the highest confidence and best localized neutrino events. In this work we investigate the likelihood of association between realtime high-energy neutrino alerts and explosive optical transients, with a focus on core-collapse supernovae (CC SNe) as candidate neutrino sources. We report results from triggered optical follow-up observations of two IceCube alerts, IC170922A and IC171106A, with Blanco/DECam ($gri$ to 24th magnitude in $\sim6$ epochs). Based on a suite of simulated supernova light curves, we develop and validate selection criteria for CC SNe exploding in coincidence with neutrino alerts. The DECam observations are sensitive to CC SNe at redshifts $z \lesssim 0.3$. At redshifts $z \lesssim 0.1$, our selection criteria reduce background SNe contamination to a level below the predicted signal. For the IC170922A (IC171106A) follow-up observations, we expect that 12.1% (9.5%) of coincident CC SNe at $z \lesssim 0.3$ are recovered, and that on average, 0.23 (0.07) unassociated SNe in the 90% containment regions also pass our selection criteria. We find two total candidate CC SNe that are temporally coincident with the neutrino alerts, but none in the 90% containment regions, which is statistically consistent with expected rates of background CC SNe for these observations. Given the signal efficiencies and background rates derived from this pilot study, we estimate that to determine whether CC SNe are the dominant contribution to the total TeV-PeV energy IceCube neutrino flux at the $3\sigma$ confidence level, DECam observations similar to those of this work would be needed for $\sim200$ neutrino alerts, though this number falls to $\sim60$ neutrino alerts if redshift information is available for all candidates.

We study the polarization properties of extragalactic sources at 95 and 150 GHz in the SPTpol 500 deg^2 survey. We estimate the polarized power by stacking maps at known source positions, and correct for noise bias by subtracting the mean polarized power at random positions in the maps. We show that the method is unbiased using a set of simulated maps with similar noise properties to the real SPTpol maps. We find a flux-weighted mean-squared polarization fraction 〈p^2〉 = [8.9 ± 1.1] × 10^−4 at 95 GHz and [6.9 ± 1.1] × 10^−4 at 150 GHz for the full sample. This is consistent with the values obtained for a subsample of active galactic nuclei. For dusty sources, we find 95 per cent upper limits of 〈p^2〉_95 < 16.9 × 10^−3 and 〈p^2〉_150 < 2.6 × 10^−3. We find no evidence that the polarization fraction depends on the source flux or observing frequency. The 1σ upper limit on measured mean-squared polarization fraction at 150 GHz implies that extragalactic foregrounds will be subdominant to the CMB E and B mode polarization power spectra out to at least ℓ ≲ 5700 (ℓ ≲ 4700) and ℓ ≲ 5300 (ℓ ≲ 3600), respectively, at 95 (150) GHz.

Non-equilibrium conditions must have been crucial for the assembly of the first informational polymers of early life, by supporting their formation and continuous enrichment in a long-lasting environment. Here, we explore how gas bubbles in water subjected to a thermal gradient, a likely scenario within crustal mafic rocks on the early Earth, drive a complex, continuous enrichment of prebiotic molecules. RNA precursors, monomers, active ribozymes, oligonucleotides and lipids are shown to (1) cycle between dry and wet states, enabling the central step of RNA phosphorylation, (2) accumulate at the gas–water interface to drastically increase ribozymatic activity, (3) condense into hydrogels, (4) form pure crystals and (5) encapsulate into protecting vesicle aggregates that subsequently undergo fission. These effects occur within less than 30 min. The findings unite, in one location, the physical conditions that were crucial for the chemical emergence of biopolymers. They suggest that heated microbubbles could have hosted the first cycles of molecular evolution.

To understand the emergence of life, a better understanding of the physical chemistry of primordial non-equilibrium conditions is essential. Significant salt concentrations are required for the catalytic function of RNA. The separation of oligonucleotides into single strands is a difficult problem as the hydrolysis of RNA becomes a limiting factor at high temperatures. Salt concentrations modulate the melting of DNA or RNA, and its periodic modulation would enable melting and annealing cycles at low temperatures. In our experiments, a moderate temperature difference created a miniaturized water cycle, resulting in fluctuations in salt concentration, leading to melting of oligonucleotides at temperatures 20 °C below the melting temperature. This would enable the reshuffling of duplex oligonucleotides, necessary for ligation chain replication. The findings suggest an autonomous route to overcome the strand-separation problem of non-enzymatic replication in early evolution.

It is assumed that RNA played a key role in the origin of life, and the transition to more complex but more stable DNA for continuous information storage and replication requires the development of a ribonucleotide reductase to obtain the deoxyribonucleotides from ribonucleotides. This step, as well as an alternative path from abiotic molecules to DNA-based life is completely unknown. Shown here is the formation of deoxyribonucleosides under relevant prebiotic conditions in water in high regio- and stereoselectivity, from all canonical purine and pyrimidine bases, by condensation with acetaldehyde and sugar-forming precursors. Thus, a continuous path to deoxyribonucleosides, starting from simple, prebiotically available molecules has been discovered. Furthermore, the deoxyapionucleosides (DApiNA) were identified as a potential DNA progenitor. The results suggest that the DNA world evolved much earlier than previously assumed.

Protoplanetary disc surveys conducted with Atacama Large Millimetre Array (ALMA) are measuring disc radii in multiple star-forming regions. The disc radius is a fundamental quantity to diagnose whether discs undergo viscous spreading, discriminating between viscosity or angular momentum removal by winds as drivers of disc evolution. Observationally, however, the sub-mm continuum emission is dominated by the dust, which also drifts inwards, complicating the picture. In this paper we investigate, using theoretical models of dust grain growth and radial drift, how the radii of dusty viscous protoplanetary discs evolve with time. Despite the existence of a sharp outer edge in the dust distribution, we find that the radius enclosing most of the dust mass increases with time, closely following the evolution of the gas radius. This behaviour arises because, although dust initially grows and drifts rapidly on to the star, the residual dust retained on Myr time-scales is relatively well coupled to the gas. Observing the expansion of the dust disc requires using definitions based on high fractions of the disc flux (e.g. 95 per cent) and very long integrations with ALMA, because the dust grains in the outer part of the disc are small and have a low sub-mm opacity. We show that existing surveys lack the sensitivity to detect viscous spreading. The disc radii they measure do not trace the mass radius or the sharp outer edge in the dust distribution, but the outer limit of where the grains have significant sub-mm opacity. We predict that these observed radii should shrink with time.

We report the very bright detection of cold molecular gas with the IRAM NOEMA interferometer of the strongly lensed source WISE J132934.18+224327.3 at z = 2.04, the so-called Cosmic Eyebrow. This source has a similar spectral energy distribution from optical-mid/IR to submillimeter/radio but significantly higher fluxes than the well-known lensed SMG SMMJ 2135, the Cosmic Eyelash at z = 2.3. The interferometric observations unambiguously identify the location of the molecular line emission in two components, component CO32-A with {I}_CO(3-2)}=52.2+/- 0.9 Jy km s^-1 and component CO32-B with {I}_CO(3-2)}=15.7+/- 0.7 Jy km s^-1. Thus, our NOEMA observations of the CO(3-2) transition confirm the SMG-nature of WISE J132934.18+224327.3, resulting in the brightest CO(3-2) detection ever of an SMG. In addition, we present follow-up observations of the brighter component with the Green Bank Telescope (CO(1-0) transition) and IRAM 30 m telescope (CO(4-3) and [C I](1-0) transitions). The star formation efficiency of ∼100 L _⊙/(K km s^-1 pc²) is at the overlap region between merger-triggered and disk-like star formation activity and the lowest seen for lensed dusty star-forming galaxies. The determined gas depletion time ∼60 Myr, intrinsic infrared star formation SFR_IR ≈ 2000 M _⊙ yr^-1, and gas fraction M _mol/M _* = 0.44 indicate a starburst/merger-triggered star formation. The obtained data of the cold ISM—from CO(1-0) and dust continuum—indicates a gas mass μM _mol ∼ 15 × 10¹¹ M _⊙ for component CO32-A. Its unseen brightness offers us the opportunity to establish the Cosmic Eyebrow as a new reference source at z = 2 for galaxy evolution.

The upcoming radio interferometer Square Kilometre Array (SKA) is expected to directly detect the redshifted 21-cm signal from the neutral hydrogen present during the Cosmic Dawn. Temperature fluctuations from X-ray heating of the neutral intergalactic medium can dominate the fluctuations in the 21-cm signal from this time. This heating depends on the abundance, clustering, and properties of the X-ray sources present, which remain highly uncertain. We present a suite of three new large-volume, 349 Mpc a side, fully numerical radiative transfer simulations including QSO-like sources, extending the work previously presented in Ross et al. (2017). The results show that our QSOs have a modest contribution to the heating budget, yet significantly impact the 21-cm signal. Initially, the power spectrum is boosted on large scales by heating from the biased QSO-like sources, before decreasing on all scales. Fluctuations from images of the 21-cm signal with resolutions corresponding to SKA1-Low at the appropriate redshifts are well above the expected noise for deep integrations, indicating that imaging could be feasible for all the X-ray source models considered. The most notable contribution of the QSOs is a dramatic increase in non-Gaussianity of the signal, as measured by the skewness and kurtosis of the 21-cm probability distribution functions. However, in the case of late Lyman-α saturation, this non-Gaussianity could be dramatically decreased particularly when heating occurs earlier. We conclude that increased non-Gaussianity is a promising signature of rare X-ray sources at this time, provided that Lyman-α saturation occurs before heating dominates the 21-cm signal.