The singlet scalar Higgs-portal model provides one of the simplest explanations of dark matter in our Universe. Its Higgs resonant region, $m_{\mathrm{DM}}\approx m_h/2$, has gained particular attention, being able to reconcile the tension between the relic density measurement and direct detection constraints. Interestingly, this region is also preferred as an explanation of the Fermi-LAT $\gamma$-ray Galactic center excess. We perform a detailed study of this model using $\gamma$-ray data from the Galactic center and from dwarf spheroidal galaxies and combine them with cosmic-ray antiproton data from the AMS-02 experiment that shows a compatible excess. In the calculation of the relic density, we take into account effects of early kinetic decoupling relevant for resonant annihilation. The model provides excellent fits to the astrophysical data either in the case the dark matter candidate constitutes all or a subdominant fraction of the observed relic density. We show projections for future direct detection and collider experiments to probe these scenarios.

We calculate the eigenmodes of the highly improved staggered quark matrix near the chiral crossover transition in QCD with $2+1$ flavors with the aim to gain more insights into its temperature dependence. On performing the continuum extrapolation, we do not observe any gap opening up in the infrared part of the eigenvalue density of the QCD Dirac operator; instead we observe a peak. The existence of the peak and oscillations of the infrared eigenmodes can be understood in terms of an interacting ensemble of instantons. From the properties of the continuum extrapolated eigenspectrum we further show that the anomalous $U_A(1)$ part of the chiral symmetry is not effectively restored simultaneously along with its nonsinglet counterpart. We provide an explanation for this observation, further showing interesting connections between the anomalous $U_A(1)$ restoration and the change in the infrared part of the eigenvalue distribution.

In this paper, a comprehensive analysis of the dynamical evolution of quark-gluon plasma (QGP) is presented. A perturbation approach is utilized to obtain the longitudinal and radial evolution of the fluid. The transverse fluid velocity and acceleration parameter are determined based on the influence of the generalized Bjorken model. By employing this approach, the fluid velocities, acceleration parameter, and energy density are derived. These quantities offer valuable insights into the space-time evolution of the quark-gluon plasma in heavy-ion collisions. To accurately assess these quantities, only four free parameters, namely $A_1$, $A_2$, $q$, and $\widehat{{\epsilon }_0}$, need to be introduced, which are the only free parameters in the model. The transverse expansion of the quark-gluon plasma is characterized by two parameters, namely $q$ and $\widehat{{\epsilon }_0}$, which are introduced by Gubser’s solution. Gubser’s solutions are utilized as initial conditions at ${\tau }_0$ to determine the energy density and the radial fluid velocity. Our approach, therefore, involves exploring the parameter space of these two parameters in order to find suitable values that can simulate heavy-ion collisions. It has been observed that selecting $\widehat{{\epsilon }_0}=1500$ and $1/q=6.4\mathrm{fm}$ produces reasonable results. Furthermore, a comparison is made between the radial velocity and correction energy density obtained from our model and those obtained from the Gubser model. In addition, we ascertain the acceleration parameter of the fluid and the distribution of longitudinal energy density, which manifests as a Gaussian distribution. The expansion of the quark-gluon plasma in the longitudinal direction is distinguished by two additional parameters, denoted as $A_1$ and $A_2$. Our methodology facilitates the derivation of equations for fluid velocities and energy densities in both the transverse and longitudinal directions of the dense and heated quark matter.

We determine $|V_{cb}|$ from the inclusive semileptonic decay width of the $B$ meson with the known ${\mathrm{N}}^3\mathrm{LO}$ perturbative coefficients for the first time in the $\overline{\mathrm{MS}}$ mass scheme. We make use of a recently developed method, dual-space-renormalon-subtraction method, to separate and subtract the order ${\mathrm{\Lambda }}_{\mathrm{QCD}}^2/m_b$ infrared renormalon. This allows us to perform the analysis accurately in the $\overline{\mathrm{MS}}$ mass scheme, in which otherwise the perturbative series does not converge well up to the currently calculated perturbation order. Our result reads $|V_{cb}|=0.0415({}_{-12}^{+10})$, which is consistent with the previous results based on other mass schemes and shows an independent cross-check of the current theoretical evaluation of the inclusive decay width.

Inspired by the observations of $T_{c\overline{s}0}^a(2900{)}^0$ and $T_{c\overline{s}0}^a(2900{)}^{++}$ by LHCb Collaboration, we perform a systematical investigation of the charmed-strange pentaquark system by using the resonance group method in the quark delocalization color screening model. The present estimations indicate the existence of two bound states with $I(J^P)$ to be $\frac{1}{2}({\frac{5}{2}}^{-})$ and $\frac{3}{2}({\frac{5}{2}}^{-})$, and the masses are predicted to be 3392 and 3307 MeV, respectively. Moreover, three resonance states are also predicted in the present work. The ${\mathrm{\Sigma }}_c{K}^{*}$ resonance with $I(J^P)=\frac{1}{2}({\frac{1}{2}}^{-})$ could be observed in the $N{D}_s^{*}$, ${\mathrm{\Lambda }}_c{K}^{*}$ and ${\mathrm{\Sigma }}_{c}K$ channels, the mass and width are estimated to be (3342–3346) MeV and 25.5 MeV, respectively. The ${\mathrm{\Sigma }}_c{K}^{*}$ resonance with $I(J^P)=\frac{1}{2}({\frac{3}{2}}^{-})$ is available only in the ${\mathrm{\Sigma }}_c^{*}K$ channel, and the resonance parameters are evaluated to be $m_R=3333\mathrm{MeV}$ and ${\mathrm{\Gamma }}_R=3.3\mathrm{MeV}$. We also find a very narrow $\mathrm{\Delta }{D}_s^{*}$ resonance state in the ${\mathrm{\Sigma }}_{c}K$ channel with $I(J^P)=\frac{3}{2}({\frac{1}{2}}^{-})$ and $m_R=3343\mathrm{MeV}$. These predictions of the charmed-strange pentaquark may be accessible by further experimental measurements in Belle II and LHCb Collaborations, and the corresponding experimental measurements can in turn be a good test of present estimations.

We have estimated the electrical and thermal conductivity of a hadron resonance gas (HRG) for a time-varying magnetic field, which is also compared with constant and zero magnetic field cases. Considering the exponential decay of electromagnetic fields with time, a kinetic theory framework can provide the microscopic expression of electrical conductivity and thermal conductivity related to baryon current in terms of relaxation and decay times. In the absence of the magnetic field, only a single timescale appears, and in the finite magnetic field case, their expressions carry two timescales—relaxation time and cyclotron time period. Estimating the conductivities for HRG matter in three cases—zero, constant, and time-varying magnetic fields, we have studied the validity of the Wiedemann–Franz law. We noticed that at a high-temperature domain, the ratio saturates at a particular value, which may be considered as Lorenz number of the hadron resonance gas. With respect to the saturation values, the deviation of the Wiedemann–Franz law has been quantified at the low-temperature domain. For the first time, the present work sketches this quantitative deviation of the Wiedemann–Franz law for hadron resonance gas at a constant and a time-varying magnetic field.

We perform a combined study of the two hadronic decays $D^{+}\to K^{-}{\pi }^{+}{\pi }^{+}$ and $D_s^{+}\to K^{+}{K}^{+}{\pi }^{-}$ using a detailed analysis of the semileptonic decays $D^{+}\to K^{-}{\pi }^{+}{\ell }^{+}{\nu }_{\ell }$ ($\ell =e$, $\mu$) thanks to the high-statistics dataset provided by the BESIII Collaboration. We propose simple and suitable amplitude parametrizations of the studied reactions that shall be of interest to experimentalists for upcoming analyses. These new parametrizations are based on the naïve-factorization hypothesis and the description of the resulting matrix elements in terms of well-known hadronic form factors, with special emphasis on the $K\pi$ scalar and vector cases. Such form factors account for two-body final-state interactions which fulfill analyticity, unitarity, and chiral symmetry constraints. As a result of our study, we find that the $P$-wave contribution fits nicely within the naïve-factorization approach, whereas the $S$-wave contribution requires complex Wilson coefficients that hint for possibly genuine three-body nonfactorizable effects. Our hypothesis is further supported by the examination of $D_s^{+}\to K^{+}{K}^{+}{\pi }^{-}$ decays, where we achieve a description in overall good agreement with data.

The elastic and inelastic neutral current $\nu$ ($\overline{\nu }$) scattering off the polarized nucleon is discussed. The inelastic scattering concerns the single-pion production process. We show that the spin asymmetries’ measurement can help to distinguish between neutrino and antineutrino neutral current scattering processes. The spin asymmetries also encode information about a type of target. Eventually, detailed studies of the inelastic spin asymmetries can improve understanding of the resonant-nonresonant pion production mechanism.

Investigations of dense neutrino cloud evolution through quantum kinetic equations led to the possibility of “fast flavor” (FF) processes. It is shown here that the usual quantum kinetic equations, while signaling the instabilities that make some instances of FF possible, are being erroneously interpreted. Approaching the subject directly from the quantum field theory that defines the standard model shows the computational structures in most of the recent FF literature to be completely invalid. Our revisions also underlie what promise to be new early Universe applications and a general result for relic supernova neutrinos that could be tested as a feature of the diffuse neutrino spectrum.

Precision measurements of the semileptonic decays $D_s^{+}\to \eta e^{+}{\nu }_e$ and $D_s^{+}\to {\eta }^{\prime }{e}^{+}{\nu }_e$ are performed with $7.33{\mathrm{fb}}^{-1}$ of $e^{+}{e}^{-}$ collision data collected at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector. The branching fractions obtained are $\mathcal{B}(D_s^{+}\to \eta e^{+}{\nu }_e)=(2.255\pm 0.039_{\mathrm{stat}}\pm 0.051_{\mathrm{syst}})\%$ and $\mathcal{B}(D_s^{+}\to {\eta }^{\prime }{e}^{+}{\nu }_e)=(0.810\pm 0.038_{\mathrm{stat}}\pm 0.024_{\mathrm{syst}})\%$. Combining these results with the $\mathcal{B}(D^{+}\to \eta e^{+}{\nu }_e)$ and $\mathcal{B}(D^{+}\to {\eta }^{\prime }{e}^{+}{\nu }_e)$ obtained from previous BESIII measurements, the $\eta -{\eta }^{\prime }$ mixing angle in the quark flavor basis is determined to be ${\varphi }_{\mathrm{P}}=(40.0\pm {2.0}_{\mathrm{stat}}\pm {0.6}_{\mathrm{syst}})°$. Moreover, from the fits to the partial decay rates of $D_s^{+}\to \eta e^{+}{\nu }_e$ and $D_s^{+}\to {\eta }^{\prime }{e}^{+}{\nu }_e$, the products of the hadronic transition form factors $f_{+}^{{\eta }^{(\prime )}}(0)$ and the modulus of the $c\to s$ Cabibbo-Kobayashi-Maskawa matrix element $|V_{cs}|$ are determined by using different hadronic transition form factor parametrizations. Based on the two-parameter series expansion, the products $f_{+}^{\eta }(0)|V_{cs}|=0.4519\pm 0.0071_{\mathrm{stat}}\pm 0.0065_{\mathrm{syst}}$ and $f_{+}^{{\eta }^{\prime }}(0)|V_{cs}|=0.525\pm 0.024_{\mathrm{stat}}\pm 0.009_{\mathrm{syst}}$ are extracted. All results determined in this work supersede those measured in the previous BESIII analyses based on the $3.19{\mathrm{fb}}^{-1}$ subsample of data at 4.178 GeV.

The holographic gauge/gravity duality provides an explicit reduction of quantum field theory (QFT) calculations in the semiclassical large-$N$ limit to sets of “gravitational” differential equations whose analysis can reveal all details of the spectra of thermal QFT correlators. We argue that in certain cases, a complete reconstruction of the spectrum and of the corresponding correlator is possible from only the knowledge of an infinite, discrete set of pole-skipping points traversed by a single (hydrodynamic) mode computed in a series expansion in an inverse number of spacetime dimensions. Conceptually, this reduces the computation of a QFT correlator spectrum to performing a set of purely algebraic manipulations. With the help of the pole-skipping analysis, we also uncover a novel structure underpinning the coefficients that enter the hydrodynamic dispersion relations.

In a recent paper [Phys. Rev. D 100, 024019 (2019)] the authors calculated the bending angle of light in Schwarzschild-de Sitter (SdS) spacetime and also in the static and spherically symmetric vacuum solution of Weyl’s conformal gravity, which is sometimes referred to as the Mannheim-Kazanas (MK) spacetime. To do this they used the standard Weinberg analysis which is normally used to calculate the bending angle of light in asymptotically flat spacetimes, but limited the integration to the position of the cosmological horizon in these spacetimes. In this paper we make some comments about the bending angle formulas obtained in these spacetimes. We point out that in the case of the MK spacetime this would still lead to an unphysical term in their formula for the deflection angle, which also occurred in previous light bending formulas for this spacetime based on similar analysis.

We calculate the spin-orbit corrections to the loss of angular momentum in a two-body scattering at third post-Minkowskian order, $\mathcal{O}(G^3)$, from scattering amplitudes using the eikonal operator. These results include effects linear in spin, are valid for generic spin orientations, and are presented in a manifestly Poincaré covariant way. We include both radiative losses, by means of the leading-order gravitational waveform, and static losses, by means of the appropriate $-i0$ prescription in the leading soft graviton theorem, finding agreement with known results in the post-Newtonian limit.

4D $\mathcal{N}=2$ superconformal field theories and their invariants can be often enriched by nonlocal Bogomol’nyi-Prasad-Sommerfield operators. In this paper we study the flavored Schur index of several types of $\mathcal{N}=2$ superconformal field theories with and without line operators, using a series of new integration formula of elliptic functions and Eisenstein series. We demonstrate how to evaluate analytically the Schur index for a series of $A_2$ class-$\mathcal{S}$ theories and the $\mathcal{N}=4$ $SO(7)$ theory. For all $A_1$ class-$\mathcal{S}$ theories we obtain closed-form expressions for $SU(2)$ Wilson line index, and ’t Hooft line index in some simple cases. We also observe the relation between the line operator index with the characters of the associated chiral algebras. The Wilson line index for some other low rank gauge theories is also studied.

Eccentric compact binary mergers are significant scientific targets for current and future gravitational wave observatories. To detect and analyze eccentric signals, there is an increasing effort to develop waveform models, numerical relativity simulations, and parameter estimation frameworks for eccentric binaries. Unfortunately, current models and simulations use different internal parametrizations of eccentricity in the absence of a unique natural definition of eccentricity in general relativity, which can result in incompatible eccentricity measurements. In this paper, we adopt a standardized definition of eccentricity and mean anomaly based solely on waveform quantities and make our implementation publicly available through an easy-to-use python package, gw_eccentricity. This definition is free of gauge ambiguities, has the correct Newtonian limit, and can be applied as a postprocessing step when comparing eccentricity measurements from different models. This standardization puts all models and simulations on the same footing and enables direct comparisons between eccentricity estimates from gravitational wave observations and astrophysical predictions. We demonstrate the applicability of this definition and the robustness of our implementation for waveforms of different origins, including post-Newtonian theory, effective-one-body, extreme mass ratio inspirals, and numerical relativity simulations. We focus on binaries without spin precession in this work, but possible generalizations to spin-precessing binaries are discussed.

Pulsar timing arrays (PTAs) provide a way to detect gravitational waves (GWs) at nanohertz frequencies. To ensure the detection of GWs, observational data must exhibit the Hellings-Downs angular correlation. It is also known that PTAs can probe ultralight dark matter. This paper considers possible contamination of the Hellings-Downs angular correlation by the ultralight dark matter. We find that ultralight vector dark matter can give rise to the deformation of the Hellings-Downs correlation curve. Thus, the Hellings-Downs correlation curve could contain information on ultralight dark matter with a spin.

Numerical simulations of merging compact objects and their remnants form the theoretical foundation for gravitational wave and multimessenger astronomy. While Cartesian-coordinate-based adaptive mesh refinement is commonly used for simulations, spherical-like coordinates are more suitable for nearly spherical remnants and azimuthal flows due to lower numerical dissipation in the evolution of fluid angular momentum, as well as requiring fewer numbers of computational cells. However, the use of spherical coordinates to numerically solve hyperbolic partial differential equations can result in severe Courant-Friedrichs-Lewy (CFL) stability condition time step limitations, which can make simulations prohibitively expensive. This paper addresses this issue for the numerical solution of coupled spacetime and general relativistic magnetohydrodynamics evolutions by introducing a double fast Fourier transform (FFT) filter and implementing it within the fully message passing interface (mpi)-parallelized sphericalnr framework in the einstein toolkit. We demonstrate the effectiveness and robustness of the filtering algorithm by applying it to a number of challenging code tests, and show that it passes these tests effectively, demonstrating convergence while also increasing the time step significantly compared to unfiltered simulations.

The existence of a cosmic neutrino background has been inferred indirectly from cosmological surveys through its effect on the linear-theory evolution of primordial density perturbations, as well as from measurements of the primordial abundances of light elements. Constraints on the masses of the three neutrino species imply that at least two of them move nonrelativistically today. As a consequence, nonlinear evolution of density perturbations results in the formation of neutrino halos around dark matter halos. We study whether these neutrino halos can be detected in the foreseeable future through measurements of weak gravitational lensing of the cosmic microwave background, thus providing, possibly, the first beyond-linear-theory signature of cosmic neutrinos.

In recent years, the field of Gravitational Wave Astronomy has flourished. With the advent of more sophisticated ground-based detectors and space-based observatories, it is anticipated that Gravitational Wave events will be detected at a much higher rate in the near future. One of the future data analysis challenges is performing robust statistical inference in the presence of detector noise transients or nonstationarities, as well as in the presence of stochastic Gravitational Wave signals of possible astrophysical and/or cosmological origin. The incomplete knowledge of the total noise of the observatory can introduce challenges in parameter estimation of detected sources. In this work, we propose a heavy-tailed, Hyperbolic likelihood, based on the Generalized Hyperbolic distribution. With the Hyperbolic likelihood we obtain a robust data analysis framework against data outliers, noise nonstationarities, and possible inaccurate modeling of the noise power spectral density. We apply this methodology to examples drawn from gravitational wave astronomy, and in particular to synthetic data sets from the planned LISA mission.