We study the potential of deep learning to resolve the combinatorial problem in supersymmetrylike events with two invisible particles at the LHC. As a concrete example, we focus on dileptonic $t\overline{t}$ events, where the combinatorial problem becomes an issue of binary classification: pairing the correct lepton with each $b$ quark coming from the decays of the tops. We investigate the performance of a number of machine learning algorithms, including attention-based networks, which have been used for a similar problem in the fully hadronic channel of $t\overline{t}$ production, and the Lorentz Boost Network, which is motivated by physics principles. We then consider the general case when the underlying mass spectrum is unknown, and hence no kinematic end point information is available. Compared against existing methods based on kinematic variables, we demonstrate that the efficiency for selecting the correct pairing is greatly improved by utilizing deep learning techniques.

Using $2.93{\mathrm{fb}}^{-1}$ of $e^{+}{e}^{-}$ collision data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, we present a measurement of the branching fraction of the doubly Cabibbo-suppressed (DCS) decay $D^0\to K^{+}{\pi }^{-}{\pi }^0$ and a search for the DCS decay $D^0\to K^{+}{\pi }^{-}{\pi }^0{\pi }^0$. The branching fraction of $D^0\to K^{+}{\pi }^{-}{\pi }^0$ is determined to be $[3.13_{-0.56}^{+0.60}(\mathrm{stat})\pm 0.15(\mathrm{syst})]\times {10}^{-4}$. No signal is observed for $D^0\to K^{+}{\pi }^{-}{\pi }^0{\pi }^0$, and an upper limit of $3.6\times {10}^{-4}$ is set on the branching fraction at the 90% CL. We combine these results with the world-average branching fractions of their counterpart Cabibbo-favored decays to determine the ratios of the DCS over the Cabibbo-favored branching fractions, $\mathcal{B}(D^0\to K^{+}{\pi }^{-}{\pi }^0)/\mathcal{B}(D^0\to K^{-}{\pi }^{+}{\pi }^0)=(0.22\pm 0.04)\%$ and $\mathcal{B}(D^0\to K^{+}{\pi }^{-}{\pi }^0{\pi }^0)/\mathcal{B}(D^0\to K^{-}{\pi }^{+}{\pi }^0{\pi }^0)<0.40\%$ at the 90% CL which correspond to $(0.75\pm 0.14){\tan }^4{\theta }_C$ and $1.37\times {\tan }^4{\theta }_C$, respectively, where ${\theta }_C$ is the Cabibbo mixing angle.

We present a nearly reactor model independent search for sterile neutrino oscillation using 2 509 days of RENO near detector data and 180 days of NEOS data. The reactor related systematic uncertainties are significantly suppressed as both detectors are located at the same reactor complex of Hanbit Nuclear Power Plant. The search is performed by electron antineutrino (${\overline{\nu }}_e$) disappearance between six reactors and two detectors with flux-weighted baselines of 419 m (RENO) and 24 m (NEOS). A spectral comparison of the NEOS prompt-energy spectrum with a no-oscillation prediction from the RENO measurement can explore reactor ${\overline{\nu }}_e$ oscillations to sterile neutrino. Based on the comparison, we obtain a 95% C.L. excluded region of $0.1<|\mathrm{\Delta }{m}_{41}^2|<7{\mathrm{eV}}^2$. We also obtain a 68% C.L. allowed region with the best fit of $|\mathrm{\Delta }{m}_{41}^2|=2.41{\mathrm{eV}}^2$ and ${\sin }^{2}2{\theta }_{14}=0.08$ having a p-value of 8.2%. Comparisons of obtained reactor antineutrino spectra at reactor sources are made among RENO, NEOS, and Daya Bay to find a possible spectral variation.

The pole-skipping phenomenon has been proposed as a connection between chaotic properties of black hole geometries and special points where regular solutions of linearized Einstein equations at horizons have extra free parameters. In this work, we pursue the special points in the near-horizon analysis of integer spin-$\ell$ fields on the Rindler-AdS black hole. We construct linear combinations of field components to simplify coupled equations of massive fields and investigate towers of the special points along with imaginary Matsubara frequencies $i\omega =2\pi (n+1-\ell )T$ with a non-negative integer $n$ and the Hawking temperature $T$. We also propose that integrals of spin-$\ell$ bulk propagators over horizons of static black holes capture behaviors at the special points, which are generalizations of integrals of graviton propagators for shock wave geometries. Their interpretation is provided in terms of four-point amplitudes with the spin-$\ell$ exchange.

The relativistic multipole moments provide a key ingredient to characterize the gravitational field around compact astrophysical objects. They play a crucial role in the description of the orbital evolution of coalescing binary systems and encode valuable information on the nature of the binary’s components, which leaves a measurable imprint in their gravitational-wave emission. We present a new study on the multipolar structure of a class of arbitrarily spinning boson stars with quartic self-interactions in the large coupling limit, where these solutions are expected to be stable. Our results strengthen and extend previous numerical analyses, showing that even for the most compact configurations the multipolar structure deviates significantly from that of a Kerr black hole. We provide accurate data for the multipole moments as functions of the object’s mass and spin, which can be directly used to construct inspiral waveform approximants, and to perform parameter estimations and searches for boson star binaries.

We analyze the interpretation of the spherically symmetric perfect fluid solutions that admit a flat synchronization orthogonal to the fluid flow as a thermodynamic perfect fluid in local thermal equilibrium. The ideal gas sonic condition is examined for this family of metrics, and the macroscopic conditions for physical reality are accurately tested for some specific solutions.

In this paper, we investigate the thermodynamics of dyonic black holes with the presence of power Maxwell electromagnetic field in the extended phase space, which regards the cosmological constant $\mathrm{\Lambda }$ as a thermodynamic variable. For a generic power Maxwell black hole with the electric charge and magnetic charge, the equation of state is given as the function of rescaled temperature $\tilde{T}$ in terms of other rescaled variables ${\tilde{r}}_{+}$, $\tilde{q}$, and $\tilde{h}$, where $r_{+}$ is the horizon radius, $q$ is the electric charge, and $h$ is the magnetic parameter. For some values of $\tilde{q}$ and $\tilde{h}$, the phase structure of the black hole is uniquely determined. Moreover, the peculiarity of multiple temperature with some parameter configurations results in complex phase structures. Focusing on the power Maxwell Lagrangian with $\mathcal{L}(s)=s^2$, we obtain the corresponding phase diagrams in the $\tilde{h}\text{−}\tilde{q}$ plane where the critical line extends to $\tilde{h}=+\infty$. Then, we analyze the black holes’ phase structure and critical behavior and display phase transition curves with different $\tilde{h}$ in the $\tilde{q}\text{−}\tilde{T}$ plane. We also examine thermal stabilities of these black holes.

An interferometer design that cancels all displacement noises of its test masses and maintains a gravitational-wave (GW) signal by combining multiple detector signals is called a displacement noise-free interferometer (DFI). The idea has been considered previously for a laser interferometer. However, a limitation of a laser DFI is that its sensitive frequency band is too high for astrophysical GW sources, $\sim {10}^5\mathrm{Hz}$ even for a kilometer-sized interferometer. To circumvent this limitation, in this paper, we propose a neutron DFI, in which neutrons are used instead of light. Since neutrons have velocities much lower than the speed of light, the sensitive frequency band of a neutron DFI can be lowered down to $\sim {10}^{-1}\mathrm{Hz}$. Therefore, a neutron DFI can be utilized for detecting GWs that are inaccessible by an ordinary laser interferometer on the ground.

Nonthermal correction to the emission probability of particles from black holes can be obtained if the backreaction or self-gravitational effects of the emitted particles on the black hole spacetime are taken into consideration. These nonthermally emitted particles conserve the entropy of the black hole—i.e., the entropy of the system of radiated particles after complete evaporation of the black hole matches the initial entropy of the black hole. Using the nonthermal emission probability, we have determined the probability for a black hole of mass $M$ to be completely evaporated by a given number of particles $n$. This is done by first evaluating the number of possible ways in which the black hole can be evaporated by emitting $n$ number of particles, and then the total number of ways in which the black hole can be evaporated. The ratio of these two quantities gives us the desired probability. From the probability distribution, we get a displacement relation between the most probable number of particles exhausting the black hole and the temperature of the initial black hole. This relation resembles Wien’s displacement law for blackbody radiation.

We find two conditions for superradiant instability of Kerr-Newman black holes under a charged massive scalar perturbation by analyzing the asymptotic scalar potential and far-region wave function. Actually, they correspond to the condition for getting a trapping well. Also, we obtain the conditions for superradiant stability of Kerr-Newman black holes which states that there is no trapping well. The analysis is applied to Kerr black holes to find a condition for superradiant instability.

We show the existence of stable bound orbits for the massive and massless particles moving in the simplest microstate geometry spacetime in the bosonic sector of the five-dimensional minimal supergravity. In our analysis, reducing the motion of particles to a two-dimensional potential problem, we numerically investigate whether the potential has a negative local minimum.

We explore the role of redshift-space galaxy clustering data in constraining nongravitational interactions between dark energy (DE) and dark matter (DM), for which state-of-the-art limits have so far been obtained from late-time background measurements. We use the joint likelihood for prereconstruction full-shape (FS) galaxy power spectrum and postreconstruction Baryon Acoustic Oscillation (BAO) measurements from the BOSS DR12 sample, alongside Cosmic Microwave Background (CMB) data from Planck: from this dataset combination we infer $H_0=68.02_{-0.60}^{+0.49}\mathrm{km}/\mathrm{s}/\mathrm{Mpc}$ and the $2\sigma$ lower limit $\xi >-0.12$, among the strongest limits ever reported on the DM-DE coupling strength $\xi$ for the particular model considered. Contrary to what has been observed for the $\mathrm{\Lambda }\mathrm{CDM}$ model and simple extensions thereof, we find that the $\mathrm{CMB}+\mathrm{FS}$ combination returns tighter constraints compared to the $\mathrm{CMB}+\mathrm{BAO}$ one, suggesting that there is valuable additional information contained in the broadband of the power spectrum. We test this finding by running additional CMB-free analyses and removing sound horizon information, and discuss the important role of the equality scale in setting constraints on DM-DE interactions. Our results reinforce the critical role played by redshift-space galaxy clustering measurements in the epoch of precision cosmology, particularly in relation to tests of nonminimal dark sector extensions of the $\mathrm{\Lambda }\mathrm{CDM}$ model.

Recent gamma-ray and radio studies have obtained some stringent constraints on annihilating dark matter properties. However, only a few studies have focused on using x-ray data to constrain annihilating dark matter. In this article, we perform the x-ray analysis of annihilating dark matter using the data of the Omega Centauri cluster. If dark matter is the correct interpretation of the nonluminous mass component derived in the Omega Centauri cluster, the conservative lower limits of thermal dark matter mass annihilating via the ${\tau }^{+}{\tau }^{-}$, $b\overline{b}$, and $W^{+}{W}^{-}$ channels can be significantly improved to 104(43) GeV, 650 (167) GeV, and 480(137) GeV, respectively, assuming the diffusion coefficient $D_0\le {10}^{26}({10}^{27}){\mathrm{cm}}^2/\mathrm{s}$. These constraints can safely rule out the recent claims of dark matter interpretation of the gamma-ray excess and antiproton excess seen in our Galaxy. Generally speaking, the conservative lower limits obtained for nonleptophilic annihilation channels are much more stringent than that obtained by gamma-ray analysis of nearby dwarf galaxies. We anticipate that this would open a new window for constraining annihilating dark matter.

In this work, we study the jet momentum broadening in an inhomogeneous dense QCD medium. The transverse profile of this nuclear matter is described within a gradient expansion, and we focus on the leading gradient contributions. The leading parton is allowed to interact multiple times with the background through the soft gluon exchanges. We derive the associated final particle distribution using both the GLV opacity series and the BDMPS-Z formalism. We further discuss the modified factorization of the broadening process and the initial distribution of partons produced in a hard scattering, as well as its consequences for phenomenological applications in the context of heavy-ion collisions and deep inelastic scattering. Finally, we present the broadening probability (describing the final state effects) in several limiting regimes, and give its numerical estimates for phenomenologically motivated sets of parameters.

Magnetic field dependent corrections for the coupling constant of the Nambu-Jona-Lasinio model are calculated by considering the one-loop background field method. These coupling constants turn out to break chiral and flavor symmetries and they lead to a slight improvement of the numerical values of the up and down quark condensates when compared to results from lattice QCD. The corresponding magnetic field dependencies of the neutral pion and kaon masses are also presented and compared with available lattice QCD calculations. The resulting magnetic field correction to the $\eta -{\eta }^{\prime }$ mixing angle is also estimated.

The study of the dynamics of strong interactions in the high-energy regime is a core line of frontier researches at the LHC as well as at new-generation colliding facilities. Here, the enhancement of energy logarithms due to diffractive semihard final states spoils the convergence of the perturbative series in the QCD running coupling, thus calling for an improvement of the pure collinear factorization that accounts for an all-order resummation of these large logarithmic contributions. Motivated by the recent discovery that inclusive emissions of heavy-flavored particles allow for clear signals of a stabilization of high-energy resummed differential distributions under higher-order corrections and scale variations, we provide novel predictions of rapidity and azimuthal-angle observables for the inclusive hadroproduction of a light meson ($\eta$ or ${\pi }^{\pm }$) in association with a heavy-flavored hadron (${\mathrm{\Lambda }}_c$ or $b$-flavored hadron). We calculate our observables in a hybrid high-energy and collinear factorization framework, where next-to-leading Balitsky-Fadin-Kuraev-Lipatov-resummed partonic cross sections are convoluted with collinear parton distributions and fragmentation functions. We consider kinematic ranges typically covered by acceptances of LHC detectors, and new ones coming from the combined tag of an ultra-forward particle at the future Forward Physics Facility and of a central one at ATLAS via a tight timing-coincidence setup. By performing a detailed study on uncertainties associated to collinear inputs via a replica-driven analysis, as well as on ones intrinsically coming from the high-energy resummation, we highlight the challenges and the steps required to gauge the feasibility of precision studies of our processes.

We compute the matching coefficients between QCD and nonrelativistic QCD for external vector, axial-vector, scalar, and pseudoscalar currents up to three-loop order. We concentrate on the nonsinglet contributions and present precise numerical results with an accuracy of about ten digits. For the vector current the results from Marquard et al. [Phys. Rev. D 89, 034027 (2014)] are confirmed, increasing the accuracy by several orders of magnitude.

In our previous work [Phys. Rev. D 100, 101501(R) (2019)], a novel idea that the Newman-Unti-Tamburino (NUT) charge can be thought of as a thermodynamical multihair has been advocated to describe perfectly the thermodynamical character of the generic four-dimensional Taub-NUT spacetimes. According to this scheme, the Komar mass ($M$), the gravitomagnetic charge ($N$), and/or the dual (magnetic) mass ($\tilde{M}=N$), together with a new secondary hair ($J_N=MN$), namely, a Kerr-like conserved angular momentum, enter into the standard forms of the first law and Bekenstein-Smarr mass formula. Distinguished from other recent attempts, our consistent thermodynamic differential and integral mass formulas are both obtainable from a meaningful Christodoulou-Ruffini-type squared-mass formula of almost all of the four-dimensional NUT-charged spacetimes. As an excellent consequence, the famous Bekenstein-Hawking one-quarter area-entropy relation can be naturally restored not only in the Lorentzian sector and but also in the Euclidian counterpart of the generic Taub-NUT-type spacetimes without imposing any constraint condition. However, only purely electric-charged cases in the four-dimensional Einstein-Maxwell gravity theory with a NUT charge have been addressed there. In this paper, we shall follow the simple, systematic way proposed in that article to further investigate the dyonic NUT-charged case. It is shown that the standard thermodynamic relations continue to hold true provided that no new secondary charge is added; however, the so-obtained electrostatic and magnetostatic potentials are not coincident with those computed via the standard method. To rectify this inconsistence, a simple strategy is provided by further introducing two additional secondary hairs, $Q_N=QN$ and $P_N=PN$, together with their thermodynamical conjugate potentials, so that the first law and Bekenstein-Smarr mass formula are still satisfied, where $Q$ and $P$ being the electric and magnetic charges, respectively.

We briefly review the known properties of Melvin’s magnetic universe and study the propagation of test charged matter waves in this static spacetime. Moreover, the possible correspondence between the wave perturbations on the background Melvin universe and the motion of charged test particles is discussed. Next, we explore a simple scenario for turning Melvin’s static universe into one that undergoes gravitational collapse. In the resulting dynamic gravitational field, the formation of cosmic double-jet configurations is emphasized.