Fri·Jun 19, 2020Friday·June 19, 2020

1. 01*

   NLO QCD+EW predictions for $tHj$ and $tZj$ production at the LHC

   Davide Pagani🇩🇪 · Ioannis Tsinikos🇸🇪 · Eleni Vryonidou🇨🇭

   In this work we calculate the cross sections for the hadroproduction of a single top quark or antiquark in association with a Higgs ($tHj$) or $Z$ boson ($tZj$) at NLO QCD+EW accuracy. In the case of $tZj$ production we consider both the case of the $Z$ boson undecayed and the complete final state $t{\ell }^{+}{\ell }^{-}j$, including off-shell and non-resonant effects. We perform our calculation in the five-flavour-scheme (5FS), without selecting any specific production channel ($s$-, $t$- or $tW$ associated). Moreover, we provide a more realistic estimate of the theory uncertainty by carefully including the differences between the four-flavour-scheme (4FS) and 5FS predictions. The difficulties underlying this procedure in the presence of EW corrections are discussed in detail. We find that NLO EW corrections are in general within the NLO QCD theory uncertainties only if the flavour scheme uncertainty (4FS vs.~5FS) is taken into account. For the case of $t{\ell }^{+}{\ell }^{-}j$ production we also investigate differences between NLO QCD+EW predictions and NLO QCD predictions matched with a parton shower simulation including multiple photon emissions.

   hep-phhep-exJHEP(2020)·38 citations
2. 02*

   Down type iso-singlet quarks at the HL-LHC and FCC-hh

   Arpon Paul🇮🇹 · Sezen Sekmen🇰🇷 · Gokhan Unel🇺🇸

   We study the discovery potential of down type iso-singlet quarks, $D$, predicted by the $E_6$ GUT model in the $pp\to D\bar{D}\to ZZd\bar{d}\to {\ell }^{+}{\ell }^{-}{\ell }^{+}{\ell }^{-}d\bar{d}$ channel at the HL-LHC and FCC-hh colliders. The analysis is performed using a high level analysis description language and its runtime interpreter. The study shows that, using solely this channel, HL-LHC can discover $D$ quarks up to a mass of 710 GeV whereas FCC-hh up to 2430 GeV with data collected in their complete run periods.

   hep-phEPJC(2021)·9 citations
3. 03*

   Deconfinement and degrees of freedom in $pp$ and $A-A$ collisions at LHC energies

   Aditya N Mishra🇲🇽 · Guy Paić🇲🇽 · C. Pajares🇪🇸 · R. P. Scharenberg🇺🇸 · B. K. Srivastava🇺🇸

   We present the extraction of the temperature by analyzing the charged particle transverse momentum spectra in lead-lead (Pb-Pb) and proton-proton ($\mathbf{pp}$) collisions at LHC energies from the ALICE Collaboration using the Color String Percolation Model (CSPM). From the measured energy density $\mathbf{\epsilon }$ and the temperature T the dimensionless quantity $\mathbf{\epsilon }/T^4$ is obtained to get the degrees of freedom (DOF), $\mathbf{\epsilon }/T^4$ = DOF ${\pi }^2$/30. We observe for the first time a two-step behavior in the increase of DOF, characteristic of deconfinement, above the hadronization temperature at temperature $\sim$ 210 MeV for both Pb-Pb and $\mathbf{pp}$ collisions and a sudden increase to the ideal gas value of $\sim$ 47 corresponding to three quark flavors in the case of Pb-Pb collisions.

   hep-phhep-exhep-thnucl-exEPJA(2021)·18 citations
4. 04*

   Short-Range Correlations and the Nuclear EMC Effect in Deuterium and Helium-3

   E.P. Segarra🇺🇸 · J.R. Pybus🇺🇸 · F. Hauenstein🇺🇸 · D.W. Higinbotham🇺🇸 · G.A. Miller🇺🇸 · E. Piasetzky🇮🇱 · A. Schmidt🇺🇸 · M. Strikman🇺🇸 · L.B. Weinstein🇺🇸 · O. Hen🇺🇸

   The EMC effect in deuterium and helium-3 is studied using a convolution formalism that allows isolating the impact of high-momentum nucleons in short-ranged correlated (SRC) pairs. We assume that the modification of the structure function of bound nucleons is given by a universal (i.e. nucleus independent) function of their virtuality, and find that the effect of such modifications is dominated by nucleons in SRC pairs. This SRC-dominance of nucleon modifications is observed despite the fact that the bulk of the nuclear inelastic scattering cross-section comes from interacting with low-momentum nucleons. These findings are found to be robust to model details including nucleon modification function parametrization, free nucleon structure function and treatment of nucleon motion effects. While existing data cannot discriminate between such model details, we present predictions for measured, but not yet published, tritium EMC effect and tagged nucleon structure functions in deuterium that are sensitive to the neutron structure functions and bound nucleon modification functions.

   hep-phhep-exnucl-exnucl-thPRResearch(2021)·15 citations
5. 05*

   Phenomenology of the Inert Doublet Model with a global U(1) symmetry

   Adil Jueid🇰🇷 · Jinheung Kim🇰🇷 · Soojin Lee🇰🇷 · So Young Shim🇰🇷 · Jeonghyeon Song🇰🇷

   The inert doublet model is a minimal dark matter model with strong theoretical motivations, where the stability of dark matter is usually achieved by imposing a $Z_2$ parity. We promote the $Z_2$ parity into a global $U(1)$ symmetry and study its phenomenological implications. There are two characteristic features of the model: both the CP-even and CP-odd neutral inert scalars, $h_1$ and $h_2$, become DM candidates; the number of model parameters is one less than that with $Z_2$ parity. We first analyze the constraints from LEP experiments, electroweak precision tests, theoretical stability, Higgs precision data, dark matter relic density, and direct detection experiments. It is found that if the model is required to explain at least 10% of the observed relic density, the theory is extremely limited such that the dark matter mass is about $70\mathrm{GeV}$ and the charged Higgs boson is not very heavy. Focusing on this narrow parameter space, we calculate the production cross sections of almost all the possible mono-$X$ and mono-$X{X}^{\prime }$ processes at the LHC. The mono-$W\gamma$ process is shown to have high discovery potential with the help of the decay of the intermediate-mass charged Higgs boson into $W^{\pm }{h}_{1,2}$. A search strategy is designed to increase the potential discovery of the model for the mono-$W\gamma$ signal at both the HL-LHC and the FCC-hh. The optimal cut on $E_T^{\mathrm{miss}}/\sqrt{H_T}$ is suggested to maximize the signal significance, being about $0.76$ at the HL-LHC and about $7.5$ at the FCC-hh.

   hep-phhep-exPRD(2020)·19 citations
6. 06*

   Bottomonium suppression in PbPb collision at energies available at the CERN large hadron collider

   Nikhil Hatwar🇮🇳 · Captain R. Singh🇮🇳 · S. Ganesh🇮🇳 · M. Mishra🇮🇳

   We had been gradually working towards building a comprehensive quarkonia suppression formalism to explain all 3 dependencies of quarkonium suppression obtained from heavy-ion collision experiments. We present here the improved version of quarkonia suppression framework. It assumes bottomonia produced in the early stage which dissociates due to color screening, gluonic dissociation, and collisional damping in addition to the shadowing as an initial state effect. The QGP medium formed in the collisions is assumed to evolve under ($3+1$)-dimensional relativistic viscous hydrodynamics which is modeled using ECHO-QGP. This replaces the Bjorken's hydrodynamics which we had used in our earlier work where we determined the centrality and transverse momentum dependent suppression. The correlated bottom quark and bottom anti-quark could recombine in the plasma. A rate equation is employed, whose solution gives the final number of bottomonium after dissociation and recombination under $(3+1)$-dimensional expansion of the QGP medium. The Shadowing effect, which is the dominant Cold Nuclear Matter effect at LHC energies, has now been modified by employing the most recent parton distribution functions obtained from CT14 global analysis and shadowing factors from EPPS16. Using this improved formalism we determine the centrality, transverse momentum, and rapidity, dependencies of bottomonium suppression for ${\rm Y}(1S)$, and ${\rm Y}(2S)$ at the LHC's energies of $2.76$ TeV and $5.02$ TeV. We find a fairly good agreement between theoretically calculated survival probability and the measured nuclear modification factor($R_{AA}$) at the two energies.

   hep-phPRC(2021)·9 citations
7. 07*

   An Optimal Observable for Color Singlet Identification

   Andy Buckley🇬🇧 · Giuseppe Callea🇬🇧 · Andrew J. Larkoski🇺🇸 · Simone Marzani🇮🇹

   We present a novel approach to construct a color tagger, i.e. an observable that is able to discriminate the decay of a color-singlet into two jets from a two-jet background in a different color configuration. We do this by explicitly taking the ratio of the corresponding leading-order matrix elements in the soft limit, thus obtaining an observable that is provably optimal within our approximation. We call this observable the "jet color ring" and we compare its performance to other color-sensitive observables such as jet pull and dipolarity. We also assess the performance of the jet color ring in simulations by applying it to the case of the hadronic decays of a boosted Higgs boson and of an electroweak boson.

   hep-phSciPost Phys.(2020)·35 citations
8. 08*

   Analytic Continuation and Reciprocity Relation for Collinear Splitting in QCD

   Hao Chen🇨🇳 · Tong-Zhi Yang🇨🇳 · Hua Xing Zhu🇨🇳 · Yu Jiao Zhu🇨🇳

   It is well-known that direct analytic continuation of DGLAP evolution kernel (splitting functions) from space-like to time-like kinematics breaks down at three loops. We identify the origin of this breakdown as splitting functions are not analytic function of external momenta. However, splitting functions can be constructed from square of (generalized) splitting amplitudes. We establish the rule of analytic continuation for splitting amplitudes, and use them to determine the analytic continuation of certain holomorphic and anti-holomorphic part of splitting functions and transverse-momentum dependent distributions. In this way we derive the time-like splitting functions at three loops without ambiguity. We also propose a reciprocity relation for singlet splitting functions, and provide non-trivial evidence that it holds in QCD at least through three loops.

   hep-phCPC(2021)·79 citations
9. 09*

   Flavor dependence of the thermal dissociations of vector and axial-vector mesons

   Ling-feng Chen🇨🇳 · Si-Xue Qin🇨🇳 · Yu-xin Liu🇨🇳

   The in-medium behavior of ground-state $q\bar{q}$ mesons, where $q\in \{u,d,s,c\}$, in vector and axial-vector channels is studied based on the spectral analysis for mesonic correlators at finite temperature and zero chemical potential. We first compute the correlators by solving the quark gap equations and the inhomogeneous Bethe-Salpeter equations in the rainbow-ladder approximation. Using a phenomenological ansatz, the spectral functions are extracted by fitting the correlators. By analyzing the evolution of the spectral functions with the temperature, we obtain the dissociation temperatures of mesons and discuss their relations to the critical temperature of the chiral symmetry restoration. The results show a pattern of the flavor dependence of the thermal dissociation of the mesons.

   hep-phPRD(2020)·7 citations
10. 10*

    Gamow-Teller transitions and the spin EMC effect: the Bjorken sum-rule in medium

    Steven D. Bass🇵🇱

    Gamow-Teller transitions in nuclei tell us that the nucleon's axial charge $g_A^{(3)}$ is quenched in large nuclei by about 20%. This result tells us that the spin structure of the nucleon is modified in nuclei and disfavours models of the medium dependence of parton structure based only on nucleon short range correlations in nuclei. For polarized photoproduction the Gerasimov-Drell-Hearn integral is expected to be strongly enhanced in medium.

    hep-phnucl-thActa Phys.Polon.B(2021)·10 citations
11. 11*

    Looking forward to test the KOTO anomaly with FASER

    Felix Kling🇺🇸 · Sebastian Trojanowski🇬🇧

    The search for light and long-lived particles at the LHC will be intensified in the upcoming years with a prominent role of the new FASER experiment. In this study, we discuss how FASER could independently probe such scenarios relevant for new physics searches at kaon factories. We put an emphasis on the proposed explanations for the recently observed three anomalous events in the KOTO experiment. The baseline of FASER precisely corresponds to the proposed lifetime solution to the anomaly that avoids the NA62 bounds on charged kaons. As a result, the experiment can start constraining relevant models within the first few weeks of its operation. In some cases, it can confirm a possible discovery with up to 10000 spectacular high-energy events in FASER during LHC Run 3. Further complementarities between FASER and kaon factories, which employ FASER capability to study di-photon signatures, are illustrated for the model with axion-like particles dominantly coupled to $SU(2{)}_W$ gauge bosons.

    hep-phPRD(2020)·33 citations
12. 12*

    Modular Invariant Quark and Lepton Models in Double Covering of $S_4$ Modular Group

    Xiang-Gan Liu🇨🇳 · Chang-Yuan Yao🇨🇳 · Gui-Jun Ding🇨🇳

    We perform a comprehensive analysis of the homogeneous finite modular group ${\Gamma }_4^{\prime }\equiv S_4^{\prime }$ which is the double covering of $S_4$ group. The weight 1 modular forms of level 4 are constructed in terms of Dedekind eta function, and they transform as a triplet ${\hat{3}}^{\prime }$ of $S_4^{\prime }$. The integral weight modular forms until weight 6 are built from the tensor products of weight 1 modular forms. We perform a systematical classification of $S_4^{\prime }$ modular models for lepton masses and mixing with/without generalized CP, where the left-handed leptons are assigned to triplet of $S_4^{\prime }$ and right-handed charged leptons transform as singlets under $S_4^{\prime }$, and we consider both scenarios where the neutrino masses arise from Weinberg operator or type I seesaw mechanism. The phenomenological implications of the minimal models for lepton masses, mixing angles, CP violation phases and neutrinoless double decay are discussed. The $S_4^{\prime }$ modular symmetry is extended to quark sector, we present several predictive models which use nine or ten free parameters including real and imaginary parts of $\tau$ to describe quark masses and Cabibbo-Kobayashi-Maskawa mixing matrix. We give a quark-lepton unified model which can explain the flavor structure of quarks and leptons simultaneously for a common value of $\tau$.

    hep-phPRD(2021)·130 citations
13. 13*

    Dark Matter and the XENON1T electron recoil excess

    Kristjan Kannike🇪🇪 · Martti Raidal🇪🇪 · Hardi Veermäe🇪🇪 · Alessandro Strumia🇮🇹 · Daniele Teresi🇮🇹

    We show that the electron recoil excess around 2 keV claimed by the Xenon collaboration can be fitted by DM or DM-like particles having a fast component with velocity of order $\sim 0.1$. Those particles cannot be part of the cold DM halo of our Galaxy, so we speculate about their possible nature and origin, such as fast moving DM sub-haloes, semi-annihilations of DM and relativistic axions produced by a nearby axion star. Feasible new physics scenarios must accommodate exotic DM dynamics and unusual DM properties.

    hep-phastro-ph.COPRD(2020)·119 citations
14. 14*

    Asymmetric jet clustering in deep-inelastic scattering

    Miguel Arratia🇺🇸 · Yiannis Makris🇮🇹 · Duff Neill🇺🇸 · Felix Ringer🇺🇸 · Nobuo Sato🇺🇸

    We propose a new jet algorithm for deep-inelastic scattering (DIS) that accounts for the forward-backward asymmetry in the Breit frame. The Centauro algorithm is longitudinally invariant and can cluster jets with Born kinematics, which enables novel studies of transverse-momentum-dependent observables. Furthermore, we show that spherically-invariant algorithms in the Breit frame give access to low-energy jets from current fragmentation. We propose novel studies in unpolarized, polarized, and nuclear DIS at the future Electron-Ion Collider.

    hep-phnucl-exnucl-thPRD(2021)·51 citations
15. 15*

    Leptoquarks in Oblique Corrections and Higgs Signal Strength: Status and Prospects

    Andreas Crivellin🇨🇭 · Dario Mueller🇨🇭 · Francesco Saturnino🇨🇭

    Leptoquarks (LQs) are predicted within Grand Unified Theories and are well motivated by the current flavor anomalies. In this article we investigate the impact of scalar LQs on Higgs decays and oblique corrections as complementary observables in the search for them. Taking into account all five LQ representations under the Standard Model gauge group and including the most general mixing among them, we calculate the effects in $h\to \gamma \gamma$, $h\to gg$, $h\to Z\gamma$ and the Peskin-Takeuchi parameters $S$, $T$ and $U$. We find that these observables depend on the same Lagrangian parameters, leading to interesting correlations among them. While the current experimental bounds only yield weak constraints on the model, these correlations can be used to distinguish different LQ representations at future colliders (ILC, CLIC, FCC-ee and FCC-hh), whose discovery potential we are going to discuss.

    hep-phhep-exJHEP(2020)·50 citations
16. 16*

    Non-linearly realized discrete symmetries

    Saurav Das🇺🇸 · Anson Hook🇺🇸

    While non-linear realizations of continuous symmetries feature derivative interactions and have no potential, non-linear realizations of discrete symmetries feature non-derivative interactions and have a highly suppressed potential. These Goldstone bosons of discrete symmetries have a non-zero potential, but the potential generated from quantum corrections is inherently very highly suppressed. We explore various discrete symmetries and to what extent the potential is suppressed for each of them.

    hep-phJHEP(2020)·13 citations
17. 17*

    Dark matter capture in celestial objects: light mediators, self-interactions, and complementarity with direct detection

    Basudeb Dasgupta (Tata Inst., Mumbai)🇮🇳 · Aritra Gupta (ULB, Brussels)🇧🇪 · Anupam Ray (Tata Inst., Mumbai)🇮🇳

    We generalize the formalism for DM capture in celestial bodies to account for arbitrary mediator mass, and update the existing and projected astrophysical constraints on DM-nucleon scattering cross section from observations of neutron stars. We show that the astrophysical constraints on the DM-nucleon interaction strength, that were thought to be the most stringent, drastically weaken for light mediators and can be completely voided. For asymmetric DM, existing astrophysical constraints are completely washed out for mediators lighter than 5 MeV, and for annihilating DM the projected constraints are washed out for mediators lighter than 0.25 MeV. Related terrestrial direct detection bounds also weaken, but in a complementary fashion; they supersede the astrophysical capture bounds for small or large DM mass, respectively for asymmetric or annihilating DM. Repulsive self-interactions of DM have an insignificant impact on the total capture rate, but a significant impact on the black hole formation criterion. This further weakens the constraints on DM-nucleon interaction strength for asymmetric self-repelling DM, whereas constraints remain unaltered for annihilating self-repelling DM. We use the correct Hawking evaporation rate of the newly formed black hole, that was approximated as a blackbody in previous studies, and show that, despite a more extensive alleviation of collapse as a result, the observation of a neutron star collapse can probe a wide range of DM self-interaction strengths.

    hep-phastro-ph.COastro-ph.HEJCAP(2020)·104 citations
18. 18*

    Charging the Walking U(N)$\times$U(N) Higgs Theory as a Complex CFT

    Oleg Antipin🇭🇷 · Jahmall Bersini🇭🇷 · Francesco Sannino🇩🇰 · Zhi-Wei Wang🇩🇰 · Chen Zhang🇹🇼

    We apply a semi-classical method to compute the conformal field theory (CFT) data for the U(N)xU(N) non-abelian Higgs theory in four minus epsilon dimensions at its complex fixed point. The theory features more than one coupling and walking dynamics. Given our charge configuration, we identify a family of corresponding operators and compute their scaling dimensions which remarkably agree with available results from conventional perturbation theory validating the use of the state-operator correspondence for a complex CFT.

    ↳ hep-thhep-lathep-phPRD(2020)·41 citations
19. 19*

    Highly compact neutron stars and screening mechanisms. I. Equilibrium and stability

    Bernardo F. de Aguiar🇧🇷 · Raissa F. P. Mendes🇧🇷

    Modified theories of gravity that offer viable models for dark energy often rely on mechanisms that screen their effects in high density environments. From this perspective, it would appear that, once solar system constraints are satisfied, these theories would predict a trivial phenomenology for (much denser) neutron stars. In this work we explore the fact that in scalar-tensor theories the scalar degree of freedom does not couple to the mass density alone, but to the trace of the energy-momentum tensor - which can increase and eventually change sign as density and pressure build up in the core of neutron stars -, and investigate whether there could be a partial unscreening of the scalar field inside the most compact stars found in Nature. For this purpose, we construct neutron star solutions with realistic equations of state in theories with screening mechanisms and study their stability under radial perturbations. In particular, we find that stable solutions with a unscreened core can exist in chameleon models, while for the environmentally-dependent dilaton model a wealth of new, scalarized equilibrium solutions are found, some of which can be stable.

    ↳ gr-qcastro-ph.COastro-ph.HEhep-phPRD(2020)·14 citations
20. 20*

    Optical Lensing by Axion Stars: Observational Prospects with Radio Astrometry

    Anirudh Prabhu🇺🇸

    Axions and axion-like particles (ALPs) are some of the best-motivated dark matter (DM) candidates. Under certain circumstances, large axion fluctuations in the early universe can collapse to form dense configurations called axion clumps. The densest axion clumps are metastable states known as oscillons. In this paper we propose a new class of observables that exploit the axion's coupling to photons. As a result of this coupling an axion clump acts like an inhomogeneous refractive optical medium -- a lens -- that causes anomalous dispersion of incident electromagnetic waves. The dispersion of electromagnetic waves by axion clumps clearly distinguishes this lensing effect from gravitational lensing. Axion clumps passing in front of background radio sources act as lenses and lead to apparent positional shifts that can potentially be discovered by high-precision radio astrometry missions with the forthcoming Square Kilometer Array (SKA). We discuss the sensitivity of SKA to lensing effects in a variety of axion halo models. While gravitational microlensing surveys have placed strong constraints on the amount of DM that exists in the form of non-luminous astrophysical objects they have been unable to do so for objects in the mass range $[10^{-14},10^{-11}]M_{\odot }$. We find that, over a wide range of parameter space, SKA will be sensitive to optical lensing by oscillons in the mass range that is currently unconstrained by microlensing surveys.

    ↳ astro-ph.COhep-ph20 citations
21. 21*

    Axion helioscopes as solar magnetometers

    Ciaran A. J. O'Hare🇦🇺 · Andrea Caputo🇪🇸 · Alexander J. Millar🇸🇪 · Edoardo Vitagliano🇺🇸

    Axion helioscopes search for solar axions and axion-like particles via inverse Primakoff conversion in strong laboratory magnets pointed at the Sun. Anticipating the detection of solar axions, we determine the potential for the planned next-generation helioscope, the International Axion Observatory (IAXO), to measure or constrain the solar magnetic field. To do this we consider a previously neglected component of the solar axion flux at sub-keV energies arising from the conversion of longitudinal plasmons. This flux is sensitively dependent to the magnetic field profile of the Sun, with lower energies corresponding to axions converting into photons at larger solar radii. If the detector technology eventually installed in IAXO has an energy resolution better than 200 eV, then solar axions could become an even more powerful messenger than neutrinos of the magnetic field in the core of the Sun. For energy resolutions better than 10 eV, IAXO could access the inner 70% of the Sun and begin to constrain the field at the tachocline: the boundary between the radiative and convective zones. The longitudinal plasmon flux from a toroidal magnetic field also has an additional 2% geometric modulation effect which could be used to measure the angular dependence of the magnetic field.

    ↳ astro-ph.COhep-phPRD(2020)·56 citations
22. 22*

    Reacceleration of charged dark matter

    M. Kachelriess🇳🇴 · J. Tjemsland🇳🇴

    Charged particles scattering on moving inhomogenities of the magnetised interstellar medium can gain energy through the process of second-order Fermi acceleration. This energy gain depletes in turn the magnetic wave spectrum around the resonance wave-vector $k\sim 1/R_L$, where $R_L$ is the Larmor radius of the charged particle. This energy transfer can prohibit the cascading of magnetic turbulence to smaller scales, leading to a drop in the diffusion coefficient and allowing the efficient exchange of charged dark matter particles in the disk and the halo. As a result, terrestial limits from direct detection experiments apply to charged dark matter. Together with the no-observation of a drop in the diffusion coefficient, this excludes charged dark matter for $10^{3}GeV\lesssim m/q\lesssim 10^{11}GeV$, even if the charged dark matter abundance is only a small part of the total relic abundance.

    ↳ astro-ph.HEhep-phJCAP(2020)·3 citations
23. 23*

    Spectral functions of strange vector mesons in asymmetric hyperonic matter

    Amruta Mishra🇮🇳 · S. P. Misra🇮🇳

    We study the medium modifications of the spectral functions as well as production cross-sections of the strange vector mesons ($\varphi$, $K^{\ast }$ and $\overline{K^{\ast }}$) in isospin asymmetric strange hadronic matter. These are obtained from the in-medium masses of the open strange mesons and the decay widths $\varphi \to K\bar{K}$, $K^{\ast }\to K\pi$ and $\overline{K^{\ast }}\to \bar{K}\pi$ in the hadronic medium. The decay widths are computed using a field theoretic model of composite hadrons with quark/antiquark constituents, from the matrix element of the light quark-antiquark pair creation term of the free Dirac Hamiltonian between the initial and final states. The matrix element is multiplied with a coupling strength parameter for the light quark-antiquark pair creation, which is fitted to the observed vacuum decay width of the decay process. There are observed to be substantial modifications of the spectral functions as well as production cross-sections of these vector mesons due to isospin asymmetry as well as strangeness of the hadronic medum at high densities. These studies should have observable consequences, e.g. in the yield of the hidden and open strange mesons arising from the isospin asymmetric high energy heavy ion collisions at the Compressed baryonic matter (CBM) experiments at the future facility at GSI.

    ↳ nucl-thhep-phEPJA(2021)·7 citations
24. 24*

    A New Window into Black Holes

    Iosif Bena🇫🇷 · Daniel R. Mayerson🇫🇷

    We develop a formalism to compute the gravitational multipole moments and ratios of moments of non-extremal and of supersymmetric black holes in four dimensions, as well as of horizonless microstate geometries of the latter. For supersymmetric and for Kerr black holes many of these multipole moments vanish, and their dimensionless ratios are ill-defined. We present two methods to compute these dimensionless ratios, which for certain supersymmetric black holes agree spectacularly. We also compute these dimensionless ratios for the Kerr solution. Our methods allow us to calculate an infinite number of hitherto unknown parameters of Kerr black holes, giving us a new window into their physics.

    ↳ hep-thastro-ph.HEgr-qchep-phPRL(2020)·91 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.