Tue·Mar 28, 2023Tuesday·March 28, 2023

1. 01*

   Collinearly Enhanced Realizations of the YFS MC Approach to Precision Resummation Theory

   S. Jadach (1, a)🇵🇱 · B.F.L. Ward (2)🇺🇸 · Z. A. Was (1) ((1) Institute of Nuclear Physics, Krakow, PL, (2) Baylor University, Waco, TX, USA, (a) Deceased)🇵🇱

   We extend the YFS IR resummation theory to include all of the attendant collinear contributions which exponentiate. This improves the original YFS formulation in which only a part of these contributions was exponentiated. We show that the new resummed contributions agree with known results from the collinear factorization approach and we argue that they improve the attendant precision tag for a given level of exactness in the respective YFS hard radiation residuals.

   hep-phPLB(2024)·12 citations
2. 02*

   Systematic analysis of (multi)strange hadron ${\mathbf{p}}_{\mathbf{t}}$ spectra from small collision systems at the large hadron collider

   Thomas A. Trainor🇺🇸

   Small collision systems, e.g. $p$-$p$ and $p$-Pb collisions, comprise a potential reference for more-central A-A collisions with regard to production (or not) of a thermalized quark-gluon plasma (QGP). Small systems with low particle densities should evolve according to simple QCD mechanisms including projectile-nucleon dissociation and dijet production. But it is now claimed that QGP may appear even in $p$-$p$ collisions based on apparent evidence for radial flow from shape evolution of $p_t$ spectra and from variation of total yields for strange and multistrange hadrons relative to statistical models. The present study confronts such arguments with a detailed analysis of $p_t$ spectra for strange and multistrange hadrons from 5 TeV $p$-Pb collisions and 13 TeV $p$-$p$ collisions via a two-component model (TCM) of hadron production. Based on previous analysis of lighter hadrons the TCM accurately predicts spectra for Cascade and Omega hadrons. Significant results include multistrange hadron spectra dominated by jet fragments, variation of strange-hadron abundances exaggerated by certain plot formats and spectrum extrapolations, and detailed relations between ensemble-mean ${\bar{p}}_t$ variation with event charge density and small shifts of jet fragment distributions on $p_t$. Within a TCM context $p$-$p$ and $p$-Pb collision systems with comparable jet contributions are found to be equivalent within data uncertainties. Attribution of certain data features to radial flow is doubtful.

   hep-ph5 citations
3. 03*

   Chiral symmetry breaking and the masses of hadrons: a review

   Su Houng Lee🇰🇷

   The masses of hadrons in the vacuum, where the chiral symmetry is restored, and in the medium are in general different even when the changes in the order parameters of chiral symmetry are the same. Here, we first discuss the relation between the hadron masses and the chiral symmetry breaking in approaches based on operator product expansion (OPE). We then discuss what additional changes occur to the hadron masses when going from the chiral symmetry restored vacuum to nuclear medium and/or finite temperature. The work will highlight how we can identify the effects of chiral symmetry restoration from experimental observations.

   hep-phnucl-exnucl-thSymmetry(2023)·18 citations
4. 04*

   The Invisible Dilaton

   Philippe Brax🇫🇷 · Clare Burrage🇬🇧 · Jose A.R. Cembranos🇪🇸 · Patrick Valageas🇫🇷

   We analyse the dynamics of a light scalar field responsible for the $\mu$ term of the Higgs potential and coupled to matter via the Higgs-portal mechanism. We find that this dilaton model is stable under radiative corrections induced by the standard model particle masses. When the background value of the scalar field is stabilised at the minimum of the scalar potential, the scalar field fluctuations only couple quadratically to the massive fields of the standard model preventing the scalar direct decay into standard model particles. Cosmologically and prior to the electroweak symmetry breaking, the scalar field rolls down along its effective potential before eventually oscillating and settling down at the electroweak minimum. These oscillations can be at the origin of dark matter due to the initial misalignment of the scalar field compared to the electroweak minimum, and we find that, when the mass of the scalar field is less than the eV scale and acts as a condensate behaving like dark matter on large scales, the scalar particles cannot thermalise with the standard model thermal bath. As matter couples in a composition-dependent manner to the oscillating scalar, this could lead to a violation of the equivalence principle aboard satellites such as the MICROSCOPE experiment and the next generation of tests of the equivalence principle. Local gravitational tests are evaded thanks to the weakness of the quadratic coupling in the dark matter halo, and we find that, around other sources, these dilaton models could be subject to a screening akin to the symmetron mechanism.

   hep-phastro-ph.COgr-qcPRD(2023)·12 citations
5. 05*

   Central exclusive diffractive $p$ $\bar{p}$ production in the Regge-eikonal model in the "scalar'' proton approximation

   R.A. Ryutin🇷🇺

   Central exclusive diffractive production (CEDP) of proton anti-proton pairs was calculated in the Regge-eikonal approach taking into account continuum and possible $f_0(2100)$ resonance. We use the simple model with the ``scalar'' proton. Data from ISR and STAR were analysed and compared with theoretical description. Some predictions for the LHC at 13~TeV are also presented. We discuss shortly possible nuances, problems and prospects of investigations of this process at present and future hadron colliders.

   hep-phhep-exEPJC(2023)·2 citations
6. 06*

   Experimental observation of a Rindler horizon

   Morgan H. Lynch🇰🇷

   In this manuscript we confirm the presence of a Rindler horizon at CERN-NA63 by exploring its thermodynamics induced by the Unruh effect in their high energy channeling radiation experiments. By linking the entropy of the emitted radiation to the photon number, we find the measured spectrum to be a simple manifestation of the second law of Rindler horizon thermodynamics and thus a direct measurement of the recoil Fulling-Davies-Unruh (FDU) temperature. Moreover, since the experiment is born out of an ultra-relativistic positron, and the FDU temperature is defined in the proper frame, we find that temperature boosts as a length and thus fast objects appear colder. The spectrum also provides us with a simple setting to measure fundamental constants, and we employ it to measure the positron mass.

   hep-phgr-qchep-thGen.Rel.Grav.(2025)·6 citations
7. 07*

   The $Z$ resonance, inelastic dark matter, and new physics anomalies in the Simple Extension of the Standard Model (SESM) with general scalar potential

   Wenxing Zhang🇨🇳 · Tianjun Li🇨🇳 · Xiangwei Yin🇨🇳

   We consider the generic scalar potential with CP-violation, and study the $Z$ resonance and inelastic dark matter in the Simple Extension of the Standard Model (SESM), which can explain the dark matter as well as new physics anomalies such as the B physics anomalies and muon anomalous magnetic moment, etc. With the new scalar potential terms, we obtain the mass splittings for the real and imaginary parts of scalar fields. And thus we can have the DM co-annihilation process mediated by $Z$ boson, which couples exclusively to the CP-even and CP-odd parts of scalar fields. This is a brand new feature compared to the previous study. For the CP conserving case, we present the viable parameter space for the Higgs and $Z$ resonances, which can explain the B physics anomalies, muon anomalous magnetic moment, and dark matter relic density, as well as evade the constraint from the XENON1T direct detection simultaneously. For the CP-violating case, we consider the inelastic dark matter, and study four concrete scenarios for the inelastic DM-nucleon scatterings mediated by the Higgs and $Z$ bosons in details. Also, we present the benchmark points which satisfy the aforementioned constraints. Furthermore, we investigate the constraints from the dark matter-electron inelastic scattering processes mediated by the Higgs and $Z$ bosons in light of the XENONnT data. We show that the constraint on the $Z$ mediated process is weak, while the Higgs mediated process excludes the dark matter with mass around several MeV.

   hep-phEPJC(2023)·1 citation
8. 08*

   Decay of ALP Condensates via Gravitation-Induced Resonance

   Robert Brandenberger🇨🇦 · Vahid Kamali🇨🇦 · Rudnei O. Ramos (McGill)🇧🇷

   Oscillating scalar field condensates induce small amplitude oscillations of the Hubble parameter which can induce a decay of the condensate due to a parametric resonance instability [1]. We show that this instability can lead to the decay of the coherence of the condensate of axion-like particle (ALP) fields during the radiation phase of standard cosmology for rather generic ALP parameter values, with possible implications for certain experiments aiming to search for ALP candidates. As an example, we study the application of this instability to the QCD axion. We also study the magnitude of the induced entropy fluctuations.

   hep-phastro-ph.COgr-qchep-thJCAP(2023)·11 citations
9. 09*

   Sensitivity of anomalous quartic gauge couplings via tri-photon production at FCC-hh

   A. Senol🇹🇷 · H. Denizli🇹🇷 · C. Helveci🇹🇷

   A direct investigation of the self-couplings of gauge bosons, completely described by the non-Abelian gauge symmetry of the Standard Model, is extremely valuable in understanding the gauge structure of the SM. Any deviation from the SM predictions on gauge boson self-coupling is to give a hint at the existence of a new physics beyond the SM, which is defined with a modification of the self-interactions using an effective field theory approach. In this paper, we present a detailed Monte Carlo study searching for anomalous quartic gauge dimension-8 couplings related to $\gamma \gamma \gamma \gamma$ and $\gamma \gamma \gamma Z$ vertices at the future hadron-hadron collider (FCC-hh) via tri-photon production at a 100 TeV center of mass energy with an integrated luminosity L${}_{int}$=30 ab${}^{-1}$. Events that have been parton showered and include detector effects are analyzed with a Toolkit for Multivariate Data Analysis (TMVA) using a boosted decision tree to help distinguish between signal and background events to achieve the best sensitivities on anomalous quartic gauge couplings. Our obtained results reveal that the limits on anomalous quartic gauge couplings $f_{T8}/{\Lambda }^4$ and $f_{T9}/{\Lambda }^4$ at 95\% C.L. without systematic errors are about three orders of magnitude stronger compared to the best current experimental limits reported by the ATLAS collaboration at the LHC. Considering a realistic systematic uncertainty such as 10\% from possible experimental sources, our obtained limits of anomalous quartic couplings get worse by about one order of magnitude compared to those without systematic uncertainty but are still two orders of magnitude better than those recently reported by ATLAS.

   hep-phNPB(2024)·8 citations
10. 10*

    Flavor dependence of jet quenching in heavy-ion collisions from a Bayesian analysis

    Shan-Liang Zhang🇨🇳 · Enke Wang🇨🇳 · Hongxi Xing🇨🇳 · Ben-Wei Zhang🇨🇳

    We investigate the flavor dependence of jet quenching, by performing a systematic analysis of medium modifications on the inclusive jet, $\gamma$+jet, and $b$-jet in Pb+Pb collisions at the LHC. Our results from MadGraph+PYTHIA exhibit excellent agreement with experimental measurements of the inclusive jet, $\gamma$+jet and $b$-jet simultaneously in p+p collisions. We then utilize a Bayesian data-driven method to extract systematically the flavor-dependent jet energy loss distributions from experimental data, where the gluon, light quark and $b$-quark initiated energy loss distributions are well constrained and satisfy the predicted flavor hierarchy of jet quenching, i.e. $⟨\Delta E_g⟩>⟨\Delta E_q⟩>⟨\Delta E_b⟩$. It is shown that the quark-initiated jet energy loss distribution shows weaker centrality and $p_{\text{T}}$ dependence than the gluon-initiated one. We demonstrate the impacts of the slope of initial spectra, color-charge as well as parton mass dependent jet energy attenuation on the $\gamma /b$-jet suppression observed in heavy-ion collisions.

    hep-phhep-exPLB(2024)·21 citations
11. 11*

    A model with vectorlike fermions and $U(1{)}_X$ symmetry: CKM unitarity, $b\to s$ transitions, and prospect at Belle II

    Sang Quang Dinh🇻🇳 · Hieu Minh Tran🇻🇳

    The updated analysis of the LHCb Collaboration on the lepton flavor violation suggests that the new physics should couple to muons and electrons with comparable magnitudes, resulting in the anomalies in both rare decay channels, $b\to s{\mu }^{+}{\mu }^{-}$ and $b\to s{e}^{+}{e}^{-}$. Meanwhile, the recent result of the Muon $g-2$ experiment with higher precision has increased the existing tension with the standard model prediction. In this paper, we consider an extension of the standard model with a new sector consisting of vectorlike fermions and two scalar charged under an extra $U(1{)}_X$ gauge symmetry. The exotic Yukawa interactions in the this model lead to the quark mixing responsible for the additional contributions to the flavor changing neutral currents in $B$-meson decays, and solve the muon $g-2$ discrepancy. We derive the analytic expression of the new physics contributions to the Wilson coefficient $C_7$ in the effective Hamiltonian, and point out that the CKM unitarity violation can be explained within this context. By calculating the branching ratio of the inclusive radiative $B$ decay, the impact of current experimental data of the $b\to s\gamma$ transition on the model and the future prospect at the Belle II experiment are investigated. Taking into account the current data on the muon anomalous magnetic moment, the CKM unitarity violation, the constraints on the flavor observables relevant to the $b\to s$ transitions, the LHC searches for vectorlike quarks, and the perturbation limits of the couplings, the viable parameter regions of the model are identified.

    hep-phNPB(2023)·6 citations
12. 12*

    Hybrid scoto/seesaw: flavour and dark matter

    D.M. Barreiros🇵🇹 · H.B. Câmara🇵🇹 · F.R. Joaquim🇵🇹

    We propose a model based on the interplay between the type-II seesaw and scotogenic neutrino mass generation mechanisms. The setup features a ${\mathbb{Z}}_8$ discrete flavour symmetry which is broken down to a residual ${\mathbb{Z}}_2$ responsible for stabilising dark matter. A singlet scalar field is introduced to implement spontaneous CP violation. The effective neutrino mass matrix two-texture zero structure leads to sharp neutrino sector predictions. We analyse the constraints imposed on the model by current and future charged lepton flavour violation experiments. This framework provides two viable dark matter candidates, scalar or fermion. We investigate the scalar dark matter scenario considering relic density, direct-detection and collider constraints.

    hep-phPoS(2024)·0 citations
13. 13*

    Exploring QCD matter in extreme conditions with Machine Learning

    Kai Zhou🇩🇪 · Lingxiao Wang🇩🇪 · Long-Gang Pang🇨🇳 · Shuzhe Shi🇺🇸

    In recent years, machine learning has emerged as a powerful computational tool and novel problem-solving perspective for physics, offering new avenues for studying strongly interacting QCD matter properties under extreme conditions. This review article aims to provide an overview of the current state of this intersection of fields, focusing on the application of machine learning to theoretical studies in high energy nuclear physics. It covers diverse aspects, including heavy ion collisions, lattice field theory, and neutron stars, and discuss how machine learning can be used to explore and facilitate the physics goals of understanding QCD matter. The review also provides a commonality overview from a methodology perspective, from data-driven perspective to physics-driven perspective. We conclude by discussing the challenges and future prospects of machine learning applications in high energy nuclear physics, also underscoring the importance of incorporating physics priors into the purely data-driven learning toolbox. This review highlights the critical role of machine learning as a valuable computational paradigm for advancing physics exploration in high energy nuclear physics.

    hep-phastro-ph.HEhep-exhep-lat+1PPNP(2024)·121 citations
14. 14*

    Composite Topological Structures in SO(10)

    George Lazarides🇬🇷 · Qaisar Shafi🇺🇸 · Amit Tiwari🇺🇸

    We explore a variety of composite topological structures that arise from the spontaneous breaking of $SO(10)$ to $SU(3{)}_c\times U(1{)}_{em}$ via one of its maximal subgroups $SU(5)\times U(1{)}_{\chi }$, $SU(4{)}_c\times SU(2{)}_L\times SU(2{)}_R$, and $SU(5)\times U(1{)}_X$ (also known as flipped $SU(5)$). They include i) a network of $\mathbb{Z}$ strings which develop monopoles and turn into necklaces with the structure of ${\mathbb{Z}}_2$ strings, ii) dumbbells connecting two different types of monopoles, or monopoles and antimonpoles, iii) starfish-like configurations, iv) polypole configurations, and v) walls bounded by a necklace. We display these structures both before and after the electroweak breaking. The appearance of these composite structures in the early universe and their astrophysical implications including gravitational wave emission would depend on the symmetry breaking patterns and scales, and the nature of the associated phase transitions.

    hep-phhep-thJHEP(2023)·39 citations
15. 15*

    Inflation and Dark Matter in the $Z_5$ Model

    XinXin Qi🇨🇳 · Hao Sun🇨🇳

    We discuss the possibility of unifying dark matter physics and inflation in the $Z_5$ model of the two-component dark matter. Inflation driven by the two-component dark matter fields can be divided into two cases, singlet dark matter inflation and mixed dark matter inflation, where both two-component play the role of inflaton in the latter case. For dark matter, we focus on the mixed dark matter inflation case. We show a viable parameter space that satisfies the theoretical and dark matter relic density constraint in the case of successful inflation. It turns out that the dark matter density is dominated by the light component, which is consistent with the feature of the $Z_5$ model of the two-component dark matter.

    hep-phJCAP(2023)·8 citations
16. 16*

    Mass predictions of triply heavy hybrid baryons via QCD sum rules

    Yi-Cheng Zhao🇨🇳 · Chun-Meng Tang🇨🇳 · Liang Tang

    In this article, we study the mass spectrum of the low-lying triply heavy hybrid baryon, which consists of three valence heavy quarks in a color octet and one valence gluon, with spin-parity $J^P=(\frac{1}{2}{)}^{+}$ via QCD sum rules. This is the first study on the triply heavy hybrid baryons in the framework of QCD sum rules. After performing the QCD sum rule analysis, we find that the mass of $cccg$ hybrid baryon lies in $M_{cccg}=5.91-6.13$ GeV. As a byproduct, the mass of the triply bottom hybrid baryon state is extracted to be around $M_{bbbg}=14.62-14.82$ GeV. The contributions up to dimension eight at the leading order of ${\alpha }_s$ (LO) in the operator product expansion are taken into account in the calculation. The triply charmed hybrid baryon predicted in this work can decay into one doubly charmed baryon and one charmed meson. Especially, we propose to search for $cccg$ hybrid baryon with $J^P=(1/2{)}^{+}$ in the P-wave decay channels ${\Xi }_{cc}^{++}{D}^0$, ${\Xi }_{cc}^{+}{D}^{+}$, and ${\Xi }_{ccs}^{+}{D}_s^{+}$, which may be accessible in future BelleII, Super-B, PANDA, and LHCb experiments.

    hep-phhep-exEPJC(2023)·20 citations
17. 17*

    Tri-Resonant Leptogenesis

    P. Candia da Silva🇬🇧 · D. Karamitros🇬🇧 · T. McKelvey🇬🇧 · A. Pilaftsis🇬🇧

    We present a class of leptogenesis models where the light neutrinos acquire their observed mass through a symmetry-motivated construction. We consider an extension of the Standard Model, which includes three singlet neutrinos which have mass splittings comparable to their decay widths. We show that this tri-resonant structure leads to an appreciable increase in the observed CP asymmetry over that found previously in typical bi-resonant models. To analyse such tri-resonant scenarios, we solve a set of coupled Boltzmann equations, crucially preserving the variations in the relativistic degrees of freedom. We highlight the fact that small variations at high temperatures can have major implications for the evolution of the baryon asymmetry when the singlet neutrino mass scale is below $100$ GeV. We then illustrate how this variation can significantly affect the ability to find successful leptogenesis at these low masses. Finally, the parameter space for viable leptogenesis is delineated, and comparisons are made with current and future experiments.

    hep-phPoS(2023)·2 citations
18. 18*

    Efficient negative-weight elimination in large high-multiplicity Monte Carlo event samples

    Jeppe R. Andersen🇬🇧 · Andreas Maier🇩🇪 · Daniel Maître🇬🇧

    We demonstrate that cell resampling can eliminate the bulk of negative event weights in large event samples of high multiplicity processes without discernible loss of accuracy in the predicted observables. The application of cell resampling to much larger data sets and higher multiplicity processes such as vector boson production with up to five jets has been made possible by improvements in the method paired with drastic enhancement of the computational efficiency of the implementation.

    hep-phEPJC(2023)·17 citations
19. 19*

    Branching Fraction of the Decay $B^{+}\to {\pi }^{+}{\tau }^{+}{\tau }^{-}$ and Lepton Flavor Universality Test via the Ratio $R_{\pi }(\tau /\mu )$

    Ahmed Ali🇩🇪 · Alexander Ya. Parkhomenko🇷🇺 · Irina M. Parnova🇩🇪

    Among (semi)leptonic rare $B$-decays induced by the $b\to d$ flavor changing neutral current, the decay $B^{+}\to {\pi }^{+}{\mu }^{+}{\mu }^{-}$ is the only one observed so far experimentally. Related decays involving the $e^{+}{e}^{-}$ and ${\tau }^{+}{\tau }^{-}$ pairs are the targets for the ongoing experiments at the LHC, in particular LHCb, and Belle II. The muonic and electronic semileptonic decays have almost identical branching fractions in the Standard Model (SM). However, the tauonic decay $B^{+}\to {\pi }^{+}{\tau }^{+}{\tau }^{-}$ differs from the other two due to the higher reaction threshold which lies slightly below the $\psi (2S)$-resonance. We present calculations of the ditauon (${\tau }^{+}{\tau }^{-}$) invariant-mass distribution and the branching fraction $\mathrm{Br}(B^{+}\to {\pi }^{+}{\tau }^{+}{\tau }^{-})$ in the SM based on the Effective Electroweak Hamiltonian approach, taking into account also the so-called long-distance contributions. The largest theoretical uncertainty in the short-distance part of the decay rates is due to the $B\to \pi$ form factors, which we quantify using three popular parametrizations. The long-distance contribution can be minimized by a cut on the ditauon mass $m_{{\tau }^{+}{\tau }^{-}}>M_{\psi (2S)}$. Once available, the branching fractions in the tauonic and muonic (and electronic) modes provide stringent test of the lepton flavor universality in the $b\to d$ transitions. We illustrate this by calculating the ratio $R_{\pi }(\tau /\mu )\equiv \mathrm{Br}(B^{+}\to {\pi }^{+}{\tau }^{+}{\tau }^{-})/\mathrm{Br}(B^{+}\to {\pi }^{+}{\mu }^{+}{\mu }^{-})$ in the SM for the total and binned ratios of the branching fractions.

    hep-phhep-exhep-latPLB(2023)·4 citations
20. 20*

    Charmoniumlike tetraquarks in a chiral quark model

    Gang Yang🇨🇳 · Jialun Ping🇨🇳 · Jorge Segovia🇪🇸

    The lowest-lying charmonium-like tetraquarks $c\bar{c}q\bar{q}$ $(q=u,d)$ and $c\bar{c}s\bar{s}$, with spin-parity $J^P=0^{+}$, $1^{+}$ and $2^{+}$, and isospin $I=0$ and $1$, are systematically investigated within the theoretical framework of complex-scaling range for a chiral quark model that has already been successfully applied in former studies of various tetra- and penta-quark systems. A four-body $S$-wave configuration which includes meson-meson, diquark-antidiquark and K-type arrangements of quarks, along with all possible color wave functions, is comprehensively considered. Several narrow resonances are obtained in each tetraquark channel when a fully coupled-channel computation is performed. We tentatively assign theoretical states to experimentally reported charmonium-like signals such as $X(3872)$, $Z_c(3900)$, $X(3960)$, $X(4350)$, $X(4685)$ and $X(4700)$. They can be well identified as hadronic molecules; however, other exotic components which involve, for instance, hidden-color channels or diquark-antidiquark structures play a considerable role. Meanwhile, two resonances are obtained at $4.04$ GeV and $4.14$ GeV which may be compatible with experimental data in the energy interval $4.0-4.2$ GeV. Furthermore, the $X(3940)$ and $X(4630)$ may be identified as color compact tetraquark resonances. Finally, we also find few resonance states in the energy interval from $4.5$ GeV to $5.0$ GeV, which would be awaiting for discovery in future experiments.

    hep-phhep-exhep-latnucl-ex+1EPJC(2023)·14 citations
21. 21*

    Direct searches for general dark matter-electron interactions with graphene detectors: Part I. Electronic structure calculations

    Riccardo Catena🇸🇪 · Timon Emken🇸🇪 · Marek Matas🇨🇭 · Nicola A. Spaldin🇨🇭 · Einar Urdshals🇸🇪

    We develop a formalism to describe electron ejections from graphene-like targets by dark matter (DM) scattering for general forms of scalar and spin 1/2 DM-electron interactions and compare their applicability and accuracy within the density functional theory (DFT) and tight binding (TB) approaches. This formalism allows for accurate prediction of the daily modulation signal expected from DM in upcoming direct detection experiments employing graphene sheets as the target material. A key result is that the physics of the graphene sheet and that of the DM and the ejected electron factorise, allowing for the rate of ejections from all forms of DM to be obtained with a single graphene response function. We perform a comparison between the TB and DFT approaches to modeling the initial state electronic wavefunction within this framework, with DFT emerging as the more self-consistent and reliable choice due to the challenges in the embedding of an appropriate atomic contribution into the TB approach.

    hep-phastro-ph.COPRResearch(2023)·20 citations
22. 22*

    Direct searches for general dark matter-electron interactions with graphene detectors: Part II. Sensitivity studies

    Riccardo Catena🇸🇪 · Timon Emken🇸🇪 · Marek Matas🇨🇭 · Nicola A. Spaldin🇨🇭 · Einar Urdshals🇸🇪

    We use a formalism that describes electron ejections from graphene-like targets by dark matter (DM) scattering for general forms of scalar and spin 1/2 DM-electron interactions in combination with state-of-the-art density functional calculations to produce predictions and reach estimates for various possible carbon-based detector designs. Our results indicate the importance of a proper description of the target electronic structure. In addition, we find a strong dependence of the predicted observed signal for different DM candidate masses and interaction types on the detailed geometry and design of the detector. Combined with directional background vetoing, these dependencies will enable the identification of DM particle properties once a signal has been established.

    hep-phastro-ph.COPRResearch(2023)·22 citations
23. 23*

    SU(2) Gauge Theory in $2+1$ Dimensions on a Plaquette Chain Obeys the Eigenstate Thermalization Hypothesis

    Xiaojun Yao🇺🇸

    We test the eigenstate thermalization hypothesis (ETH) for 2+1 dimensional SU(2) lattice gauge theory. By considering the theory on a chain of plaquettes and truncating basis states for link variables at $j=1/2$, we can map it onto a quantum spin chain with local interactions and numerically exactly diagonalize the Hamiltonian for reasonably large lattice sizes. We find energy level repulsion in momentum sectors with no remaining discrete symmetry. We study two local observables made up of Wilson loops and calculate their matrix elements in the energy eigenbasis, which are shown consistent with the ETH.

    ↳ hep-latcond-mat.stat-mechhep-phnucl-th+1PRD(2023)·48 citations
24. 24*

    Improving robustness of jet tagging algorithms with adversarial training: exploring the loss surface

    Annika Stein🇩🇪

    In the field of high-energy physics, deep learning algorithms continue to gain in relevance and provide performance improvements over traditional methods, for example when identifying rare signals or finding complex patterns. From an analyst's perspective, obtaining highest possible performance is desirable, but recently, some attention has been shifted towards studying robustness of models to investigate how well these perform under slight distortions of input features. Especially for tasks that involve many (low-level) inputs, the application of deep neural networks brings new challenges. In the context of jet flavor tagging, adversarial attacks are used to probe a typical classifier's vulnerability and can be understood as a model for systematic uncertainties. A corresponding defense strategy, adversarial training, improves robustness, while maintaining high performance. Investigating the loss surface corresponding to the inputs and models in question reveals geometric interpretations of robustness, taking correlations into account.

    ↳ hep-excs.AIcs.LGhep-ph+1J.Phys.Conf.Ser.(2026)·2 citations
25. 25*

    Importance of higher orders in opacity in QGP tomography

    Stefan Stojku🇷🇸 · Bojana Ilic🇷🇸 · Igor Salom🇷🇸 · Magdalena Djordjevic🇷🇸

    We consider the problem of including a finite number of scattering centers in dynamical energy loss and classical DGLV formalism. Previously, either one or an infinite number of scattering centers were considered in energy loss calculations, while attempts to relax such approximations were largely inconclusive or incomplete. In reality, however, the number of scattering centers is generally estimated to be 4-5 at RHIC and the LHC, making the above approximations (a priori) inadequate and this theoretical problem significant for QGP tomography. We derived explicit analytical expressions for dynamical energy loss and DGLV up to the $4^{th}$ order in opacity, resulting in complex mathematical expressions that were, to our knowledge, obtained for the first time. These expressions were then implemented into an appropriately generalized DREENA framework to calculate the effects of higher orders in opacity on a wide range of high-$p_{\perp }$ light and heavy flavor predictions. Results of extensive numerical analysis, together with interpretations of nonintuitive results, are presented. We find that, for both RHIC and the LHC, higher-order effects on high-$p_{\perp }$ observables are small, and the approximation of a single scattering center is adequate for dynamical energy loss and DGLV formalisms.

    ↳ nucl-thhep-phPRC(2023)·4 citations
26. 26*

    Heavy-Flavour Jets in High-Energy Nuclear Collisions

    Sa Wang🇨🇳 · Wei Dai🇨🇳 · Enke Wang🇨🇳 · Xin-Nian Wang🇺🇸 · Ben-Wei Zhang

    Reconstructed jets initiated from heavy quarks provide a powerful tool to probe the properties of the quark-gluon plasma (QGP) and to explore the mass hierarchy of jet quenching. In this article, we review the recent theoretical progresses on heavy-flavour jets in high-energy nuclear collisions at the RHIC and LHC. We focus on the yields and substructures of charm and bottom quark jets with jet quenching effect, such as the nuclear modification factors, transverse momentum imbalance, angular correlation, radial profiles, fragmentation functions, the "dead-cone" effect, etc.

    ↳ nucl-thhep-phSymmetry(2023)·19 citations
27. 27*

    First Dark Matter Search with Nuclear Recoils from the XENONnT Experiment

    XENON Collaboration: E. Aprile🇺🇸 · K. Abe🇯🇵 · F. Agostini🇮🇹 · S. Ahmed Maouloud🇫🇷 · L. Althueser🇩🇪 · B. Andrieu🇫🇷 · E. Angelino🇮🇹 · J. R. Angevaare🇳🇱 · V. C. Antochi🇸🇪 · D. Antón Martin🇺🇸 · F. Arneodo🇦🇪 · L. Baudis🇨🇭 and 153 other authors

    We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of $5.9$ t. During the approximately 1.1 tonne-year exposure used for this search, the intrinsic ${}^{85}$Kr and ${}^{222}$Rn concentrations in the liquid target were reduced to unprecedentedly low levels, giving an electronic recoil background rate of $(15.8\pm 1.3)\mathrm{events}/(\mathrm{t}\cdot \mathrm{y}\cdot \mathrm{keV})$ in the region of interest. A blind analysis of nuclear recoil events with energies between $3.3$ keV and $60.5$ keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of $2.58\times 10^{-47}{\mathrm{cm}}^2$ for a WIMP mass of $28\mathrm{GeV}/c^2$ at $90\%$ confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

    ↳ hep-exastro-ph.COastro-ph.IMhep-ph+1PRL(2023)·744 citations
28. 28*

    New derivation of Time-Independent Perturbation Theory

    A. N. Kvinikhidze🇬🇪 · B. Blankleider🇦🇺

    We propose a new derivation of Time-Independent Perturbation Theory (PT) that has a fundamental advantage over the usual derivations presented in textbooks on Quantum Mechanics (QM): it is simpler and much shorter. As such, it can provide an easier and quicker way for students to learn PT, than afforded by current methods. In spite of that, our approach does not require the potentials to be energy independent or the inverse free Green function $G_0^{-1}(E)$ to be a linear function of energy $E$, as is the case in QM, and can be applied directly to various extensions of QM including Relativistic QM, the Bethe-Salpeter equation, and all kinds of quasipotential approaches in Quantum Field Theory.

    ↳ quant-phhep-phhep-thnucl-th0 citations
29. 29*

    Thermalization at the femtoscale seen in high-energy Pb+Pb collisions

    Rupam Samanta🇵🇱 · Somadutta Bhatta🇺🇸 · Jiangyong Jia🇺🇸 · Matthew Luzum🇧🇷 · Jean-Yves Ollitrault🇫🇷

    A collision between two atomic nuclei accelerated at a speed close to that of light creates a dense system of quarks and gluons. Interactions among them are so strong that they behave collectively like a droplet of fluid of ten-femtometer size, which expands into the vacuum and eventually fragments into thousands of particles. We report a new manifestation of thermalization in recent data from the Large Hadron Collider. Our analysis is based on results from the ATLAS Collaboration, which has measured the variance of the momentum per particle across Pb+Pb collision events with the same particle multiplicity. This variance decreases steeply over a narrow multiplicity range corresponding to central collisions. We provide a simple explanation of this newly-observed phenomenon: For a given multiplicity, the momentum per particle increases with increasing impact parameter. Since a larger impact parameter goes along with a smaller collision volume, this in turn implies that the momentum per particle increases as a function of density, which is a generic consequence of thermalization. Our analysis provides the first direct evidence of this phenomenon at the femtoscale.

    ↳ nucl-thhep-exhep-phnucl-exPRC(2024)·36 citations
30. 30*

    Constraint on Early Dark Energy from Isotropic Cosmic Birefringence

    Johannes R. Eskilt🇳🇴 · Laura Herold🇩🇪 · Eiichiro Komatsu🇩🇪 · Kai Murai🇯🇵 · Toshiya Namikawa🇯🇵 · Fumihiro Naokawa🇯🇵

    Polarization of the cosmic microwave background (CMB) is sensitive to new physics violating parity symmetry, such as the presence of a pseudoscalar "axionlike" field. Such a field may be responsible for early dark energy (EDE), which is active prior to recombination and provides a solution to the so-called Hubble tension. The EDE field coupled to photons in a parity-violating manner would rotate the plane of linear polarization of the CMB and produce a cross-correlation power spectrum of $E$- and $B$-mode polarization fields with opposite parities. In this paper, we fit the $EB$ power spectrum predicted by the photon-axion coupling of the EDE model with a potential $V(\varphi )\propto [1-\cos (\varphi /f){]}^3$ to polarization data from Planck. We find that the unique shape of the predicted $EB$ power spectrum is not favored by the data and obtain a first constraint on the photon-axion coupling constant, $g=(0.04\pm 0.16)M_{\text{Pl}}^{-1}$ (68% CL), for the EDE model that best fits the CMB and galaxy clustering data. This constraint is independent of the miscalibration of polarization angles of the instrument or the polarized Galactic foreground emission. Our limit on $g$ may have important implications for embedding EDE in fundamental physics, such as string theory.

    ↳ astro-ph.COhep-phhep-thPRL(2023)·71 citations
31. 31*

    Anticipating the XRISM search for the decay of resonantly produced sterile neutrino dark matter

    Mark R. Lovell (1) ((1) Durham University)🇮🇸

    The sterile neutrino ($N_1$) features in multiple extensions of the standard model and is a compelling dark matter candidate, especially as the decay of $N_1$ with mass $m_{\mathrm{s}}=7.1\mathrm{keV}$ is a possible source for the unexplained $3.55\mathrm{keV}$ X-ray line reported in galaxy clusters. This particle will be accessible to the XRISM X-ray mission over the next 12 months. We revisit the physics behind $N_1$ and the uncertainty in its parameters. We compare predictions for the $m_s=7.1\mathrm{keV}$ $N_1$ mixing angle, ${\sin }^2(2\theta )$, and half-mode mass, $M_{\mathrm{hm}}$, as described in the $\nu$MSM standard model extension to existing X-ray observations and structure formation constraints. The strongest available constraints rule out $N_1$ as a dark matter candidate, and a more optimistic reading of the data prefers ${\sin }^2(2\theta )=5\times 10^{-11}$ and $M_{\mathrm{hm}}=3.5\times 10^8{M}_{\odot }$. We highlight that the most promising upcoming opportunity for a detection is to find a line of velocity dispersion $\sim 500{\mathrm{kms}}^{-1}$ in the Virgo cluster with XRISM, and then draw up a list of future objects of study to determine: (i) whether the line is from dark matter generally, and (ii) if from dark matter, whether that candidate is indeed $N_1$.

    ↳ astro-ph.COhep-phMNRAS(2023)·13 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.