Tue·Jul 18, 2023Tuesday·July 18, 2023

1. 01*

   Photon and dilepton emission anisotropy for a magnetized quark-gluon plasma

   Xinyang Wang🇨🇳 · Igor A. Shovkovy🇺🇸

   We study the higher-order anisotropy coefficients $v_4$ and $v_6$ in the photon and dilepton emission from a hot magnetized quark-gluon plasma. Together with the earlier predictions for $v_2$, these results show a distinctive pattern of the anisotropy coefficients in several kinematic regimes. In the case of photon emission, nonzero coefficients $v_n$ (with even $n$) have opposite signs at small and large values of the transverse momentum (i.e., $k_T\lesssim \sqrt{|eB|}$ and $k_T\gtrsim \sqrt{|eB|}$, respectively). Additionally, the $v_n$ signs alternate with increasing $n$, and their approximate values decrease as $1/n^2$ in magnitude. The anisotropy of dilepton emission is well pronounced only at large transverse momenta and small invariant masses (i.e., when $k_T\gtrsim \sqrt{|eB|}$ and $M\lesssim \sqrt{|eB|}$). The corresponding $v_4$ and $v_6$ coefficients are of the same magnitude and show a similar alternating sign pattern with increasing $n$ as in the photon emission.

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

   Soft resummation in processes with heavy quark: bridging the gap from 4-flavor to 5-flavor scheme

   Andrea Ghira🇮🇹

   In this work we present a new approach to threshold resummation in processes with heavy quarks. In particular we will focus on the differential decay rate of a color-singlet particle into a $b\bar{b}$ pair and we will show how to resum in a consistent way both the logarithms of the mass and the logarithms of the heavy flavor energy fraction. Within this framework, we match the two different approaches existing in literature to threshold resummation, the main difference of which is the way in which the mass is treated (5-flavor scheme vs 4-flavor scheme).

   hep-ph0 citations
3. 03*

   Soft photon corrections in $B\to K^{(\ast )}{\ell }^{+}{\ell }^{-}$ and ${\Lambda }_b\to {\Lambda }^{(\ast )}{\ell }^{+}{\ell }^{-}$ decays

   Debajyoti Choudhury🇮🇳 · Diganta Das🇮🇳 · Jaydeb Das🇮🇳

   We calculate QED corrections to the semileptonic decays $H_1\to H_2{\ell }^{+}{\ell }^{-}$ where $\ell =e,\mu$ and $H_{1,2}$ are hadrons. The soft and/or collinear divergences are regulated in a gauge-invariant manner and demonstrably cancel, leaving behind a finite residue that depends on the (infrared) momentum cutoff below which a photon is considered to be indistinguishable. On resuming, the said sensitivity reduces drastically, $i$.$e$., for the NLL result as compared to the NLO one. The overall correction is negative and its magnitude is larger for a lighter lepton. For $B\to K^{(\ast )}$ decays, the corrections improve the agreement for the differential distributions, while the behavior is more complicated for ${\Lambda }_b\to {\Lambda }^{(\ast )}$ decays. Rather intriguingly, the corrections serve to regenerate the tension for the lepton flavor universality observables $R_K$ and $R_{K^{\ast }}$.

   hep-ph3 citations
4. 04*

   Non-factorisable effects in the decays ${\bar{B}}_s^0\to D_s^{+}{\pi }^{-}$ and ${\bar{B}}^0\to D^{+}{K}^{-}$ from LCSR

   Maria Laura Piscopo🇩🇪 · Aleksey Rusov🇩🇪

   In light of the current discrepancies between the recent predictions based on QCD factorisation (QCDF) and the experimental data for several non-leptonic colour-allowed two-body $B$-meson decays, we obtain new determinations of the non-factorisable soft-gluon contribution to the decays ${\bar{B}}_s^0\to D_s^{+}{\pi }^{-}$ and ${\bar{B}}^0\to D^{+}{K}^{-}$, using the framework of light-cone sum rule (LCSR), with a suitable three-point correlation function and $B$-meson light-cone distribution amplitudes. In particular, we discuss the problem associated with a double light-cone (LC) expansion of the correlator, and motivate future determinations of the three-particle $B$-meson matrix element with the gluon and the spectator quark aligned along different light-cone directions. Performing a LC-local operator product expansion of the correlation function, we find, for both modes considered, the non-factorisable part of the amplitude to be sizeable and positive, however, with very large systematic uncertainties. Furthermore, we also determine for the first time, using LCSR, the factorisable amplitudes at LO-QCD, and thus the corresponding branching fractions. Our predictions are in agreement with the experimental data and consistent with the results based on QCDF, although again within very large uncertainties. In this respect, we provide a rich outlook for future improvements and investigations.

   hep-phhep-exJHEP(2023)·37 citations
5. 05*

   Catastrogenesis with unstable ALPs as the origin of the NANOGrav 15 yr gravitational wave signal

   Graciela B. Gelmini🇺🇸 · Jonah Hyman🇺🇸

   In post-inflation axion-like particle (ALP) models, a stable domain wall network forms if the model's potential has multiple minima. This system must annihilate before dominating the Universe's energy density, producing ALPs and gravitational waves (a process we dub "catastrogenesis," or "creation via annihilation"). We examine the possibility that the gravitational wave background recently reported by NANOGrav is due to catastrogenesis. For the case of ALP decay into two photons, we identify the region of ALP mass and coupling, just outside current limits, compatible with the NANOGrav signal.

   hep-phPLB(2024)·26 citations
6. 06*

   Bouncing pNGB Dark Matter via a Fermion Dark Matter

   Bastián Díaz Sáez🇨🇱 · Patricio Escalona Contreras🇨🇱

   In addition to the Standard Model, the introduction of a singlet complex scalar field that acquires vacuum expectation value may give rise to a cosmologically stable pseudo-Nambu-Goldstone boson (pNGB), a suitable dark matter (DM) candidate. This work extends this scenario by including a second cosmologically stable particle: a fermion singlet. The pNGB and the new fermion can be regarded as DM candidates simultaneously, both interacting with the Standard Model through Higgs portals via two non-degenerate Higgs bosons. We explore the thermal freeze-out of this scenario, with particular emphasis on the increasing yield of the pNGB before it completely decouples (recently called Bouncing DM). We test the model under collider bounds, relic abundance, and direct detection, and we explore some indirect detection observables today.

   hep-phastro-ph.COJCAP(2024)·13 citations
7. 07*

   Towards a New nCTEQ global nPDF release

   P. Risse🇩🇪 · N. Derakhshanian🇵🇱 · P. Duwentäster🇫🇮 · T. Ježo🇩🇪 · C. Keppel🇺🇸 · M. Klasen🇩🇪 · K. Kovařík🇩🇪 · A.Kusina🇵🇱 · C. Léger🇫🇷 · J.G.Morfín🇺🇸 · F.I. Olness🇺🇸 · R. Ruiz🇵🇱 · I. Schienbein🇫🇷 · J.Y. Yu🇫🇷

   We discuss the foundation for a new global nCTEQ nuclear PDF analysis, combining a number of our previous analyses into one consistent framework with updates to the underlying theoretical treatment as well as the addition of new available data. In particular, the new global release will be the first nCTEQ release containing neutrino DIS scattering data in a consistent manner together with JLab high-x DIS data and new LHC p-Pb data. These additions will improve the data-driven description of nuclear PDFs in new regions, especially the strange quark and the gluon PDF at low-x.

   hep-ph4 citations
8. 08*

   Fully-strange tetraquark states with the exotic quantum numbers $J^{PC}=0^{+-}$ and $2^{+-}$

   Hong-Zhou Xi🇨🇳 · Yi-Wei Jiang🇨🇳 · Hua-Xing Chen🇨🇳 · Atsushi Hosaka🇯🇵 · Niu Su🇨🇳

   We study the fully-strange tetraquark states with the exotic quantum numbers $J^{PC}=0^{+-}$ and $2^{+-}$. We construct their corresponding diquark-antidiquark interpolating currents, and apply the QCD sum rule method to calculate both their diagonal and off-diagonal correlation functions. The obtained results are used to construct some mixing currents that are nearly non-correlated, from which we extract the masses of the lowest-lying states to be $M_{0^{+-}}=2.45_{-0.44}^{+0.33}$ GeV and $M_{2^{+-}}=3.07_{-0.33}^{+0.25}$ GeV. We apply the Fierz rearrangement to transform the diquark-antidiquark currents to be the combinations of meson-meson currents, and the obtained Fierz identities indicate that these two states may be searched for in the $P$-wave $\varphi (1020)f_0(1710)/\varphi (1020)f_2^{\prime }(1525)(\to \varphi K\bar{K}/\varphi \pi \pi )$ channels.

   hep-phPRD(2023)·12 citations
9. 09*

   Probing Parton distribution functions at large x via Drell-Yan Forward-Backward Asymmetry

   Yao Fu🇨🇳 · Raymond Brock🇺🇸 · Daniel Hayden🇺🇸 · Chien-Peng Yuan🇺🇸

   The forward-backward asymmetry of the Drell-Yan process in dilepton decays at high invariant masses can be used to probe the parton distribution functions at large x. The behavior of three modern PDF sets (CT18NNLO, MSHT20, and NNPDF4.0) are compared, and updated under various scenarios via ePump using proton-proton collision pseudo-data generated at sqrt(s) = 13 TeV with 3000 fb^{-1} of integrated luminosity.

   hep-phhep-exPRD(2024)·10 citations
10. 10*

    Studying QGP transport properties in a concurrent minijet+hydro framework

    Charles Gale🇨🇦 · Sangyong Jeon🇨🇦 · Daniel Pablos🇮🇹 · Mayank Singh🇺🇸

    Minijets are ubiquitous in heavy-ion collision experiments. However, they are often excluded from the hydrodynamic simulations of QGP as they do not thermalize at short time scales and are not treated as part of the collective medium. Using a concurrent jet+hydro framework, we show that the minijets could account for a significant portion of particle multiplicity. Therefore, the energy deposition from minijet-medium interactions can substantially modify the QGP transport properties inferred from model-to-data comparisons.

    hep-phnucl-thPoS(2024)·0 citations
11. 11*

    Minicharged Particles at Accelerators: Progress and Prospects

    Marc de Montigny🇨🇦 · Pierre-Philippe A. Ouimet🇨🇦 · James Pinfold🇨🇦 · Ameir Shaa🇨🇦 · Michael Staelens🇪🇸

    Minicharged particles (mCPs), hypothetical free particles with effective electric charges much smaller than the elementary charge, $e$, offer a valuable probe of dark sectors and fundamental physics through several clear experimental signatures. Various models of physics beyond the Standard Model predict such particles, the existence of which could help elucidate the ongoing mysteries regarding electric charge quantization and the nature of dark matter. Moreover, a hypothetical scenario involving a small minicharged subcomponent of dark matter has recently been demonstrated as a viable explanation of the anomaly in the 21 cm hydrogen absorption signal reported by the EDGES collaboration. Although several decades of indirect observations and direct experimental searches for mCPs at particle accelerators have led to severe constraints, a substantial window of the mCP mass$–$mixing parameter space remains unexplored at the energy frontier accessible to current state-of-the-art accelerators, such as the Large Hadron Collider (LHC). Consequently, mCPs have remained topical over the years, and new experimental searches at accelerators have been gaining interest. In this article, we review the theoretical frameworks in which mCPs emerge and their phenomenological implications, the current direct and indirect constraints on mCPs, and the present state of the ongoing and upcoming searches for mCPs at particle accelerators.

    hep-phhep-ex16 citations
12. 12*

    Comparative multi-probe study of jet energy-loss in QGP

    Rouzbeh Modarresi Yazdi🇨🇦 · Shuzhe Shi🇨🇳 · Charles Gale🇨🇦 · Sangyong Jeon🇨🇦

    Jet-energy loss is an important sign of the creation of Quark-Gluon Plasma in heavy-ion collisions. High transverse momentum ($p_T$) partons are produced at the moment of initial hard scattering and are modified as a result of their propagation through the created medium. We study two models of low-virtuality radiative energy loss: CUJET and MARTINI. This is done using the JETSCAPE framework, which allows for an objective comparison. CUJET is integrated into the JETSCAPE workflow, and full jet simulations, including substructure observables, are computed for the first time using leading-order DGLV rates. Strongly-interacting probes (charged hadrons, jets, jet fragmentation functions and jet shape ratio) are considered along jet-medium photons for the first time in a dynamic QGP. We find that these photons make a significant contribution in the phenomenologically interesting intermediate $p_T$ domain of $4$-$12$ GeV.

    hep-phnucl-thPoS(2024)·1 citation
13. 13*

    The global $B-L$ symmetry in the flavor-unified $\mathrm{SU}(N)$ theories

    Ning Chen🇨🇳 · Ying-nan Mao🇨🇳 · Zhaolong Teng🇨🇳

    We study the origin of the global $B-L$ symmetry in a class of flavor-unified theories with gauge groups of $\mathrm{SU}(N\ge 6)$. In particular, we focus on the $\mathrm{SU}(8)$ theory which can minimally embed three-generational SM fermions non-trivially. A reformulation of the third law for the flavor sector proposed by Georgi is useful to manifest the underlying global symmetries. The 't Hooft anomaly matching and the generalized neutrality conditions for Higgs fields play the key roles in defining the $B-L$ symmetry. Based on the global $B-L$ symmetry, we count the Higgs fields that can develop the VEVs and the massless sterile neutrinos in the $\mathrm{SU}(8)$ theory. We also prove that a global $B-L$ symmetry can always be defined in any $\mathrm{SU}(N\ge 6)$ theory when it is spontaneously broken to the SM gauge symmetry.

    hep-phhep-thJHEP(2024)·7 citations
14. 14*

    Heavy quark $\kappa$ and jet $\hat{q}$ transport coefficients in the Glasma early stage of heavy-ion collisions

    Dana Avramescu🇫🇮 · Virgil Băran🇷🇴 · Vincenzo Greco🇮🇹 · Andreas Ipp🇦🇹 · David. I. Müller🇦🇹 · Marco Ruggieri🇮🇹

    We study the impact of the Glasma fields, used to describe the very early stage of heavy-ion collisions, on the transport of hard probes, namely heavy quarks and jets. We perform numerical simulations of the strong classical fields using techniques from real-time lattice gauge theory. The resulting fields are used as background for the classical transport of ensembles of particles, described by Wong's equations. For this purpose, we develop a numerical solver for the transport of the probes, based on colored particle-in-cell methods. We focus on the dynamics of heavy quarks and jets in the classical colored fields. To quantify the effect of the Glasma, we extract the momentum broadening of hard probes and evaluate the anisotropy transfer from the Glasma to the probes. Lastly, we evaluate the heavy quark $\kappa$ and jet $\hat{q}$ transport coefficients in the Glasma, which turn out to be large and exhibit a peak, irrespective of the particle initialization.

    hep-phhep-latnucl-thPoS(2024)·4 citations
15. 15*

    Probing the $Zb\bar{b}$ coupling at the $Z$-pole of future lepton colliders

    Bin Yan🇨🇳 · C.-P. Yuan🇺🇸 · Shu-Run Yuan🇨🇳

    The determination of the $Zb\bar{b}$ coupling in experiments has been a long-standing challenge, as the limited precision of off $Z$-pole measurements at the LEP has resulted in two degenerate solutions remained to be resolved. In this paper, we propose a novel method to probe the $Zb\bar{b}$ coupling by measuring the forward-backward asymmetry of the bottom quark, $A_{\text{FB}}^b$, in the $b\bar{b}$ system of the $e^{+}{e}^{-}\to b\bar{b}\gamma$ and/or $e^{+}{e}^{-}\to b\bar{b}g$ processes at the $Z$-pole of future lepton colliders. The additional hard photon or light jet radiation can mimic the energy scanning of the $e^{+}{e}^{-}\to b\bar{b}$ process, and the $A_{\mathrm{FB}}^b$ distribution from the $\gamma$-$Z$ interference process is linearly sensitive to the $Zb\bar{b}$ coupling. By combining the expected measurements of $R_b^0$ and $A_{\text{FB}}^{0,b}$ at the $Z$-pole at the CEPC, the $A_{\text{FB}}^b$ distributions can break the degeneracy observed at the LEP, leading to a unique determination of the $Zb\bar{b}$ coupling through $Z$-pole running alone.

    hep-phhep-exPRD(2023)·4 citations
16. 16*

    NANOGrav Signal and PBH from the Modified Higgs Inflation

    Kingman Cheung🇹🇼 · C.J. Ouseph🇹🇼 · Po-Yan Tseng🇹🇼

    This study investigates the classical Higgs inflation model with a modified Higgs potential featuring a dip. We examine the implications of this modification on the generation of curvature perturbations, stochastic gravitational wave production, and the potential formation of primordial black holes (PBHs). Unlike the classical model, the modified potential allows for enhanced power spectra and the existence of PBHs within a wide mass range $1.5\times 10^{20}$ g -- $9.72\times 10^{32}$ g. We identify parameter space regions that align with inflationary constraints and have the potential to contribute significantly to the observed dark matter content. Additionally, the study explores the consistency of the obtained parameter space with cosmological constraints and discusses the implications for explaining the observed excess in gravitational wave signals, particularly in the NANOGrav experiment. Overall, this investigation highlights the relevance of the modified Higgs potential in the classical Higgs inflation model, shedding light on the formation of PBHs, the nature of dark matter, and the connection to gravitational wave observations.

    hep-phastro-ph.COhep-thEPJC(2024)·39 citations
17. 17*

    Top squarks from the landscape at high luminosity LHC

    Howard Baer🇺🇸 · Vernon Barger🇺🇸 · Juhi Dutta🇺🇸 · Dibyashree Sengupta🇮🇹 · Kairui Zhang🇺🇸

    Supersymmetric models with low electroweak finetuning are expected to be more prevalent on the string landscape than finetuned models. We assume a fertile patch of landscape vacua containing the minimal supersymmetric standard model (MSSM) as low energy/weak scale effective field theory (LE-EFT). Then, a statistical pull by the landscape to large soft terms is balanced by the requirement of a derived value of the weak scale which is not too far from its measured value in our universe. Such models are characterized by light higgsinos in the few hundred GeV range whilst top squarks are in the 1-2.5 TeV range with large trilinear soft terms which helps to push m_h~ 125 GeV. Other sparticles are generally beyond current LHC reach and the BR(b -> s\gamma ) branching fraction is nearly equal to its SM value. The light top-squarks decay comparably via \tst_1 -> b\tchi_1^+ and \tst_1 -> t\tchi_{1,2}^0 yielding mixed final states of b\bar{b}+MET, t\bar{b}/\ \bar{t}b + MET and t\bar{t}+ MET. We evaluate prospects for top squark discovery at high-luminosity (HL) LHC for the well-motivated case of natural SUSY from the landscape. We find for HL-LHC a 5\sigma reach out to m_{\tst_1}~ 1.7 TeV and a 95\% CL exclusion reach to m_{\tst_1} ~ 2 TeV. These reaches cover {\it most} (but not all) of the allowed stringy natural parameter space!

    hep-phPRD(2023)·19 citations
18. 18*

    Entanglement Suppression, Enhanced Symmetry and a Standard-Model-like Higgs Boson

    Marcela Carena🇺🇸 · Ian Low🇺🇸 · Carlos E. M. Wagner🇺🇸 · Ming-Lei Xiao🇺🇸

    We study information-theoretic properties of scalar models containing two Higgs doublets ${\Phi }_a$, where $a=1,2$ is the flavor quantum number. Considering the 2-to-2 scattering ${\Phi }_a{\Phi }_b\to {\Phi }_c{\Phi }_d$ as a two-qubit system in the flavor subspace and the S-matrix as a quantum logic gate, we analyze the entanglement power of the S-matrix at the tree-level, in the limit the gauge coupling is turned off. Demanding the suppression of flavor entanglement during the scattering, the perturbative S-matrix in the broken phase can only be in the equivalent class of the Identity gate and the scalar potential exhibits a maximally enhanced $SO(8)$ symmetry acting on the 8 real components of the two doublets. The $SO(8)$ symmetry leads to the alignment limit naturally, giving rise to a Standard-Model-like Higgs boson as a consequence of entanglement suppression.

    hep-phhep-thquant-phPRD(2024)·61 citations
19. 19*

    Effects of multi-scale jet-medium interactions on jet substructures

    JETSCAPE Collaboration: Y. Tachibana · A. Angerami · R. Arora · S. A. Bass · S. Cao · Y. Chen · T. Dai · L. Du · R. Ehlers · H. Elfner · W. Fan · R. J. Fries and 47 other authors

    We utilize event-by-event Monte Carlo simulations within the JETSCAPE framework to examine scale-dependent jet-medium interactions in heavy-ion collisions. The reduction in jet-medium interaction during the early high-virtuality stage, where the medium is resolved at a short distance scale, is emphasized as a key element in explaining multiple jet observables, particularly substructures, simultaneously. By employing the MATTER+LBT setup, which incorporates this explicit reduction of medium effects at high virtuality, we investigate jet substructure observables, such as Soft Drop groomed observables. When contrasted with existing data, our findings spotlight the significant influence of the reduction at the early high-virtuality stages. Furthermore, we study the substructure of gamma-tagged jets, providing predictive insights for future experimental analyses. This broadens our understanding of the various contributing factors involved in modifying jet substructures.

    hep-phhep-exnucl-exnucl-thPoS(2024)·0 citations
20. 20*

    Fast evaluation of heavy-quark contributions to DIS in APFEL++

    P. Risse🇩🇪 · V. Bertone🇫🇷 · T. Ježo🇩🇪 · M. Klasen🇩🇪 · K. Kovařík🇩🇪 · F.I. Olness🇺🇸 · I. Schienbein🇫🇷

    Mass-dependent quark contributions are of great importance to DIS processes. The simplified-ACOT-scheme includes these effects over a wide range of momentum transfers up to next-to-leading order in QCD. In recent years an improvement in the case of neutral current DIS has been achieved by using zero-mass contributions up to next-to-next-to-leading order (NNLO) with massive phase-space constraints. In this work, we extend this approach to the case of charged current DIS and provide an implementation in the open-source code APFEL++. The increased precision will be valuable for ongoing and future neutrino programs, the Electron-Ion-Collider and the studies of partonic substructure of hadrons and nuclei. A highly efficient implementation using gridding techniques extends the applicability of the code to the determination of parton distribution functions (PDFs).

    hep-ph3 citations
21. 21*

    $B_{(s)}\to D_{(s)}^{\ast \ast }$ form factors in HQEFT and model independent analysis of relevant semileptonic decays with NP effects

    Ya-Bing Zuo🇨🇳 · Hong-Yao Jin🇨🇳 · Jing-Ying Tian🇨🇳 · Jia Yi🇨🇳 · Han-Yu Gong🇨🇳 · Ting-Ting Pan🇨🇳

    The form factors of $B_{(s)}$ decays into P-wave excited charmed mesons (including $D_0^{\ast }(2300)$, $D_1(2430)$, $D_1(2420)$, $D_2^{\ast }(2460)$ and their strange counterparts, denoted generically as $D_{(s)}^{\ast \ast }$) are systematically calculated via the QCD sum rules in the framework of heavy quark effective field theory (HQEFT). We consider contributions up to the next leading order of heavy quark expansion and give all the relevant form factors, including the scalar and tensor ones only relevant for possible new physics effects. The expressions for the form factors in terms of several universal wave functions are derived via heavy quark expansion. These universal functions can be evaluated through QCD sum rules. Then, the numerical results of the form factors are presented. With the form factors given here, a model independent analysis of relevant semileptonic decays $B_{(s)}\to D_{(s)}^{\ast \ast }l{\bar{\nu }}_l$ is performed, including the contributions from possible new physics effects. Our predictions for the differential decay widths, branching fractions and ratios of branching fractions $R(D_{(s)}^{\ast \ast })$ may be tested in more precise experiments in the future.

    hep-phCPC(2023)·7 citations
22. 22*

    Higher molecular $P_{\psi s}^{\Lambda /\Sigma }$ pentaquarks arising from the ${\Xi }_c^{(\prime ,\ast )}{\bar{D}}_1/{\Xi }_c^{(\prime ,\ast )}{\bar{D}}_2^{\ast }$ interactions

    Fu-Lai Wang🇨🇳 · Xiang Liu🇨🇳

    The discoveries of the $P_{\psi s}^{\Lambda }(4459)$ and $P_{\psi s}^{\Lambda }(4338)$ as the potential ${\Xi }_c{\bar{D}}^{(\ast )}$ molecules have sparked our curiosity in exploring a novel class of molecular $P_{\psi s}^{\Lambda /\Sigma }$ pentaquarks. In this study, we carry out an investigation into the higher molecular pentaquarks, specifically focusing on the $P_{\psi s}^{\Lambda /\Sigma }$ states arising from the ${\Xi }_c^{(\prime ,\ast )}{\bar{D}}_1/{\Xi }_c^{(\prime ,\ast )}{\bar{D}}_2^{\ast }$ interactions. Our approach employs the one-boson-exchange model, incorporating both the $S$-$D$ wave mixing effect and the coupled channel effect. Our numerical results suggest that the ${\Xi }_c{\bar{D}}_1$ states with $I(J^P)=0(1/2^{+},3/2^{+})$, the ${\Xi }_c{\bar{D}}_2^{\ast }$ states with $I(J^P)=0(3/2^{+},5/2^{+})$, the ${\Xi }_c^{\prime }{\bar{D}}_1$ states with $I(J^P)=0(1/2^{+},3/2^{+})$, the ${\Xi }_c^{\prime }{\bar{D}}_2^{\ast }$ states with $I(J^P)=0(3/2^{+},5/2^{+})$, the ${\Xi }_c^{\ast }{\bar{D}}_1$ states with $I(J^P)=0(1/2^{+},3/2^{+},5/2^{+})$, and the ${\Xi }_c^{\ast }{\bar{D}}_2^{\ast }$ states with $I(J^P)=0(1/2^{+},3/2^{+},5/2^{+},7/2^{+})$ can be recommended as the most promising molecular $P_{\psi s}^{\Lambda }$ pentaquark candidates, and there may exist the potential molecular $P_{\psi s}^{\Sigma }$ pentaquark candidates for several isovector ${\Xi }_c^{(\prime ,\ast )}{\bar{D}}_1/{\Xi }_c^{(\prime ,\ast )}{\bar{D}}_2^{\ast }$ states. With the higher statistical data accumulation at the LHCb's Run II and Run III status, there is the possibility that our predicted $P_{\psi s}^{\Lambda /\Sigma }$ states can be detected through the weak decay of the ${\Xi }_b$ baryon, especially in hunting for the predicted $P_{\psi s}^{\Lambda }$ states.

    hep-phPRD(2023)·25 citations
23. 23*

    System size dependence of pre-equilibrium and applicability of hydrodynamics in heavy-ion collisions

    Victor E. Ambruş🇷🇴 · Sören Schlichting🇩🇪 · Clemens Werthmann🇩🇪

    We simulate the space-time dynamics of high-energy collisions based on a microscopic kinetic description, in order to determine the range of applicability of an effective description in relativistic viscous hydrodynamics. We find that hydrodynamics provides a quantitatively accurate description of collective flow when the average inverse Reynolds number ${\mathrm{Re}}^{-1}$ is sufficiently small and the early pre-equilibrium stage is properly accounted for. By determining the breakdown of hydrodynamics as a function of system size and energy, we find that it is quantitatively accurate in central lead-lead collisions at LHC energies, but should not be used in typical proton-lead or proton-proton collisions, where the development of collective flow can not accurately be described within hydrodynamics.

    hep-phnucl-thPoS(2024)·4 citations
24. 24*

    Repercussions of the Peccei-Quinn axion on QCD

    Gerrit Schierholz🇩🇪

    The axion, originally postulated by Peccei and Quinn to solve the strong CP problem, has become of great interest in particle and astroparticle phenomenology. Yet it has a problem. It is widely assumed that the axion leaves the nonperturbative features of QCD unscathed. This is, however, not the case. On the contrary, the axion extension is found to be in conflict with seminal results on the low-energy properties of QCD. The key is that the anomalous coupling of the axion to the gauge bosons can be integrated out, leaving behind a path integral over topologically trivial gauge potentials.

    hep-phhep-lathep-thnucl-thMod.Phys.Lett.A(2025)·3 citations
25. 25*

    Search for axion resonances in vacuum birefringence with three-beam collisions

    Stefan Evans🇩🇪 · Ralf Schützhold🇩🇪

    We consider birefringent (i.e., polarization changing) scattering of x-ray photons at the superposition of two optical laser beams of ultra-high intensity and study the resonant contributions of axions or axion-like particles, which could also be short-lived. Applying the specifications of the Helmholtz International Beamline for Extreme Fields (HIBEF), we find that this set-up can be more sensitive than previous light-by-light scattering (birefringence) or light-shining-through-wall experiments in a certain domain of parameter space. By changing the pump and probe laser orientations and frequencies, one can even scan different axion masses.

    hep-phquant-phPRD(2024)·6 citations
26. 26*

    Predictions of the hybrid mesons with exotic quantum numbers $J^{PC}=2^{+-}$

    Qi-Nan Wang🇨🇳 · Ding-Kun Lian🇨🇳 · Wei Chen🇨🇳

    We study the non-strange and strangeonium light hybrid mesons with $J^{PC}=2^{+-}$ by using the method of QCD sum rules. The local hybrid interpolating currents with three Lorentz indices are constructed to couple to such exotic quantum numbers. We calculate the correlation functions up to dimension eight condensates at the leading order of ${\alpha }_s$. In our results, the masses of the non-strange $b_2$ and $h_2$ hybrids are about $2.65\mathrm{GeV}$, while that of the strangeonium $h_2^{\prime }$ hybrid is about $2.72\mathrm{GeV}$. Such exotic $2^{+-}$ hybrids can be generated through both the two-gluon and three-gluon emission processes in the radiative decays of ${\chi }_{cJ}$. Moreover, these hybrid mesons may be detectable due to their peculiar decay behaviors and small decay widths. Using the high-statistics data samples of $\psi (3686)$ in BESIII and BelleII, it is possible to hunt for such hybrid states through the partial wave analyses in the $b_2\to \omega /a_1/h_1/a_2\pi \to 4\pi$, $h_2\to \rho \pi \to 3\pi$ and $h_2\to b_1\pi \to 5\pi$ processes.

    hep-phhep-exPRD(2023)·14 citations
27. 27*

    Standard Model Higgs inflation supplemented by minimal dark matter

    Shinsuke Kawai🇰🇷 · Nobuchika Okada🇺🇸 · Qaisar Shafi🇺🇸

    Renormalisation group analysis with the present measurements of the top quark mass $m_t=172.69\pm 0.30$ GeV indicates that the Standard Model (SM) Higgs potential becomes unstable at energy scales $\sim 10^{10}$ GeV. This may be interpreted as hinting at new particles at high energy. The minimal extension of the SM that can avoid this instability while leaving the SM Higgs as the sole scalar particle of the theory is obtained by adding suitable fermions to the SM. These fermions are good dark matter candidates and the model is known as the minimal dark matter model. We revisit the inflationary scenario based on the minimal dark matter model, taking into account updated parameter constraints and recent understanding of reheating dynamics. We explore the model with different values of the right-handed neutrino mass and find that the cosmological prediction is insensitive to such details. We obtained a spectral index of the cosmic microwave background $n_s=0.9672$ and a tensor-to-scalar ratio $r=0.0031$ as a robust prediction of this scenario.

    hep-phastro-ph.COhep-thPRD(2024)·4 citations
28. 28*

    Analysis of double-$J/\psi$ production in $Z$ decay at next-to-leading-order QCD accuracy

    Cong Li🇨🇳 · Zhan Sun🇨🇳 · Gui-Yuan Zhang🇨🇳

    In this article, we study in detail the double-$J/\psi$ yield through $Z$ decay at the next-to-leading-order (NLO) QCD accuracy within the nonrelativistic QCD factorization. At the tree level, the pure QCD diagrams predict a branching ratio of ${\mathcal{B}}_{Z\to J/\psi +J/\psi }\sim 10^{-12}$; however, the inclusion of the QED diagrams would augment this prediction by approximately 2-3 orders of magnitude. After incorporating the QCD corrections, the QCD results exhibit a considerable increase, whereas the QED results undergo a substantial reduction. Combining the QCD and QED contributions at NLO in ${\alpha }_s$, it is observed that the prediction of ${\mathcal{B}}_{Z\to J/\psi +J/\psi }=(1.110_{-0.241-0.001}^{+0.334+0.054})\times 10^{-10}$, which displays a fairly steady dependence on the renormalization scale, is significantly lower than the upper limits released by CMS.

    hep-phJHEP(2023)·10 citations
29. 29*

    Longitudinal flow decorrelation in heavy-ion collision at RHIC energies using a multi-phase transport model

    Prabhupada Dixit🇮🇳 · Md. Nasim🇮🇳

    We present a study on the longitudinal flow decorrelation in heavy-ion collisions at the RHIC Beam Energy Scan (BES) energies ($\sqrt{s_{NN}}$ = 11.5 to 200 GeV in Au+Au collisions) using the AMPT model. We measure the second and third order factorization ratios ($r_2$ and $r_3$) across BES energies, finding $r_2$ weakly dependent on collision energy while $r_3$ shows a more prominent collision energy dependent. The effect of parton-parton scattering cross section on $r_2$ and $r_3$ is studied which suggests that longitudinal decorrelation could be a potential observable to constrain transport properties of the medium. We also analyze the contributions of flow-plane and flow magnitude decorrelation, with flow-plane decorrelation being dominant. we measure a recently proposed observable, the four particle cumulant ($T_2$), which remains resilient to non-flow effects and exhibits sensitivity to different decorrelation patterns. Through the measurement of $T_2$, we consistently observe a hint of S-shaped or torqued decorrelation across all energy ranges in peripheral collisions (40-80\%). But in central and mid-central collisions, presence of any specific pattern of decorrelation is missing in AMPT model.

    hep-phhep-exnucl-th2 citations
30. 30*

    Asymptotic mass limit of large fully-heavy compact multiquarks

    M.C. Gordillo🇪🇸 · J.M Alcaraz-Pelegrina🇪🇸

    The properties of fully-heavy arrangements including a number of quarks between 5 and 12 were calculated within the framework of a constituent quark model by using a diffusion Monte Carlo technique. We considered only clusters in which all the quarks had the same mass, and whose number of particles and antiparticles were adequate to produce color singlets. All the multiquarks were in their lowest possible values of $L^2$ and $S^2$ operators. This means that we considered only color-spin wavefunctions that were antisymmetric with respect to the interchange of {\em any} two quarks of the same type. We found that in both all-$c$ and all-$b$ multiquarks, the mass per particle levels off for arrangements with a number of quarks larger of equal than six. The analysis of their structure implies that the fully-heavy multiquarks are compact structures.

    hep-phPRD(2023)·14 citations
31. 31*

    Parton cascades at DLA: the role of the evolution variable

    Carlota Andrés🇫🇷 · Liliana Apolinário🇵🇹 · Néstor Armesto🇪🇸 · André Cordeiro🇵🇹 · Fabio Dominguez🇪🇸 · José Guilherme Milhano🇵🇹

    While experimental studies on jet quenching have achieved a large sophistication, the theoretical description of this phenomenon still misses some important points. One of them is the interplay of vacuum-like emissions, usually formulated in momentum space, with the medium induced ones that demand an interplay with a space-time picture of the medium and thus must be formulated in position space. A unified description of both vacuum and medium-induced emissions is lacking. In this work, we compute the tree-level probability of a double gluon emission in vacuum, and identify the enhanced phase-space regions for each diagram, corresponding to different configurations of the parton cascade. This calculation provides a parametric form for the formation times associated with each diagram, highlighting the equivalence of various ordering variables at double logarithmic accuracy. This equivalence is further explored by building a toy Monte-Carlo parton shower ordered in formation time, virtuality, transverse momentum, and angle. Aiming at a link with jet substructure, we compute the Lund Plane distributions and trajectories for each ordering prescription. We also compute the distributions in number of splittings and final partons, with the goal of clarifying the differences to be expected from the different ordering variables and the vetoes that must be implemented at Monte Carlo level to conserve energy-momentum, which turn out to have a sizeable influence on the shower's evolution.

    hep-phPoS(2024)·0 citations
32. 32*

    Neutrino decoupling and the transition to cold dark matter

    Roman Schnabel🇩🇪

    About 40 years ago, the neutrino was ruled out as the dark matter particle based on several arguments. Here I use the well-established concept of quantum uncertainties of position and momentum to describe the decoupling of neutrinos from the primordial plasma, which took place about half a second after the Big Bang. In this way I show that the main arguments against the neutrino are either wrong or have loopholes, and conclude that the neutrino urgently needs to be reconsidered, not as a 'hot', but as the 'cold' dark matter particle.

    hep-phastro-ph.HEgr-qc0 citations
33. 33*

    Three-loop master integrals for H+jet production at N${}^3$LO: Towards the non-planar topologies

    Dhimiter D. Canko🇬🇷 · Nikolaos Syrrakos🇩🇪

    We discuss the recent progress that has been made towards the computation of three-loop non-planar master integrals relevant to next-to-next-to-next-to-leading-order (N${}^3$LO) corrections to processes such as H+jet production at the LHC. We describe the analytic structure of these integrals, as well as several technical issues regarding their analytic computation using canonical differential equations. Finally, we comment on the remaining steps towards the computation of all relevant three-loop topologies and their application to amplitude calculations.

    hep-phPoS(2024)·13 citations
34. 34*

    $k-$Dependent Dark Matter

    Parisa Arabameri🇮🇷 · Zahra Davari🇮🇷 · Nima Khosravi🇮🇷

    With the emersion of precise cosmology and the emergence of cosmic tensions, we are faced with the question of whether the simple model of cold dark matter needs to be extended and whether doing so can alleviate the tensions and improve our understanding of the properties of dark matter. In this study, we investigate one of the generalized models of dark matter so that the behavior of this dark matter changes according to the scale of $k$. In large scales (small $k$'s), the dark matter is cold, while it becomes warm for small scales (large $k$'s). This behavior is modeled phenomenologically for two different scenarios. We show that the $S_8$ tension can be alleviated, but the $H_0$ tension becomes milder while not too much.

    hep-phastro-ph.CO3 citations
35. 35*

    Towards UV-Models of Kinetic Mixing and Portal Matter IV: Quartification

    Thomas G. Rizzo🇺🇸

    As is well-known, Trinification, \ie, the extension of the Standard Model (SM) to $[SU(3){]}^3=SU(3{)}_c\times SU(3{)}_L\times SU(3{)}_R$ as occurs in $E_6$ models, allows for a partial unification of the gauge forces even though quarks and leptons remain in separate multiplets so that no heavy gauge or scalar fields exist which can generate proton decay. The extension of this idea to Quartification, by including an additional $SU(3{)}^{\prime }$ factor, has also been considered in the literature maintaining the basic attributes of Trinification but now allowing, \eg, for a more symmetric treatment of quarks and leptons at the price of new matter fields and gauge interactions. In this paper, we will consider this $SU(3{)}^{\prime }$ to be the `dark' gauge group, now containing the familiar $U(1{)}_D$ subgroup, under which the SM fields are all neutral, which is associated with kinetic mixing (KM) and the existence of a light, $\text{lsim}1$ GeV dark photon. This setup naturally predicts the existence of color-singlet portal matter (PM) fields, carrying both electromagnetic and $U(1{)}_D$ dark charges, that are necessary to generate this KM at the 1-loop level and whose masses are directly tied with those of the many new gauge bosons that originate from the extended gauge sector. In this paper, after a discussion of the detailed structure of this model, we present a broad survey of the collider phenomenology of the large set of new fields that must necessarily arise from this setup in a simplified version involving only a single generation of fermions. We demonstrate that several new signatures may be anticipated at the LHC as well as at future hadron and lepton colliders if such models are realized in nature.

    hep-phPRD(2023)·7 citations
36. 36*

    The linear response theory approach to the sub-GeV dark matter in the Sun

    Zheng-Liang Liang🇨🇳 · Ping Zhang🇨🇳

    In recent years, the importance of the electronic in-medium effect in the sub-GeV dark matter (DM) direct detection has been recognized and a coherent formulation of the DM-electron scattering based the linear response theory has been well established in the literature. In this paper, we apply the formulation to the scattering between DM particles and solar medium, and it is found that the dynamic structure factor inherently incorporate the particle-particle scattering and in-medium effect. Using this tool and taking a benchmark model as an example, we demonstrate how the in-medium effect affect the scattering of DM particles in the Sun, in both the heavy and light mediator limit. Formulae derived in this work lay the foundation for accurately calculating the spectra of solar-accelerated DM particles, which is of particular importance for the detection of DM particles via plasmon in semiconductor targets.

    hep-phJCAP(2023)·4 citations
37. 37*

    Hilbert series for ALP EFTs

    Christophe Grojean🇩🇪 · Jonathan Kley🇩🇪 · Chang-Yuan Yao🇨🇳

    Axions and axion-like particles (ALPs) are ubiquitous in popular attempts to solve supercalifragilisticexpialidocious puzzles of Nature. A widespread and vivid experimental programme spanning a vast range of mass scales and decades of couplings strives to find evidence for these elusive but theoretically well-motivated particles. In the absence of clear guiding principle, effective field theories (EFTs) prove to be an efficient tool in this experimental quest. Hilbert series technologies are a privileged instrument of the EFT toolbox to enumerate and classify operators. In this work, we compute explicitly the Hilbert series capturing the interactions of a generic ALP to the Standard Model particles above and below the electroweak symmetry scale, which allow us to build bases of operators up to dimension 8. In particular, we revealed a remarkable structure of the Hilbert series that isolates the shift-symmetry breaking and preserving interactions. In addition, with the Hilbert series method, we enumerate the sources of CP violation in terms of CP-even, CP-odd and CP-violating operators. Furthermore, we provide an ancillary file of the Hilbert series up to dimension 15 to supplement our findings, which can be used for further analysis and exploration.

    hep-phJHEP(2023)·29 citations
38. 38*

    Novel Search for Light Dark Photon in the Forward Experiments at the LHC

    Yeong Gyun Kim🇰🇷 · Kang Young Lee🇰🇷 · Soo-hyeon Nam🇰🇷

    We propose a novel approach for discovering a light dark photon in the forward experiments at the LHC, including the SND@LHC and the FASER experiments. Assuming the dark photon is lighter than twice the electron mass and feebly interacts with ordinary matter, it is long-lived enough to pass through 100 m of rock in front of the forward experiments and also through the detector targets. However, some portion of them could be converted into an electron-positron pair inside the detector through their interaction with the detector target, leaving an isolated electromagnetic shower as a clear new physics signature of the dark photon. With copiously produced dark photons from neutral pion decays in the forward region of the LHC, we expect to observe sizable events inside the detector. Our estimation shows that more than 10 signal events of the dark photon could be observed in the range of kinetic mixing parameter, $6.2\times 10^{-5}\lesssim ϵ\lesssim 2\times 10^{-1}$ and $3\times 10^{-5}\lesssim ϵ\lesssim 2\times 10^{-1}$ for dark photon mass $m_{A^{\prime }}\lesssim$ 1 MeV with integrated luminosities of 150 fb${}^{-1}$ and 3 ab${}^{-1}$, respectively.

    hep-phhep-exEPJC(2024)·2 citations
39. 39*

    Large Rapidity Gaps in proton-nucleus interaction

    V.A. Khoze🇬🇧 · M.G. Ryskin🇷🇺

    We analyse the cross-section of events with Large Rapidity Gaps observed in proton-lead collisions by the CMS collaboration. The role of the transverse size of elementary $pN$ amplitude is discussed. We emphasize that the cross-section of incoming proton dissociation caused by the photon radiated off the lead ion is close to the value of $d\sigma /d\Delta {\eta }^F$ measured by the CMS, and it is not clear why there is no room in the data for the Pomeron-induced contribution

    hep-phEPJC(2023)·1 citation
40. 40*

    Gauging the cosmic ray muon puzzle with the Forward Physics Facility

    Sergio J. Sciutto🇦🇷 · Luis A. Anchordoqui🇺🇸 · Carlos Garcia Canal🇦🇷 · Felix Kling🇩🇪 · Jorge F. Soriano (for the FPF Initiative)🇺🇸

    We investigate the observed muon deficit in air shower simulations when compared to ultrahigh-energy cosmic ray (UHECR) data. Gleaned from the observed enhancement of strangeness production in ALICE data, the associated $\pi \leftrightarrow K$ swap is taken as a cornerstone to resolve the muon puzzle via its corresponding impact on the shower evolution. We develop a phenomenological model in terms of the $\pi \leftrightarrow K$ swapping probability $F_s$. We provide a parametrization of $F_s(E^{(\mathrm{proj})},\eta )$ that can accommodate the UHECR data, where $E^{(\mathrm{proj})}$ is the projectile energy and $\eta$ the pseudorapidity. We also explore a future game plan for model improvement using the colossal amount of data to be collected by LHC neutrino detectors at the Forward Physics Facility (FPF). We calculate the corresponding sensitivity to $F_s$ and show that the FPF experiments will be able to probe the model phase space.

    hep-phPoS(2023)·9 citations
41. 41*

    Implications of Protecting the QCD Axion in the Dual Description

    Gongjun Choi🇨🇭 · Jacob Leedom🇩🇪

    The QCD axion can be be formulated in a dual description as a massive 2-form field. In this picture, the QCD axion quality problem translates into the question if there are additional 3-forms coupled to the axion other than the QCD 3-form that emerges at low energy. If such forms exist, the quality problem can be resolved via the introduction of other massive 2-forms (and thus corresponding axions), one for each additional 3-form. This can motivate an "axiverse from a high quality QCD axion". In this work, we discuss this issue in the general case where the QCD axion couples to arbitrarily many 3-forms. Given the multiple axion solution, we discuss the phenomenological implications of the enhanced quality of the QCD axion in the dual description. These include sub-eV axion-like particle search through the axion-photon coupling, the cosmological consistency of a large decay constant QCD axion, and a model for the observed cosmic birefringence.

    hep-phhep-thJHEP(2023)·12 citations
42. 42*

    Equation of State of Cold Quark Matter to $O({\alpha }_s^3\ln {\alpha }_s)$

    Tyler Gorda🇩🇪 · Risto Paatelainen🇫🇮 · Saga Säppi🇩🇪 · Kaapo Seppänen🇫🇮

    Accurately understanding the equation of state (EOS) of high-density, zero-temperature quark matter plays an essential role in constraining the behavior of dense strongly interacting matter inside the cores of neutron stars. In this Letter, we study the weak-coupling expansion of the EOS of cold quark matter and derive the complete, gauge-invariant contributions from the long-wavelength, dynamically screened gluonic sector at next-to-next-to-next-to-leading order (N3LO) in the strong coupling constant ${\alpha }_s$. This elevates the EOS result to the $O({\alpha }_s^3\ln {\alpha }_s)$ level, leaving only one unknown constant from the unscreened sector at N3LO, and places it on par with its high-temperature counterpart from 2003.

    hep-phastro-ph.HEnucl-thPRL(2023)·82 citations
43. 43*

    Computing Tools for Effective Field Theories

    Jason Aebischer🇨🇭 · Matteo Fael🇨🇭 · Javier Fuentes-Martín🇪🇸 · Anders Eller Thomsen🇨🇭 · Javier Virto🇪🇸 · Lukas Allwicher🇨🇭 · Supratim Das Bakshi🇪🇸 · Hermès Bélusca-Maïto🇭🇷 · Jorge de Blas🇪🇸 · Mikael Chala🇪🇸 · Juan Carlos Criado🇪🇸 · Athanasios Dedes🇬🇷 and 21 other authors

    In recent years, theoretical and phenomenological studies with effective field theories have become a trending and prolific line of research in the field of high-energy physics. In order to discuss present and future prospects concerning automated tools in this field, the SMEFT-Tools 2022 workshop was held at the University of Zurich from 14th-16th September 2022. The current document collects and summarizes the content of this workshop.

    hep-phhep-exEPJC(2024)·39 citations
44. 44*

    Intermittent QPO properties of MAXI J1820+070 revealed by Insight-HXMT

    P. Zhang🇨🇳 · R. Soria · S. Zhang🇨🇳 · L. Ji🇨🇳 · L. D. Kong · Y. P. Chen🇨🇳 · S. N. Zhang🇨🇳 · Z. Chang · M. Y. Ge · J. Li🇨🇳 · G. C. Liu🇨🇳 · Q. Z. Liu🇨🇳 and 9 other authors

    We investigate the dynamical properties of low frequency quasi-periodic oscillations (QPOs) observed from the black hole X-ray binary MAXI J1820+070 during the early part of its 2018 outburst, when the system was in a bright hard state. To this aim, we use a series of observations from the Hard X-ray Modulation Telescope Insight-HXMT, and apply a wavelet decomposition (weighted wavelet Z-transforms) to the X-ray light-curve. We find that the QPO phenomenon is intermittent within each individual observation, with some sub-intervals where the oscillation is strongly detected (high root-mean-square amplitude) and others where it is weak or absent. The average life time of individual QPO segments is ~ 5 oscillation cycles, with a 3 sigma tail up to ~ 20 cycles. There is no substantial difference between the energy spectra during intervals with strong and weak/absent QPOs. We discuss two possible reasons for the intermittent QPO strength, within the precessing jet model previously proposed for MAXI J1820+070. In the rigid precession model, intermittent QPOs are predicted to occur with a coherence Q ~ a few when the disk alignment time-scale is only a few times the precession time-scale. Alternatively, we suggest that changes in oscillation amplitude can be caused by changes in the jet speed. We discuss a possible reason for the intermittent QPO strength, within the precessing jet model previously proposed for MAXI J1820+070: we suggest that changes in oscillation amplitude are caused by changes in the jet speed. We argue that a misaligned, precessing jet scenario is also consistent with other recent observational findings that suggest an oscillation of the Compton reflection component in phase with the QPOs.

    ↳ astro-ph.HEhep-phAstron.Astrophys.(2023)·4 citations
45. 45*

    The Compton amplitude and nucleon structure functions in lattice QCD

    K. U. Can🇦🇺 · M. Batelaan🇦🇺 · A. Hannaford-Gunn🇦🇺 · R. Horsley🇬🇧 · Y. Nakamura🇯🇵 · H. Perlt🇩🇪 · P. E. L. Rakow🇬🇧 · G. Schierholz🇩🇪 · H. Stüben🇩🇪 · R. D. Young🇦🇺 · J. M. Zanotti🇦🇺

    The structure of hadrons relevant for deep-inelastic scattering are completely characterised by the Compton amplitude. A direct calculation of the Compton amplitude in a lattice QCD setup provides a way to accessing the structure functions, circumventing the operator mixing and renormalisation issues of the standard operator product expansion approach. In this contribution, we focus on the QCDSF/UKQCD Collaboration's advances in calculating the forward Compton amplitude via an implementation of the second-order Feynman-Hellmann theorem. We highlight our progress in investigating the moments of nucleon structure functions.

    ↳ hep-lathep-ph1 citation
46. 46*

    Lepton Flavour Universality tests in $b\to cl\nu$ decays at LHCb

    Rizwaan Mohammed🇬🇧

    The Standard Model predicts that the electroweak couplings to the three charged leptons are identical. However, in the last decade, experimental measurements have suggested that semileptonic processes involving taus could have a slightly enhanced decay rate compared to their muonic counterparts. If confirmed, this would be an unambiguous sign of New Physics, with various scenarios introducing additional interactions that couple preferentially to the third generation. Two recent lepton universality tests performed at LHCb are presented in this proceedings of the first edition of the New Frontiers in Lepton Flavour workshop.

    ↳ hep-exhep-phJINST(2023)·0 citations
47. 47*

    Stochastic gravitational wave background: birth from string-wall death

    Shuailiang Ge🇨🇳

    We study a new source of stochastic gravitational wave background (SGWB) from the final collapse of a network of topological defects. Typically, the final collapse is considered negligible for generating gravitational waves (GWs) due to its subdominance compared with the network's long-term evolution in the scaling regime. However, in some cases, a network can be driven outside of horizon by inflation and later re-enter horizon. Then, the network's final collapse after re-entering horizon becomes the dominant GW source and therefore cannot be neglected. We demonstrate this phenomenon in the context of $N_{\mathrm{DW}}=1$ string-wall networks which naturally arise in axion models, although the framework can be generalized to other types of topological networks. The final collapse of walls bounded by strings releases GWs. Our calculation of the corresponding GW spectrum suggests it could be related to the first few bins of the nano-Hertz SGWB signal possibly detected by various Pulsar Timing Array (PTA) collaborations. However, it is important to note that such GW spectrum falls within a relatively narrow frequency range, which may not completely account for the PTA signal that spans more than one order of magnitude in frequency. Furthermore, with different parameter choices, the resultant GWs generated in this mechanism could be probed by various GW interferometry experiments.

    ↳ gr-qcastro-ph.COastro-ph.HEhep-ex+1JCAP(2024)·39 citations
48. 48*

    Gauge Violation Spectroscopy in Synthetic Gauge Theories

    Hao-Yue Qi🇨🇳 · Wei Zheng🇨🇳

    Recently synthetic gauge fields have been implemented on quantum simulators. Unlike the gauge fields in the real world, in synthetic gauge fields, the gauge charge can fluctuate and gauge invariance can be violated, which leading rich physics unexplored before. In this work, we propose the gauge violation spectroscopy as a useful experimentally accessible measurement in the synthetic gauge theories. We show that the gauge violation spectroscopy exhibits no dispersion. Using three models as examples, two of them can be exactly solved by bosonization, and one has been realized in experiment, we further demonstrate the gauge violation spectroscopy can be used to detect the confinement and deconfinement phases. In the confinement phase, it shows a delta function behavior, while in the deconfinement phase, it has a finite width.

    ↳ cond-mat.quant-gashep-phPRResearch(2024)·10 citations
49. 49*

    Solution for cosmological observables in the Starobinsky model of inflation

    Gabriel German🇲🇽 · Juan Carlos Hidalgo🇲🇽 · Luis E. Padilla🇲🇽

    This paper focuses on the Starobinsky model of inflation. We derive solutions for various cosmological observables, such as the scalar spectral index $n_s$, the tensor-to-scalar ratio $r$ and their runnings, as well as the number of $e$-folds of inflation, reheating, and radiation with minimal assumptions. We establish an equation that connects inflation and reheating, which can be solved for the spectral index $n_s$. Using consistency relations of the model, we determine the other observables, the number of $e$-folds during inflation $N_k$, and the number of $e$-folds during reheating $N_{re}$. The impact of reheating on inflation is explored by constraining the equation of state parameter ${\omega }_{re}$ at the end of reheating. We find remarkable agreement between the Starobinsky model and current measurements of the power spectrum of primordial curvature perturbations and the present bounds on the spectrum of primordial gravitational waves.

    ↳ astro-ph.COgr-qchep-phEur.Phys.J.Plus(2024)·7 citations
50. 50*

    Energy Loss in Small Collision Systems

    Coleridge Faraday🇿🇦 · W. A. Horowitz🇿🇦

    We present leading hadron suppression predictions in $Pb+Pb$ and $p+Pb$ collisions from a convolved radiative and collisional energy loss model in which partons propagate through a realistic background, and in which the radiative energy loss receives a short pathlength correction. We find that the short pathlength correction is small for $D$ meson $R_{AA}(p_T)$ in both $Pb+Pb$ and $p+Pb$ collisions. However the short pathlength correction leads to a surprisingly large reduction in suppression for $\pi$ mesons in $p+Pb$ and even $Pb+Pb$ collisions, providing a qualitative explanation for the rapid rise in $\pi$ meson $R_{AA}(p_T)$ at the LHC. We find that the size of the short pathlength correction to $R_{AA}(p_T)$ is acutely sensitive to the chosen distribution of scattering centers in the plasma. Furthermore we find that conventional elastic energy loss models, which apply the central limit theorem to the number of scatterings, dramatically overpredict suppression in $\mathrm{p}+\mathrm{A}$ collisions, calling for short pathlength corrections to elastic energy loss.

    ↳ nucl-thhep-phPoS(2024)·3 citations
51. 51*

    Galois groups of uplifted de Sitter vacua

    Cesar Damian🇲🇽 · Oscar Loaiza-Brito🇲🇽

    We compute the Galois group of a polynomial whose roots are determined by the critical points of a scalar potential in type IIB compactifications. We focus our study on certain perturbative models where it is feasible to construct a de Sitter vacuum within the effective theory by introducing non-geometric fluxes, D-branes, or non-BPS states. Our findings clearly show that all de Sitter vacua derived from lifting AdS stable vacua are associated with an unsolvable Galois group. This suggests a deeper connection between the fundamental principles of Galois theory and its applications in the construction of dS vacua.

    ↳ hep-thhep-phAnnals Phys.(2024)·11 citations
52. 52*

    The future of cosmology? A case for CMB spectral distortions

    Matteo Lucca🇧🇪

    This thesis treats the topic of CMB Spectral Distortions (SDs), which represent any deviation from a pure black body shape of the CMB energy spectrum. As such, they can be used to probe the inflationary, expansion and thermal evolution of the universe both within $\Lambda$CDM and beyond it. The currently missing observation of this rich probe of the universe makes of it an ideal target for future observational campaigns. In fact, while the $\Lambda$CDM signal guarantees a discovery, the sensitivity to a wide variety of new physics opens the door to an enormous uncharted territory. In light of these considerations, the thesis opens by reviewing the topic of CMB SDs in a pedagogical and illustrative fashion, aimed at waking the interest of the broader community. This introductory premise sets the stage for the first main contribution of the thesis to the field of SDs: their implementation in the Boltzmann solver CLASS and the parameter inference code MontePython. The CLASS+MontePython pipeline is publicly available, fast, it includes all sources of SDs within $\Lambda$CDM and many others beyond that, and allows to consistently account for any observational setup. By means of these numerical tools, the second main contribution of the thesis consists in showcasing the versatility and competitiveness of SDs for several cosmological models as well as for a number of different mission designs. Among others, the results cover features in the primordial power spectrum, primordial gravitational waves, non-standard dark matter properties, primordial black holes, primordial magnetic fields and Hubble tension. Finally, the manuscript is disseminated with (20) follow-up ideas that naturally extend the work carried out so far, highlighting how rich of unexplored possibilities the field of CMB SDs still is. The hope is that these suggestions will become a propeller for further interesting developments.

    ↳ astro-ph.COgr-qchep-ph3 citations
53. 53*

    Canonical Ensemble vs. Grand Canonical Ensemble in the Description of Multicomponent Bosonic Systems

    D. Anchishkin🇺🇦 · V. Gnatovskyy🇺🇦 · D. Zhuravel🇺🇦 · V. Karpenko🇺🇦 · I. Mishustin🇩🇪 · H. Stoecker🇩🇪

    The thermodynamics of a system of interacting bosonic particles and antiparticles in the presence of the Bose-Einstein condensate is studied in the framework of the Skyrme-like mean-field model. It is assumed that the total charge density (isospin density) is conserved at all temperatures. Two cases are explicitly considered: zero and nonzero isospin charge of the system. A comparative analysis is carried out using Canonical Ensemble and Grand Canonical Ensemble. It is shown that the Grand Canonical Ensemble is not suitable for describing bosonic systems of particles and antiparticles in the presence of condensate.

    ↳ nucl-thhep-phquant-phUkr.J.Phys.(2024)·1 citation
54. 54*

    Gravitational wave signatures of no-scale Supergravity in NANOGrav and beyond

    Spyros Basilakos🇬🇷 · Dimitri V. Nanopoulos🇺🇸 · Theodoros Papanikolaou🇬🇷 · Emmanuel N. Saridakis🇬🇷 · Charalampos Tzerefos🇬🇷

    In this Letter, we derive for the first time a characteristic three-peaked GW signal within the framework of no-scale Supergravity, being the low-energy limit of Superstring theory. We concentrate on the primordial gravitational wave (GW) spectrum induced due to second-order gravitational interactions by inflationary curvature perturbations as well as by isocurvature energy density perturbations of primordial black holes (PBHs) both amplified due to the presence of an early matter-dominated era (eMD) era before Big Bang Nucleosythesis (BBN). In particular, we work with inflection-point inflationary potentials naturally-realised within Wess-Zumino type no-scale Supergravity and giving rise to the formation of microscopic PBHs triggering an eMD era and evaporating before BBN. Remarkably, we obtain an abundant production of gravitational waves at the frequency ranges of $\mathrm{nHz}$, $\mathrm{Hz}$ and $\mathrm{kHz}$ and in strong agreement with Pulsar Time Array (PTA) GW data. Interestingly enough, a simultaneous detection of all three $\mathrm{nHz}$, $\mathrm{Hz}$ and $\mathrm{kHz}$ GW peaks can constitute a potential observational signature for no-scale Supergravity.

    ↳ hep-thastro-ph.COgr-qchep-phPLB(2024)·85 citations
55. 55*

    Deconfinement, Center Symmetry and the Ghost Propagator in Landau Gauge Pure SU(3) Yang-Mills Theory

    V\'{\I}tor Paiva🇵🇹 · Paulo J. Silva🇵🇹 · Orlando Oliveira🇵🇹

    The temperature dependence of the Landau gauge ghost propagator is investigated in pure SU(3) Yang-Mills theory with lattice QCD simulations. Its behavior around the confined-deconfined phase transition temperature, $T_c\sim 270$ MeV, is investigated. The simulations show that in the deconfined phase, the ghost propagator is enhanced for small momenta, $\lesssim 1$ GeV. Furthermore, the analysis of the spontaneous breaking of center symmetry on the ghost propagator is studied. Similarly as observed for the gluon propagator, the simulations result in a decoupling of the sectors where the phase of the Polyakov loop is either 0 or $\pm 2\pi /3$ sectors, with the latter remaining indistinguishable. The results point to the possible use of the ghost propagator as an "order parameter" for the confined-deconfined phase transition.

    ↳ hep-lathep-phJHEP(2024)·3 citations
56. 56*

    Confronting sound speed resonance with pulsar timing arrays

    Jia-Heng Jin🇨🇳 · Zu-Cheng Chen🇨🇳 · Zhu Yi🇨🇳 · Zhi-Qiang You🇨🇳 · Lang Liu🇨🇳 · You Wu🇨🇳

    The stochastic signal detected by pulsar timing arrays (PTAs) has raised great interest in understanding its physical origin. Assuming the signal is a cosmological gravitational-wave background produced by overly large primordial curvature perturbations, we investigate the sound speed resonance effect with an oscillatory behavior using the combined PTA data from NANOGrav 15-yr data set, PPTA DR3, and EPTA DR2. We find that the stochastic signal can be explained by the induced gravitational waves sourced by the sound speed resonance mechanism, with the oscillation frequency $f_{\ast }\in [1.51,4.90]\times 10^{-7}$Hz and the start time of oscillation $|{\tau }_0|\in [2.05,106]\times 10^7$s

    ↳ astro-ph.COgr-qchep-phJCAP(2023)·73 citations
57. 57*

    Small-Scale Magnetic Fields are Critical to Shaping Solar Gamma-Ray Emission

    Jung-Tsung Li🇺🇸 · John F. Beacom🇺🇸 · Spencer Griffith🇺🇸 · Annika H. G. Peter🇺🇸

    The Sun is a bright gamma-ray source due to hadronic cosmic-ray interactions with solar gas. While it is known that incoming cosmic rays must generally first be reflected by solar magnetic fields to produce outgoing gamma rays, theoretical models have yet to reproduce the observed spectra. We introduce a simplified model of the solar magnetic fields that captures the main elements relevant to gamma-ray production. These are a flux tube, representing the network elements, and a flux sheet, representing the intergranule sheets. Both the tube and sheet have a horizontal size of order $100\mathrm{km}$ and serve as sites where cosmic rays are reflected and gamma rays are produced. While our simplified double-structure model does not capture all the complexities of the solar-surface magnetic fields, such as Alfvén turbulence from wave interactions or magnetic fluctuations from convection motions, it improves on previous models by reasonably producing both the hard spectrum seen by Fermi-LAT at $\text{1–200}\mathrm{GeV}$ and the considerably softer spectrum seen by HAWC at near $10^3\mathrm{GeV}$. We show that lower-energy ($\lesssim 10\mathrm{GeV}$) gamma rays are primarily produced in the network elements and higher-energy ($\gtrsim \mathrm{few}\times 10\mathrm{GeV}$) gamma rays in the intergranule sheets. Notably, the spectrum softening observed by HAWC results from the limited effectiveness of capturing and reflecting $\sim 10^4\mathrm{GeV}$ cosmic rays by the finite-sized intergranule sheets. Our study is important for understanding cosmic-ray transport in the solar atmosphere and will lead to insights about small-scale magnetic fields at the photosphere.

    ↳ astro-ph.HEastro-ph.SRhep-phApJ(2024)·15 citations
58. 58*

    New constraints on the gamma-ray and high energy neutrino fluxes from the circumstellar interaction of SN 2023ixf

    Prantik Sarmah🇮🇳

    The recent supernova, SN 2023ixf, one of the closest observed type II SNe has revealed the presence of a dense circumstellar material (CSM). Interaction of the SN ejecta with this dense CSM might create high energy protons of PeV energies through shock acceleration. These accelerated protons then colliding with the CSM (inelastic $pp$ collision) can produce secondaries such as high energy gamma-rays and neutrinos. However, no gamma-rays and neutrinos have been detected by Fermi-LAT and IceCube from this event. Fermi-LAT has placed an upper limit on the gamma-ray flux above $100$~MeV to be $2.6\times 10^{-11}\mathrm{erg}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$. On the other hand, IceCube's upper limit on muon neutrino flux is $7.3\times 10^{-2}\mathrm{GeV}\mathrm{c}{\mathrm{m}}^{-2}$. {\color{black} Taking these limits into account and using the shock-CSM properties derived from multi-wavelength observations, we obtain new upper limits on the gamma-ray ($10^{-11}\mathrm{erg}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$) and neutrino ($10^{-3}\mathrm{GeV}\mathrm{c}{\mathrm{m}}^{-2}$) fluxes from SN 2023ixf produced via the $pp$ interaction channel.} While we found the gamma-ray flux to be consistent with Fermi-LAT's upper limit, the neutrino flux is found to be about $2$ orders of magnitude smaller than the IceCube's upper limit. We further analyse the detection prospects of such secondary signals from future SN 2023 like events with upcoming detectors, CTA and IceCube-Gen2 and found to have great discovery potential, if any similar event occurs within $7$ Mpc.

    ↳ astro-ph.HEhep-phJCAP(2024)·22 citations
59. 59*

    Asymptotic Safety Guaranteed at Four Loop

    Daniel F. Litim🇬🇧 · Nahzaan Riyaz🇬🇧 · Emmanuel Stamou🇩🇪 · Tom Steudtner🇩🇪

    We investigate a family of four-dimensional quantum field theories with weakly interacting ultraviolet fixed points up to four loop order in perturbation theory. Key new ingredients are the three loop gauge contributions to quartic scalar beta functions, which we compute in the $\overline{\text{MS}}$ scheme for a template $SU(N_c)$ gauge theory coupled to $N_f$ fundamental fermions and elementary scalars. We then determine fixed point couplings, field and mass anomalous dimensions, and universal scaling exponents up to the first three non-trivial orders in a small Veneziano parameter. The phase diagram and UV-IR connecting trajectories are found and contrasted with asymptotic freedom. Further, the size of the conformal window, unitarity, and mechanisms leading to the loss of conformality are investigated. Our results provide blueprints for concrete 4d non-supersymmetric conformal field theories with standard model-like field content, and invite further model building.

    ↳ hep-thhep-phPRD(2023)·18 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.