Mon·May 29, 2023Monday·May 29, 2023

1. 01*

   Trinification from ${\mathrm{E}}_6$ symmetry breaking

   K.S. Babu🇺🇸 · Borut Bajc🇸🇮 · Vasja Susič🇨🇿

   In the context of ${\mathrm{E}}_6$ Grand Unified Theories (GUTs), an intriguing possibility for symmetry breaking to the Standard Model (SM) group involves an intermediate stage characterized by either $\mathrm{SU}(3)\times \mathrm{SU}(3)\times \mathrm{SU}(3)$ (trinification) or $\mathrm{SU}(6)\times \mathrm{SU}(2)$. The more common choices of $\mathrm{SU}(5)$ and $\mathrm{SO}(10)$ GUT symmetry groups do not offer such breaking chains. We argue that the presence of a real (rank $2$ tensor) representation $650$ of ${\mathrm{E}}_6$ in the scalar sector is the minimal and likely only reasonable possibility to obtain one of the novel intermediate stages. We analyze the renormalizable scalar potential of a single copy of the $650$ and find vacuum solutions that support regularly embedded subgroups $\mathrm{SU}(3)\times \mathrm{SU}(3)\times \mathrm{SU}(3)$, $\mathrm{SU}(6)\times \mathrm{SU}(2)$, and $\mathrm{SO}(10)\times \mathrm{U}(1)$, as well as specially embedded subgroups ${\mathrm{F}}_4$ and $\mathrm{SU}(3)\times {\mathrm{G}}_2$ that do not contain the SM gauge symmetry. We show that for a suitable choice of parameters, each of the regular cases can be obtained as the lowest among the analyzed minima in the potential.

   hep-phJHEP(2023)·9 citations
2. 02*

   Novel signals for the Type-X two Higgs doublet scenario at the Large Hadron Collider

   Biswarup Mukhopadhyaya🇮🇳 · Sirshendu Samanta🇮🇳 · Tousik Samui🇮🇳 · Ritesh K. Singh🇮🇳

   We consider, in the context of the Large Hadron Collider, the signals of the Type-X two Higgs doublet model (2HDM) in the parameter region answering to the best possible solution to the muon $(g-2)$ data within this framework. The analysis takes into account all theoretical and observational constraints, and is based on the final state comprising a same-sign dilepton pair and a pair of same-sign $\tau$ jets. The crucial ingredient in making the signal clean is the same-sign feature of both the dilepton and the $\tau$-jet pair individually. After a detailed estimate of the signal and all noteworthy backgrounds, we show that this channel offers by far the best signal significance among those studied so far, predicting discovery with an integrated luminosity of 3000 fb${}^{-1}$, and strong indications even with 1000 fb${}^{-1}$ if systematic uncertainies do not exceed about 10%. We also demonstrate that the recently developed dynamic radius jet algorithm is effective in this connection.

   hep-phhep-exPRD(2023)·4 citations
3. 03*

   Model independent analysis of femtoscopic correlation functions: An application to the $D_{s0}^{\ast }(2317)$

   Natsumi Ikeno🇯🇵 · Genaro Toledo🇲🇽 · Eulogio Oset🇪🇸

   We face the inverse problem of obtaining the interaction between coupled channels from the correlation functions of these channels. We apply the method to the interaction of the $D^0{K}^{+}$, $D^{+}{K}^0$, and $D_s^{+}\eta$ channels, from where the $D_{s0}^{\ast }(2317)$ state emerges. We use synthetic data extracted from an interaction model based on the local hidden gauge approach and find that the inverse problem can determine the existence of a bound state of the system with a precision of about 20 MeV. At the same time, we can determine the isospin nature of the bound state and its compositeness in terms of the channels. Furthermore, we evaluate the scattering length and effective range of all three channels, as well as the couplings of the bound state found to all the components. Lastly, the size parameter of the source function, $R$, which in principle should be a magnitude provided by the experimental teams, can be obtained from a fit to the data with relatively high accuracy. These findings show the value of the correlation function to learn about the meson-meson interaction for systems which are difficult to access in other present facilities.

   hep-phnucl-thPLB(2023)·64 citations
4. 04*

   Fermionic Electroweak NNLO Corrections to $e^{+}{e}^{-}\to ZH$ with Polarized Beams and Different Renormalization Schemes

   Ayres Freitas🇺🇸 · Qian Song🇺🇸 · Keping Xie🇺🇸

   Recently, the next-to-next-to-leading order (NNLO) electroweak corrections with fermion loops to the Higgsstrahling process were computed. Here we present numerical results for polarized electron/positron beams, as well as for two input parameter schemes known as the $\alpha (0)$ and $G_{\mu }$ schemes. The size of the NNLO corrections strongly depends on the beam polarization, leading to an increase of the $ZH$ cross-section by 0.76% for $e_{\mathrm{L}}^{+}{e}_{\mathrm{R}}^{-}$ beams, and a decrease of 0.04% for $e_{\mathrm{R}}^{+}{e}_{\mathrm{L}}^{-}$ beams. Furthermore, inclusion of the NNLO corrections is found to significantly reduce the discrepancy between the results in the $\alpha (0)$ and $G_{\mu }$ schemes. Using the remaining difference, together with other methods, the theory uncertainty from missing bosonic electroweak corrections is estimated to be less than 0.3%.

   hep-phPRD(2023)·10 citations
5. 05*

   Study lepton flavor violation $B^0\to {l_i}^{\pm }{l_j}^{\mp }$ within the Mass Insertion Approximation

   Yi-Tong Wang🇨🇳 · Jiao Ma🇨🇳 · Xing-Yu Han🇨🇳 · Xin-Xin Long🇨🇳 · Tong-Tong Wang🇨🇳 · Hai-Bin Zhang🇨🇳 · Shu-Min Zhao🇨🇳

   We study lepton flavor violating (LFV) decays $B^0\to {l_i}^{\pm }{l_j}^{\mp }$ ($B^0\to e\mu$, $B^0\to e\tau$ and $B^0\to \mu \tau$) in the $U(1{)}_X$SSM (SSM is acronym for the supersymmetric standard model), which is the $U(1{)}_X$ extension of the minimal supersymmetric standard model (MSSM). The local gauge group of $U(1{)}_X$SSM is $SU(3{)}_C\times SU(2{)}_L\times U(1{)}_Y\times U(1{)}_X$. These processes ($B^0\to e\mu$, $B^0\to e\tau$ and $B^0\to \mu \tau$) are strictly forbidden in the standard model (SM), but these LFV decays are a signal of new physics (NP). We use the Mass Insertion Approximation (MIA) to find sensitive parameters that directly influence the result of the branching ratio of LFV decay $B_d\to {l_i}^{\pm }{l_j}^{\mp }$. Combined with the latest experimental results, we analyze the relationship between different sensitive parameters and the branching ratios of the three processes. According to the numerical analysis, these elements are very restricted from the non observation of CLFV.

   hep-phJ.Phys.G(2024)·1 citation
6. 06*

   Prediction of charmed-bottom pentaquarks in quark model

   Ye Yan🇨🇳 · Yuheng Wu🇨🇳 · Hongxia Huang🇨🇳 · Jialun Ping🇨🇳 · Xinmei Zhu🇨🇳

   Inspired by the fully heavy tetraquark states reported by the LHCb, ATLAS and CMS Collaborations, we perform a systemical investigation of the low-lying fully heavy pentaquark systems composed of charm and bottom quarks (anti-quark) in the chiral quark model. With the help of the channel-coupling, we obtain several fully heavy pentaquark candidates, which are $cccc\bar{b}$ and $bbbb\bar{c}$ systems with $J^P=1/2^{-}$ and $3/2^{-}$, $cccb\bar{c}$, $bbbc\bar{b}$, $cccb\bar{b}$ and $bbbc\bar{c}$ systems with $J^P=5/2^{-}$. The binding energies of these states are all below 10 MeV and the root mean square (RMS) are around 1.8 fm, which indicates that these states are likely to be molecular states. These predicted exotic states may provide new ideas for experimental searches and we expect more experimental and theoretical researches to study and understand the fully heavy states in future.

   hep-phhep-exEPJC(2023)·7 citations
7. 07*

   Chemical freeze-out parameters via functional renormalization group approach

   Jun-xiang Shao🇨🇳 · Wei-jie Fu🇨🇳 · Yu-xin Liu🇨🇳

   We study the freeze-out parameters in a QCD-assisted effective theory that accurately captures the quantum and in-medium effects of QCD at low energies. Functional renormalization group approach is implemented in our work to incorporate the non-perturbative quantum, thermal and density fluctuations. By analyzing the calculated baryon number susceptibility ratios ${\chi }_2^B/{\chi }_1^B$ and ${\chi }_3^B/{\chi }_2^B$, we determine the chemical freeze-out temperatures and baryon chemical potentials in cases of hard thermal or dense loop improved $\mu$-dependent glue potential and $\mu$-independent glue potential. We calculate the ${\chi }_4^B/{\chi }_2^B(\kappa {\sigma }^2)$ and ${\chi }_6^B/{\chi }_2^B$ along the freeze-out line for both cases. It's found that $\kappa {\sigma }^2$ exhibits a nonmonotonic behavior in low collision energy region and approach to one for lower collision energy. ${\chi }_6^B/{\chi }_2^B$ shows a similar complicated behavior in our calculation.

   hep-phPRD(2024)·3 citations
8. 08*

   Effective Field Theories of Axion, ALP and Dark Photon

   Huayang Song🇨🇳 · Hao Sun🇨🇳 · Jiang-Hao Yu🇨🇳

   With the help of Young tensor technique, we enumerate the complete and independent set of effective operators up to $dim$-8 for the extension of the standard model with a Goldsonte boson by further imposing the Adler's zero condition in the soft momentum limit. Such basis can be reduced to describe the axion or majoron effective Lagrangian if further (symmetry) constraints are imposed. Then reformulating dark photon as combination of Goldstone boson and transverse gauge boson, the effective operators of the Goldstone boson can be extended to effective chiral Lagrangian description of the dark photon. For the first time we obtain 0 (0), 6 (44), 1 (1), 44 (356), 32 (520) operators in Goldstone effective field theory, and 9 (49), 0 (0), 108 (676), 10 (426), 1904 (40783) operators in dark photon effective field theory at the dimension 4, 5, 6, 7, 8 for one (three) generation of fermions.

   hep-phJHEP(2024)·24 citations
9. 09*

   How to Understand Limitations of Generative Networks

   Ranit Das🇺🇸 · Luigi Favaro🇩🇪 · Theo Heimel🇩🇪 · Claudius Krause🇩🇪 · Tilman Plehn🇩🇪 · David Shih🇺🇸

   Well-trained classifiers and their complete weight distributions provide us with a well-motivated and practicable method to test generative networks in particle physics. We illustrate their benefits for distribution-shifted jets, calorimeter showers, and reconstruction-level events. In all cases, the classifier weights make for a powerful test of the generative network, identify potential problems in the density estimation, relate them to the underlying physics, and tie in with a comprehensive precision and uncertainty treatment for generative networks.

   hep-phSciPost Phys.(2024)·56 citations
10. 10*

    Looking forward to inelastic DM with electromagnetic form factors at FASER and beam dump experiments

    Krzysztof Jodłowski🇰🇷

    Inelastic Dark Matter (iDM) is an interesting thermal DM scenario that can pose challenges for conventional detection methods. However, recent studies demonstrated that iDM coupled to a photon by electric or magnetic dipole moments can be effectively constrained by intensity frontier experiments using the displaced single-photon decay signature. In this work, we show that by utilizing additional signatures for such models, the sensitivity reach can be increased towards the short-lived regime, $\gamma c\tau \sim O(1)$m, which can occur in the region of the parameter space relevant to successful thermal freeze-out. These processes are secondary iDM production taking place by upscattering in front of the decay vessel and electron scattering. Additionally, we consider dimension-6 scenarios of photon-coupled iDM - the anapole moment and the charge radius operator - where the leading decay of the heavier iDM state is ${\chi }_1\to {\chi }_0{e}^{+}{e}^{-}$, resulting in a naturally long-lived ${\chi }_1$. We find that the decays of ${\chi }_1$ at FASER2, MATHUSLA, and SHiP will constrain these models more effectively than the scattering signature considered for the elastic coupling case, while secondary production yields similar constraints as the scattering.

    hep-phPRD(2023)·8 citations
11. 11*

    Signals of eV-scale sterile neutrino at long baseline neutrino experiments

    Sabila Parveen🇮🇳 · Kiran Sharma🇮🇳 · Sudhanwa Patra🇮🇳 · Poonam Mehta🇮🇳

    While most of the results of the neutrino oscillation experiments can be accommodated within the standard paradigm of three active flavor, there are tantalizing hints of an light eV-scale sterile neutrino from anomalous results of a few short baseline experiments. This additional light sterile neutrino is expected to leave an imprint on the physics observables pertaining to standard unknowns such as determination of the Dirac-type leptonic $CP$ phase, ${\delta }_{13}$, the question of neutrino mass hierarchy and the octant of ${\theta }_{23}$. The upcoming long baseline neutrino experiments such as T2HK, DUNE and P2O will be sensitive to active - sterile mixing. In the present work, we examine and assess the capability of these long baseline experiments to probe the sterile neutrino at the level of probabilities and event rates. We perform a detailed study by taking into account the values of parameters that are presently allowed and (a) study the impact on $CP$ violation by examining the role played by various appearance and disappearance channels, (b) address the question of disentangling the intrinsic effects from extrinsic effects in the standard paradigm as well as three active plus one light sterile neutrino, and finally (c) assess the ability of these long baseline experiments to distinguish between the two scenarios. Our results indicate that for the true values of sterile parameters and for all values of ${\delta }_{13}$, the sensitivity of P2O is the lowest while the sensitivity of T2HK is modest ($<3\sigma$) and the sensitivity of DUNE is $>3\sigma$. For larger values of the sterile mixing angles, there is an improvement in the sensitivity for all the three considered experiments.

    hep-phEPJC(2025)·7 citations
12. 12*

    Photon to axion conversion during Big Bang Nucleosynthesis

    Antonio J. Cuesta🇪🇸 · José I. Illana🇪🇸 · Manuel Masip🇪🇸

    We investigate how the resonant conversion at a temperature $\bar{T}=25$-$65$ keV of a fraction of the CMB photons into an axion-like majoron affects BBN. The scenario, that assumes the presence of a primordial magnetic field and the subsequent decay of the majorons into neutrinos at $T\approx 1$ eV, has been proposed to solve the $H_0$ tension. We find two main effects. First, since we lose photons to majorons at $\bar{T}$, the baryon to photon ratio is smaller at the beginning of BBN $(T>\bar{T})$ than during decoupling and structure formation ($T\ll \bar{T}$). This relaxes the $2\sigma$ mismatch between the observed deuterium abundance and the one predicted by the standard $\Lambda$CDM model. Second, since the conversion implies a sudden drop in the temperature of the CMB during the final phase of BBN, it interrupts the synthesis of lithium and beryllium and reduces their final abundance, possibly alleviating the lithium problem.

    hep-phastro-ph.COhep-thJCAP(2023)·7 citations
13. 13*

    Perturbative aspects of mass dimension one fermions non-minimally coupled to electromagnetic field

    Willian Carvalho🇧🇷 · M. Dias🇧🇷 · A. C. Lehum🇧🇷 · J. M. Hoff da Silva🇧🇷

    This paper addresses perturbative aspects of the renormalization of a fermion with mass dimension one non-minimally coupled to the electromagnetic field. Specifically, we calculate the one-loop corrections to the propagators and vertex functions of the model and determine the one-loop beta function of the non-minimal electromagnetic coupling. Additionally, we perform calculations of the two-loop corrections to the gauge field propagator, demonstrating that it remains massless and transverse up to this order. We also find that the non-minimal electromagnetic coupling can exhibit asymptotic freedom if a certain condition is satisfied. As a potential dark matter candidate, these findings suggest that the field may decouple at high energies. This aspect holds significance for calculating the relic abundance and freeze-out temperature of the field, particularly in relation to processes involving the ordinary particles of the Standard Model.

    hep-phhep-thEPL(2023)·4 citations
14. 14*

    Dirac-Majorana neutrino type oscillation induced by a wave dark matter

    YeolLin ChoeJo🇰🇷 · Yechan Kim🇰🇷 · Hye-Sung Lee🇰🇷

    Some properties of a neutrino may differ significantly depending on whether it is Dirac or Majorana type. The type is determined by the relative size of Dirac and Majorana masses, which may vary if they arise from an oscillating scalar dark matter. We show that the change can be significant enough to convert the neutrino type between Dirac and Majorana periodically while satisfying constraints on the dark matter. This neutrino type oscillation predicts periodic modulations in the event rates in various neutrino phenomena including the neutrinoless double beta decay. As the energy density and, thus, the oscillation amplitude of the dark matter evolves in the cosmic time scale, the neutrino masses change accordingly, which provides an interesting link between the present-time neutrino physics to the early universe cosmology including the leptogenesis.

    hep-phPRD(2023)·22 citations
15. 15*

    Sensitivity prospects for lepton-trijet signals in the $\nu$SMEFT at the LHeC

    Gabriel Zapata🇦🇷 · Tomás Urruzola🇺🇾 · Oscar A. Sampayo🇦🇷 · Lucía Duarte🇺🇾

    The observation of neutrino oscillations and masses motivates the extension of the standard model with right handed neutrinos, leading to heavy neutrino states possibly in the electroweak scale, which could be impacted by new high-scale weakly coupled physics. A systematic tool for studying these interactions is the neutrino-extended standard model effective field theory $\nu$SMEFT. In this work we study the prospects of the future LHeC electron-proton collider to discover or constrain the $\nu$SMEFT interactions, performing the first dedicated and realistic analysis of the well known lepton-trijet signals, both for the lepton flavor violating $p{e}^{-}\to {\mu }^{-}+3\mathrm{j}$ (LFV) and the lepton number violating $p{e}^{-}\to {\mu }^{+}+3\mathrm{j}$ (LNV) channels, for HNLs masses in the electroweak scale range: $100\mathrm{GeV}\le {\mathrm{m}}_{\mathrm{N}}\le 500\mathrm{GeV}$. The obtained sensitivity prospects show that the LHeC with $100\mathrm{f}{\mathrm{b}}^{-1}$ luminosity could be able to probe the scenario of a heavy $N$ and constrain the effective couplings to a region of the parameter space as tight as the bounds that are currently considered for the $\mathcal{O}(10)$GeV scale masses, with effective couplings of $\mathcal{O}(10^{-1})$ for NP scale $\Lambda =1\mathrm{TeV}$.

    hep-phEPJC(2024)·9 citations
16. 16*

    Cabibbo suppressed hyperon production off nuclei induced by antineutrinos

    M. Benitez Galan🇪🇸 · L. Alvarez-Ruso🇪🇸 · M. Rafi Alam🇮🇳 · I. Ruiz Simo🇪🇸 · M.J. Vicente Vacas🇪🇸

    In this work we study the production of $\Sigma$ and $\Lambda$ hyperons in strangeness changing $\Delta S=-1$ charged current interactions of muon antineutrinos on nuclear targets. At the nucleon level, besides quasielastic scattering we consider the inelastic mechanism in which a pion is produced alongside the hyperon. Its relevance for antineutrinos with energies below 2 GeV is conveyed in integrated and differential cross sections. We observe that the distributions on the angle between the hyperon and the final lepton are clearly different for quasielastic and inelastic processes. Hyperon final state interactions, modeled with an intranuclear cascade, lead to a significant transfer from primary produced $\Sigma$'s into final $\Lambda$'s. They also cause considerable energy loss, which is apparent in hyperon energy distributions. We have investigated $\Lambda$ production off ${}^{40}$Ar in the conditions of the recently reported MicroBooNE measurement. We find that the $\Lambda \pi$ contribution, dominated by ${\Sigma }^{\ast }(1385)$ excitation, accounts for about one third of the cross section.

    hep-phnucl-thPRD(2024)·4 citations
17. 17*

    Quantum Spread Complexity in Neutrino Oscillations

    Khushboo Dixit🇿🇦 · S. Shajidul Haque🇿🇦 · Soebur Razzaque🇿🇦

    Quantum information theory has recently emerged as a flourishing area of research and quantum complexity, one of its powerful measures, is being applied for investigating complex systems in many areas of physics. Its application to practical physical situations, however, is still few and far between. Neutrino flavor oscillation is a widely studied physical phenomena with far reaching consequences in understanding the standard model of particle physics and to search for physics beyond it. Oscillation arises because of mixing between the flavor and mass eigenstates, and their evolution over time. It is an inherent quantum system for which flavor transitions are traditionally studied with probabilistic measures. We have applied quantum complexity formalism as an alternate measure to study neutrino oscillations. In particular, quantum spread complexity revealed additional information on the violation of charge-parity symmetry in the neutrino sector. Our results indicate that complexity favors the maximum violation of charge-parity, hinted recently by experimental data.

    hep-phhep-exhep-thquant-phEPJC(2024)·15 citations
18. 18*

    Two-Loop QCD Corrections for Three-Photon Production at Hadron Colliders

    Samuel Abreu🇨🇭 · Giuseppe De Laurentis🇨🇭 · Harald Ita🇨🇭 · Maximillian Klinkert🇩🇪 · Ben Page🇨🇭 · Vasily Sotnikov🇨🇭

    We complete the computation of the two-loop helicity amplitudes for the production of three photons at hadron colliders, including all contributions beyond the leading-color approximation. We reconstruct the analytic form of the amplitudes from numerical finite-field samples obtained with the numerical unitarity method. This method requires as input surface terms for all relevant five-point non-planar integral topologies, which we obtain by solving the associated syzygy problem in embedding space. The numerical samples are used to constrain compact spinor-helicity ansätze, which are optimized by taking advantage of the known one-loop analytic structure. We make our analytic results available in a public C++ library, which is suitable for immediate phenomenological applications. We estimate that the inclusion of the subleading-color contributions will decrease the size of the two-loop corrections by about 30% to 50%, and the NNLO cross sections by a few percent, compared to the results in the leading-color approximation.

    hep-phSciPost Phys.(2023)·45 citations
19. 19*

    Fitting a Deep Generative Hadronization Model

    Jay Chan🇺🇸 · Xiangyang Ju🇺🇸 · Adam Kania🇵🇱 · Benjamin Nachman🇺🇸 · Vishnu Sangli🇺🇸 · Andrzej Siodmok🇵🇱

    Hadronization is a critical step in the simulation of high-energy particle and nuclear physics experiments. As there is no first principles understanding of this process, physically-inspired hadronization models have a large number of parameters that are fit to data. Deep generative models are a natural replacement for classical techniques, since they are more flexible and may be able to improve the overall precision. Proof of principle studies have shown how to use neural networks to emulate specific hadronization when trained using the inputs and outputs of classical methods. However, these approaches will not work with data, where we do not have a matching between observed hadrons and partons. In this paper, we develop a protocol for fitting a deep generative hadronization model in a realistic setting, where we only have access to a set of hadrons in data. Our approach uses a variation of a Generative Adversarial Network with a permutation invariant discriminator. We find that this setup is able to match the hadronization model in Herwig with multiple sets of parameters. This work represents a significant step forward in a longer term program to develop, train, and integrate machine learning-based hadronization models into parton shower Monte Carlo programs.

    hep-phhep-exphysics.data-anJHEP(2023)·44 citations
20. 20*

    Study of Kinematics of the Jets in VBS Process at the Large Hadron Collider

    Kadri Ozdemir🇹🇷

    The comparison of the kinematic properties of different Vector Boson Scattering (VBS) and Vector Boson Fusion (VBF) processes using multivariate discriminator is presented. The search is performed to identify common features in the the polarized $W^{\pm }{W}^{\pm }jj$ channel, mainly central and forward region jets kinematic variables such as eta, phi, mass and transverse energy, in order to determine some universal cuts. Traditionally boosted decision trees (BDT) are used as multivariate discriminator. The presented results are based on proton-proton collision Monte Carlo (MC) simulation samples center-of-mass energy 14 TeV and corresponding to an integrated luminosity of 3000 $f{b}^{-1}$. MC samples are generated using MADGRAPH and PYTHIA.

    ↳ hep-exhep-ph1 citation
21. 21*

    Intrinsic Angular Momentum of the B Mesons: Proposal for a Model-Independent Measurement

    M. P. Fewell🇦🇺

    The intrinsic angular momentum ("spin") of the B mesons has not so far been measured, notwithstanding the large amount of experimental attention that these particles have received in the four decades since the first of them was discovered. This paper draws attention to the applicability of a long-standing method for spin measurement from nuclear spectroscopy, concluding that known decay data point to the in-principle feasibility of a model-independent measurement of the spin of the B${}^{+}$ meson. For the B${}^0$ and B${}_{\mathrm{s}}^0$ mesons, known decay chains allow the Standard-Model prediction to be tested, but are insufficient for a fully model-independent spin measurement. Suitable decay chains are not yet known for the B${}_{\mathrm{c}}^{+}$ meson. The Standard Model predicts all B mesons to have spin zero. If this turns out not to be so, then the possibility of parity measurement opens up, using a related method.

    ↳ hep-exhep-ph0 citations
22. 22*

    Variation of the fine structure constant in the light of recent helium abundance measurement

    Osamu Seto🇯🇵 · Tomo Takahashi🇯🇵 · Yo Toda🇯🇵

    We point out that the recent result of primordial helium-4 (${}^4$He) abundance measurement by EMPRESS, which has reported a smaller ${}^4$He abundance than other measurements, can be well fitted by assuming a time-variation of the fine structure constant $\alpha$ which is slightly smaller than the present value during big bang nucleosynthesis (BBN). We find that the EMPRESS result in combination with deuterium abundance measurement indicates $-2.6\%<\Delta \alpha /\alpha <-1.4\%$ (68\% C.L.) where $\Delta \alpha$ is the difference between the values of $\alpha$ at the BBN and present epochs, while $-1.2\%<\Delta \alpha /\alpha <0.4\%$ (68\% C.L.) is obtained from other previous ${}^4$He abundance data. We also investigate its effects in the framework where the effective number of neutrino species and the lepton asymmetry, which are other typical interpretations of the EMPRESS result, are allowed to vary. Once a smaller $\alpha$ is adopted, the EMPRESS result can be explained without assuming any non-standard values for the effective number of neutrino species and lepton asymmetry.

    ↳ astro-ph.COgr-qchep-phPRD(2023)·17 citations
23. 23*

    Zero-modes in magnetized $T^6/{\mathbb{Z}}_N$ orbifold models through $Sp(6,\mathbb{Z})$ modular symmetry

    Shota Kikuchi🇯🇵 · Tatsuo Kobayashi🇯🇵 · Kaito Nasu🇯🇵 · Shohei Takada🇯🇵 · Hikaru Uchida🇯🇵

    We study of fermion zero-modes on magnetized $T^6/{\mathbb{Z}}_N$ orbifolds. In particular, we focus on non-factorizable orbifolds, i.e. $T^6/{\mathbb{Z}}_7$ and $T^6/{\mathbb{Z}}_{12}$ corresponding to $SU(7)$ and $E_6$ Lie lattices respectively. The number of degenerated zero-modes corresponds to the generation number of low energy effective theory in four dimensional space-time. We find that three-generation models preserving 4D $\mathcal{N}=1$ supersymmetry can be realized by magnetized $T^6/{\mathbb{Z}}_{12}$, but not by $T^6/{\mathbb{Z}}_7$. We use $Sp(6,\mathbb{Z})$ modular transformation for the analyses.

    ↳ hep-thhep-phPRD(2023)·17 citations
24. 24*

    Pulsar as a Weber detector of gravitational waves and a probe to its internal phase transitions

    Partha Bagchi🇮🇳 · Oindrila Ganguly🇮🇳 · Biswanath Layek🇮🇳 · Anjishnu Sarkar🇮🇳 · Ajit M. Srivastava🇮🇳

    It is believed that cores of neutron stars provide a natural laboratory where exotic high baryon density QCD phases may exist.The theoretically well established {\it neutron superfluid phase} is also believed to be found only inside neutron stars. Focus on neutron stars has intensified in recent years with the direct detection of gravitational waves (GWs) from binary neutron star (BNS) merger, which has allowed the possibility of directly probing the properties of the interior of a neutron star. A remarkable phenomenon manifested by rapidly rotating neutron stars is in their {\it avatar} as {\it Pulsars}. The accuracy of pulsar timing allowed the first indirect detection of GWs from a BNS system and opened up a few exciting possibilities. Any pulsar deformation, even if incredibly tiny, can leave imprints on the pulses by introducing tiny perturbations of the moment of inertia (MI) tensor components. While the diagonal MI components of the perturbed MI tensor affect the pulse timings, the off-diagonal components lead to the pulsar's wobbling and affecting the pulse profile. This opens up an opportunity to explore various phase transitions inside a pulsar core by induced density fluctuations through the observable effects on the pulse timing and profile. Such perturbations also naturally induce a rapidly changing quadrupole moment of the star, thereby providing a new source of GW emission. Another remarkable possibility arises when we consider the effect of an external GW on a neutron star. With the possibility of detecting any minute changes in its configuration through pulse observations, the neutron star has the potential to perform as a Weber detector of GWs. This brief review focuses on these specific aspects of a pulsar, specifically on the type of physics that can be probed by utilizing the effect of changes in the MI tensor on pulse properties.

    ↳ astro-ph.HEhep-phnucl-exnucl-thMod.Phys.Lett.A(2024)·5 citations
25. 25*

    Confinement and Deconfinement in Gauge Theories: A Quantum Field Theory

    A. P. Balachandran🇺🇸

    After a brief recount of small and large gauge transformations and the nature of observables, we discuss superselection sectors in gauge theories. There are an infinity of them, classified by large gauge transformations. Gauge theory sectors are labelled by the eigenvalues of a complete commuting set (CCS) of these transformations. In QED, the standard chemical potential is one such operator generating global U(1). There are many more given by the moments of the electric field on the sphere at infinity. In QCD, the CCS are constructed from the two commuting generators spanning a Cartan subalgebra. Large gauge transformations commute with the Hamiltonian and preserve the equations of motion. They form an infinite number of `classical symmetries'. But most of them are anamolous changing the superselection sectors. We show that any element of a large gauge transformation can be added to the standard Hamiltonian as a generalised chemical potential without changing field equations and that in QCD, they lead to confined and deconfined phases . A speculation about the physical meaning of these chemical potentials is also made.

    ↳ hep-thhep-phMod.Phys.Lett.A(2024)·1 citation
26. 26*

    The First LHAASO Catalog of Gamma-Ray Sources

    Zhen Cao · F. Aharonian · Q. An · Axikegu · Y.X. Bai · Y.W. Bao · D. Bastieri · X.J. Bi · Y.J. Bi · J.T. Cai · Q. Cao · W.Y. Cao and 268 other authors

    We present the first catalog of very-high energy and ultra-high energy gamma-ray sources detected by the Large High Altitude Air Shower Observatory (LHAASO). The catalog was compiled using 508 days of data collected by the Water Cherenkov Detector Array (WCDA) from March 2021 to September 2022 and 933 days of data recorded by the Kilometer Squared Array (KM2A) from January 2020 to September 2022. This catalog represents the main result from the most sensitive large coverage gamma-ray survey of the sky above 1 TeV, covering declination from $-$20${}^{\circ }$ to 80${}^{\circ }$. In total, the catalog contains 90 sources with an extended size smaller than $2^{\circ }$ and a significance of detection at $>5\sigma$. Based on our source association criteria, 32 new TeV sources are proposed in this study. Among the 90 sources, 43 sources are detected with ultra-high energy ($E>100$ TeV) emission at $>4\sigma$ significance level. We provide the position, extension, and spectral characteristics of all the sources in this catalog.

    ↳ astro-ph.HEhep-phAstrophys.J.Suppl.(2024)·417 citations
27. 27*

    Black Hole Extremality in Nonlinear Electrodynamics: A Lesson for Weak Gravity and Festina Lente Bounds

    Yoshihiko Abe🇺🇸 · Toshifumi Noumi🇯🇵 · Kaho Yoshimura🇯🇵

    We study black hole extremality in nonlinear electrodynamics motivated by the Weak Gravity Conjecture (WGC) and the Festina Lente (FL) bound. For illustration, we consider the Euler-Heisenberg model and the Dirac-Born-Infeld model in asymptotically flat spacetime, de Sitter spacetime, and anti-de Sitter spacetime. We find that in all cases the extremal condition enjoys a certain monotonicity expected by the WGC. This provides evidence for the conjecture beyond the leading order corrections to the Einstein-Maxwell theory. We also study how light charged particles modify the mass-charge relation of Nariai black holes in de Sitter spacetime and discuss possible implications for the FL bound. Besides, we point out an interesting similarity between our black hole analysis and gravitational positivity bounds on scattering amplitudes.

    ↳ hep-thgr-qchep-phJHEP(2023)·19 citations
28. 28*

    Is Gauge Mediation in the Swampland?

    Ioannis Dalianis🇬🇷 · Fotis Farakos🇮🇹 · Alex Kehagias🇬🇷

    We note that the typical gauge mediation of supersymmetry breaking is in tension with the global limit of the festina lente swampland bound. The alternatives are mediation/breaking schemes that decouple together with gravity, as for example gravity mediation, for which we highlight some basic phenomenological properties. Gauge mediation remains instead a viable mechanism only in models where supersymmetry is restored in the global limit, as for example in no-scale supergravity.

    ↳ hep-thhep-phPLB(2023)·4 citations
29. 29*

    Sphaleron rate from a modified Backus-Gilbert inversion method

    Claudio Bonanno🇪🇸 · Francesco D'Angelo🇮🇹 · Massimo D'Elia🇮🇹 · Lorenzo Maio🇮🇹 · Manuel Naviglio🇮🇹

    We compute the sphaleron rate in quenched QCD for a temperature $T\simeq 1.24T_c$ from the inversion of the Euclidean lattice time correlator of the topological charge density. We explore and compare two different strategies: one follows a new approach proposed in this study and consists in extracting the rate from finite lattice spacing correlators, and then in taking the continuum limit at fixed smoothing radius followed by a zero-smoothing extrapolation; the other follows the traditional approach of extracting the rate after performing such double extrapolation directly on the correlator. In both cases the rate is obtained from a recently-proposed modification of the standard Backus-Gilbert procedure. The two strategies lead to compatible estimates within errors, which are then compared to previous results in the literature at the same or similar temperatures; the new strategy permits to obtain improved results, in terms of statistical and systematic uncertainties.

    ↳ hep-lathep-phhep-thPRD(2023)·34 citations
30. 30*

    Limits from the grave: resurrecting Hitomi for decaying dark matter and forecasting leading sensitivity for XRISM

    Christopher Dessert🇺🇸 · Orion Ning🇺🇸 · Nicholas L. Rodd🇨🇭 · Benjamin R. Safdi🇺🇸

    The Hitomi X-ray satellite mission carried unique high-resolution spectrometers that were set to revolutionize the search for sterile neutrino dark matter (DM) by looking for narrow X-ray lines arising from DM decays. Unfortunately, the satellite was lost shortly after launch, and to-date the only analysis using Hitomi for DM decay used data taken towards the Perseus cluster. In this work we present a significantly more sensitive search from an analysis of archival Hitomi data towards blank sky locations, searching for DM decaying in our own Milky Way. The soon-to-be-launched XRISM satellite will have nearly identical soft-X-ray spectral capabilities to Hitomi; we project the full-mission sensitivity of XRISM for analyses of their future blank-sky data, and we find that XRISM will have the leading sensitivity to decaying DM for masses between roughly 1 to 20 keV, with important implications for sterile neutrino and heavy axion-like particle DM scenarios.

    ↳ astro-ph.COastro-ph.HEhep-phPRL(2024)·27 citations
31. 31*

    Wave scattering event shapes at high energies

    Riccardo Gonzo🇬🇧 · Anton Ilderton🇬🇧

    We study the space and properties of global and local observables for radiation emitted in the scattering of a massive scalar field in gauge and gravitational plane-wave backgrounds, in both the quantum and classical theory. We first compute the radiated momentum and angular momentum flow, demonstrating that they are good local observables determined by the amplitude and phase of the waveform. We then focus on the corresponding global observables, which in the gravitational case requires dealing with the collinear divergence of the gravitational Compton cross-section. We show using the KLN theorem that we can obtain an infrared-finite cross-section only by summing over forward scattering diagrams; this suggests dressing the initial state in the direction collinear to the plane wave in order to be able to compute observables integrated over the celestial sphere. Finally, we explore the high-energy behaviour of our observables. We find that classical global observables generically exhibit a power-law mass divergence in electrodynamics and a logarithmic mass divergence in gravity, even when radiation reaction is included. We then show explicitly how this is consistently resolved in the full quantum theory.

    ↳ hep-thgr-qchep-phJHEP(2023)·17 citations
32. 32*

    Shadow Behavior of the Quantum-Corrected Schwarzschild Black Hole Immersed in Holographic Quintessence

    Sara Saghafi🇮🇷 · Kourosh Nozari🇮🇷

    In this paper, we aim to explore the impact of the Planck scale corrections and the Holographic quintessence on the shadow behavior of non-rotating black holes. To do this, we consider the quantum-corrected Schwarzschild black hole surrounded by the quintessence field inspired by the Kazakov-Solodukhin and the Kiselev ideas, and we call this combination the Kazakov-Solodukhin-Kiselev (KSK) black hole. We conclude that the quintessence field as the candidate of dark energy in the black hole can be interpreted as Holographic quintessence. To find the geodesic equations of the black hole, we employ the Hamilton-Jacobi approach and also, the Carter procedure. We discover that the size of the shadow of this black hole, which depends on its central mass, is also determined by the Planck scale effects and Holographic quintessence.

    ↳ hep-thhep-phJHAP(2022)·21 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.