Wed·May 8, 2024Wednesday·May 8, 2024

1. 01*

   Higgs Portal Dark Matter Freeze-in at Stronger Coupling: Observational Benchmarks

   Giorgio Arcadi🇮🇹 · Francesco Costa🇩🇪 · Andreas Goudelis🇫🇷 · Oleg Lebedev🇫🇮

   We study freeze-in production of Higgs portal dark matter (DM) at temperatures far below the dark matter mass. The temperature of the Standard Model (SM) thermal bath may have never been high such that dark matter production via thermal emission has been Boltzmann suppressed. This allows for a significant coupling between the Higgs field and DM, which is being probed by the direct DM detection experiments and invisible Higgs decay searches at the LHC. We delineate the corresponding parameter space in the Higgs portal framework with dark matter of spin 0, 1/2 and 1.

   hep-phJHEP(2024)·52 citations
2. 02*

   Charged lepton-flavor violating constraints to non-unitarity in the Linear Seesaw scheme

   Jesus Miguel Celestino-Ramirez🇲🇽 · O. G. Miranda🇲🇽

   We analyze the non-unitary effects in the linear seesaw mechanism using the current constraints and future sensitivity of the charged Lepton Flavor Violation (cLFV) processes. We perform a random scan confronting the non-unitary parameters with the limits to the cLFV processes. We show our results for the normal and inverted ordering of the oscillation data. We also discuss the equivalence of different parametrizations of the non-unitary mixing matrix and show our results in terms of the different parameterizations. We found that the stronger restrictions in the non-unitary parameter space come from rare muon decay searches.

   hep-phhep-exNPB(2025)·5 citations
3. 03*

   Remark on neutrino oscillations

   Kazuo Fujikawa🇯🇵

   The oscillations of ultra-relativistic neutrinos are realized by the propagation of assumed zero-mass on-shell neutrinos with the speed of light in vacuum combined with the phase modulation by the small mass term $\exp [-i(m_{{\nu }_k}^2/2|\vec{p}|)\tau ]$ with a time parameter $\tau$. This picture is realized in the first quantization by the mass expansion and in field theory by the use of $\delta (x^0-y^0-\tau )⟨0|T^{\star }{\nu }_{Lk}(x)\overline{{\nu }_{Lk}(y)}|0⟩$ with the neutrino mass eigenstates ${\nu }_{Lk}$ and a finite positive $\tau$ after the contour integral of the propagating neutrino energies. By noting that the conventional detectors are insensitive to neutrino masses, the measured energy-momenta of the initial and final states with assumed zero-mass neutrinos are conserved. The propagating neutrinos preserve the three-momentum in this sense but the energies of the massive neutrinos are conserved up to uncertainty relations and thus leading to oscillations. Conceptual complications in the case of Majorana neutrinos due to the charge conjugation in $d=4$ are also discussed.

   hep-phEPJC(2024)·1 citation
4. 04*

   Collapse of Neutrino Wave Functions under Penrose Gravitational Reduction

   B.J.P. Jones🇺🇸 · O.H. Seidel🇺🇸

   Models of spontaneous wave function collapse have been postulated to address the measurement problem in quantum mechanics. Their primary function is to convert coherent quantum superpositions into incoherent ones, with the result that macroscopic objects cannot be placed into widely separated superpositions for observably prolonged times. Many of these processes will also lead to loss of coherence in neutrino oscillations, producing observable signatures in the flavor profile of neutrinos at long travel distances. The majority of studies of neutrino oscillation coherence to date have focused on variants of the continuous state localization model, whereby an effective decoherence strength parameter is used to model the rate of coherence loss with an assumed energy dependence. Another class of collapse models that have been proposed posit connections to the configuration of gravitational field accompanying the mass distribution associated with each wave function that is in the superposition. A particularly interesting and prescriptive model is Penrose's description of gravitational collapse which proposes a decoherence time $\tau$ determined through $E_g\tau \sim \hslash$, where $E_g$ is a calculable function of the Newtonian gravitational potential. Here we explore application of the Penrose collapse model to neutrino oscillations, reinterpreting previous experimental limits on neutrino decoherence in terms of this model. We identify effects associated with both spatial collapse and momentum diffusion, finding that the latter is ruled out in data from the IceCube South Pole Neutrino Observatory so long as the neutrino wave packet width at production is ${\sigma }_{\nu ,x}\le 2\times 10^{-12}$ m.

   hep-phgr-qcPRD(2024)·1 citation
5. 05*

   Baryonic thermal screening mass at NLO

   Leonardo Giusti🇮🇹 · M. Laine🇨🇭 · Davide Laudicina🇮🇹 · Michele Pepe🇮🇹 · Pietro Rescigno🇮🇹

   We determine the resummed 1-loop correction to a baryonic thermal screening mass. The calculation is carried out in the framework of a dimensionally reduced effective theory, where quarks are heavy fields due to their non-zero Matsubara frequencies. The correction due to interactions is computed at O($g_{}^2$) in the coupling constant. In order to solve a 3-body Schrödinger equation, we exploit a two-dimensional generalization of the hyperspherical harmonics method. At electroweak scale temperatures, the NLO correction represents a $\sim 4.6\%$ increase of the free-theory value $3\pi T$ of the screening mass.

   hep-phhep-latJHEP(2024)·7 citations
6. 06*

   Finite modular majoron

   Tae Hyun Jung🇰🇷 · Junichiro Kawamura🇰🇷

   We point out that the accidental $U(1{)}_{B-L}$ symmetry can arise from a finite modular symmetry ${\Gamma }_N$ in the type-I seesaw. The finite modular symmetry is spontaneously broken in such a way that the residual ${\mathbb{Z}}_N^T$ discrete symmetry, associated with the $T$-transformation which shifts the modulus $\tau \to \tau +1$, remains unbroken. This discrete ${\mathbb{Z}}_N^T$ symmetry mimics $U(1{)}_{B-L}$, and hence the majoron appears as a pseudo Nambu-Goldstone boson of $U(1{)}_{B-L}$. Without introducing additional interactions, the modulus $\tau$ can be stabilized by the Coleman-Weinberg (CW) potential given by the Majorana mass terms of the right-handed neutrinos. We study cosmological implications of the majoron, with particular interests in the dark matter and dark radiation, where the latter may alleviate the Hubble tension. We also find that the CW potential can have a wide range of nearly exponential shape which prevents $\tau$ from overshooting, and makes the amount of dark radiation not too large.

   hep-phastro-ph.COhep-exhep-thJHEP(2024)·4 citations
7. 07*

   Lam-Tung relation breaking in $Z$ boson production as a probe of SMEFT effects

   Xu Li🇨🇳 · Bin Yan🇨🇳 · C.-P. Yuan🇺🇸

   The violation of Lam-Tung relation in the high-$p_T^{\ell \ell }$ region of the Drell-Yan process at the LHC presents a long-standing discrepancy with the standard model prediction at $\mathcal{O}({\alpha }_s^3)$ accuracy. In this Letter, we employed a model-independent analysis to investigate this phenomenon within the framework of the Standard Model Effective Field Theory (SMEFT). Our findings revealed that the leading contributions from SMEFT to this violation appear at the $1/{\Lambda }^4$ order with $\mathcal{O}({\alpha }_s)$ accuracy in QCD interaction. Notably, we demonstrated that the quadratic effect of dimension-6 dipole operators, associated with the $Z$ boson, dominates the breaking effects induced by various dimension-6 and dimension-8 operators. This provides a possible explanation for the observed discrepancy with the Standard Model predictions at the LHC. Furthermore, the breaking effects could also serve as a powerful tool for constraining $Z$-boson dipole interactions, highlighting their importance among potential sources of new physics in the Drell-Yan process.

   hep-phhep-exPRD(2025)·18 citations
8. 08*

   The ground states and first radial excitations of the vector tetraquark states with explicit P-waves via the QCD sum rules

   Zhi-Gang Wang🇨🇳

   In this work, we choose the diquark-antidiquark type four-quark currents with an explicit P-wave between the diquark and antidiquark pairs to study the ground states and first radial excitations of the hidden-charm tetraquark states with the quantum numbers $J^{PC}=1^{--}$. And we obtain the lowest vector tetraquark masses and make possible assignments of the existing $Y$ states. There indeed exists a hidden-charm tetraquark state with the $J^{PC}=1^{--}$ at the energy about $4.75\mathrm{GeV}$ as the first radial excitation to account for the BESIII data.

   hep-phCPC(2024)·9 citations
9. 09*

   Constraining the mass-spectra in the presence of a light sterile neutrino from absolute mass-related observables

   Srubabati Goswami🇮🇳 · Debashis Pachhar🇮🇳 · Supriya Pan🇮🇳

   The framework of three-flavor neutrino oscillation is a well-established phenomenon, but results from the short-baseline experiments, such as the Liquid Scintillator Neutrino Detector (LSND) and MiniBooster Neutrino Experiment (MiniBooNE), hint at the potential existence of an additional light neutrino state characterized by a mass-squared difference of approximately $1\mathrm{e}{\mathrm{V}}^2$. The new neutrino state is devoid of all Standard Model (SM) interactions, commonly referred to as a 'sterile' state. In addition, a sterile neutrino with a mass-squared difference of $10^{-2}$ $\mathrm{e}{\mathrm{V}}^2$ has been proposed to improve the tension between the results obtained from the Tokai to Kamioka (T2K) and the NuMI Off-axis ${\nu }_e$ Appearance (NO$\nu$A) experiments. Further, the non-observation of the predicted upturn in the solar neutrino spectra below 8 MeV can be explained by postulating an extra light sterile neutrino state with a mass-squared difference around $10^{-5}\mathrm{e}{\mathrm{V}}^2$. The hypothesis of an additional light sterile neutrino state introduces four distinct mass spectra depending on the sign of the mass-squared difference. In this paper, we discuss the implications of the above scenarios on the observables that depend on the absolute mass of the neutrinos, namely the sum of the light neutrino masses $(\Sigma )$ from cosmology, the effective mass of the electron neutrino from beta decay $(m_{\beta })$, and the effective Majorana mass $(m_{\beta \beta })$ from neutrinoless double beta decay. We show that some scenarios can be disfavored by the current constraints of the above variables. The implications for projected sensitivity of Karlsruhe Tritium Neutrino Experiment (KATRIN) and future experiments like Project-8, next Enriched Xenon Observatory (nEXO) have been discussed.

   hep-phPRD(2024)·4 citations
10. 10*

    Self-Similar Properties of the Proton Structure at Low x within the \textbf{xFitter} framework

    Shahin Atashbar Tehrani🇮🇷 · Fatemeh Taghavi Shahri🇮🇷 · Samira Shoeibi Mohsenabadi🇮🇷

    The structure of the proton exhibits Fractal behavior at low \textit{x}, where \textit{x} is the fraction of the proton's momentum carried by the interacting partons. This Fractal behavior is characterized by self-similar properties at different scales and can be quantified using the concept of Fractal dimension. An investigation into the Fractal properties of the proton structure at low \textit{x} is critical for understanding the fundamental properties of the strong force and developing a more comprehensive understanding of the hadron structure. Fractals, characterized by self-similar patterns across scales, demonstrate a direct correlation between their Fractal dimension and entropy, where higher Fractal dimensions correspond to increased informational content. Furthermore, it is essential for designing high-energy physics experiments and developing more accurate models of subatomic particle interactions. This paper has a fresh look at the self-similar properties of the proton structure at low \textit{x}. Our study involves the use of the \textbf{xFitter} framework to parameterize the proton structure functions with a Fractal formalism at low \textit{x}. We also examine how the inclusion of new data affects the results of our analysis.

    hep-phJHAP(2024)·1 citation
11. 11*

    Probing the polarized photon content of the proton in $ep$ collisions at the EIC

    Daniel Rein🇩🇪 · Marc Schlegel🇩🇪 · Werner Vogelsang🇩🇪

    We study the single-inclusive production of prompt photons in electron proton collisions, $ep\to \gamma X$, for kinematics relevant at the Electron-Ion Collider (EIC). We perform a perturbative calculation of the differential cross section to next-to-leading order in QCD and to lowest order in QED. We consider unpolarized collisions as well as scattering of longitudinally polarized incident electrons and protons. We show that the cross sections are sensitive to the parton distribution functions of photons inside the proton, which we find to generate the dominant contributions in certain kinematical regions at the EIC. We also investigate the effects of photon isolation on the unpolarized and polarized cross sections.

    hep-phhep-exPRD(2024)·8 citations
12. 12*

    Investigations on the weak decays of $D\bar{B}$ molecules

    Ming-Zhu Liu🇨🇳 · Li-Sheng Geng🇨🇳

    The decays of exotic states discovered experimentally always proceed via the strong and electromagnetic interactions. Recently, a tetraquark state with the quark content $bc\bar{q}\bar{q}$ was predicted by Lattice QCD simulations. It is below the mass threshold of $D\bar{B}$, which can only decay via the weak interaction. In this work, based on the decay mechanism of $T_{cc}$ as a $D{D}^{\ast }$ molecule, we propose that the decays of the $bc\bar{q}\bar{q}$ tertaquark state as a $D\bar{B}$ molecule proceed via the Cabibbo-favored weak decays of the $\bar{B}$ or $D$ meson, accompanied by the tree-level decay modes and the triangle decay modes. Our results indicate that the branching fraction of the $D\bar{B}$ molecule decaying into ${\pi }^{+}{K}^{-}{\bar{B}}^0$ is sizable, which is a good channel to observe the $D\bar{B}$ molecule in future experiments.

    hep-phPRD(2024)·2 citations
13. 13*

    Primordial monopoles, black holes and gravitational waves

    Ahmad Moursy🇪🇬 · Qaisar Shafi🇺🇸

    We show how topologically stable superheavy magnetic monopoles and primordial black holes can be generated at observable levels by the waterfall field in hybrid inflation models based on grand unified theories. In $SU(5)\times U(1{)}_{\chi }$ grand unification, the monopole mass is of order $4\times 10^{17}$ GeV, and it carries a single unit ($2\pi /e$) of Dirac magnetic charge as well as screened color magnetic charge. The monopole density is partially diluted to an observable value, and accompanied with the production of primordial black holes with mass of order $10^{17}$-$10^{19}$ g which may make up the entire dark matter in the universe. The tensor to scalar ratio $r$ is predicted to be of order $10^{-5}$ - $10^{-4}$ which should be testable in the next generation of CMB experiments such as CMB-S4 and LiteBIRD. The gravitational wave spectrum generated during the waterfall transition is also presented. The observed baryon asymmetry can be explained via leptogenesis.

    hep-phastro-ph.COJCAP(2024)·14 citations
14. 14*

    Constraining Millicharged dark matter with Gravitational positivity bounds

    Suro Kim🇰🇷 · Pyungwon Ko🇰🇷

    Gravitational positivity bounds provide consistency conditions for effective field theories with gravity. They turn out to be phenomenologically useful by providing lower bounds in parameters of new physics beyond the Standard Models (BSM). In this paper, we derive constraints on millicharged fermion dark matter models with massless dark photon using gravitational positivity bounds. Combining them with upper bounds from cosmological and astrophysical observations, we can severely constrain the parameter space of the model. In particular, we show that when the dark matter mass is lighter than the solar core temperature, most of the parameter region is excluded by combining gravitational positivity bounds and the stellar bounds.

    hep-phastro-ph.COhep-th5 citations
15. 15*

    Transition of dimuonium through foil

    Abdaljalel Alizzi🇷🇺 · Artem Uskov🇷🇺 · Zurab K. Silagadze🇷🇺

    This article presents a study of the passage of dimuonium through the foil of ordinary matter. First, we provide an overview of how dimuonium is planned to be produced for such a type of experiment and how it is expected to interact with the ordinary atoms -- predominantly electromagnetically via the screened coulomb potential of the atomic nuclei. Then, we describe the transport equations that represent the evolution of dimuonium states during the passage and their solution methods. Finally, for three different foils (Beryllium, Aluminium and Lead), we present the results of this study. To estimate impact of uncertainties in the potential of a target atom, we study 15 different approximations of the atomic potential and show that the corresponding atomic-potential-model-dependent error in the yields of the low lying states of dimuonium is quite small within the framework of the applied Born approximation. The convergence of the results after truncation of the infinite system of transport equations to the finite number of quantum states of dimuonium is also studied, and good convergence for the yields of low-lying states is demonstrated.

    hep-phphysics.atom-phPRA(2024)·1 citation
16. 16*

    Constraints on Bulk Fields: No-Go Conjectures for Braneworld Models

    G. Alencar🇧🇷 · M. Gogberashvili🇬🇪 · R. N. Costa Filho🇧🇷

    This work establishes a series of no-go conjectures that impose rigorous constraints on the localization of bulk fields in braneworld scenarios, specifically affecting gauge and spinor fields within five-dimensional spacetimes. Our approach differs from traditional methods as it does not rely on specific equations of motion, making our results broadly applicable across various braneworld models. These no-go conditions reveal fundamental limitations in field localization, challenging the feasibility of embedding fields on the brane. For instance, our analysis demonstrates that existing models fail to achieve consistent localization for gauge and spinor fields. Additionally, one of our conditions indicates that the effective Lagrangian on the brane cannot exhibit conformal invariance.

    hep-phgr-qchep-thEPJC(2025)·2 citations
17. 17*

    Relic Neutrino Background from Cosmic-Ray Reservoirs

    Andrea Giovanni De Marchi🇮🇹 · Alessandro Granelli🇮🇹 · Jacopo Nava🇮🇹 · Filippo Sala🇮🇹

    We compute the flux of relic neutrino background (R$\nu$B) up-scattered by ultra-high-energy (UHE) cosmic rays (CRs) in clusters that act as CR-reservoirs. The long trapping times of UHECRs make this flux larger than that of R$\nu$B up-scattered by UHECRs on their way to Earth, which we also compute. We find that IceCube excludes R$\nu$B weighted overdensities larger than $10^{10}$ in clusters, and that PUEO, RNO-G, GRAND and IceCube-Gen2 will test values down to $10^8$. Our treatment incorporates the momentum transfer dependence of the neutrino-nucleus cross section, deep inelastic scattering, a mixed UHECR composition, and flavour information on the up-scattered R$\nu$B fluxes for both cases of neutrino mass spectrum with normal and inverted ordering, providing new handles to possibly disentangle the up-scattered R$\nu$B from cosmogenic neutrinos.

    hep-phastro-ph.COastro-ph.HEPRD(2025)·19 citations
18. 18*

    Baryon-number -flavor separation in the topological expansion of QCD

    David Frenklakh🇺🇸 · Dmitri Kharzeev🇺🇸 · Giancarlo Rossi🇮🇹 · Gabriele Veneziano🇨🇭

    Gauge invariance of QCD dictates the presence of string junctions in the wave functions of baryons. In high-energy inclusive processes, these baryon junctions have been predicted to induce the separation of the flows of baryon number and flavor. In this paper we describe this phenomenon using the analog-gas model of multiparticle production proposed long time ago by Feynman and Wilson and adapted here to accommodate the topological expansion in QCD. In this framework, duality arguments suggest the existence of two degenerate junction-antijunction glueball Regge trajectories of opposite $\mathcal{C}$-parity with intercept close to 1/2. The corresponding results for the energy and rapidity dependence of baryon stopping are in reasonably good agreement with recent experimental findings from STAR and ALICE experiments. We show that accounting for correlations between the fragmenting strings further improves agreement with the data, and outline additional experimental tests of our picture at the existing (RHIC, LHC, JLab) and future (EIC) facilities.

    hep-phhep-thnucl-thJHEP(2024)·8 citations
19. 19*

    Top-down and bottom-up: Studying the SMEFT beyond leading order in $1/{\Lambda }^2$

    T. Corbett🇦🇹

    In order to assess the relevance of higher order terms in the Standard Model Effective Field Theory (SMEFT) expansion we consider four new physics models and their impact on the Drell Yan cross section. Of these four, one scalar model has no effect on Drell Yan, a model of fermions while appearing to generate a momentum expansion actually belongs to the vacuum expectation value expansion and so has a nominal effect on the process. The remaining two, a leptoquark and a Z' model exhibit a momentum expansion. After matching these models to dimension-ten we study how the inclusion of dimension-eight and dimension-ten operators in hypothetical effective field theory fits to the full ultraviolet models impacts fits. We do this both in the top-down approach, and in a very limited approximation to the bottom up approach of the SMEFT to infer the impact of a fully general fit to the SMEFT. We find that for the more weakly coupled models a strictly dimension-six fit is sufficient. In contrast when stronger interactions or lighter masses are considered the inclusion of dimension-eight operators becomes necessary. However, their Wilson coefficients perform the role of nuisance parameters with best fit values which can differ statistically from the theory prediction. In the most strongly coupled theories considered (which are already ruled out by data) the inclusion of dimension-ten operators allows for the measurement of dimension-eight operator coefficients consistent with theory predictions and the dimension-ten operator coefficients then behave as nuisance parameters. We also study the impact of the inclusion of partial next order results, such as dimension-six squared contributions, and find that in some cases they improve the convergence of the series while in others they hinder it.

    hep-phSciPost Phys.Core(2024)·7 citations
20. 20*

    Dissipative Dark Cosmology: From Early Matter Dominance to Delayed Compact Objects

    Joseph Bramante🇨🇦 · Christopher V. Cappiello🇨🇦 · Melissa D. Diamond🇨🇦 · J. Leo Kim🇨🇦 · Qinrui Liu🇨🇦 · Aaron C. Vincent🇨🇦

    We demonstrate a novel mechanism for producing dark compact objects and black holes through a dark sector, where all the dark matter can be dissipative. Heavy dark sector particles with masses above $10^4$ GeV can come to dominate the Universe and yield an early matter-dominated era before Big Bang Nucleosynthesis (BBN). Density perturbations in this epoch can grow and collapse into tiny dark matter halos, which cool via self interactions. The typical halo size is set by the Hubble length once perturbations begin growing, offering a straightforward prediction of the halo size and evolution depending on ones choice of dark matter model. Once these primordial halos have formed, a thermal phase transition can then shift the Universe back into radiation domination and standard cosmology. These halos can continue to collapse after BBN, resulting in the late-time formation of fragmented dark compact objects and sub-solar mass primordial black holes. We find that these compact objects can constitute a sizable fraction of all of dark matter. The resulting fragments can have masses between $10^{20}$ g to $10^{32}$ g, with radii ranging from $10^{-2}$ m to $10^5$ m, while the black holes can have masses between $10^8$ g to $10^{34}$ g. Furthermore, a unique feature of this model is the late-time formation of black holes which can evaporate today. We compare where these objects lie with respect to current primordial black hole and and massive (astrophysical) compact halo object constraints.

    hep-phastro-ph.COPRD(2024)·17 citations
21. 21*

    Assessing observational constraints on dark energy

    David Shlivko🇺🇸 · Paul Steinhardt🇺🇸

    Observational constraints on time-varying dark energy ({\it e.g.}, quintessence) are commonly presented on a $w_0$-$w_a$ plot that assumes the equation of state of dark energy strictly satisfies $w(z)=w_0+w_{a}z/(1+z)$ as a function of the redshift $z$. Recent observations favor a sector of the $w_0$-$w_a$ plane in which $w_0>-1$ and $w_0+w_a<-1$, suggesting that the equation of state underwent a transition from violating the null energy condition (NEC) at large $z$ to obeying it at small $z$. In this paper, we demonstrate that this impression is misleading by showing that simple quintessence models satisfying the NEC for all $z$ predict an observational preference for the same sector. We also find that quintessence models that best fit observational data can predict a value for the dark energy equation of state at present that is significantly different from the best-fit value of $w_0$ obtained assuming the parameterization above. In addition, the analysis reveals an approximate degeneracy of the $w_0$-$w_a$ parameterization that explains the eccentricity and orientation of the likelihood contours presented in recent observational studies.

    ↳ astro-ph.COgr-qchep-phhep-thPLB(2024)·200 citations
22. 22*

    Key drivers of the preference for dynamic dark energy

    Zhiqi Huang🇨🇳 · Jianqi Liu🇨🇳 · Jianfeng Mo🇨🇳 · Yan Su🇨🇳 · Junchao Wang🇨🇳 · Yanhong Yao🇨🇳 · Guangyao Yu🇨🇳 · Zhengxin Zhu🇨🇳 · Zhuoyang Li🇨🇳 · Zhenjie Liu🇨🇳 · Haitao Miao🇨🇳 · Hui Tong🇦🇺

    Joint analysis of the baryon acoustic oscillations (BAO) measurement by the Dark Energy Spectroscopic Instrument (DESI) first data release, Type Ia supernovae (SNe) of the Dark Energy Survey Year 5 (DES5YR) release and cosmic microwave background (CMB) data favors a quintom-like dynamic dark energy model over the standard Lambda cold dark matter ($\Lambda$CDM) model at $3.9\sigma$ level (Adame et al. 2024). We confirm the previous finding in the literature that the preference for dynamic dark energy does not rely on the detailed modeling of CMB physics and remains at a similar significance level ($3.2\sigma$) when the full CMB likelihood is replaced by a CMB acoustic-oscillation angle (${\theta }_{\star }$) prior and a baryon abundance (${\Omega }_b{h}^2$) prior. The computationally efficient ${\theta }_{\star }$ and ${\Omega }_b{h}^2$ priors allow us to take a frequentist approach by comparing DES5YR SNe and DESI BAO with a large number ($\gtrsim 10^4$) of Planck-constrained $\Lambda$CDM simulations. We find that $\ge 3.2\sigma$ preference for dynamic dark energy is very rare (occurrence rate = $0.28\%$) in simulations. When we combine DESI BAO with SN simulations or combine DES5YR SNe with BAO simulations, the occurrence rate of $\ge 3.2\sigma$ preference for dynamic dark energy increases to $1.2\%$ and $4.8\%$, respectively. These results indicate an internal inconsistency, i.e., a significant tension between DESI BAO + DES5YR SNe and Planck-constrained $\Lambda$CDM models in both Bayesian and frequentist points of view. Although both DESI BAO and DES5YR SNe contribute to the preference for dynamic dark energy, the contribution from DES5YR SNe is more significant. In the frequentist point of view, even DES5YR SNe alone is in tension with Planck-constrained $\Lambda$CDM models, though in Bayesian point of view this tension is prior dependent and inconclusive.

    ↳ astro-ph.COhep-phhep-thPRD(2024)·29 citations
23. 23*

    $1/N$ Corrections in ${\text{QCD}}_2$: Small Mass Limit and Threshold States

    Ilia V. Kochergin🇺🇸

    In this paper we investigate $1/N$ corrections to mesonic spectrum in $1+1$-dimensional Quantum Chromodynamics (${\text{QCD}}_2$) with fundamental quarks using effective Hamiltonian method. We express the corrections in terms of 't Hooft equation solutions. First, we consider 2-flavor model with a heavy and a light quark. We show that, in contrast to some claims in earlier literature, the $1/N$ correction to the mass of the heavy-light meson remains finite when the light quark mass is taken to zero. Nevertheless, the corrections become significantly larger in this limit; we attribute this to the presence of massless modes in the spectrum. We also study the corrections to the lightest meson mass in 1-flavor model and show that they are consistent with recent numerical data, but not with the prediction coming from bosonization. Then we study low energy effective theory for 2 flavors. We show that the 3-meson interaction vertex correctly reproduces Wess-Zumino-Witten (WZW) coupling when both quarks become massless. This coupling does not change even if one of the quarks is massive. We employ Discretized Light Cone Quatization (DLCQ) to check the continuum results and show that the improved version can be used for small quark mass. Finally, we study the states associated with $1\to 2$ meson thresholds. Using degenerate perturbation theory, we show that when the decay is allowed by parity, the infinite $N$ theory has near-threshold bound states that mix one- and two-meson parts. They are $1/3$ two-meson and $2/3$ one-meson and the corrections to their masses have unusual scaling $\sim 1/N^{2/3}$.

    ↳ hep-thhep-phJHEP(2025)·7 citations
24. 24*

    On the Detection and Characterization of Quasiperiodic Oscillations in Astronomical Time Series: Gamma-Ray Burst X-Ray Light Curves as a Test Case

    Fei-Fan Song · Jirong Mao🇨🇳

    The study of temporal properties of variable sources can elucidate their physical processes. In this context, we present a critical study comparing three approaches to periodic or quasiperiodic behavior: Gaussian process, power spectrum, and wavelet analysis, using celerite, Lomb-Scargle periodograms, and weighted wavelet-Z transforms, respectively. We use 15 Swift-X-ray Telescope light curves of short gamma-ray bursts (sGRBs) as examples. A comprehensive analysis of two sGRB X-ray light curves is performed. The results reveal the importance of artifacts, largely in the form of false quasiperiodic oscillation signals, possibly introduced by preprocessing (such as detrending) or other aspects of the analysis. The exploration described in this paper can be helpful for future studies of variability in GRBs, active galactic nuclei, and other astronomical sources.

    ↳ astro-ph.HEhep-phApJ(2024)·3 citations
25. 25*

    Baryonic screening masses in QCD at high temperature

    L. Giusti🇮🇹 · T. Harris🇨🇭 · D. Laudicina🇮🇹 · M. Pepe🇮🇹 · P. Rescigno🇮🇹

    We compute the baryonic screening masses with nucleon quantum numbers and its negative parity partner in thermal QCD with $N_f=3$ massless quarks for a wide range of temperatures, from $T\sim 1$ GeV up to $\sim 160$ GeV. The computation is performed by Monte Carlo simulations of lattice QCD with $O(a)$-improved Wilson fermions by exploiting a recently proposed strategy to study non-perturbatively QCD at very high temperature. Very large spatial extensions are considered in order to have negligible finite volume effects. For each temperature we have simulated $3$ or $4$ values of the lattice spacing, so as to perform the continuum limit extrapolation with confidence at a few permille accuracy. The degeneracy of the positive and negative parity-state screening masses, expected from Ward identities associated to non-singlet axial transformations, provides further evidence for the restoration of chiral symmetry in the high temperature regime of QCD. In the entire range of temperatures explored, the baryonic masses deviate from the free theory result, $3\pi T$, by $4$-$8\%$. The contribution due to the interactions is clearly visible up to the highest temperature considered, and cannot be explained by the expected leading behavior in the QCD coupling constant $g$ over the entire range of temperatures explored.

    ↳ hep-lathep-phPLB(2024)·18 citations
26. 26*

    Cross-platform hardware benchmark of style-based quantum GANs for data augmentation on superconducting and trapped-ion processors

    Julien Baglio

    In the noisy intermediate-scale quantum era, controlled benchmarks of quantum machine-learning workloads across hardware modalities are needed to quantify how given algorithms behave under native provider execution stacks. This work presents such a benchmark for the style-based quantum generative adversarial network (qGAN) on a high-energy physics data-augmentation task. We compare two commercially available gate-model quantum computers: the IBM ibm_torino hardware, based on superconducting transmon qubits from the Heron chip and the IonQ aria-1 hardware, based on trapped-ion qubits. The generator architecture and trained parameters are kept fixed, and built-in mitigation is disabled when possible. We report quality and runtime metrics under each provider's native stack. The workflow uses circuit replication across available qubits, up to 48 on IBM and 24 on IonQ, to reduce the number of submitted jobs required for the target sample set. To our knowledge, this is one of the first controlled style-based qGAN hardware-to-hardware comparisons for this data-augmentation task. We observe that both platforms complete the task successfully, with marginal Kullback-Leibler divergences somewhat lower on aria-1, while end-to-end runtime is significantly shorter on ibm_torino. These results are an application-specific tradeoff benchmark, not a claim of algorithmic novelty.

    ↳ quant-phhep-phAIP Adv.(2026)·12 citations
27. 27*

    Generalized parton distributions from the pseudo-distribution approach on the lattice

    Shohini Bhattacharya🇺🇸 · Krzysztof Cichy🇵🇱 · Martha Constantinou🇺🇸 · Andreas Metz🇺🇸 · Niilo Nurminen🇵🇱 · Fernanda Steffens🇩🇪

    Generalized parton distributions (GPDs) are key quantities for the description of a hadron's three-dimensional structure. They are the current focus of all areas of hadronic physics -- phenomenological, experimental, and theoretical, including lattice QCD. Synergies between these areas are desirable and essential to achieve precise quantification and understanding of the structure of, particularly nucleons, as the basic ingredients of matter. In this paper, we investigate, for the first time, the numerical implementation of the pseudo-distribution approach for the extraction of zero-skewness GPDs for unpolarized quarks. Pseudo-distributions are Euclidean parton correlators computable in lattice QCD that can be perturbatively matched to the light-cone parton distributions of interest. Being closely related to the quasi-distributions and coming from the same lattice-extracted matrix elements, they are, however, subject to different systematic effects. We use the data previously utilized for quasi-GPDs and extend it with other momentum transfers and nucleon boosts, in particular a higher one ($P_3=1.67$ GeV) with eight-fold larger statistics than the largest one used for quasi-distributions ($P_3=1.25$ GeV). We renormalize the matrix elements with a ratio scheme and match the resulting Ioffe time distributions to the light cone in coordinate space. The matched distributions are then used to reconstruct the $x$-dependence with a fitting ansatz.We investigate some systematic effects related to this procedure, and we also compare the results with the ones obtained in the framework of quasi-GPDs. Our final results involve the invariant four-momentum transfer squared ($-t$) dependence of the flavor non-singlet ($u-d$) $H$ and $E$ GPDs.

    ↳ hep-lathep-phPRD(2024)·29 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.