Thu·Dec 12, 2024Thursday·December 12, 2024

1. 01*

   Melting of $c\bar{c}$ and $b\bar{b}$ pairs in the pre-equilibrium stage of proton-nucleus collisions at the Large Hadron Collider

   Lucia Oliva🇮🇹 · Gabriele Parisi🇮🇹 · Vincenzo Greco🇮🇹 · Marco Ruggieri🇮🇹

   We study the melting of $c\bar{c}$ and $b\bar{b}$ pairs in the early stage of high-energy proton-nucleus collisions. We describe the early stage in terms of an evolving $SU(3)$ glasma stage, that is dominated by intense, out-of-equilibrium gluon fields. On top of these fields, we liberate heavy quark-antiquark pairs, whose constituents are let evolve according to relativistic kinetic theory coupled to the gluon fields. We define a pair-by-pair probability that the pair melts during the evolution, which we relate to the fluctuations of the color charges induced by the interaction of the quarks with the gluon fields. We find that color decorrelation is the main melting mechanism within the pre-equilibrium stage. Moreover, we estimate that within $\Delta \tau \approx 0.4-0.5$ fm/c after the formation time of the pairs, about $50\%$ of $c\bar{c}$ and $b\bar{b}$ pairs are melted.

   hep-phnucl-thPRD(2025)·12 citations
2. 02*

   On radiative corrections to lepton number violating processes

   Takehiko Asaka🇯🇵 · Hiroyuki Ishida🇯🇵 · Kazuki Tanaka🇯🇵

   We consider the minimal model of the seesaw mechanism by introducing two right-handed neutrinos, whose masses are comparable to the electroweak scale. This framework is attractive, since it is testable at terrestrial experiments. A critical consequence of this mechanism is the violation of lepton number conservation due to the Majorana masses of both active neutrinos and heavy neutral leptons. In particular, we investigate the impact of the radiative corrections to Majorana masses of left-handed neutrinos on the lepton number violating processes, such as the neutrinoless double beta decay: $(Z,A)\to (Z+2,A)+2e^{-}$ and the inverse neutrinoless double beta decay: $e^{-}{e}^{-}\to W^{-}{W}^{-}$. It is shown that the cross section of the inverse neutrinoless double beta decay can increase by $\mathcal{O}(10)$~% when the masses of heavy neutral leptons are $\mathcal{O}(1)$~TeV, which has significant implications on future experiments.

   hep-phPTEP(2025)·0 citations
3. 03*

   Production of doubly charmed tetraquark $T_{cc}$ via photon-photon fusion at electron-positron colliders

   Jun Jiang🇨🇳 · Shi-Yuan Li🇨🇳 · Xiao Liang🇨🇳 · Yan-Rui Liu🇨🇳 · Zong-Guo Si🇨🇳 · Zhong-Juan Yang🇨🇳

   Within a phenomenological diquark fragmentation model, we study the production of doubly charmed tetraquark $T_{cc}$ via photon-photon fusion at electron-positron colliders. The production of $T_{cc}$ is divided into two steps: the perturbative production of heavy $(cc)$-diquark and its nonperturbative hadronization. Two diquark configurations of $(cc){[}^3{S}_1{]}_{\bar{3}}$ and $(cc){[}^1{S}_0{]}_6$ are considered, and the $(cc){[}^3{S}_1{]}_{\bar{3}}$ state dominates the produciotn of $T_{cc}$. We discuss two hadronization models of $(cc){[}^3{S}_1{]}_{\bar{3}}$ intermediate state into the tetraquark $T_{cc}$. It is found that it is promising to observe the tetraquark $T_{cc}$ via photon-photon fusion process both at the Circular Electron Positron Collider (CEPC) and the International Linear Collider (ILC). We find that the cross sections are sensitive to constituent charm quark mass of diquark, and they also have strong dependence on the hadronization models.

   hep-phPLB(2025)·6 citations
4. 04*

   An analysis of the longitudinal structure function at next-to-leading order approximation at small-$x$

   G.R.Boroun🇮🇷 · Yanbing Cai🇨🇳

   The longitudinal structure function is considered at the next-to-leading order approximation using the expansion method, as defined by M.B.Gay Ducati and P.B.Goncalves [Phys.Lett.B {\bf390}, 401 (1997)] and further developed by Jingxuan Chen et al., [Chin.Phys.C {\bf48}, 063104 (2024)]. This method provides results for a wide range of $x$ and $Q^2$ values. It is observed that the behavior of the longitudinal structure function depends on the fractional momentum carried by gluons at low $x$. The extracted longitudinal structure functions $F_L(x,Q^2)$ are in line with data from the H1 Collaboration [V. Andreev et al. (H1 Collaboration), Eur. Phys. J. C 74, 2814 (2014)] and the CT18 parametrization method [T.-J. Hou et al., Phys. Rev. D 103, 014013 (2021)].

   hep-phCPC(2025)·3 citations
5. 05*

   Unveiling the Invisible: ALPs and Sterile Neutrinos at the LHC and HL-LHC

   Kingman Cheung🇹🇼 · C.J. Ouseph🇰🇷 · Sin Kyu Kang🇰🇷

   We investigate the potential of using the signature of mono-Higgs plus large missing energies to constrain on two new physics models, namely the model of an axion-like particle (ALP) and the model of sterile neutrinos. We focus on the Higgs-ALP interactions starting at dimension-six and the Higgs-sterile neutrino interactions starting at dimension-five, via the processes $pp\to haa$ for ALP production and $pp\to hNN$ for sterile neutrinos at the LHC and High Luminosity LHC (HL-LHC), followed by the Higgs decay $h\to b\bar{b}$. We establish bounds on the ALP-Higgs coupling $\frac{C_{aH}}{{\Lambda }^2}$ and sterile neutrino-Higgs coupling $\frac{{\lambda }_3}{M_{\ast }}$, respectively, for ALP and sterile-neutrino mass ranging from 1 to 60 GeV, using the recent ATLAS data on mono-Higgs plus missing energies at the LHC $(\sqrt{s}=13\mathrm{TeV}\mathrm{and}\mathcal{L}=139{\mathrm{fb}}^{-1})$. The most stringent constraint occurs in the missing transverse energy $M_{ET}$ range $200<M_{ET}\le 350$ GeV. We also estimate the sensitivities that we can achieve at the HL-LHC ($\sqrt{s}=14$ TeV and $\mathcal{L}=3000$ fb${}^{-1}$). We obtain improved sensitivities across various missing energy regions. The ALP model exhibits better sensitivities, particularly at lower mass range, compared to the sterile neutrino model, which shows weaker sensitivities across similar mass and energy ranges. Our results underscore the potential of the mono-Higgs signature as a robust probe for physics beyond the Standard Model.

   hep-phhep-exJHEP(2025)·1 citation
6. 06*

   Constraining the SMEFT at Present and Future Colliders

   Eugenia Celada🇬🇧

   We present results from SMEFiT3.0, a global SMEFT fit of Higgs, top quark, and diboson production data from the LHC. Our updated analysis includes recent inclusive and differential measurements from the LHC Run II, together with the exact implementation of electroweak precision observables (EWPOs) from LEP and SLD. We then analyse the impact of HL-LHC measurements by adding to SMEFiT3.0 the projections obtained by extrapolating from Run II data. Finally we estimate the potential of two proposed high-energy circular $e^{+}{e}^{-}$ colliders, the FCC-ee and the CEPC, in further improving the bounds on the SMEFT parameters.

   hep-phSciPost Phys.Proc.(2026)·2 citations
7. 07*

   Spectral properties of pseudo-scalar mesons through the QCD chiral crossover

   Peter Lowdon🇩🇪 · Owe Philipsen🇩🇪

   We summarise recent progress towards the non-perturbative determination of thermal spectral functions for pseudo-scalar mesons in QCD by exploiting constraints imposed by micro-causality at finite temperature. For temperatures not much above the vacuum particle mass, continuous contributions from scattering, Landau damping and collective excitations are found to be negligible. This allows for a quantitative description of spatial and temporal lattice correlators in terms of thermoparticles, i.e.~vacuum excitations modified by medium effects, with resonance-like structures persisting for a range above the chiral crossover.

   hep-phhep-latJ.Subatomic Part.Cosmol.(2025)·1 citation
8. 08*

   Probing Lorentz violating effects on the exclusive $e^{+}{e}^{-}$ production in ultraperipheral heavy-ion collisions

   Laura Duarte🇧🇷 · Victor P. Goncalves🇧🇷 · Daniel E. Martins🇵🇱

   The impact of Lorentz violating (LV) terms on the exclusive $e^{+}{e}^{-}$ production in ultraperipheral heavy-ion collisions at the Large Hadron Collider (LHC) is investigated, considering vectorial and axial couplings. Results for the differential and total cross-sections are presented, and the sensitivity to a time-like coupling is estimated. Our results indicate that this process can improve the current upper bounds on the LV terms.

   hep-phhep-exPRD(2025)·1 citation
9. 09*

   Quark TMDs from back-to-back dijet production at forward rapidities in pA collisions beyond eikonal accuracy in the CGC

   Tolga Altinoluk🇵🇱 · Guillaume Beuf🇵🇱 · Etienne Blanco🇵🇱 · Swaleha Mulani🇵🇱

   We study dijet production in pA collisions at forward rapidities at next-to-eikonal accuracy. We restrict ourselves to the next-to-eikonal corrections that are induced by the quark background field of the target. We consider all possible channels, compute scattering amplitudes both in general kinematics and in the back-to-back limit. By using these results, we compute the back-to-back production cross section and obtain a factorized expression with a quark TMD times associated hard factor for each channel.

   hep-phJHEP(2025)·17 citations
10. 10*

    Phenomenology of the standard HVM and 95.4 GeV excess

    Gauhar Abbas🇮🇳 · Neelam Singh🇮🇳

    We investigate the collider phenomenology of the standard Hierarchical VEVs Model by proposing a new version, which avoids large flavor changing neutral current interactions, thus, rendering the scale of new physics as low as the electroweak scale. The resulting collider signatures are distinctive and testable at the High-Luminosity LHC, the High-Energy LHC, and future 100\,TeV hadron colliders. Remarkably, one of the pseudoscalars in the model can account for the 95.4\,GeV di-photon excess observed by ATLAS and CMS. In addition, the model naturally accommodates a new class of neutrino-philic dark matter candidate, \emph{neutrinic dark matter}, that interacts exclusively with neutrino pairs.

    hep-phEur.Phys.J.Plus(2026)·8 citations
11. 11*

    Phenomenology of Neutrino-Dark Matter Interaction in DSNB and AGN

    Po-Yan Tseng🇹🇼 · Yu-Min Yeh🇹🇼

    We investigate a neutrino-scalar dark matter (DM) $\nu \varphi$ interaction encountering distinctive neutrino sources, namely Diffuse Supernova Neutrino Background (DSNB) and Active Galactic Nuclei (AGN). The interaction is mediated by a fermionic particle $F$, in which the $\nu \varphi$ scattering cross section characterizes different energy dependent with respect to the kinematic regions, and manifests itself through the attenuation of neutrino fluxes from these sources. We model the unscattered neutrino flux from DSNB via core-collapse supernova (CCSN) and star-formation rate (SFR), then incorporate the present Super-Kamionkande and future DUNE/Hyper-Kamiokande experiments to set limits on DM-neutrino interaction. For AGNs, NGC 1068 and TXS 0506+056, where the neutrino carries energy above TeV, we select the kinematic region $m_F^2\gg E_{\nu }{m}_{\varphi }\gg m_{\varphi }^2$ such that the $\nu \varphi$ scattering cross section features an enhancement at high energy. Furthermore, taking into account the DM spike profile at the center of AGN, we constrain on $m_{\varphi }$ and scattering cross section via computing the neutrino flux at IceCube, where the $\varphi {\varphi }^{\ast }$ annihilation cross section is implemented to determine the saturation density of the spikes. Notice that the later results heavily rely on the existence of DM spike at the center of AGN, otherwise, our results may alter.

    hep-phJCAP(2025)·6 citations
12. 12*

    Impact-parameter-dependent solutions to the Balitsky-Kovchegov equation at next-to-leading order

    J. Cepila🇨🇿 · J. G. Contreras🇨🇿 · M. Matas🇨🇿 · M. Vaculciak🇨🇿

    A stable numerical solution of the impact-parameter-dependent next-to-leading order Balitsky-Kovchegov equation is presented for the first time. The rapidity evolution of the dipole amplitude is discussed in detail. Dipole amplitude properties, such as the evolution speed or anomalous dimension behaviour, are studied as a function of the impact parameter and the dipole size and compared to solutions of the impact-parameter-dependent leading-order Balitsky-Kovchegov equation with the collinearly improved kernel. The next-to-leading evolution also strongly suppresses the Coulomb tails compared to the collinearly improved and leading order solutions.

    hep-phPRD(2025)·7 citations
13. 13*

    Revisiting light-flavor diquarks in the inverse matrix method of QCD sum rules

    Halil Mutuk🇹🇷

    This study reexamines the spectroscopic parameters of light-flavor diquarks within the framework of quantum chromodynamics sum rules (QCDSR) using the inverse matrix method. Conventional QCDSR analyses are based on assumptions such as quark-hadron duality and continuum models, which introduce a degree of systematic uncertainty. The inverse matrix method circumvents these assumptions by reformulating the problem as an inverse integral equation and expanding the unknown spectral density using orthogonal Laguerre polynomials. This method allows for a direct determination of spectral densities, thereby enhancing the precision of predictions regarding resonance masses and decay constants. By employing this methodology with regard to light-flavor diquarks ($sq$ and $ud$), it is possible to extract the associated masses and decay constants. The results indicate that the masses of diquarks with quantum numbers $J^P=0^{+}$ and $J^P=0^{-}$ are nearly degenerate. We compare our results regarding masses and decay constants with those of other theoretical predictions, which could prove a useful complementary tool in interpretation. Our results are consistent with those in the literature and can be shown as evidence for the consistency of the method. The results achieved in this study highlight the potential of the inverse matrix method as a robust tool for exploring nonperturbative QCD phenomena and elucidating the internal structure of exotic hadronic systems.

    hep-phhep-exhep-latPRD(2025)·4 citations
14. 14*

    An Improved Precision Calculation of the $0\nu \beta \beta$ Contact Term within Chiral Effective Field Theory

    Graham Van Goffrier🇬🇧

    Neutrinoless double-beta ($0\nu \beta \beta$) decay is an as-yet unobserved nuclear process, which stands to provide crucial insights for model-building beyond the Standard Model of particle physics. Its detection would simultaneously confirm the hypothesis that neutrinos are Majorana fermions, thus violating lepton-number conservation, and provide the first measurement of the absolute neutrino mass scale. This work aims to improve the estimation within chiral effective field theory of the so-called ''contact term'' for $0\nu \beta \beta$-decay, a short-range two-nucleon effect which is unaccounted for in traditional nuclear approaches to the process. We conduct a thorough review of the justifications for this contact term and the most precise computation of its size to date ($g_{\nu }^{NN}$ = 1.3(6) at renormalisation point $\mu =m_{\pi }$), whose precision is limited by a truncation to elastic intermediate hadronic states. We then perform an extension of this analysis to a subleading class of inelastic intermediate states which we characterise, delivering an updated figure for the contact coefficient ($g_{\nu }^{NN}$ = 1.4(3) at $\mu =m_{\pi }$) with uncertainty reduced by half. Such ab initio nuclear results, especially with enhanced precision, show promise for the resolution of disagreements between estimates of $0\nu \beta \beta$ from different many-body methods.

    hep-phnucl-thPRD(2025)·7 citations
15. 15*

    Jet substructure of light and heavy flavor jets at RHIC

    Zhuoheng Yang🇺🇸 · Oleh Fedkevych🇺🇸 · Roli Esha🇺🇸

    Jet substructure studies at the Large Hadron Collider have been used to constrain parton distribution functions, test perturbative QCD, measure the strong-coupling constant, and probe the properties of the quark-gluon plasma. We extend these studies to lower energies at the Relativistic Heavy Ion Collider that would additionally allow us to test existing models of non-perturbative physics. In this study, we present a PYTHIA8-based Monte Carlo study of substructure of jets produced in $p+p$ collisions at 200 GeV. The selection criteria is adapted for a feasible measurement at sPHENIX. We consider different types of jet substructure observables such as jet angularities and primary Lund Plane with a special focus on suppression of collinear radiation around emitting heavy quark known as a dead cone effect.

    hep-phnucl-exnucl-thPRC(2026)·1 citation
16. 16*

    Axion mass prediction from adaptive mesh refinement cosmological lattice simulations

    Joshua N. Benabou🇺🇸 · Malte Buschmann🇳🇱 · Joshua W. Foster🇺🇸 · Benjamin R. Safdi🇺🇸

    The quantum chromodynamics (QCD) axion arises as the pseudo-Goldstone mode of a spontaneously broken abelian Peccei-Quinn (PQ) symmetry. If the scale of PQ symmetry breaking occurs below the inflationary reheat temperature and the domain wall number is unity, then there is a unique axion mass that gives the observed dark matter (DM) abundance. Computing this mass has been the subject of intensive numerical simulations for decades since the mass prediction informs laboratory experiments. Axion strings develop below the PQ symmetry-breaking temperature, and as the string network evolves it emits axions that go on to become the DM. A key ingredient in the axion mass prediction is the spectral index of axion radiation emitted by the axion strings. We compute this index in this work using the most precise and accurate large-scale simulations to date of the axion-string network leveraging adaptive mesh refinement to achieve the precision that would otherwise require a static lattice with 262,144${}^3$ lattice sites. We find a scale-invariant axion radiation spectrum to within 1% precision. Accounting for axion production from strings prior to the QCD phase transition leads us to predict that the axion mass should be approximately $m_a\in (45,65)$ $\mu \mathrm{eV}$. However, we provide preliminary evidence that axions are produced in greater quantities from the string-domain-wall network collapse during the QCD phase transition, potentially increasing the mass prediction to as much as 300 $\mu$eV.

    hep-phastro-ph.COhep-thPRL(2025)·77 citations
17. 17*

    Effective Field Theory and Scalar Triplet Dark Matter

    Carolina Arbeláez🇨🇱 · Marcela González🇨🇱 · Martin Hirsch🇪🇸 · Nicolás A. Neill🇨🇱 · Diego Restrepo🇨🇴

    We discuss an extension of the standard model with a real scalar triplet, $T$, including non-renormalizable operators (NROs) up to $d=6$. If $T$ is odd under a $Z_2$ symmetry, the neutral component of $T$ is a good candidate for the dark matter (DM) of the universe. We calculate the relic density and constraints from direct and indirect detection on such a setup, concentrating on the differences with respect to the simple model for a DM $T$ with only renormalizable interactions. Bosonic operators can change the relic density of the triplet drastically, opening up new parameter space for the model. Indirect detection constraints, on the other hand, rule out an interesting part of the allowed parameter space already today and future CTA data will, very likely, provide a decisive test for this setup.

    hep-phJHEP(2025)·0 citations
18. 18*

    Off-shell vertices in heavy particle effective theories and $B\to D\pi \ell \nu$

    Michele Papucci🇺🇸 · Ryan Plestid🇺🇸

    We study the modifications to decay amplitudes in heavy to heavy semileptonic decays with multiple hadrons in the final state due to intermediate heavy hadrons being off-shell or having a finite width. Combining Heavy Hadron Chiral Perturbation Theory (HH$\chi$PT) with a BCFW on-shell factorization formula, we show that these effects induce $O(1/M)$ corrections to the standard results computed in the narrow-width approximation and therefore are important in extracting form factors from data. A combination of perturbative unitarity, analyticity, and reparameterization invariance fully determine these corrections in terms of known Isgur-Wise functions without the need to introduce new form factors. In doing so, we develop a novel technique to compute the boundary term at complex infinity in the BCFW formula for theories with derivatively coupled scalars. While we have used the $\bar{B}\to D\pi \ell \nu$ decay as an example, these techniques can generally be applied to effective field theories with (multiple) distinct reference vectors.

    hep-phnucl-thJHEP(2025)·2 citations
19. 19*

    New Technologies for Axion and Dark Photon Searches

    Asher Berlin🇺🇸 · Yonatan Kahn🇺🇸

    The search for dark matter and physics beyond the Standard Model has grown to encompass a highly interdisciplinary approach. In this review, we survey recent searches for light, weakly-coupled particles - axions and dark photons - over the past decade, focusing on new experimental results and the incorporation of technologies and techniques from fields as diverse as quantum science, microwave engineering, precision magnetometry, and condensed matter physics. We also review theoretical progress which has been useful in identifying new experimental directions, and identify the areas of most rapid experimental progress and the technological advances required to continue exploring the parameter space for axions and dark photons.

    hep-phhep-exAnn.Rev.Nucl.Part.Sci.(2025)·21 citations
20. 20*

    Constraining non-standard neutrino interactions with neutral current events at long-baseline oscillation experiments

    Julia Gehrlein🇺🇸 · Pedro A. N. Machado🇺🇸 · João Paulo Pinheiro🇪🇸

    We explore, for the first time, {\textit{neutral-current}} events at long-baseline experiments to constrain vector and axial-vector neutrino non-standard interactions (NSI) with quarks. We leverage the flavor dependence of NSIs to perform an oscillation analysis in the neutral-current channel. We first introduce a framework to parametrize the effect of NSI on the cross section. Then, as an example, we analyze NOvA neutral-current data which provides significantly improved constraints on the axial-vector NSI parameters ${\epsilon }_{\mu \mu }^A,{\epsilon }_{\tau \tau }^A$ and ${\epsilon }_{e\mu }^A$. This is highly complementary to constraints from SNO data, which, differently from long-baseline neutral current data, is not sensitive to isospin conserving NSIs ${\epsilon }_u^A={\epsilon }_d^A$. Additionally, we disfavor large values of the diagonal vectorial NSI ${\epsilon }_{\mu \mu }^V$ and \varepsilon_{\tau\tau}^V$ which originate from the LMA-Dark solution. We also highlight the complementarity between NSI searches at oscillation experiments using charged current and neutral current channels.

    hep-phhep-exJHEP(2025)·10 citations
21. 21*

    Electroweak spin-1 resonances in Composite Higgs models

    Rosy Caliri · Jan Hadlik · Manuel Kunkel · Werner Porod · Christian Verollet

    Composite Higgs models predict the existence of various bound states. Among these are spin-1 resonances. We investigate models containing ${\text{SU(2)}}_L\times {\text{SU(2)}}_R$ as part of the unbroken subgroup in the new strong sector. These models predict that there are two neutral and one charged spin-1 resonances mixing sizably with the SM vector bosons. As a consequence, these can be singly produced in Drell-Yan processes at the LHC. We explore their rich LHC phenomenology and show that there are still viable scenarios consistent with existing LHC data where the masses of these states can be as low as about 1.5 TeV.

    hep-phhep-exJHEP(2025)·7 citations
22. 22*

    Angular Distribution of Gamma Rays Produced in Proton-Proton Collisions

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

    Accurate modeling of how high-energy proton-proton collisions produce gamma rays through the decays of pions and other secondaries is needed to correctly interpret astrophysical observations with the Fermi-LAT telescope. In the existing literature on cosmic-ray collisions with gas, the focus is on the gamma-ray yield spectrum, $d{N}_{\gamma }/dE$. However, in some situations, the joint energy and angular distribution can be observed, so one needs instead $d^2{N}_{\gamma }/dEd\Omega$. We provide calculations of this distribution over the energy range from the pion production threshold to $100\mathrm{GeV}$, basing our results on FLUKA simulations. We provide the results in tabular form and provide a Python tool on GitHub to aid in utilization. We also provide an approximate analytic formula that illuminates the underlying physics. We discuss simplified examples where this angular dependence can be observed to illustrate the necessity of taking the joint distribution into account.

    hep-phastro-ph.HEPRD(2025)·5 citations
23. 23*

    Probing Millicharged Particles at an Electron Beam Dump with Ultralow-Threshold Sensors

    Rouven Essig🇺🇸 · Peiran Li🇺🇸 · Zhen Liu🇺🇸 · Megan McDuffie🇺🇸 · Ryan Plestid🇺🇸 · Hailin Xu🇺🇸

    We propose to search for millicharged particles produced in high-intensity electron beam dumps using small ultralow-threshold sensors. As a concrete example, we consider a Skipper-CCD placed behind the beam dump in Hall A at Jefferson Lab. We compute the millicharged particle flux, including both electromagnetic cascade and meson productions emanating from an aluminum target. We find that the sensitivity of a modest 2x14 array of Skipper-CCDs can exceed the sensitivity of all existing searches for millicharged particle masses below 1.5 GeV, and is either competitive or world leading when compared to other proposed experiments. Our results demonstrate that small-scale ultralow threshold silicon devices can enhance the reach of accelerator-based experiments, while fitting comfortably within existing experimental halls.

    hep-phhep-exJHEP(2025)·13 citations
24. 24*

    Confronting impact-parameter dependent model in next-to-leading order of perturbative QCD with combined HERA data

    José Garrido🇨🇱 · Michael Roa🇨🇱 · Miguel Guevara🇨🇱

    In this talk, we present the CGC/saturation approach of Ref.[C.~Contreras, E.~Levin, R.~Meneses and M.~Sanhueza,Eur. Phys. J. C 80 (2020) no.11, 1029] and its parameters determined from the combined HERA data. This model features an analytical solution for the non-linear Balitsky-Kovchegov (BK) evolution equation and the exponential behavior of the saturation momentum on the impact parameter $b$-dependence, characterized by $Q_s\propto \exp (-mb)$. We compare our results with experimental data at small-$x$, including the proton structure function $F_2$, charm structure function $F_2^{c\bar{c}}$, and exclusive vector meson production. The model shows good agreement across a wide kinematic range. Our findings support using this approach for reliable predictions in upcoming experiments like the Electron-Ion Collider (EIC) and the LHeC.

    hep-ph0 citations
25. 25*

    Did IceCube discover Dark Matter around Blazars?

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

    Models of blazar jets, that explain observations of their photon spectra, typically predict too few neutrinos to be possibly seen by existing telescopes. In particular, they fall short in reproducing the first neutrino ever detected from a blazar, TXS 0506+056, by IceCube in 2017. We predict larger neutrino fluxes by using the same jet models, extended to include deep inelastic scatterings between protons within the jets and sub-GeV dark matter (DM) around the central black holes of blazars. In this way we succeed in explaining neutrino observations of TXS 0506+056, for DM parameters allowed by all laboratory, direct and indirect searches. Our proposal will be tested by DM searches, as well as by the observation of more neutrinos from blazars. Our findings motivate to implement DM-nuclei interactions in jet models and to improve our knowledge of DM spikes around active galactic nuclei.

    ↳ astro-ph.HEhep-phPRD(2025)·22 citations
26. 26*

    Bumblebee: Foundation Model for Particle Physics Discovery

    Andrew J. Wildridge🇺🇸 · Jack P. Rodgers🇺🇸 · Ethan M. Colbert🇺🇸 · Yao yao🇺🇸 · Andreas W. Jung🇺🇸 · Miaoyuan Liu🇺🇸

    Bumblebee is a foundation model for particle physics discovery, inspired by BERT. By removing positional encodings and embedding particle 4-vectors, Bumblebee captures both generator- and reconstruction-level information while ensuring sequence-order invariance. Pre-trained on a masked task, it improves dileptonic top quark reconstruction resolution by 10-20% and excels in downstream tasks, including toponium discrimination (AUROC 0.877) and initial state classification (AUROC 0.625). The flexibility of Bumblebee makes it suitable for a wide range of particle physics applications, especially the discovery of new particles.

    ↳ hep-excs.LGhep-ph13 citations
27. 27*

    The center-symmetric Landau gauge meets the lattice

    Duifje Maria van Egmond🇧🇷 · Orlando Oliveira🇵🇹 · Urko Reinosa🇫🇷 · Julien Serreau🇫🇷 · Paulo J. Silva🇵🇹 · Matthieu Tissier🇫🇷

    A lattice implementation of the recently introduced center-symmetric Landau gauge is discussed and its predictions confronted with numerical Monte Carlo simulations. It is shown that the link average and the link correlators computed in that gauge are order parameters of the confinement-deconfinement transition at nonzero temperature. Strictly speaking, this requires a specific treatment of the Gribov copies that we discuss in detail. The numerical simulations comply with the theoretical predictions for the link average computed below and above the deconfinement temperature. Our results show that, within appropriately chosen gauges, one can construct local order parameters for center symmetry, as proxies for the non-local Polyakov loop.

    ↳ hep-lathep-phhep-thPRD(2025)·5 citations
28. 28*

    Constraining Asymmetric DM Properties by Black Hole Formation in Neutron Stars and Population III Stars

    Jared Diks🇺🇸 · Cosmin Ilie🇺🇸

    In this work we explore the potential for Neutron Stars (NSs) at the Galactic center and Population~III stars to constrain bosonic Asymmetric Dark Matter (ADM). We demonstrate that for NSs in an environment of sufficiently high DM density (${\rho }_{\chi }\gtrsim 10^9{\text{GeV/cm}}^3$), the effects of both multiscatter capture and DM evaporation cannot be neglected. Conversely, for Pop~III stars, we find they are excellent at probing low-mass ADM. For instance, the most easily observable Population III stars could be highly effective at constraining high-$\sigma$ low-$m_{\chi }$ DM, maintaining efficacy below $m_{\chi }=10^{-15}\text{GeV}$ (assuming a Bose Einstein Condensate(BEC) forms) thanks to their far lower value of $m_{\chi }$ at which capture saturates to the geometric limit. Finally, we derive closed-form approximations for the evaporation rate of DM from arbitrary polytropic objects and from DM particles in a BEC state.

    ↳ astro-ph.COhep-phJCAP(2025)·2 citations
29. 29*

    SS433 Microquasar Jet and the TeV Resurgence beam

    D.Fargion🇮🇹

    The understanding of microquasars in our galaxy is one of the frontiers of high energy astrophysics. Their models are based on a capturing mass Black Hole, with a nearby spiraling binary companion star. The companion star mass feeds the accretion disk around the Black Hole. This energy also fuels an orthogonal precessing X gamma jets. The spiral precessing tail of such microquasars, as the SS433 system, is due to an ultra-relativistic jet, spraying nucleons and electrons at relativistic speeds. The up-down jet is observable in radio, X, gamma spectra. Its long spirals are spread and diluted within a light-year distance. The source is inside the W50 supernova remnant nebula , whose asymmetry reflects the past and present role of the SS433 jet. Very recently HESS, HAWC discovered, surprisingly at a much far disconnected distance from the SS433, the resurgence of a twin gamma beam tail. Nearly 75 years light distance far away from the same inner jet source. The recent standard model is based on an accelerating shock wave which reaccelerates, the resurgence of a PeV nucleon beam and its TeV secondaries. The surprising recollimation of this TeV beam jet is difficult to be accepted, in the assumption of a planarlike Fermi shock wave model. Here we discuss an alternative framework based on known high energy nuclear physics, capable to simultaneously explaining both the disconnected and the aligned hard TeV jet appearance. Several consequences, that might also be able to validate the model, are considered.

    ↳ astro-ph.HEhep-phProceedings to the 27th Workshop, What Co…·2 citations
30. 30*

    Isolated Black Holes as Potential PeVatrons and Ultrahigh-energy Gamma-ray Sources

    Shigeo S. Kimura🇯🇵 · Kengo Tomida🇯🇵 · Masato I.N. Kobayashi🇩🇪 · Koki Kin🇯🇵 · Bing Zhang🇺🇸

    The origin of PeV cosmic rays is a long-standing mystery, and ultrahigh-energy gamma-ray observations would play a crucial role in identifying it. Recently, LHAASO reported the discovery of ``dark'' gamma-ray sources that were detected above 100 TeV without any GeV--TeV gamma-ray counterparts. The origins of these dark gamma-ray sources are unknown. We propose isolated black holes (IBHs) wandering in molecular clouds as the origins of PeV cosmic rays and LHAASO dark sources. An IBH accretes surrounding dense gas, which forms a magnetically arrested disk (MAD) around the IBH. Magnetic reconnection in the MAD can accelerate cosmic-ray protons up to PeV energies. Cosmic-ray protons of GeV-TeV energies fall to the IBH, whereas cosmic-ray protons at sub-PeV energies can escape from the MAD, providing PeV CRs into the interstellar medium. The sub-PeV cosmic-ray protons interact with the surrounding molecular clouds, producing TeV-PeV gamma rays without emitting GeV-TeV gamma rays. This scenario can explain the dark sources detected by LHAASO. Taking into account the IBH and molecular cloud distributions in our Galaxy, we demonstrate that IBHs can provide a significant contribution to the PeV cosmic rays observed on Earth. Future gamma-ray detectors in the southern sky and neutrino detectors would provide a concrete test to our scenario.

    ↳ astro-ph.HEhep-phApJL(2025)·7 citations
31. 31*

    The Vanishing of the Non-linear Static Love Number of Kerr Black Holes and the Role of Symmetries

    L.-R. Gounis (NTUA)🇬🇷 · A. Kehagias (NTUA)🇬🇷 · A. Riotto (University of Geneva)🇨🇭

    We investigate the tidal response of Kerr black holes in four-dimensional space-times subjected to external gravitational fields. Using the Ernst formalism and Weyl coordinates, we analyze the non-linear tidal deformation of rotating black holes and demonstrate that their static tidal Love numbers vanish at all orders of the external tidal field. We also show that this result is intimately related to the presence of underlying non-linear symmetries. Our analysis generalizes previous findings for Schwarzschild black holes and confirms the robustness of four-dimensional black holes against tidal forces.

    ↳ gr-qchep-phhep-thJCAP(2025)·35 citations
32. 32*

    Hypothetical Lorentz invariance violation and the muon content of extensive air showers

    Nickolay S. Martynenko🇷🇺 · Grigory I. Rubtsov🇷🇺 · Petr S. Satunin🇷🇺 · Andrey K. Sharofeev🇷🇺 · Sergey V. Troitsky🇷🇺

    Extensive air showers (EAS), produced by cosmic rays in the atmosphere, serve as probes of particle interactions, providing access to energies and kinematical regimes beyond the reach of laboratory experiments. Measurements from multiple cosmic-ray detectors indicate a significant, yet unexplained, discrepancy between the observed muon content in EAS and that predicted by state-of-the-art interaction models, suggesting a need for refinements in our understanding of fundamental physics. Here we show that a tiny, experimentally allowed, violation of the Lorentz invariance (LIV) may result in the suppression of the number of electrons in EAS, leaving the muon number intact and explaining both the ''muon excess'' and its energy dependence. On the other hand, we use the lack of a much stronger discrepancy between EAS data and simulations to obtain strict constraints on the LIV scale. Future experimental tests of this LIV scenario are outlined.

    ↳ astro-ph.HEhep-phPRD(2025)·6 citations
33. 33*

    Construction of fuzzy dark matter halos with arbitrary initial velocities

    Yu-Ming Yang🇨🇳 · Xiao-Jun Bi🇨🇳 · Peng-Fei Yin🇨🇳

    Cosmological simulations of fuzzy dark matter (FDM) are computationally expensive, and the resulting halos lack flexibility in parameter adjustments, such as virial mass, density profile, and global velocity. Previous studies have introduced a method for constructing FDM halos with predefined density profiles. In this study, we investigate the initial global velocity of these constructed halos and find that it is nonzero. We provide the theoretical formula for this velocity and illustrate that it arises from the interference between states of odd and even parity. Our calculated results closely match simulation outcomes. Additionally, we showcase how to counteract this velocity and create a halo with a customizable initial global velocity. Our study presents a practical method for adjusting the initial global velocity of halos in controlled FDM simulations, facilitating investigations into tidal effects, galaxy collisions, and other scenarios.

    ↳ astro-ph.COastro-ph.GAhep-phPRD(2025)·6 citations
34. 34*

    Pulsar Kick: Status and Perspective

    Gaetano Lambiase🇮🇹 · Tanmay Kumar Poddar🇬🇧

    The high speeds seen in rapidly rotating pulsars after supernova explosions present a longstanding puzzle in astrophysics. Numerous theories have been suggested over the years to explain this sudden "kick" imparted to the neutron star, yet each comes with its own set of challenges and limitations. Key explanations for pulsar kicks include hydrodynamic instabilities in supernovae, anisotropic neutrino emission, asymmetries in the magnetic field, binary system disruption, and physics beyond the Standard Model. Unraveling the origins of pulsar kicks not only enhances our understanding of supernova mechanisms but also opens up possibilities for exploring new physics. In this brief review, we will introduce pulsar kicks, examine the leading hypotheses, and explore future directions for this intriguing phenomenon.

    ↳ astro-ph.HEgr-qchep-phSymmetry(2024)·5 citations
35. 35*

    Thermodynamics and DC conductivity of 2D anisotropic fluids from axion holography

    Alfonso Ballon-Bayona🇧🇷 · Jonathan P. Shock🇿🇦 · Dimitrios Zoakos🇬🇷

    We investigate a strongly coupled finite-density anisotropic fluid in $2+1$ dimensions dual to an asymptotically AdS black brane that is a solution of Einstein-Maxwell-Axion theory in $3+1$ dimensions. Despite the anisotropy, the fluid thermodynamic properties align with those of a conformal fluid. Moreover, we show that the fluid is stable under the increase of the anisotropy parameter. Additionally, we analyse the DC conductivity of the anisotropic fluid, showing its compatibility with momentum dissipation due to translational symmetry breaking. In the limit of very large anisotropy we find that the DC conductivity vanishes as a consequence of dimensionality reduction. We also find that a metal-insulator transition arises driven by the anisotropy.

    ↳ hep-thcond-mat.str-elhep-phJHEP(2025)·0 citations
36. 36*

    Lectures in Quantum Gravity

    Ivano Basile🇩🇪 · Luca Buoninfante🇳🇱 · Francesco Di Filippo🇨🇿 · Benjamin Knorr🇩🇪 · Alessia Platania🇩🇰 · Anna Tokareva🇨🇳

    Formulating a quantum theory of gravity lies at the heart of fundamental theoretical physics. This collection of lecture notes encompasses a selection of topics that were covered in six mini-courses at the Nordita PhD school "Towards Quantum Gravity". The scope was to provide a coherent picture, from its foundation to forefront research, emphasizing connections between different areas. The lectures begin with perturbative quantum gravity and effective field theory. Subsequently, two ultraviolet-complete approaches are presented: asymptotically safe gravity and string theory. Finally, elements of quantum effects in black hole spacetimes are discussed.

    ↳ hep-thastro-ph.COgr-qchep-ph+1SciPost Phys.Lect.Notes(2025)·51 citations
37. 37*

    The EFT of Large Spin Mesons

    Gabriel Cuomo🇺🇸 · Sergei Dubovsky🇺🇸 · Guzmán Hernández-Chifflet🇺🇾 · Alexander Monin🇺🇸 · Shahrzad Zare🇺🇸

    We use effective string theory to study mesons with large spin $J$ in large $N_c$ QCD as rotating open strings. In the first part of this work, we formulate a consistent effective field theory (EFT) for open spinning strings with light quarks. Our EFT provides a consistent treatment of the endpoints' singularities that arise in the massless limit. We obtain results, in a systematic $1/J$ expansion, for the spectrum of the leading and daughter Regge trajectories. Interestingly, we find that the redshift factor associated with the quarks' acceleration implies that the applicability regime of the EFT is narrower compared to that of static flux tubes. In the second part of this work, we discuss several extensions of phenomenological interests, including mesons with heavy quarks, the quarks' spin and the daughter Regge trajectories associated with the worldsheet axion, a massive string mode identified in lattice simulations of $4d$ flux tubes. We compare our predictions with $4d$ QCD spectroscopy data, and suggest potential $stringy$ interpretations of the observed mesons. We finally comment on the relation between the EFT spectrum and the Axionic String Ansatz, a recently proposed characterization of the spectrum of Yang-Mills glueballs.

    ↳ hep-thhep-lathep-phJHEP(2025)·5 citations
38. 38*

    Visions in Quantum Gravity

    Luca Buoninfante🇳🇱 · Benjamin Knorr🇩🇪 · K. Sravan Kumar🇬🇧 · Alessia Platania🇩🇰 · Damiano Anselmi🇮🇹 · Ivano Basile🇩🇪 · N. Emil J. Bjerrum-Bohr🇩🇰 · Robert Brandenberger🇨🇦 · Mariana Carrillo González🇬🇧 · Anne-Christine Davis🇬🇧 · Bianca Dittrich🇨🇦 · Paolo Di Vecchia🇸🇪 and 27 other authors

    To deepen our understanding of Quantum Gravity and its connections with black holes and cosmology, building a common language and exchanging ideas across different approaches is crucial. The Nordita Program "Quantum Gravity: from gravitational effective field theories to ultraviolet complete approaches" created a platform for extensive discussions, aimed at pinpointing both common grounds and sources of disagreements, with the hope of generating ideas and driving progress in the field. This contribution summarizes the twelve topical discussions held during the program and collects individual thoughts of speakers and panelists on the future of the field in light of these discussions.

    ↳ hep-thastro-ph.COgr-qchep-ph+1SciPost Phys.Comm.Rep.(2025)·49 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.