Tue·Aug 12, 2025Tuesday·August 12, 2025

1. 01*

   Leptogenesis and Dirac neutrino masses in SO(10)

   R. Aleksan🇫🇷 · L. Oliver🇫🇷

   Within the scheme of Baryogenesis through Leptogenesis in the single flavor approximation, we emphasize the role of the Dirac neutrino mass $m_D$ in the SO(10) Grand Unification scheme, using the Higgs representations for the fermions masses $10$ and $\overline{126}$. Both representations are needed to get relations among the fermion masses, e.g. $m_b=m_{\tau }$, $m_{\mu }=3m_s$,... Taking these two representations allow to relax the condition $m_D=m_u$ obtained with the representation $10$ alone and to have general Dirac masses $m_D\ne m_u$. On the other hand, we assume that the antisymmetric representation $120$ is absent. Within this hypothesis, the unitary matrices $V^L$ and $V^R$ that diagonalize $m_D$ through $m_D=V^{L†}{m}_D^{diag}{V}^R$ still satisfy the relation $V^R=V^{L\ast }$. Under these conditions, unlike the case of keeping only the $10$ representation, we obtain in parameter space several examples of the heavy neutrino spectrum consistent with the SO(10) unification scale, and a value for the baryon asymmetry $Y_B$ in agreement with data. For illustration, we detail a case that gives the heavy spectrum with masses $M_1=6.26\times 10^{10}\mathrm{GeV}$, $M_2=2.23\times 10^{12}\mathrm{GeV}$, $M_3=4.57\times 10^{14}\mathrm{GeV}$ and, in the strong washout regime, the baryon asymmetry $Y_B=8.50\times 10^{-11}$ consistent with the data.

   hep-phhep-th0 citations
2. 02*

   Exclusive $J/\psi +\gamma$ production in ultraperipheral ion collisions

   Zi-Qiang Chen🇨🇳 · Long-Bin Chen🇨🇳

   Ultraperipheral collisions (UPCs) of ions provide new opportunities to study the quarkonium production mechanism in photon-photon scattering. In this paper, we investigate the exclusive process $\gamma +\gamma \to J/\psi +\gamma$ up to $\mathcal{O}({\alpha }_s{v}^2)$ accuracy within the nonrelativistic quantum chromodynamics factorization framework. We evaluate the corresponding cross sections for Pb-Pb and p-p UPCs at the Large Hadron Collider. Numerical results show that the $\mathcal{O}({\alpha }_s)$, $\mathcal{O}(v^2)$, and $\mathcal{O}({\alpha }_s{v}^2)$ corrections are about $-50\%$, $-33\%$, and $15\%$ of the leading-order (LO) contribution, respectively, showing reasonable convergence in both ${\alpha }_s$ and $v^2$ expansion. Collectively, these corrections suppress the LO cross section by a factor of about $1/3$, which is a crucial effect for reliable phenomenological analysis. Our results suggest that future experimental measurements of this process are feasible.

   hep-phPRD(2025)·2 citations
3. 03*

   Bounding exotic top decays inclusively at the FCC-ee

   Gennaro Corcella🇮🇹 · Barbara Mele🇮🇹 · Dibyashree Sengupta🇮🇹

   Since its discovery, the top quark has never been produced and studied in an environment as clean as that predicted for $e^{+}{e}^{-}$ collisions at future colliders. Details of the top quark's properties, completely unattainable in hadronic collisions, can be analyzed via lepton collisions. New strategies for analyzing the physics of the top quark can, therefore, be developed in such a spectacularly clean environment. Here we focus on the possibility of inclusively measuring exotic excesses in the top decay width by studying the direct production of $t\bar{t}$ at the FCC-$ee$, thus establishing model-independent limits for rare decays branching fractions of the top quark.

   hep-phhep-ex1 citation
4. 04*

   Bridging doubly heavy tetraquark mass spectrum with heavy baryons utilizing heavy antiquark-diquark symmetry

   Liu-Yu Zhang🇨🇳 · Tian-Wei Wu🇨🇳 · Yong-Liang Ma🇨🇳

   Motivated by the observation of the doubly charmed tetraquark $T_{cc}(3875{)}^{+}$, we present a systematic study of double heavy tetraquarks ($T_{Q{Q}^{\prime }\bar{q}{\bar{q}}^{\prime }}$) using heavy antiquark-diquark symmetry (HADS) within a constituent quark model. By calibrating model parameters to known hadron spectra and incorporating the effective mass formula, we predict the masses for 38 ground-state tetraquarks with $cc$, $bb$, and $bc$ heavy quark pairs, including the non-strange, single-strange, and double-strange configurations with quantum numbers $J^P=0^{+},1^{+}$ and $2^{+}$. Notably, we identify several stable states below the relevant meson-meson thresholds, particularly in the $bb\bar{q}{\bar{q}}^{\prime }$ sector. The explicit connection between doubly heavy tetraquark and heavy baryon spectra through HADS reduces model dependence and reveals fundamental systematics in the heavy-quark hadron landscape.

   hep-phCPC(2026)·1 citation
5. 05*

   Nonfactorizable charming loops in exclusive FCNC $B$ decays

   Dmitri Melikhov🇷🇺

   We compare (i) nonfactorizable charm-quark loops in exclusive FCNC B-decays and (ii) three-particle contributions to the amplitude of semileptonic B-decay. Both amplitudes are given in the heavy-quark limit, $m_b\to \infty$, by a convolution of a hard kernel and a three-particle wave function of the $B$-meson, $⟨0|\bar{q}(x)G_{\mu \nu }(z)b(0)|B(p)⟩$. An essential difference between the two amplitudes is that the amplitude of semileptonic $B$-decay involves this 3-particle wave function in a collinear light-cone configuration, whereas the amplitude of nonfactorizable charm in FCNC $B$-decays involves this 3-particle wave function in a double collinear light-cone configuration.

   hep-phMoscow Univ.Phys.Bull.(2025)·0 citations
6. 06*

   Constraints on the Variation of the QCD Interaction Scale ${\Lambda }_{\text{QCD}}$

   V. V. Flambaum🇦🇺 · A. J. Mansour🇦🇺

   Laboratory and astrophysical tests of ''constant variation'' have so far concentrated on the dimensionless fine-structure constant $\alpha$ and on the electron or quark mass ratios $X_{e,q}=m_{e,q}/{\Lambda }_{\text{QCD}}$, treating the QCD scale ${\Lambda }_{\text{QCD}}$ as unchangeable. Certain beyond Standard Model frameworks, most notably those with a dark matter or dark energy scalar field $\varphi$ coupling with the gluon field, would make ${\Lambda }_{\text{QCD}}$ itself time dependent while leaving $\alpha$ and the electron mass untouched. Under the minimal assumption that this gluonic channel is the sole $\varphi$ interaction, we recast state-of-the-art atomic clock comparisons into ${\dot{\Lambda }}_{\text{QCD}}/{\Lambda }_{\text{QCD}}=(3.2\pm 3.5)\times 10^{-17}{\text{yr}}^{-1}$ limits, translate the isotope yields of the 1.8-Gyr-old Oklo natural reactor into a complementary geophysical limit of $|\delta {\Lambda }_{\text{QCD}}/{\Lambda }_{\text{QCD}}|<2\times 10^{-9}$ over that time span, corresponding to the linear drift limit $|{\dot{\Lambda }}_{\text{QCD}}/{\Lambda }_{\text{QCD}}|<1\times 10^{-18}{\text{yr}}^{-1}$, and show that the proposed $8.4$ eV ${}^{229}$Th nuclear clock would amplify a putative ${\Lambda }_{\text{QCD}}$ drift by four orders of magnitude compared with present atomic clocks. We also obtain constraints from quasar absorption spectra and Big Bang Nucleosynthesis data.

   hep-phastro-ph.COnucl-thphysics.atom-phJHEP(2025)·1 citation
7. 07*

   Puzzle for the Vector Meson Threshold Photoproduction

   Igor Strakovsky (GWU)🇺🇸

   High-statistics total cross sections for the vector meson photoproduction at the threshold: $\gamma p\to \omega p$ (from A2 at MAMI, ELPH, and CBELSA/TAPS), $\gamma p\to \varphi p$ (from CLAS and LEPS), and $\gamma p\to J/\psi p$ (from GlueX) allow one to extract the absolute value of vector meson nucleon scattering length using Vector Meson Dominance (VMD) model. The ``young'' vector meson hypothesis may explain the fact that the obtained scattering length value for the nucleon $\varphi$-meson compared to the typical hadron size of approximately $\sim 1\mathrm{fm}$ indicates that the proton is more transparent for the $\varphi$-meson compared to the $\omega$-meson and is much less transparent than the $J/\psi$-meson. The extended analysis of ${\rm Y}$-meson photoproduction using quasi-data from the QCD approach is in perfect agreement with the light-meson findings using experimental data. Future high-quality experiments by EIC and EicC will have the opportunity to evaluate cases for $J/\psi$- and ${\rm Y}$-mesons. It allows one to understand the dynamics of $c\bar{c}$ and $b\bar{b}$ production at the threshold. The ability of J-PARC to measure ${\pi }^{-}p\to \varphi n$ and ${\pi }^{-}p\to J/\psi n$, which are free from the VMD model, is considered.

   hep-phhep-exnucl-exnucl-thPoS(2025)·0 citations
8. 08*

   Impact of Primordial Magnetic Fields on the First-Order Electroweak Phase Transition

   Yuefeng Di🇨🇳 · Ligong Bian🇨🇳 · Rong-Gen Cai🇨🇳

   We numerically study how the primordial magnetic field affects the first-order electroweak phase transition in the early Universe. We observe that: 1) the phase transition process would be slowed down by the magnetic field; 2) the phenomenon of vortex structure of the Higgs condensation appears when the homogenesis hypermagentic field $g^{\prime }{B}_Y^{ex}/m_W^2\gtrsim 3.63$; and, 3) the helical hypermagnetic field can dramatically enhance the sphaleron rate and validate the generation of the baryon asymmetry through the chiral anomaly.

   hep-phastro-ph.COhep-lathep-thPRD(2026)·8 citations
9. 09*

   Flow in small systems in the EPOS4 approach for high-energy scatterings

   Klaus Werner🇫🇷

   EPOS4 is based on a sophisticated (recently significantly improved) parallel-primary-scattering scenario followed by a hydrodynamic expansion, for all collision systems, from small ones such as proton-proton ($pp$) to big ones such as lead-lead (PbPb). Having already reported on identified particle spectra in recent publications (providing information about radial flow), I discuss here the multiplicity dependence of multi-particle cumulants and flow harmonics, to better understand collectivity in small systems. The model is not particularly tuned for flow results, but it is a "general purpose" approach, trying to accommodate various types of observables with the same model.

   hep-phPRC(2026)·3 citations
10. 10*

    Investigating 1-Bit Quantization in Transformer-Based Top Tagging

    Saurabh Rai🇮🇳 · Prisha🇮🇳 · Jitendra Kumar🇮🇳

    The increasing scale of deep learning models in high-energy physics (HEP) has posed challenges to their deployment on low-power, latency-sensitive platforms, such as FPGAs and ASICs used in trigger systems, as well as in offline data reconstruction and processing pipelines. In this work, we introduce BitParT, a 1-bit Transformer-based architecture designed specifically for the top-quark tagging method. Building upon recent advances in ultra-low-bit large language models (LLMs), we extended these ideas to the HEP domain by developing a binary-weight variant (BitParT) of the Particle Transformer (ParT) model. Our findings indicate a potential for substantial reduction in model size and computational complexity, while maintaining high tagging performance. We benchmark BitParT on the public Top Quark Tagging Reference Dataset and show that it achieves competitive performance relative to its full-precision counterpart. This work demonstrates the design of extreme quantized models for physics applications, paving the way for real-time inference in collider experiments with minimal and optimized resource usage.

    hep-phEPJC(2026)·5 citations
11. 11*

    A search for anomalous quartic gauge couplings in lead-lead collisions at the FCC-hh

    S.C. İnan🇹🇷 · A.V. Kisselev🇷🇺

    A sensitivity of the collider FCC-hh to anomalous quartic gauge couplings (aQGCs) of neutral bosons in lead-lead collisions is studied. Examining diphoton production, the bounds on aQGCs at $5\sigma$ and 95\% C.L. are obtained depending on systematic uncertainties.

    hep-phhep-exJHEP(2025)·0 citations
12. 12*

    On phenomenological relations for masses and mixing parameters of quarks and leptons

    V. V. Khruschov🇷🇺 · S. V. Fomichev🇷🇺

    A comparative analysis of a number of phenomenological relationships between constants of the extended Standard Model of electromagnetic, strong and weak interactions of fundamental particles (hereinafter referred to as the extended Standard Model) is carried out to detect possible correlations between constants in the quark and lepton sectors. The presence of such correlations may indicate connections between constants within a more general theory than the extended Standard Model. Phenomenological relationships between masses of current and constituent quarks and mixing angles are considered. A phenomenological relationship between neutrino masses and neutrino mixing angle is found. The quark-lepton complementarity relationship for quark and neutrino mixing angles is confirmed. A typical estimate of the accuracy of such relationships is given. Estimates of the masses of sterile (right-handed) neutrinos are obtained at the phenomenological level using the seesaw mechanism. In this case, it is assumed that the values of the active neutrino masses depend on three characteristic scales, and the sum of the active neutrino masses is limited from above by $0.06$~eV. An example of a grand unification theory and possible stages of spontaneous breaking of its gauge symmetry to the level of gauge symmetry of the extended Standard Model due to additional Higgs particles are considered.

    hep-ph1 citation
13. 13*

    Partial pressure and susceptibilities of charmed sector in the van der Waals hadron resonance gas model

    Kangkan Goswami🇮🇳 · Kshitish Kumar Pradhan🇮🇳 · Dushmanta Sahu🇲🇽 · Raghunath Sahoo🇮🇳

    We investigate the general susceptibilities in the charm sector by using the van der Waals hadron resonance gas model (VDWHRG). We argue that the ideal hadron resonance gas (HRG), which assumes no interactions between hadrons, and the excluded volume hadron resonance gas (EVHRG), which includes only repulsive interactions, fail to explain the lQCD data at very high temperatures. In contrast, the VDWHRG model, incorporating both attractive and repulsive interactions, extends the degree of agreement with lQCD up to nearly 180 MeV. We estimate the partial pressure in the charm sector and study charm susceptibility ratios in a baryon-rich environment, which is tricky for lattice quantum chromodynamics (lQCD) due to the fermion sign problem. Our study further solidifies the notion that the hadrons shouldn't be treated as non-interacting particles, especially when studying higher order fluctuations, but rather one should consider both attractive and repulsive interactions between the hadrons.

    hep-phhep-exhep-latnucl-ex+1PRD(2026)·2 citations
14. 14*

    Monte Carlo study of KDAR ${\nu }_{\mu }$ charged-current scattering on carbon

    Ritesh Kumar Pradhan🇮🇳 · Ralte Lalnuntluanga🇮🇱 · Anjan Giri🇮🇳

    The neutrino energy reconstruction is crucial for reducing systematic uncertainties in neutrino oscillation experiments and improving cross-section measurements. Kaon-Decays-At-Rest (KDAR) neutrinos provide a unique opportunity to probe neutrino-nucleus interactions at low energies with a precisely known energy of 235.5 MeV. This work presents Monte Carlo predictions of missing energy due to nuclear effects in the KDAR ${\nu }_{\mu }$ charged-current scattering on the carbon nucleus for JSNS${}^2$. The predictions from GENIE, NuWro, and GiBUU show a significant impact of nuclear and final state interaction (FSI) models, as well as nucleon removal energy, on missing energy reconstruction. Tuning the hA FSI model improves the predictions from GENIE. It is also observed that the nucleon elastic component of FSI leads to better predictions in NuWro compared to GENIE. NuWro shows the best agreement with data among the generators considered; however, the observed discrepancies with data across all generators highlight the limitations of current theoretical descriptions in the low-energy regime and the need for improvements in Monte Carlo modeling.

    hep-phhep-exPRD(2025)·0 citations
15. 15*

    Vector meson dominance in photon structure functions at small $x$ from holography

    Wei Gao🇨🇳 · Siming Liu🇨🇳 · Wenbin Lin🇨🇳 · Akira Watanabe🇯🇵

    We investigate the photon structure functions via the photon-photon and photon-vector meson scattering within the framework of holographic QCD, focusing on the small Bjorken $x$ region and assuming that the Pomeron exchange dominates. The quasi-real photon structure functions are formulated as the convolution of the known U(1) vector field wave function with the Brower-Polchinski-Strassler-Tan (BPST) Pomeron exchange kernel in the five-dimensional AdS space. Assuming the vector meson dominance, the photon structure functions can be calculated in a different way with the BPST kernel and vector meson gravitational form factor, which can be obtained in a bottom-up AdS/QCD model, for the Pomeron-vector meson coupling. It is shown that the obtained $F_2$ structure functions in the both ways agree with the experimental data, which implies the realization of the vector meson dominance within the present model setup. Calculations for the longitudinal structure function and the longitudinal-to-transverse ratio are also presented.

    hep-phhep-exnucl-exnucl-thPRD(2025)·0 citations
16. 16*

    Light baryonium states with exotic quantum numbers

    Bing-Dong Wan🇨🇳 · Jun-Hao Zhang🇨🇳 · Yan Zhang🇨🇳 · Ming-Yang Yuan🇨🇳

    The existence of baryonium-bound or resonant states composed of a baryon and an antibaryon has long been postulated as a natural extension of conventional hadron spectroscopy. In the present work, we conduct a systematic investigation of the mass spectrum and internal configurations of light baryonium candidates exhibiting exotic quantum numbers that are inaccessible within the framework of the traditional quark model. Employing the method of QCD sum rules, we analyze nucleon-antinucleon and light hyperon-anti-hyperon systems with quantum numbers $J^{PC}=0^{--}$ and $0^{+-}$, which are quantum number combinations prohibited for conventional mesonic states. Our analysis reveals the potential existence of two $0^{--}$ $\Lambda$-$\bar{\Lambda }$ baryonium states with masses $(2.90\pm 0.09)$ GeV and $(3.36\pm 0.09)$ GeV, respectively, as well as two $0^{+-}$ $\Lambda$-$\bar{\Lambda }$ states with masses $(2.91\pm 0.07)$ GeV and $(3.29\pm 0.07)$ GeV, respectively. In addition, corresponding nucleon-antinucleon partner states are identified at $(2.69\pm 0.07)$ GeV, $(3.07\pm 0.08)$ GeV, $(2.86\pm 0.07)$ GeV, and $(3.22\pm 0.07)$ GeV, respectively. Furthermore, analogous $\Xi$-$\bar{\Xi }$ configurations are predicted with masses of $(3.10\pm 0.09)$ GeV, $(3.54\pm 0.07)$ GeV, $(3.08\pm 0.08)$ GeV, and $(3.45\pm 0.08)$ GeV, respectively. The possible decay modes of the light exotic baryonium states are analyzed, which are hopefully measurable in BESIII, BELLEII, and LHCb experiments.

    hep-phEPJC(2026)·7 citations
17. 17*

    A Novel Neutrino Mass Matrix

    Pralay Chakraborty🇮🇳 · Sagar Tirtha Goswami🇮🇳 · Subhankar Roy🇮🇳

    A predictive neutrino mass matrix texture, sheltering unique correlations ($m_{12}=m_{13}\&m_{33}=2i{m}_{12}$), is proposed, addressing most of the timely neutrino phenomenology issues. The texture is realized in the framework of type-I + type-II seesaw in the light of the $A_4\times Z_{10}\times Z_7\times Z_3$ group. The stability of the proposed texture is studied under renormalization group evolution.

    hep-ph2 citations
18. 18*

    The quest for a Quark-Gluon Plasma

    Edward Shuryak🇺🇸

    A chapter in a book"50 years of QGP" An extended summary of the field can be found in large books and reviews, e.g., my take in Ref.~\cite{Shuryak:2024zrh}. It is hard to compress its 600+ pages and 50+ years of research to a few given below. Those include only recollection of few episodes, from early days to now, showing how vague dreams were eventually turning into solid and detailed scientific facts.

    hep-ph1 citation
19. 19*

    Chiral enhancement in soft-photon bremsstrahlung and charge asymmetry in low-energy lepton-proton scattering

    Bhoomika Das🇮🇳 · Rakshanda Goswami🇮🇳 · Pulak Talukdar🇮🇳 · Udit Raha🇮🇳 · Fred Myhrer🇺🇸

    We carry out a Lorentz gauge evaluation of the single-soft photon bremsstrahlung radiative corrections to the unpolarized elastic lepton-proton scattering cross section at low energies using the framework of heavy baryon chiral effective field theory (HB$\chi$PT). We systematically incorporate all next-to-leading order [i.e., $\mathcal{O}({\alpha }^3/M)$] contributions to the cross section arising from radiative and proton's low-energy recoil effects. An important component of the soft-photon bremsstrahlung corrections arises from the interference between lepton and proton bremsstrahlung processes, which are characterized as charge-odd. We identify a class of Feynman diagrams involving the final-state radiating proton that induces a chiral enhancement, thereby modifying the naive amplitude hierarchy based on the standard chiral power-counting scheme. The recently derived HB$\chi$PT result for the analytically computed exact two-photon exchange (TPE) counterpart at NLO is combined with our charge-odd soft-photon bremsstrahlung contribution to yield the complete charge-odd radiative correction. By incorporating the leading hadronic correction to the leading order Born one-photon exchange (OPE) process within the charge-even radiative correction, we obtain a prediction for the charge asymmetry observable, which can be compared with forthcoming MUSE data on elastic lepton-anti-lepton scattering off the proton. In all our calculations, we use finite lepton masses.

    hep-phnucl-thPRD(2026)·2 citations
20. 20*

    Anisotropic Gravitational Waves from Anisotropic Axion Rotation

    Arushi Bodas🇺🇸 · Keisuke Harigaya🇺🇸 · Keisuke Inomata🇺🇸 · Takahiro Terada🇯🇵 · Lian-Tao Wang🇺🇸

    Gravitational waves (GWs) provide a powerful probe of the early universe due to their ability to free-stream across cosmic history. We study GW production in a compelling scenario where a rotating axion(-like) field becomes relevant for a brief period in the early universe before transitioning into a kination fluid and rapidly dissipating its energy through cosmic expansion. During this short epoch, the curvature perturbation can be predominantly sourced by the rotating axion and may significantly exceed the adiabatic component. Moreover, axion field perturbations grow on superhorizon scales during this phase. These effects can generate a strong stochastic background of induced GWs. This GW background also exhibits a pronounced large-scale anisotropy inherited from the axion fluctuations, serving as a distinctive signature of the scenario. Importantly, the transient nature of axion relevance enables this scenario to evade stringent bounds on large-scale perturbations. We analyze various observational constraints and find that both the amplitude and anisotropy of the resulting GW signal could be accessible to future detectors.

    hep-phastro-ph.COhep-thJHEP(2026)·6 citations
21. 21*

    ALPaca: The ALP Automatic Computing Algorithm

    Jorge Alda🇮🇹 · Marta Fuentes Zamoro🇪🇸 · Luca Merlo🇪🇸 · Xavier Ponce Díaz🇨🇭 · Stefano Rigolin🇮🇹

    The ALP Automatic Computing Algorithm, ALPaca, is an open source Python library devoted to studying the phenomenology of Axion-Like Particles (ALPs) with masses in the ranges $m_a\in [0.01-10]$ GeV. ALPaca provides a flexible and comprehensive framework to define ALP couplings at arbitrary energy scales, perform Renormalisation Group evolution and matching down to the desired low energy scale, and compute a large variety of ALP observables, with particular care to the meson decay sector. The package includes support for UV completions, experimental constraints, and visualisation tools, enabling both detailed analyses and broad parameter space exploration.

    hep-phhep-ex9 citations
22. 22*

    Super-heated first order phase transitions

    Giulio Barni🇪🇸 · Andrea Tesi🇮🇹

    We study first order phase transitions that occur when the temperature of the system increases and we identify the conditions that lead to super-heating, a phase where the system can heat up arbitrarily. First order phase transitions with super-heating behave as inverse transitions. We quantify these claims by studying a prototypical example of a dark sector with a large number of interacting light bosons at finite temperature. Depending upon thermalisation, a super-heated phase transition in cosmology is often associated with another transition when the system is eventually cooling down, enriching the spectrum of gravitational waves from bubble collisions.

    hep-phastro-ph.COhep-thJHEP(2026)·8 citations
23. 23*

    Radio Killed the Axion Star: Constraining Axion Properties with Radio Telescopes

    Patrick J. Fox🇺🇸 · Neal Weiner🇺🇸 · Huangyu Xiao🇺🇸

    Axion dark matter or any ultralight bosonic dark matter can go through Bose-Einstein condensation due to the large phase density, leading to the formation of axion stars or solitons in dark matter halo centers. The formation rate is enhanced in the presence of the substructures expected in the post-inflationary scenario for the QCD axion or axion-like particles. An axion star will continue to grow until a critical mass is reached, after which it collapses and then explodes, with the emission of relativistic axions, in a process called an ``axinovae.'' There can also be accompanying photon emission due to the stimulated decay of axions in the coherent compact axion star. In axion models with a modest enhancement ($\kappa \sim \mathcal{O}(10)$) of the axion-photon coupling $g_{a\gamma }=\kappa \alpha /(2\pi f_a)$ axinovae will contain a significant flux of radio photons. We determine the range of parameters over which axinovae can be detectable with radio transient searches.

    hep-phPRD(2026)·4 citations
24. 24*

    A Multi-Wavelength Survey of Transient Lensing Opportunities for Primordial Black Hole Searches

    Stefano Profumo🇺🇸

    Gravitational lensing of short astrophysical transients provides a uniquely direct avenue for searching for primordial black holes (PBHs) across a vast range of masses. While past search efforts have focused on particular source classes-such as fast radio bursts (FRBs) and gamma-ray burst spikes-no systematic, multi-wavelength assessment has compared their relative potential for PBH discovery. We present here a broad assessment of transient lensing search opportunities, spanning more than twenty decades in photon frequency and over twelve orders of magnitude in PBH mass. For each class, we determine the accessible PBH mass window by accounting for wave-optics suppression and time-delay resolution limits, and we estimate potential sensitivities to the PBH abundance using representative event rates, distances, and optical depths. Our survey includes low-frequency radio events (FRBs, pulsar giant pulses, planetary cyclotron bursts), optical/infrared signals, and high-energy phenomena (gamma-ray burst spikes, fast X-ray transients, TeV blazar flares). We synthesize these results in a unified mass-abundance diagram and comprehensive tables summarizing both physical reach and observational requirements. This work serves as a roadmap for optimizing future multi-wavelength lensing searches, guiding the design of instruments and strategies to explore the PBH dark matter hypothesis across its remaining viable parameter space.

    ↳ astro-ph.HEastro-ph.COhep-phJCAP(2025)·3 citations
25. 25*

    Primordial Gravitational Waves in Parity-violating Symmetric Teleparallel Gravity

    Rongrong Zhai🇨🇳 · Chengjie Fu🇨🇳 · Xiangyun Fu🇨🇳 · Puxun Wu🇨🇳 · Hongwei Yu🇨🇳

    In this paper, we investigate the inflationary phenomenology of parity-violating (PV) extensions of symmetric teleparallel gravity by applying this PV gravity theory to axion inflation. The presence of PV terms induces velocity birefringence in the tensor perturbations. During inflation, when the inflaton rapidly traverses the cliff-like region in its potential, the tensor modes at specific scales for one of the two circular polarization states undergo significant amplification due to tachyonic instability. Consequently, the resulting primordial gravitational waves (GWs), characterized by a one-handed polarization and a multi-peak structure in their energy spectrum, exhibit a significant amplitude potentially detectable by LISA and Taiji, and their chirality could be determined by the LISA-Taiji network. The detection of such a chiral GW signal provides an opportunity to probe inflation and PV gravity theory. Moreover, we perform the Fisher matrix analysis to forecast the constraints on the model parameters with the LISA-Taiji network.

    ↳ astro-ph.COgr-qchep-phPRD(2026)·2 citations
26. 26*

    EPOS.LHC-R : a global approach to solve the muon puzzle

    Tanguy Pierog🇩🇪 · Klaus Werner🇫🇷

    The hadron production in the simulation of extensive air showers is a long standing problem and the origin of large uncertainties in the reconstruction of the mass of the high energy primary cosmic rays. Hadronic interaction models re-tuned after early LHC data give more consistent results among each other compared to the first generation of models, but still can't reproduce extended air shower data (EAS) consistently resulting in the so-called "muon puzzle". Using more recent LHC data like in the QGSJET-III model improve further the description of EAS by such a model but is not enough to resolve the discrepancy. On the other hand, the EPOS project is a theoretical global approach aiming at describing data from very fundamental electron-positron interactions to central heavy ions collisions. We will demonstrate that this approach can provide new constraints, changing the correlation between the measured data at mid-rapidity and the predicted particle production at large rapidities, which drive the EAS development. Thus, using the same accelerator data, different predictions are obtained in air shower simulations in much better agreement with the current air shower data (for both the maximum shower development depth Xmax and the energy spectrum of the muons at ground). Using the EPOS LHC-R model, the detailed changes will be addressed and their consequences on EAS observable at various energies.

    ↳ astro-ph.HEhep-phPoS(2025)·20 citations
27. 27*

    The 300 TeV photon from GRB 221009A: a Hint at Non-linear Lorentz Invariance Violation?

    Dmitry D. Ofengeim🇮🇱 · Tsvi Piran🇮🇱

    The air shower array Carpet-3 detected a 300 TeV photon from the direction of GRB 221009A at 4536 s after the Fermi-GBM trigger for this event. If the association with this gamma-ray burst is real, it poses two puzzles. First, why was this photon not absorbed by the extragalactic background light? ``New physics'' beyond the Standard Model is required to explain how it managed to reach Earth from a cosmological distance. Second, why was this photon detected when the VHE afterglow observed by LHAASO already faded? A novel astrophysical mechanism is required to explain this delay. In this work we show that Lorentz invariance violation (LIV), which arises as a low-energy limit of certain quantum gravity theories, can solve both puzzles. It shifts thresholds of particle interaction and changes the opacity of the extragalactic background, and cause energy-dependent variations of the photon velocity, which changes the photon time of flight. We investigate the LIV parameter space assuming that the 300 TeV photon is a part of the VHE afterglow detected by LHAASO in the TeV range. We identify viable solutions and place stringent two-sided constraints on the LIV energy scale required to resolve the observational puzzles. First-order LIV appears to be incompatible with the constraints set by analyzing the TeV afterglow of this GRB. Viable solutions emerge for higher orders. In particular, the commonly studied second-order subluminal LIV with $E_{LIV2}=1.30_{-0.35}^{+0.56}\times 10^{-7}{E}_{\mathrm{Pl}}$ (95.4% credibility level; $E_{\mathrm{Pl}}$ is the Planck energy) is consistent with all the observed data.

    ↳ astro-ph.HEgr-qchep-phPRD(2025)·6 citations
28. 28*

    Characterizing radial flow fluctuations in relativistic heavy-ion collisions at top RHIC and LHC energies

    Lipei Du🇺🇸

    We present a systematic investigation of the transverse-momentum differential radial flow fluctuations observable $v_0(p_T)$ in relativistic heavy-ion collisions at top RHIC ($\sqrt{s_{\mathrm{NN}}}=200$ GeV) and LHC ($\sqrt{s_{\mathrm{NN}}}=2.76$ and 5.02 TeV) energies. Using a multistage hydrodynamic model, we assess the sensitivity of $v_0(p_T)$ to a wide range of physical effects, including bulk and shear viscosities, off-equilibrium corrections at particlization, the presence of a hadronic afterburner, and the nucleon size in the initial conditions. By employing complementary rescaling strategies, we demonstrate how different physical effects leave distinct imprints on the shape of $v_0(p_T)$. A combined double-rescaling of $v_0(p_T)/v_0$ versus $p_T/⟨p_T⟩$ reveals a universality across a wide range of energies and model assumptions in the low-$p_T$ regime, a robust signature of collective behavior. This allows us to disentangle the universal dynamics of the bulk medium from model-specific features that emerge at higher $p_T$. Our results establish $v_0(p_T)$ as a powerful and complementary observable for constraining QGP transport properties and initial-state granularity, offering a unique probe of the created QCD medium.

    ↳ nucl-exhep-phnucl-thPRC(2026)·16 citations
29. 29*

    Signature of polarized ultralight vector dark matter in pulsar timing arrays

    Kimihiro Nomura🇯🇵 · Hidetoshi Omiya🇯🇵 · Takahiro Tanaka🇯🇵

    We investigate observational signatures of ultralight vector dark matter with masses $m\sim 10^{-24}$-$10^{-22}$ eV in pulsar timing arrays, taking into account general polarization states of the vector field. We find that vector dark matter induces pulsar timing residuals with nontrivial directional dependence, reflecting the anisotropic property and polarization structure specific to vector dark matter, unlike scalar dark matter. We also derive angular correlation curves of the timing residuals. Intriguingly, circular polarization of the vector dark matter enhances the quadrupole nature of the correlation curve, resulting in a more notable bending of the Hellings-Downs curve. The derived correlation curves offer a useful means to distinguish gravitational wave and dark matter contributions and to probe the nature of dark matter.

    ↳ astro-ph.COgr-qchep-phPRD(2025)·3 citations
30. 30*

    Preheating and gravitational waves in large-field hilltop inflation

    Diganta Das🇮🇳 · Shreyas Revankar🇮🇳

    The combined Planck, BICEP/Keck Array and BAO measurements of the scalar spectral index and the tensor-to-scalar ratio from the cosmic microwave background observations severely constrain or completely rule out several models of inflationary potentials. On the other hand, the data seems to favor concave potentials over convex ones. In this paper, we study preheating and gravitational waves after inflation in a large-field, regularized hilltop potential where inflation takes place in the concave plateau. The inflaton, $\varphi$, is coupled to a subdominant scalar field, $\chi$, through a quartic coupling. After inflation ends, $\varphi$ oscillates about the potential minimum and becomes inhomogeneous. The growth of the fluctuation modes, $\delta {\varphi }_k$ and $\delta {\chi }_k$, in a homogeneous, oscillating background is analyzed in linear perturbation theory, revealing that small modes likely experience broad self-resonance or external parametric resonance. To determine if the resonances are sufficiently strong to cause unstable growth of the modes we perform a lattice simulation. The lattice simulations demonstrate that, although the initial inhomogeneities generate a stochastic gravitational wave background that remains below the present observational limit, the fluctuations do not grow exponentially, and the occupation numbers of $\delta {\varphi }_k$ and $\delta {\chi }_k$ remain close to zero.

    ↳ astro-ph.COgr-qchep-phEur.Phys.J.ST(2026)·0 citations
31. 31*

    Dynamical Black Hole in the accelerating Universe approaching the future singularity -- Possible origin of (super-)massive black holes

    Shin'ichi Nojiri🇯🇵 · Sergei D. Odintsov🇪🇸

    We construct and investigate the dynamical black hole spacetime embedded in the expanding universe filled with cosmic fluid, such as dark energy. When the equation of state (EoS) parameter of the fluid is a constant, we find exact solutions of the Einstein equation where the Schwarzschild black hole is embedded in the expanding universe. This solution differs from the well-known McVittie metric, where the EoS parameter is not a constant but rather depends on the radial coordinate. It is shown that a dynamical black hole grows with the expansion of the universe. If primordial black holes are created before or during inflation, above dynamical black holes might be the origin of the supermassive black holes at the centre of galaxies, massive black holes suggested by the GW231123 event, and also the dark matter. The case where the cosmic fluid EoS is more general is also considered so that the universe enters the epoch of finite-time future singularity. Thermodynamics and the behaviour of black holes around different future singularities are carefully investigated. It is then demonstrated that the black hole horizon enhances the tidal force, but near the horizon, the tidal force works to press the extended object, which is in contrast with a massive body near to future singularity. We also propose a new type of future singularity where the singularity inside the black hole is a sphere with a finite radius. When the radius of the spherical singularity becomes larger than the radius of the black hole horizon, it becomes naked. The universe may end up with a cosmic doomsday when the radius of the singularity becomes infinite.

    ↳ gr-qcastro-ph.COhep-phhep-thPhys.Dark Univ.(2025)·7 citations
32. 32*

    Leading-Order QCD Equation of State in Strong Magnetic Fields at Nonzero Baryon Chemical Potential

    Heng-Tong Ding🇨🇳 · Jin-Biao Gu🇨🇳 · Arpith Kumar🇨🇳 · Sheng-Tai Li🇨🇳

    We present continuum-estimated $(2+1)$-flavor lattice QCD results for the leading-order Taylor expansion coefficients of the equation of state in strong magnetic fields and at nonzero baryon chemical potential. Simulations employ the highly improved staggered quark (HISQ) action with physical pion masses on lattices of temporal extent $N_{\tau }=8,12$, covering $145\lesssim T\lesssim 165\mathrm{MeV}$ and $eB\lesssim 0.8{\mathrm{GeV}}^2$, imposing strangeness neutrality with baseline results at electric charge to baryon number ratio $r=0.4$. We determine the $T$--$eB$ dependence of $q_1$ and $s_1$ (electric charge and strangeness chemical potential ratios), pressure coefficient $P_2$, baryon number density coefficient $N_1^{\mathrm{B}}$, and energy-like coefficients ${\Theta }_2$ (trace anomaly), ${ϵ}_2$ (energy density), and ${\sigma }_2$ (entropy density). Magnetic fields induce temperature-band crossings for $q_1$ and $P_2$ and non-monotonic structures in the energy-like coefficients, with ${\Theta }_2$ at strong fields possibly vanishing or turning negative at higher $T$, indicating dominance of the pressure term over the energy contribution. We also examine the $r$-dependence, finding that $r=0$ (charge-neutral matter) shows the most muted magnetic-field enhancement of $P_2$ despite larger $|q_1|$, providing a useful reference for neutron-star-like conditions. Comparisons with the hadron resonance gas (HRG) model show qualitative agreement at low $T$ and weak $eB$, with clear deviations near the crossover and at strong fields. These results provide useful input for constraining models and effective theories of QCD matter in strong magnetic fields at finite baryon density.

    ↳ hep-lathep-phnucl-thPRD(2025)·10 citations
33. 33*

    Thermo-coalescence model for Light Nuclei production in Relativistic Heavy-Ion Collisions

    Arun Kumar Yadav🇮🇳 · Nachiketa Sarkar🇮🇳 · Sudhir Pandurang Rode🇷🇺 · Partha Pratim Bhaduri🇮🇳 · Abhijit Bhattacharyya🇮🇳 · Amaresh Jaiswal🇮🇳

    We employ a hybrid approach to describe the light nuclei production mechanism where the nucleons are assumed to be thermally produced, and are allowed to form light nuclei using a coalescence prescription. In this approach, we first fit transverse momentum ($p_T$) distribution of nucleons using hydro-inspired boost-invariant blast-wave model. The extracted parameters are then used to describe the deuteron $p_T$ spectra, along with two additional parameters that characterize the coalescence prescription employed in this study. We refer this combined approach as ``thermo-coalescence model'' and it is designed to study the deuteron production and describe the experimental measurements. In this work, we analyze the measured $p_T$ distribution of protons and deuterons from Pb-Pb collisions at the ALICE Collaboration at LHC. We also evaluate the $p_T$-integrated deuteron yields using this approach and compare with experimental measurements. A Bayesian inference framework is employed to determine the best-fit parameters of the thermo-coalescence model. Finally, we estimate the traditionally used experimental coalescence parameter ($B_A$) within our framework in order to establish a connection between our model and the conventional coalescence approach commonly used to relate experimental data with theoretical descriptions of light nuclei production.

    ↳ nucl-thhep-phEPJC(2025)·0 citations
34. 34*

    Topological Strings in SU(3) Gauge Theory at Finite Temperature

    Sanatan Digal🇮🇳 · Vinod Mamale🇮🇳 · Sumit Shaw🇮🇳

    We investigate string configurations in the deconfined phase of SU(3) gauge theory, which arise from the spontaneous breaking of the $Z_3$ center symmetry. These configurations form at the junctions of domain walls of the theory. The complex phase of the Polyakov loop changes by multiples of $2\pi$ on large spatial loops around the string, rendering them topologically stable. Using the Monte Carlo simulations of the partition function, we compute the free energy associated with these configurations. The simulations are performed on lattices with spatial dimensions $N_{x,y}=60,N_z=4$, and temporal extent $N_{\tau }=2$. Our results show that the free energy of the $Z_3-$strings is dominated by the domain walls. Further near the transition point, thermal fluctuations cause the decay of domain walls as well as the $Z_3$ strings into confined-deconfined interfaces.

    ↳ hep-lathep-phhep-thnucl-thPRD(2026)·2 citations
35. 35*

    Thermodynamic and quantum fluctuations of horizon area

    G.E. Volovik🇷🇺

    The event horizon is a source of irreversibility, analogous to statistical irreversibility. This is why for systems with an event horizon there is no difference between quantum and thermal fluctuations. Quantum processes of quantum tunneling determine the thermodynamics of these systems, their temperatures, entropies and fluctuations. We considered three examples of entropy variance that support this point of view: (i) the variance of the area of the black hole horizon, obtained by consideration of quantum fluctuations; (ii) the variance of the entropy of the Hubble volume in the de Sitter state, obtained by consideration of thermal fluctuations; and (iii) the variance of entropy in integers in the Planckon model, determined by the Poisson distribution.

    ↳ gr-qchep-ph2 citations
36. 36*

    Sensitivity of an Early Dark Matter Search using the Electromagnetic Calorimeter as a Target for the Light Dark Matter eXperiment

    LDMX Collaboration · Torsten Åkesson · Elizabeth Berzin · Cameron Bravo · Liam Brennan · Lene Kristian Bryngemark · Pierfrancesco Butti · Filippo Delzanno · E. Craig Dukes · Valentina Dutta · Bertrand Echenard · Ralf Ehrlich and 44 other authors

    The Light Dark Matter eXperiment (LDMX) is proposed to employ a thin tungsten target and a multi-GeV electron beam to carry out a missing momentum search for the production of dark matter candidate particles. We study the sensitivity for a complementary missing-energy-based search using the LDMX Electromagnetic Calorimeter as an active target with a focus on early running. In this context, we construct an event selection from a limited set of variables that projects sensitivity into previously-unexplored regions of light dark matter phase space -- down to an effective dark photon interaction strength $y$ of approximately $2\times 10^{-13}$ ($5\times 10^{-12}$) for a 1MeV (10MeV) dark matter candidate mass.

    ↳ hep-exhep-phphysics.ins-detJHEP(2025)·3 citations
37. 37*

    Coupled Time-Dependent Proton Acceleration and Leptonic-Hadronic Radiation in Turbulent Supermassive Black Hole Coronae

    Chengchao Yuan🇩🇪 · Damiano F. G. Fiorillo🇩🇪 · Maria Petropoulou🇬🇷 · Qinrui Liu🇨🇦

    Turbulent coronae of supermassive black holes can accelerate non-thermal particles to high energies and produce observable radiation, but capturing this process is challenging due to comparable timescales of acceleration, cooling, and the development of cascades. We present a time-dependent numerical framework that self-consistently couples proton acceleration--modeled by the Fokker-Planck equation--with leptonic-hadronic radiation. For the neutrino-emitting Seyfert galaxy NGC 1068, we reproduce the neutrino spectrum observed by IceCube, while satisfying gamma-ray constraints. We also consider a transient corona scenario, potentially emerging in tidal disruption events like AT 2019dsg, and show that cascade feedback on proton cooling can impact proton acceleration and radiation processes in weaker coronae, producing delayed optical/ultraviolet, X-ray, and neutrino emissions of $\mathcal{O}(100\mathrm{d})$. This flexible tool efficiently models multi-messenger signals from both steady and transient astrophysical sources, providing insights in combining particle acceleration and radiation mechanisms.

    ↳ astro-ph.HEastro-ph.COhep-phPRD(2026)·9 citations
38. 38*

    Closing the Mass Window for Stupendously Large Black Holes

    Christopher Gerlach🇩🇪 · Yann Gouttenoire🇩🇪 · Antonio J. Iovino🇦🇪 · Nicholas Leister🇩🇪

    We show that primordial black holes (PBHs) in the $\text{Stupendously Large Black Hole}$ mass range ($M\gtrsim 10^{11}{M}_{\odot }$) produce isocurvature perturbations exceeding current $\text{Planck}$ Cosmic Microwave Background limits, thereby excluding them as a significant dark matter component.

    ↳ astro-ph.COgr-qchep-ph14 citations
39. 39*

    Quantum Gravity and Entanglement in Particle Physics and Gravitation

    Nick E. Mavromatos🇬🇷

    Some approaches to Quantum Gravity (QG) entail decoherence of quantum matter propagating in it, due to an ``environment'' of QG degrees of freedom inaccessible to low-energy observers. In the first part of this talk, I discuss potential, and rather unique, effects of QG-induced decoherence on entangled particle states, specifically an induced modification of Einstein-Podolsky-Rosen (EPR) correlations of entangled neutral-meson states in meson factories ($\omega$-effect). In the second part, I summarise a recent work in which axion-like fields, forming a kind of condensate clouds surrounding rotating (Kerr-type) astrophysical black holes, can lead to superradiant instabilities, and, through these, to the production of EPR-like entangled states of gravitons, with the entanglement pertaining to (left, right) polarisation degrees of freedom. In the presence of axions and Kerr geometries, there are non-trivial gravitational Chern-Simons (gCS)-type anomalous terms in the respective low-energy gravitational effective actions. Depending on whether the graviton entanglement is due to the non-anomalous terms (of General-Relativity type) in the effective action, or to the gCS terms, one obtains different structures of the resulting entangled squeezed-graviton states, which resemble somewhat the $\omega$-effect.

    ↳ gr-qchep-phhep-thInt.J.Mod.Phys.A(2026)·0 citations
40. 40*

    A Compact Story of Positivity in de Sitter

    Priyesh Chakraborty🇺🇸 · Timothy Cohen🇨🇭 · Daniel Green🇺🇸 · Yiwen Huang🇺🇸

    Recent developments have yielded significant progress towards systematically understanding loop corrections to de Sitter (dS) correlators. In close analogy with physics in Anti-de Sitter (AdS), large logarithms can result from loops that can be interpreted as corrections to the dimensions of operators. In contrast with AdS, these dimensions are not manifestly real. This implies that the theoretical constraints on the associated correlators are less transparent, particularly in the presence of light scalars. In this paper, we revisit these issues by performing and comparing calculations using the spectral representation approach and the Soft de Sitter Effective Theory (SdSET). We review the general arguments that yield positivity constraints on dS correlators from both perspectives. Our particular focus will be on vertex operators for compact scalar fields, since this case introduces novel complications. We will explain how to resolve apparent disagreements between different techniques for calculating the anomalous dimensions for principal series fields coupled to these vertex operators. Along the way, we will offer new proofs of positivity of the anomalous dimensions, and explain why renormalization group flow associated with these anomalous dimensions in SdSET is the same as resumming bubble diagrams in the spectral representation.

    ↳ hep-thastro-ph.COhep-phJHEP(2026)·12 citations
41. 41*

    Self-Gravity in Superradiance Clouds: Implications for Binary Dynamics and Observational Prospects

    Hyungjin Kim🇩🇪 · Alessandro Lenoci🇮🇱

    Spinning black holes could produce ultralight particles via the superradiance instability. These particles form a dense cloud around the host black hole, introducing new opportunities for the detection of ultralight new physics. When the black hole is part of a binary system, the binary can trigger transitions among different states of the cloud configuration. Such transitions backreact on the orbital dynamics, modifying the frequency evolution of the emitted gravitational waves. Based on this observation, black hole binaries were proposed as a way to test the existence of ultralight particles. We investigate the effects of the self-gravity of the cloud on the orbital evolution and on the gravitational wave emission. We find that cloud self-gravity could lead to a density-dependent modification of the energy levels of ultralight particles and that it could alter the order of hyperfine energy levels. The crossing of hyperfine levels prevents binaries from triggering resonant hyperfine transitions and allows them to approach radii that could trigger resonant transitions of fine levels. We study the implications of these findings, especially in the context of future space-borne gravitational wave observatory, the Laser Interferometer Space Antenna (LISA). For quasi-circular, prograde and equatorial orbits, we find that LISA could probe ultralight particles in the mass range $10^{-15}\mathrm{eV}-10^{-13}\mathrm{eV}$ through gravitational wave observations.

    ↳ gr-qchep-phhep-thPRD(2025)·10 citations
42. 42*

    Generation of High Order Harmonics in Vacuum for Various Configurations of Interacting Electromagnetic Field

    Pavel Sasorov🇨🇿 · Sergei Bulanov🇨🇿

    High order harmonic (HOH) generation by interacting extremely intense electromagnetic waves in the quantum vacuum is investigated within the framework of the Heisenberg-Euler formalism. We consider here the process in the lowest order of a perturbation theory relative to the electromagnetic (EM) beam intensity, giving contribution to the HOH generation. The main expressions are obtained for a general geometry, whyle polarizations of different sub-beams forming the EM beam focus are almost the same. Nevertheless, explicit expressions for the HOH generation are derived for the $4\pi$-dipole in-coming waves and for the two crossing Gaussian beams. The former geometry of the EM beam is optimal at a given EM wave power, whereas the latter one is more realistic from the experimental point of view. We consider also a relationship of our present general results with the results, obtained earlier for the HOH generation during of collision of two plane electromagnetic waves.

    ↳ physics.plasm-phhep-phNew J.Phys.(2026)·2 citations
43. 43*

    Jet Image Tagging Using Deep Learning: An Ensemble Model

    Juvenal Bassa🇺🇸 · Vidya Manian🇺🇸 · Sudhir Malik🇺🇸 · Arghya Chattopadhyay🇺🇸

    Jet classification in high-energy particle physics is important for understanding fundamental interactions and probing phenomena beyond the Standard Model. Jets originate from the fragmentation and hadronization of quarks and gluons, and pose a challenge for identification due to their complex, multidimensional structure. Traditional classification methods often fall short in capturing these intricacies, necessitating advanced machine learning approaches. In this paper, we employ two neural networks simultaneously as an ensemble to tag various jet types. We convert the jet data to two-dimensional histograms instead of representing them as points in a higher-dimensional space. Specifically, this ensemble approach, hereafter referred to as Ensemble Model, is used to tag jets into classes from the JetNet dataset, corresponding to: Top Quarks, Light Quarks (up or down), and W and Z bosons. For the jet classes mentioned above, we show that the Ensemble Model can be used for both binary and multi-categorical classification. This ensemble approach learns jet features by leveraging the strengths of each constituent network achieving superior performance compared to either individual network.

    ↳ physics.data-ancs.AIcs.LGhep-ex+1JINST(2025)·1 citation

* 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.