Tue·Dec 31, 2024Tuesday·December 31, 2024

1. 01*

   Search for sub-GeV Scalars in $e^{+}{e}^{-}$ collisions

   D. Cogollo🇧🇷 · Y.M. Oviedo-Torres🇨🇱 · Farinaldo S. Queiroz🇧🇷 · Yoxara Villamizar🇧🇷 · J. Zamora-Saa🇨🇱

   Light scalars that couple to leptons are common figures in beyond the Standard Model endeavors. Considering a scalar that has universal and couplings to leptons only, we compute this leptophilic scalar contribution to the $e^{-}{e}^{+}\to {\tau }^{+}{\tau }^{-}S$ production cross section with $S\to e^{+}{e}^{-}({\mu }^{+}{\mu }^{-})$. We later compare the expected signal with recent data from the BELLE collaboration collected near the resonance ${\rm Y}(4S)$ with $\mathcal{L}=626f{b}^{-1}$ of integrated luminosity to place limits on the couplings-mass plane for the $4$~MeV-$6.5$~GeV mass range. We then extended this analysis to a more general one $e^{-}{e}^{+}\to {\ell }^{+}{\ell }^{-}S$ production cross section where $\ell =e,\mu ,\tau$ with $S\to e^{+}{e}^{-}({\mu }^{+}{\mu }^{-})$, showing that BELLE constitutes an excellent laboratory for light scalars, where can be derived constraints stronger than those derived stemming from the g-2 of the electron or muon.

   hep-phhep-thEPJC(2025)·4 citations
2. 02*

   Strong-Weak Bi-Adjoints, Gluon-W resonances, and new asymmetric LHC production processes

   Linda M. Carpenter🇺🇸 · Katherine Schwind🇺🇸

   We study a novel production and decay mechanism for a bi-adjoint spin zero particle in the ($8,3,0$) representation of the Standard Model gauge groups. This work is part of a series studying new production processes for exotic particles in higher representations of Standard Model color and weak charge. Here, we study a specific new dimension 5 effective operator model which couples an exotic bi-adjoint scalar field to the SU(3) and SU(2) field strength tensors. The W-gluon resonant decay of the charged component of this new exotic field is explored. We discuss LHC production modes of both the charged and neutral bi-adjoint states and find a new single production mode for the charged state. This is the dominant LHC production mode for TeV-scale masses. We introduce a new HL-LHC search in which a single bi-adjoint is produced in association with a hard forward quark jet from asymmetric W-gluon fusion. This search yields a 5-sigma discovery potential for bi-adjoint masses up to 3 TeV for 10 TeV scalar effective operator cutoffs. We also find 2-sigma sensitivity at the HL-LHC for bi-adjoint masses up to 4 TeV and effective cutoffs in the 15 TeV range for the full 3 inverse atto-barn data set.

   hep-phPRD(2026)·3 citations
3. 03*

   Pion fragmentation functions from a quark-jet model in a functional approach

   Roberto Correa da Silveira🇧🇷 · Fernando E. Serna🇨🇴 · Bruno El-Bennich🇧🇷

   The elementary fragmentation function that describes the process $q\to \pi$ is predicted applying crossing and charge symmetry to the cut diagram of the pion valence quark distribution function. This elementary probability distribution defines the ladder-kernel of a quark jet fragmentation equation, which is solved self-consistently to obtain the full pion fragmentation function. The hadronization into a pion employs the complete Poincaré invariant Bethe-Salpeter wave function, though the overwhelming contribution to the fragmentation function is due the leading Bethe-Salpeter amplitude. Compared to a Nambu--Jona-Lasinio model prediction, the fragmentation function we obtain is enhanced in the range $z\lesssim 0.8$ but otherwise in good qualitative agreement. The full pion fragmentation function is overall greater than the elementary fragmentation function below $z\lesssim 0.6$.

   hep-phhep-exnucl-exnucl-thPRC(2025)·3 citations
4. 04*

   Gauge covariance of the gap equation: from the rainbow truncation to gauge symmetry constraints

   Bruno El-Bennich🇧🇷

   The gauge covariance of the quark gap equation is compared for three quark-gluon vertices: the bare vertex, a Ball-Chiu like vertex constrained by the corresponding Slavnov-Taylor identity, and a full vertex including the transverse components derived from transverse Slavnov-Taylor identities. The covariance properties are verified with the chiral quark condensate and the pion decay constant in the chiral limit.

   hep-phhep-latnucl-thSymmetry(2025)·1 citation
5. 05*

   The nucleon properties in finite temperature and density with vector meson

   Bingtao Li🇨🇳 · Yiming Lyu🇨🇳 · Song Shu🇨🇳 · PeiXin Weng🇨🇳 · Hui Zhang🇨🇳

   We introduce the vector meson $\omega$ into the Quark Meson model, and study the impact of vector interactions on the properties of static hadrons using the mean-field approximation. The short-range repulsive force associated with vector interactions leads to an expansion of the root mean square radius of nucleons. While the mass of hadrons increases, the gap between this mass and the energy of the three free constituent quarks decreases, resulting in the instability of hadrons. Our study of nucleon mass and radius at finite temperature and density has potential applications for particle yield in heavy ion collisions and the mass-radius relationship in compact stars.

   hep-phhep-thnucl-th2 citations
6. 06*

   Revisiting CMSSM with Non-Universal Gaugino Masses under Current Constraints

   Yabo Dong🇨🇳 · Kun Wang🇨🇳 · Hailong Yuan🇨🇳 · Jingya Zhu🇨🇳 · Pengxuan Zhu

   To address the longstanding tension between the Constrained Minimal Supersymmetric Standard Model (CMSSM) and recent experimental data, we investigate non-universal gaugino masses within an SU(5) Grand Unified Theory (GUT) framework, focusing on the $\tilde{g}$-SUGRA scenario where $|M_3|\gg |M_1|,|M_2|$. This hierarchy enables a heavier gluino, thereby evading current experimental bounds on supersymmetric particles. Our analysis reveals that precise Higgs measurements place stringent constraints on the model, requiring $\tan \beta \gtrsim 5$ and $M_0\gtrsim 20\tan \beta \text{GeV}$. Although the $\tilde{g}$-SUGRA scenario can help reconcile the persistent $(g-2{)}_{\mu }$ anomaly, the Higgs constraints significantly restrict its parameter space, making a large contribution to $(g-2{)}_{\mu }$ challenging. We also assess the discovery prospects in upcoming dark matter direct detection experiments, including PandaX-xT (200 t.y.), LZ (projected), and XENONnT (20 t.y.), which may not fully cover the viable parameter space. In contrast, future collider experiments$-$such as the High-Luminosity LHC at $3{\mathrm{ab}}^{-1}$ and ${\mathrm{CLIC}}_{1500}$ at $2.5{\mathrm{ab}}^{-1}$$-$can comprehensively probe the remaining regions. These findings highlight $\tilde{g}$-SUGRA as a promising solution to the CMSSM tension and offer clear, testable predictions for upcoming collider searches.

   hep-phhep-exJHEP(2025)·2 citations
7. 07*

   Neutrino mass ordering sensitivities at DUNE, HK and KNO in presence of scalar NSI

   Moon Moon Devi🇮🇳 · Dharitree Bezboruah🇮🇳 · Abinash Medhi🇮🇳 · Arnab Sarker🇮🇳 · Debajyoti Dutta🇮🇳

   The limitations of the Standard Model in explaining neutrino masses and neutrino mixing lead to the exploration of frameworks beyond the Standard Model (BSM). The possibility of neutrinos interacting with fermions via a scalar mediator is one of the interesting prospects. The study of neutrino non-standard interactions (NSI) is a well-motivated phenomenological scenario to explore new physics beyond the Standard Model. These new interactions may alter the standard neutrino oscillation probabilities, potentially leading to observable effects in experiments. It also allows for the exploration of absolute neutrino masses via oscillation experiments. It can modify the oscillation probabilities, which in turn can affect the physics sensitivities in long-baseline experiments. The linear scaling of the effects of scalar NSI with matter density also motivates its exploration in long-baseline (LBL) experiments. We will present our study on the impact of a scalar-mediated NSI on the mass ordering (MO) sensitivities of three long-baseline neutrino experiments, i.e., DUNE, HK and KNO. We study the impact on MO sensitivities at these experiments assuming that scalar NSI parameters are present in nature and are known from other non-LBL experiments. The presence of scalar NSI can notably impact the MO sensitivities of these experiments. Furthermore, we analyze the potential synergy by combining data from DUNE with HK and HK+KNO, thereby exploring a broader parameter space.

   hep-ph0 citations
8. 08*

   Dark Photons and Gravitino Like Particles: Complete EFT Operator Basis

   Ziyu Dong🇪🇸 · Teng Ma🇨🇳 · Chengjie Yang🇨🇳 · Zizheng Zhou🇨🇳

   We present a more efficient method for constructing the complete EFT operator basis for particles of any mass and spin, based on on-shell method and Young tableaux. By classifying the amplitude bases according to the polarization configurations of massive particles and using their high-energy limit, our approach can construct EFT basis in a straightforward way, without need of auxiliary fields and tedious basis decomposition. Based on this improved method, we develop a Mathematica code that can automatically construct the EFT basis for particles of any spin. As applications, the EFT bases up to d=8 are explicitly constructed for dark photons and, for the first time, for spin-3/2 gravitino like particles.

   hep-phhep-thJHEP(2025)·4 citations
9. 09*

   The Spectra of $p\bar{\Lambda }$ and $p\bar{\Sigma }$ Hexaquark States

   Xuan-Heng Zhang🇨🇳 · Sheng-Qi Zhang🇨🇳 · Cong-Feng Qiao🇨🇳

   Motivated by the observation of the $J^P=1^{+}$ resonance $X(2085)$ in the $p\bar{\Lambda }$ system by the BESIII collaboration, we studied the molecular states of hexaquarks $p\bar{\Lambda }$ and $p\bar{\Sigma }$ with baryon-antibaryon structures within the framework of the QCD sum rules. Non-perturbative contributions up to dimension 13 were considered in our analysis. The results indicate the existence of six possible molecular states $p\bar{\Lambda }$ and $p\bar{\Sigma }$, with quantum numbers $J^P=0^{-},0^{+},1^{-}$. Consequently, the current sum rule results do not support the interpretation of $X(2085)$ as a $p\bar{\Lambda }$ or $p\bar{\Sigma }$ molecular state. On the other hand, we find that the masses of the proposed $p\bar{\Lambda }$ and $p\bar{\Sigma }$ structures with $J^P=1^{-}$ are in the vicinity of observed $X(2075)$, which implies that the nature of this state needs more invistigations. Moreover, the possible decay modes of the concerned hexaquark states are analyzed.

   hep-phhep-exnucl-thEPJC(2025)·11 citations
10. 10*

    Single Higgs boson production in association with a top quark through FCNSI

    V. M. López-Guerrero🇲🇽 · M. A. Arroyo-Ureña🇲🇽 · J. L. Díaz-Cruz🇲🇽 · O. Félix-Beltrán🇲🇽 · T. A. Valencia-Pérez🇲🇽

    We study the production and possible detection of a single Higgs boson in association with a top quark in proton-proton collisions ($pp\to th+X$) at the High-Luminosity Large Hadron Collider. This process absent in the Standard Model is predicted by other models such as the Two-Higgs Doublet Model of type III, which is the theoretical framework adopted in this work. Promising results are found for specific scenarios of the model parameter space, which consist mainly of the parameters $\tan \beta$, $\cos (\alpha -\beta )$ and the parameter ${\chi }_{tc}$, responsible for the Flavor-Changing Neutral Scalar Interactions (FCNSI). Using the machine learning \textit{Boosted Decision Trees} algorithm and considering a systematic uncertainty of $5\%$, we predict \textit{signal significances} at level of $5\sigma$ for $\tan \beta =1$, $\cos (\alpha -\beta )=0.1$, ${\chi }_{tc}=5$, and integrated luminosities {${\mathcal{L}}_{\mathrm{int}}\gtrsim 2700f{b}^{-1}$}. Likewise, we also predict a \textit{signal significance} $\sigma \approx 4.4$ for $\tan \beta =1$, $\cos (\alpha -\beta )=0.1$, ${\chi }_{tc}=3$, and integrated luminosities ${\mathcal{L}}_{\mathrm{int}}=3000f{b}^{-1}$, which consider the upper limit given by HL-LHC projection on $\mathcal{B}\mathcal{R}(t\to ch)$.

    hep-phPLB(2025)·0 citations
11. 11*

    Top-quark pole mass extraction at NNLO accuracy

    S. Alekhin🇩🇪 · M.V. Garzelli🇩🇪 · J. Mazzitelli🇨🇭 · S.-O. Moch🇩🇪 · O. Zenaiev🇩🇪

    We describe our recent NNLO QCD extraction of the top-quark pole mass from fits to experimental data on total inclusive and normalized (multi)-differential cross sections for $t\bar{t}+X$ hadroproduction, using as input various modern PDF + ${\alpha }_s(M_Z)$ sets. We find top-quark mass values compatible among each other and with the PDG 2024 preferred value.

    hep-phPoS(2025)·0 citations
12. 12*

    Thomas precession, relativistic torque, and non-planar orbits

    Andrzej Czarnecki🇨🇦 · Andrei Zelnikov🇨🇦

    We analyze the angular momentum balance for a particle undergoing Thomas precession. The relationships among relativistic torque, the center of mass, and the center of inertia for a spinning particle are clarified. We show that spin precession is accompanied by orbital angular momentum precession, and present examples of the resulting out-of-plane motion.

    hep-phhep-thEPJC(2025)·0 citations
13. 13*

    The role of the $f_0(1710)$ and $a_0(1710)$ resonances in the $D^0\to {\rho }^0\varphi$, $\omega \varphi$ decays

    Natsumi Ikeno🇯🇵 · Wen-Hao Jia🇨🇳 · Wei-Hong Liang🇨🇳 · Eulogio Oset🇪🇸

    We study the $D^0\to {\rho }^0\varphi$, $\omega \varphi$ decays which proceed in a direct mode via internal emission with equal rates. Yet, the experimental branching ratio for the ${\rho }^0\varphi$ mode is twice as big as that for the $\omega \varphi$ mode. We find a natural explanation based on the extra indirect mechanism where $K^{\ast +}{K}^{\ast -}$ is produced via external emission and that channel undergoes final state interaction with other vector--vector channels to lead to the ${\rho }^0\varphi$, $\omega \varphi$ final states, with transition amplitudes dominated by the $a_0(1710)$ resonance, recently discovered, and $f_0(1710)$ respectively. The large coupling of the $a_0(1710)$ to the ${\rho }^0\varphi$ channel is mostly responsible for this large ratio of the production rates.

    hep-phEPJA(2025)·1 citation
14. 14*

    Final-state rescattering mechanism in bottom-baryon decays

    Zhu-Ding Duan🇨🇳 · Jian-Peng Wang🇨🇳 · Run-Hui Li🇨🇳 · Cai-Dian Lv · Fu-Sheng Yu🇨🇳

    The first observation of $CP$ violation in baryon decays was recently reported by the LHCb collaboration in ${\Lambda }_b^0\to p{K}^{-}{\pi }^{+}{\pi }^{-}$ with $A_{CP}=(2.45\pm 0.46\pm 0.10)\%$, which inspires the study on baryon non-leptonic decays. In this work, we perform the first calculation of five exclusive non-leptonic decays, ${\Lambda }_b^0\to p{\pi }^{-},p{K}^{-},p{\rho }^{-},p{K}^{\ast -}$ and $\Lambda \varphi$, within the re-scattering approach. The triangle diagrams at hadron level are calculated in form of loop integrations. It leads to the generation of strong phases, which is essential to the calculation of $CP$ asymmetries. We present numerical results for branching ratios, direct and partial-wave $CP$ asymmetries, decay asymmetry parameters and their associated $CP$ asymmetries. Our results are consistent with the current LHCb experimental data, which indicates the validity and potential of our approach in studying the $CP$ asymmetries of $b$-baryon decays. Most of our results are expected to be tested in future experiments.

    hep-phJHEP(2025)·18 citations
15. 15*

    Parity Violation on Longitudinal Single-Spin Asymmetries at the EicC

    Yong Du🇨🇳

    We explore two longitudinal single-spin asymmetries induced from parity violation in neutral-current deep inelastic scattering at the proposed Electron-ion collider in China (EicC): $A_{PV}^{e(p)}$ from longitudinally polarized (unpolarized) electrons scattering off unpolarized (longitudinally polarized) protons. We find $A_{PV}^e$, of $\mathcal{O}(10^{-4})$, is generically one to three orders of magnitude larger than $A_{PV}^p$. We further estimate different uncertainty sources including statistics, parton distribution functions, and beam polarization, for both asymmetries, and then identify individually their dominance in different regimes of the Bjorken-$x$. Based on these results, we then advocate utilizing $A_{PV}^p$ for the extraction of the weak mixing angle at two representative momentum transfer scales unexplored before, and we find a relative precision below 10% can be achieved at the EicC with an effective one-year operation time.

    hep-phhep-exPRD(2025)·6 citations
16. 16*

    Flavour-Dependent Chemical Freeze-Out of Light Nuclei in Relativistic Heavy-Ion Collisions

    Rishabh Sharma🇮🇳 · Fernando Antonio Flor🇺🇸 · Sibaram Behera🇮🇳 · Chitrasen Jena🇮🇳 · Helen Caines🇺🇸

    We study the production of light nuclei in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}$ = 7.7 - 200 GeV and Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 and 5.02 TeV within a flavour-dependent freeze-out framework, assuming different flavoured hadrons undergo separate chemical freeze-out. Using the Thermal-FIST package, thermal parameters extracted from fits to various sets of hadron yields, including and excluding light nuclei, are used to calculate the ratios of the yields of light nuclei, namely, $d/p$, $\bar{d}/\bar{p}$, $t/p$, and $t/d$. A comparison with data from the STAR and ALICE collaborations shows that a sequential freeze-out scenario provides a better description of light nuclei yield ratios than the traditional single freeze-out approach. These results suggest the flavour-dependent chemical freeze-out for final state light-nuclei production persists in heavy-ion collisions at both RHIC and LHC energies.

    hep-phhep-exnucl-thEPJC(2025)·2 citations
17. 17*

    Resonances all over the place?

    Anirban Kundu (Department of Physics, University of Calcutta)🇮🇳 · Poulami Mondal (Department of Physics, Indian Institute of Technology Kanpur)🇮🇳 · Gilbert Moultaka (Laboratoire Univers & Particules de Montpellier, CNRS & Montpellier Univ.)🇫🇷

    We provide a possible interpretation of excesses reported by ATLAS and CMS at around 95GeV, 650GeV and possibly 320GeV, in terms of CP-even scalars. In particular, the combined {\sl global} statistical significances of independent indications for a 650GeV object reach the $4\sigma$ level! While this seems sufficient incentive for a further investigation, this object cannot be fitted in tradional singlet or doublet extensions of the Standard Model. It requires by itself a larger extension with doubly-charged scalars, that naturally fits the two other excesses on top of the SM-like 125~GeV Higgs. We describe the minimal model and give some numerical illustrations.

    hep-phhep-ex1 citation
18. 18*

    Regge poles and cuts and the Lipatov vertex

    Samuel Abreu🇬🇧 · Giulio Falcioni🇮🇹 · Einan Gardi🇬🇧 · Calum Milloy🇨🇭 · Leonardo Vernazza🇮🇹

    Scattering amplitudes in the high-energy limit can be described in terms of their singularity structure in the complex angular momentum plane, consisting of Regge poles and cuts. In QCD, gluon Reggeization has long been understood as a manifestation of a Regge pole, but until recently Reggeization violation remained largely obscure. New methods, based on iterative solution of rapidity evolution equations, facilitate direct computation of components of the amplitude which are mediated by multi-Reggeon exchange, a manifestation of Regge cuts. Upon disentangling the Regge cut from the pole we are now able to extract the pole parameters from state-of-the-art fixed-order computations (3 loops) and make predictions regarding certain components of the amplitude to higher loop orders. In this talk I review the key ideas which led to this progress, describe where we stand in exploring the structure of 2 -> 2 and 2 -> 3 amplitudes in the (multi-) Regge limit, and comment on the interplay between this research and the study of infrared factorization.

    hep-phPoS(2024)·6 citations
19. 19*

    The Two-Loop Lipatov Vertex in QCD

    Samuel Abreu🇨🇭 · Giuseppe De Laurentis🇬🇧 · Giulio Falcioni🇮🇹 · Einan Gardi🇬🇧 · Calum Milloy🇮🇹 · Leonardo Vernazza🇮🇹

    High-energy factorization of 2 -> 2 amplitudes in QCD has been recently pushed to the next-to-next-to-leading logarithmic order by determining the three-loop gluon Regge trajectory. This was based on computing multi-Reggeon exchanges using rapidity evolution in the shock-wave formalism, and disentangling between the Regge pole and Regge cut contributions. In the present paper we extend the relevant theoretical framework to 2 -> 3 processes, and compute all multi-Reggeon exchanges necessary for extracting the two-loop Reggeon-gluon-Reggeon Lipatov vertex from 2 -> 3 amplitudes. Then, specializing general amplitude methods to multi-Regge kinematics, we derive analytic expressions for non-planar two-loop gg -> ggg, gq -> ggq and qq -> qgq QCD amplitudes in that limit. Matching these to the multi-Reggeon computation, we determine the QCD Lipatov vertex in dimensional regularization at two loops through finite terms. We also determine the one-loop vertex through O(epsilon^4). All results are expressed in a compact form in terms of a basis of single-valued generalised polylogarithms, manifesting target-projectile symmetry and reality properties. Furthermore, our basis of functions is explicitly finite in the soft limit, featuring delicate cancellation of spurious rational poles by transcendental functions. Agreement between all three partonic channels, as well agreement of the maximal weight contributions with the super Yang-Mills Lipatov vertex provide robust checks of the result.

    hep-phhep-thJHEP(2025)·18 citations
20. 20*

    Refining lower bounds on sterile neutrino dark matter mass from estimates of phase space densities in dwarf galaxies

    Fedor Bezrukov🇨🇭 · Dmitry Gorbunov🇷🇺 · Ekaterina Koreshkova🇷🇺

    Dwarf spheroidal galaxies (dSphs) are recognized as being highly dominated by Dark Matter (DM), making them excellent targets for testing DM models through astrophysical observations. One effective method involves estimating the coarse-grained phase-space density (PSD) of the galactic DM component. By comparing this PSD with that of DM particles produced in the early Universe, it is possible to establish lower bounds on the DM particle mass. These constraints are particularly relevant for models of warm DM, such as those involving sterile neutrinos. Utilizing the GravSphere code, we obtain a fit of the DM PSD based on the latest reliable stellar dynamics data for twenty of the darkest dSphs, refining earlier lower bounds on sterile neutrino masses in non-resonant production scenarios. Additionally, we introduce an alternative approach involving the Excess Mass Function (EMF), which yields even tighter constraints. Specifically, using the maximum PSD, we derive a lower bound of $m>1.02$keV at 95% confidence level, while the EMF method provides a stronger limit of $m>1.98$keV at 95% CL. For the general thermal relic fermion dark matter mass the limits translate into $m>0.28$keV and $m>0.49$keV, respectively. Both methods are versatile and can be extended to more complex DM production mechanisms in the early Universe. For the first time, we also constrain parameters of models involving non-standard cosmologies during the epoch of neutrino production. Our analysis yields $m>2.54$keV for models with kination domination and $m>4.71$keV for scenarios with extremely low reheating temperature.

    hep-phastro-ph.COastro-ph.GAInt.J.Mod.Phys.A(2025)·12 citations
21. 21*

    The quark-lepton portal beyond leptoquarks

    Linda M. Carpenter🇺🇸 · Katherine Schwind🇺🇸 · Taylor Murphy🇺🇸

    We explore models where single new exotic states interact with the Standard Model through an asymmetric Standard Model portal with couplings to at least one quark and one lepton. All effective operators up to dimension six where such interactions couple the SM to spin 0 and spin 1/2 particles are written down, and the exotic states accessible through the portal are identified. We note interactions that couple the SM to new particles with exotic combinations of baryon and lepton numbers, states of higher electric charge, and particles with unusual SM charge, including states in higher-dimensional representations of both SU(3) and SU(2). Finally, we discuss the phenomenology of these interactions, including novel particle decays, and we classify some of the collider production modes for exotic states at the LHC, LHeC and muon colliders.

    hep-phEPJC(2026)·2 citations
22. 22*

    Pathways to proton's stability via naturally small neutrino masses

    Sin Kyu Kang🇰🇷 · Oleg Popov🇨🇳

    In the present work, the connection between the smallness of the neutrino masses and the stability of the proton is studied. We analyze this connection from different perspectives: the smallness of neutrino mass and the proton stability originate from the same source, small neutrino masses lead to a long lived proton, and the smallness of the proton decay width as a cause of the naturally small neutrino masses. All the schemes are studied in detail and UV realizations are given. We discuss advantages of each scheme and outline further investigation directions.

    hep-phhep-exhep-lat2 citations
23. 23*

    Possible scenario of dynamical chiral symmetry breaking in the instanton liquid

    Yamato Suda🇯🇵 · Daisuke Jido🇯🇵

    Based on simulations of the interacting instanton liquid model (IILM) with three-flavor quarks, we compute the free energy density of the QCD vacuum as a function of the quark condensate. We then evaluate the second derivative of the free energy density with respect to the quark condensate at the origin. This evaluation allows us to investigate whether chiral symmetry breaking in the IILM occurs in an anomaly-driven way. Such a breaking pattern of chiral symmetry has been proposed in a previous study to connect the QCD vacuum structure with meson properties, such as the mass of the sigma meson. We also perform the quenched simulations, in which no dynamical quarks interact with instantons. Comparing these results with the full calculations provides a better understanding of the pattern of chiral symmetry breaking in the IILM. We find that in the full IILM, chiral symmetry is dynamically broken in anomaly-driven way, whereas in the quenched IILM, it is broken through the ordinary mechanism. Based on these results, we suggest that chiral symmetry breaking in real QCD could also occur in an anomaly-driven way. Consequently, in phenomena where chiral symmetry breaking plays a crucial role, the anomaly effect may also have significant influence.

    hep-phnucl-thPoS(2025)·0 citations
24. 24*

    Emergence, Formation and Dynamics of Hot QCD Matter

    Bruno Sebastian Scheihing-Hitschfeld🇺🇸

    In this thesis, we make progress in two concrete directions in the vast landscape of hot QCD physics. The first one is quarkonium transport inside quark-gluon plasma (QGP), the high temperature phase of QCD. Over the past two decades it has been realized that a significant fraction of quarkonium suppression in high energy heavy ion collisions comes from dynamic dissociation and recombination processes, instead of static screening of the interaction potential as originally proposed by Matsui and Satz. Our contribution is the formulation of the precise correlation functions in QCD at finite temperature that describe the dissociation and recombination processes of heavy quarkonium in QGP, as well as their calculation in weakly coupled QCD and strongly coupled $\mathcal{N}=4$ supersymmetric Yang-Mills theory. We also formulate the Euclidean version of these correlation functions so that they may be calculated using Lattice QCD techniques. The second contribution we make is the development of tools to understand the process of hydrodynamization in QCD kinetic theory and their application to a simplified description where only a subset of the QCD scattering mechanisms are included. By doing this, we learn that the process of hydrodynamization in this theory, and specifically, how memory of the initial condition is lost, follows the recently proposed Adiabatic Hydrodynamization scenario. Concretely, hydrodynamization proceeds through a sequential process in which a monotonously shrinking set of low-energy states dominate the dynamics, where the opening of an energy gap relative to the ground state(s) signals the start of each stage of this process. The hydrodynamic attractor is reached when only one low-energy state remains as the ground state, and the system approaches local thermal equilibrium following the adiabatic evolution of this low-energy state.

    hep-phhep-thnucl-th2 citations
25. 25*

    Probing Long-Range Forces Between Neutrinos with Cosmic Structures

    David E. Kaplan🇺🇸 · Xuheng Luo🇺🇸 · Surjeet Rajendran🇺🇸

    We study the consequences of new long-range forces between neutrinos on cosmic scales. If these forces are a few orders of magnitude stronger than gravity, they can induce perturbation instability in the non-relativistic cosmic neutrino background in the late time universe. As a result, the cosmic neutrino background may form nonlinear bound states instead of free-streaming. The implications of the formation of nonlinear neutrino bound states include enhancing matter perturbations and triggering star formation. Based on existing measurements of the matter power spectrum and reionization history, we place new constraints on long-range forces between neutrinos with ranges lying in $1\text{ kpc}\lesssim m_{\varphi }^{-1}\lesssim 10\text{ Mpc}$.

    hep-phastro-ph.COPRD(2025)·11 citations
26. 26*

    Baryon number violating hydrogen decay

    Wei-Qi Fan🇨🇳 · Yi Liao🇨🇳 · Xiao-Dong Ma🇨🇳 · Hao-Lin Wang🇨🇳

    Most studies on baryon number violating (BNV) processes in the literature focus on free or bound nucleons in nuclei, with limited attention given to the decay of bound atoms. Given that hydrogen is the most abundant atom in the universe, it is particularly intriguing to investigate the decay of hydrogen atom as a means to probe BNV interactions. In this study, for the first time, we employ a robust effective field theory (EFT) approach to estimate the decay widths of two-body decays of hydrogen atom into standard model particles, by utilizing the constraints on the EFT cutoff scale derived from conventional nucleon decay processes. We integrate low energy effective field theory (LEFT), chiral perturbation theory (ChPT), and standard model effective field theory (SMEFT) to formulate the decay widths in terms of the LEFT and SMEFT Wilson coefficients (WCs), respectively. By applying the bounds on the WCs from conventional nucleon decays, we provide a conservative estimate on hydrogen BNV decays. Our findings indicate that the bounds on the inverse partial widths of all dominant two-body decays exceed $10^{44}$ years. Among these modes, the least constrained diphoton decay $\text{Hy}\to \gamma \gamma$ might be astrophysically interesting, although the monochromatic photon signal from our Sun is difficult to detect with current near-Earth telescopes.

    hep-phPLB(2025)·11 citations
27. 27*

    Probing Sub-eV Dark Photon, Scalar and Axion-like Particle Dark Matters with Transmon Qubits

    Wei Chao🇨🇳 · Yu Gao🇨🇳 · Ming-jie Jin🇨🇳 · Xiao-sheng Liu🇨🇳 · Xi-lei Sun🇨🇳

    In this paper, we investigate constraints of the transmon qubit, an improved version of the charge qubit, on bosonic light dark matters. Phonon excitations induced by the scattering or absorption of dark matter on a superconductor may destroy the Cooper pair, leading to the production of quasiparticles made by the electron. By measuring the production rate of the quasiparticle density, one may read out the coupling between dark matter and ordinary matter, assuming that these quasiparticles are solely induced by dark matter interactions. For the first time, we show constraints on the parameter space of the dark photon, light scalar dark matter, and axion-like particles from the measurement of quasiparticles in transmon qubit experiments. This study offers insights for the development of quantum qubit experiments aimed at the direct detection of dark matter in underground laboratories.

    hep-phquant-phPhys.Dark Univ.(2025)·7 citations
28. 28*

    Femtoscopic study of the $S=-1$ meson-baryon interaction: $K^{-}p$, ${\pi }^{-}\Lambda$ and $K^{+}{\Xi }^{-}$ correlations

    P. Encarnación🇪🇸 · A. Feijoo🇪🇸 · V. Mantovani Sarti🇩🇪 · A. Ramos🇪🇸

    We study the femtoscopic correlation functions of meson-baryon pairs in the strangeness $S=-1$ sector, employing unitarized s-wave scattering amplitudes derived from the chiral Lagrangian up to next-to-leading order. For the first time, we deliver predictions on the ${\pi }^{-}\Lambda$ and $K^{+}{\Xi }^{-}$ correlation functions which are feasible to be measured at the Large Hadron Collider. We also demonstrate that the employed model is perfectly capable of reproducing the $K^{-}p$ correlation function data measured by the same collaboration, without the need to modify the coupling strength to the ${\bar{K}}^{0}n$ channel, as has been recently suggested. In all cases, the effects of the source size on the correlation are tested. In addition, we present detailed analysis of the different coupled-channel contributions, together with the quantification of the relative relevance of the different terms in the interaction. These calculations require the knowledge of the so-called production weights, for which we present two novel methods to compute them.

    hep-phnucl-thPRD(2025)·24 citations
29. 29*

    Phase diagram of bosonic matter with additional derivative interaction

    Leonid M. Satarov🇩🇪 · Igor N. Mishustin🇩🇪 · Horst Stoecker🇩🇪

    Equation of state of uncharged bosonic matter is studied within a field-theoretical approach in the mean-field approximation. Interaction of bosons is described by a scalar field $\sigma$ with a Skyrme-like potential which contains both attractive and repulsive terms. Additionally we introduce the derivative interaction by including factor $(1+\lambda \sigma {)}^{-1}$ in the kinetic part of Lagrangian where $\lambda >0$ is the model parameter. Numerical calculations are made for strongly interacting matter composed of $\alpha$ particles. It is shown that ground-state binding energy and equilibrium density of such matter drop with increasing $\lambda$. The liquid-gas phase transition and the Bose-Einstein condensation are studied by using different thermodynamic variables. We calculate also spinodal lines which give boundaries of metastable states. It is demonstrated that critical temperature decreases with $\lambda$. Both LGPT and bound condensate states disappear above certain maximum value of $\lambda$.

    hep-ph0 citations
30. 30*

    Searches for Power-Law Warped Extra Dimensions

    Sang Hui Im🇰🇷 · Krzysztof Jodłowski🇰🇷

    Extra dimensions with a bulk dilaton field can be power-law warped, unlike the exponential warping in the Randall-Sundrum (RS) model. We show that this mildly warped extra dimension can address the hierarchy problem with a novel Kaluza-Klein (KK) spectrum characterized by lighter feebly coupled KK modes compared to the KK modes in the RS model. We investigate the prospects of searching for signatures of such KK modes at current and future colliders, such as the LHC, CLIC, and FCC-ee using visible decays of KK gravitons. We also update the current bounds and projected limits for the RS model and the linear dilaton (LD) model. Furthermore, we explore the long-lived regime of KK gravitons at beam dump experiments, e.g., FASER2, MATHUSLA, and SHiP, as well as constraints from astrophysical and cosmological observations. We find that combining both kinds of searches will enable comprehensive coverage of the model parameter space relevant to the electroweak hierarchy problem.

    hep-phastro-ph.COhep-thJHEP(2026)·4 citations
31. 31*

    Top-quark Yukawa coupling with a dimension-6 operator

    Ya-Juan Zheng🇯🇵

    We extend the standard top-quark Yukawa coupling with a dimension-6 operator in order to accommodate a CP violating complex phase with manifest gauge invariance. This leads to a new $ttHH$ contact interaction, along with many Goldstone boson couplings. We investigate the impact of the new interactions on a muon collider process ${\mu }^{-}{\mu }^{+}\to {\nu }_{\mu }{\bar{\nu }}_{\mu }t\bar{t}H$ compared with the standard dimension-4 top-Yukawa coupling. The unitarity bounds on the coefficient of the new physics operator is obtained from $W_L^{-}{W}_L^{+}$ and $HH$ initiated processes.

    hep-phEPJ Web Conf.(2024)·0 citations
32. 32*

    Weak nuclear decays deep-underground as a probe of axion dark matter

    Jorge Alda🇮🇹 · Carlo Broggini🇮🇹 · Giuseppe Di Carlo🇮🇹 · Luca Di Luzio🇮🇹 · Denise Piatti🇮🇹 · Stefano Rigolin🇮🇹 · Claudio Toni🇫🇷

    We investigate the time modulation of weak nuclear decays as a method to probe axion dark matter. To this end, we develop a theoretical framework to compute the $\theta$-dependence of weak nuclear decays, including electron capture and $\beta$ decay, which enables us to predict the time variation of weak radioactivity in response to an oscillating axion dark matter background. As an application, we recast old data sets, from the weak nuclear decays of ${}^{40}\text{K}$ and ${}^{137}\text{Cs}$ taken at the underground Gran Sasso Laboratory, in order to set constraints on the axion decay constant, specifically in the axion mass range from few $10^{-23}$eV up to $10^{-19}$eV. We finally propose a new measurement at the Gran Sasso Laboratory, based on the weak nuclear decay of ${}^{40}\text{K}$ via electron capture, in order to explore even shorter timescales, thus reaching sensitivities to axion masses up to $10^{-9}$eV.

    hep-phhep-exnucl-exnucl-thPRD(2025)·17 citations
33. 33*

    Formal Theory at ICHEP 2024

    Sakura Schafer-Nameki🇬🇧

    These proceedings discuss some of the highlights of recent research in Formal Theory. The topics covered range from recent progress in scattering amplitudes, quantum gravity constraints on effective field theories, AdS/CFT, flat space holography, to generalized symmetries.

    hep-phhep-thPoS(2025)·0 citations
34. 34*

    NNLOCAL: completely local subtractions for color-singlet production in hadron collisions

    V. Del Duca🇮🇹 · C. Duhr🇩🇪 · L. Fekésházy🇩🇪 · F. Guadagni🇨🇭 · P. Mukherjee🇩🇪 · G. Somogyi🇭🇺 · F. Tramontano🇮🇹 · S. Van Thurenhout🇭🇺

    We present NNLOCAL, a proof-of-concept parton-level Monte Carlo program implementing the extension of the completely local subtraction scheme CoLoRFulNNLO to the case of color-singlet production in hadron collisions. We have built general local subtraction terms that regularize all single and double unresolved infrared singularities in real radiation phase space. The subtractions are then integrated fully analytically to the required order in the parameter of dimensional regularization. Combining the integrated counterterms with the virtual contributions we demonstrate the cancellation of all infrared poles explicitly. We validate our procedure by computing the fully differential cross section for the production of a Higgs boson at the LHC in an effective field theory with gluons only. Our code provides the first public implementation of a completely local analytic subtraction scheme at next-to-next-to-leading order accuracy.

    hep-phhep-thJHEP(2025)·18 citations
35. 35*

    Cosmological Signatures of Neutrino Seesaw Mechanism

    Chengcheng Han🇨🇳 · Hong-Jian He🇨🇳 · Linghao Song🇨🇳 · Jingtao You🇨🇳

    The tiny neutrino masses are most naturally explained by seesaw mechanism through singlet right-handed neutrinos, which can further explain the matter-antimatter asymmetry in the Universe. In this Letter, we propose a new approach to study cosmological signatures of neutrino seesaw through the interaction between inflaton and right-handed neutrinos that respects the shift symmetry. In our framework, after inflation the inflaton predominantly decays into right-handed neutrinos and its decay rate is modulated by the fluctuations of Higgs field that act as the source of curvature perturbations. This gives a new realization of Higgs modulated reheating, and it produces primordial non-Gaussian signatures that can be measured by the forthcoming large-scale structure surveys. We find that these surveys have the potential to probe a large portion of the neutrino seesaw parameter space, opening up a new window for testing the high scale seesaw mechanism.

    hep-phastro-ph.COgr-qchep-thPRD(2025)·9 citations
36. 36*

    Tame multi-leg Feynman integrals beyond one loop

    Li-Hong Huang🇨🇳 · Rui-Jun Huang🇨🇳 · Yan-Qing Ma🇨🇳

    We introduce a novel structure for Feynman integrals, reformulating them as integrals over a small set of parameters with a fully controllable integrand. The integrand closely resembles one-loop Feynman integrals, and they are very easy to handle. Remarkably, the number of remaining integration parameters is independent of the number of external legs and small -- at most 2 for two-loop integrals and 5 for three-loop integrals -- facilitating the application of a wide range of established methods, both specific to Feynman integrals and more general techniques. This approach is expected to mitigate the computational challenges of multi-loop, multi-leg Feynman integrals. As a proof of concept, we successfully computed two-loop non-planar Feynman integrals with six external legs, demonstrating high efficiency.

    hep-ph8 citations
37. 37*

    Efficient Computation of One-Loop Feynman Integrals and Fixed-Branch Integrals to High Orders in $ϵ$

    Rui-Jun Huang🇨🇳 · Dong-Shan Jian🇨🇳 · Yan-Qing Ma🇨🇳 · Dao-Ming Mu🇨🇳 · Wen-Hao Wu🇨🇳

    We propose a novel method, called the dimension-changing transformation (DCT), to compute one-loop Feynman integrals and recently introduced fixed-branch integrals to arbitrary orders in $ϵ$. The DCT relates one-loop Feynman integrals or fixed-branch integrals in one spacetime dimension to their corresponding quantities with auxiliary mass in any other dimension, making the expansion to high orders in $ϵ$ highly efficient. We applied this method to several examples to demonstrate its validity and efficiency. The approach introduced in this work has been implemented in an open-source C++ package, available at \href{https://gitlab.com/multiloop-pku/dct}{https://gitlab.com/multiloop-pku/dct}.

    hep-phPRD(2025)·8 citations
38. 38*

    Soft-gluon coupling and the TMD parton branching Sudakov form factor

    A. Bermudez Martinez🇩🇪 · F. Hautmann🇧🇪 · L. Keersmaekers🇧🇪 · A. Lelek🇧🇪 · M. Mendizabal Morentin🇩🇪 · S. Taheri Monfared🇩🇪 · A.M. van Kampen🇧🇪

    The evolution of transverse momentum dependent (TMD) distributions in Quantum Chromodynamics (QCD) can be formulated in a parton branching (PB) framework. We show that next-to-next-to-leading-logarithm (NNLL) accuracy can be achieved in this framework by using the concept of soft-gluon physical coupling. We present results for the TMD distributions and for the Collins-Soper kernel controlling rapidity evolution. The results pave the way for PB predictions at NNLL level for physical observables at the Large Hadron Collider (LHC) and future colliders.

    hep-phPLB(2025)·14 citations
39. 39*

    Probing Gravitational Dark Matter with Ultra-high Frequency Gravitational Waves

    Yong Xu🇩🇪

    The evidence for the existence of dark matter (DM) is compelling, yet its nature remains elusive. A minimal scenario involves DM interacting solely through gravity. However, the detection would be extremely challenging. In the early Universe, such DM can be unavoidably generated via annihilation of particles in the standard model (SM) thermal plasma. It is known that the SM thermal plasma also produces gravitational waves (GWs). In this study, we establish a simple connection between the amplitude of thermal GWs and the properties of pure gravitational DM. Notably, future GW experiments in the ultra-high frequency regime have the potential to shed light on the mass and spin of pure gravitational DM.

    hep-phastro-ph.COPLB(2025)·5 citations
40. 40*

    Strange-antistrange and charm-anticharm asymmetries of pion in 't Hooft model

    Mingliang Zhu🇨🇳 · Siwei Hu🇨🇳 · Yu Jia🇨🇳 · Zhewen Mo🇨🇳 · Xiaonu Xiong🇨🇳

    As a sequel of our preceding work [S. Hu et al., Phys. Rev. D 108 (2023) 9, 094040], we investigate the strange-antistrange and charm-anticharm asymmetries in the parton distribution functions (PDFs) of a light flavored meson, exemplified by the first excited pion in the 't Hooft model, {\it viz.}, QCD in two spacetime dimensions with infinite number of colors. Counted as an $\mathcal{O}(1/N_c)$ effect, the intrinsic strange content necessarily originates from the higher Fock component of the light flavored meson, which entails infinite towers of $K$ and $\overline{K}$ mesons. Numerical studies reveal that, with $m_u/m_d=1/2$, the $s$-$\bar{s}$ and $c$-$\bar{c}$ asymmetries of the first excited ${\pi }^{-}$ can reach per cents level. While the $s$-$\bar{s}$ asymmetry predicted from the meson cloud model (MCM) grossly align with the rigorous approach, there exists severe discrepancy between two approaches on the $c$-$\bar{c}$ asymmetry.

    hep-ph0 citations
41. 41*

    Accidental Peccei-Quinn Symmetry From Gauged U(1) and a High Quality Axion

    K.S. Babu🇺🇸 · Bhaskar Dutta🇺🇸 · Rabindra N. Mohapatra🇺🇸

    We construct explicit models that solve the axion quality problem originating from quantum gravitational effects. The general strategy we employ is to supplement the Standard Model and its grand unified extensions by an anomaly-free axial $U(1{)}_a$ symmetry that is gauged. We show that for several choices of the gauge quantum numbers of the fermions, this setup leads to an accidental $U(1)$ symmetry with a QCD anomaly which can be identified as the Peccei-Quinn (PQ) symmetry that solves the strong CP problem. The $U(1{)}_a$ gauge symmetry controls the amount of explicit PQ symmetry violation induced by quantum gravity, resulting in a high quality axion. We present two classes of models employing this strategy. In the first class (models I and II), the axial $U(1{)}_a$ gauge symmetry acts on vector-like quarks leading to an accidental KSVZ-type axion. The second class (model III) is based on $SO(10)$ grand unified theory extended by a gauged $U(1{)}_a$ symmetry that leads to a hybrid KSVZ--DFSZ type axion. The couplings of the axion to the electron and the nucleon are found to be distinct in this class of hybrid models from those in the KSVZ and DFSZ models, when the axion is identified as the dark matter of the universe, which can be used to test these models. Interestingly, all models presented here have domain wall number of one, which is free of cosmological problems that typically arise in axion models.

    hep-phJHEP(2026)·11 citations
42. 42*

    Measuring Quantum Discord at the LHC

    Tao Han🇺🇸 · Matthew Low🇺🇸 · Navin McGinnis🇺🇸 · Shufang Su🇺🇸

    There has been an increasing interest in exploring quantities associated with quantum information at colliders. We perform a detailed analysis describing how to measure the quantum discord in the top anti-top quantum state at the Large Hadron Collider (LHC). While for pure states, quantum discord, entanglement, and Bell nonlocality all probe the same correlations, for mixed states they probe different aspects of quantum correlations. The quantum discord, in particular, is interesting because it aims to encapsulate all correlations between systems that cannot have a classical origin. We employ two complementary approaches for the study of the top anti-top system, namely the decay method and the kinematic method. We highlight subtleties associated with measuring discord for reconstructed quantum states at colliders. Usually quantum discord is difficult to compute due to an extremization that must be performed. We show, however, that for the $t\bar{t}$ system this extremization can be performed analytically and we provide closed-form formulas for the quantum discord. We demonstrate that at the high luminosity LHC, discord is projected to be measurable with a precision of approximately 5% using the decay method and sub-percent levels using the kinematic method. Even with current LHC datasets, discord can be measured with 1-2% precision with the kinematic method. By systematically investigating quantum discord for the first time through a detailed collider analysis, this work expands the toolkit for quantum information studies in particle physics and lays the groundwork for deeper insights into the quantum properties in high-energy collisions.

    hep-phhep-exquant-phJHEP(2025)·65 citations
43. 43*

    Probing Heavy Axion-like Particles from Massive Stars with X-rays and Gamma Rays

    James H. Buckley🇺🇸 · P. S. Bhupal Dev🇺🇸 · Francesc Ferrer🇺🇸 · Takuya Okawa🇺🇸

    The hot interiors of massive stars in the later stages of their evolution provide an ideal place for the production of heavy axion-like particles (ALPs) with mass up to O(100 keV) range. We show that a fraction of these ALPs could stream out of the stellar photosphere and subsequently decay into two photons that can be potentially detected on or near the Earth. In particular, we estimate the photon flux originating from the spontaneous decay of heavy ALPs produced inside Horizontal Branch and Wolf-Rayet stars, and assess its detectability by current and future $X$-ray and gamma-ray telescopes. Our results indicate that current and future telescopes can probe axion-photon couplings down to $g_{a\gamma }\sim 4\times 10^{-11}$ GeV${}^{-1}$ for $m_a\sim 10-100$ keV, which covers new ground in the ALP parameter space.

    hep-phastro-ph.COastro-ph.HEastro-ph.SR6 citations
44. 44*

    Precise Determination of the Strong Coupling Constant from Dijet Cross Sections up to the Multi-TeV Range

    Fazila Ahmadova🇩🇪 · Daniel Britzger🇩🇪 · Xuan Chen🇨🇳 · Johannes Gäßler🇩🇪 · Aude Gehrmann-De Ridder🇨🇭 · Thomas Gehrmann🇨🇭 · Nigel Glover🇬🇧 · Claire Gwenlan🇬🇧 · Gudrun Heinrich🇩🇪 · Alexander Huss🇨🇭 · Lucas Kunz🇩🇪 · João Pires🇵🇹 · Klaus Rabbertz🇩🇪 · Mark Sutton🇬🇧

    We determine the value of the strong coupling ${\alpha }_{\text{s}}$ and study its running over a wide range of scales as probed by the dijet production process at hadron colliders, based on an NNLO QCD analysis of LHC dijet data. From a large subset of these data a value of ${\alpha }_{\text{s}}(m_{\text{Z}})=0.1178\pm 0.0022$ is obtained for the strong coupling at the scale of the Z-boson mass $m_{\text{Z}}$, using the invariant mass of the dijet system to select the scale where ${\alpha }_{\text{s}}$ is probed. The combination of different data sets enhances the reach and precision of the analysis in the mutli-TeV range and allows for the first determination of ${\alpha }_{\text{s}}$ up to scales of 7 TeV. Complementing the LHC data with dijet cross sections measured at the HERA electron-proton collider, the kinematic range is extended to test the running of the strong coupling towards smaller scales. Our results exhibit excellent agreement with predictions based on the renormalization group equation of QCD, and represent a comprehensive test of the asymptotic behavior of QCD, spanning more than three orders of magnitude in energy scale.

    hep-phhep-exPRL(2025)·10 citations
45. 45*

    Quantum algorithms for the simulation of QCD processes in the perturbative regime

    Herschel A. Chawdhry🇺🇸 · Mathieu Pellen🇩🇪

    Theoretical predictions for high-energy collision processes at particle colliders, such as the Large Hadron Collider (LHC), rely on calculations in perturbative Quantum Chromodynamics (QCD), which are often computationally challenging. In these conference proceedings, we explore the possibility of using quantum computers to simulate QCD processes in the perturbative QCD regime. In particular, as a first step towards that goal, we present quantum circuits to simulate the colour part of perturbative QCD. The circuits are validated by implementing them on a simulated quantum computer and verifying the colour factors for several example Feynman diagrams.

    hep-phhep-thquant-ph1 citation
46. 46*

    Vector-like quark doublets, weak-basis invariants and CP violation

    F. Albergaria🇵🇹 · J. F. Bastos🇵🇹 · B. Belfatto🇩🇪 · G. C. Branco🇵🇹 · J. T. Penedo🇮🇹 · A. Rodríguez-Sánchez🇪🇸 · J. I. Silva-Marcos🇵🇹

    We study Standard Model extensions with isodoublet vector-like quarks with standard charges. Their presence induces right-handed charged and neutral currents. We identify minimal sets of independent parameters characterizing these extensions, describe useful weak bases, and provide parameterizations for all quark mixing. We analyze the intricacies of CP violation in such scenarios, finding a complete set of CP-odd invariants for the single doublet case. Crucially, we uncover a connection between weak-basis invariants and effective rephasing invariants involving only standard quarks. These results allow us to explore the phenomenology of doublet vector-like quarks through a rephasing-invariant analysis, with an emphasis on CP violation, including the potential role of these fields in explaining the Cabibbo angle anomalies.

    hep-phJHEP(2025)·8 citations
47. 47*

    Two-component Dark Matter and low scale Thermal Leptogenesis

    Subhaditya Bhattacharya🇮🇳 · Devabrat Mahanta🇮🇳 · Niloy Mondal🇮🇳 · Dipankar Pradhan🇮🇳

    The observable cosmos exhibits sizable baryon asymmetry, small active neutrino masses, and the presence of dark matter (DM). To address these phenomena together, we propose a two component DM scenario in an extension of Scotogenic model, imposing ${\mathbb{Z}}_2\otimes {\mathbb{Z}}_2^{\prime }$ symmetry. The electroweak sphaleron process converts the ${\mathrm{Y}}_{\mathrm{B}-\mathrm{L}}^{}$ yield, generated through the Leptogenesis mechanism, into the baryon asymmetry (${\mathrm{Y}}_{\mathrm{\Delta B}}^{}$) at ${\mathrm{T}}_{\mathrm{sph}}\sim 130$ GeV, the sphalerons decoupling temperature. In this framework, the CP asymmetry as well as the radiative neutrino mass generation explicitly involve the two DM particles, thus establishing a correlation between the baryon asymmetry, DM and observed active neutrino masses. We study in details the allowed parameter space available after considering all the constraints from the three phenomena as well as from the collider search limits, and outline the region which could potentially be tested in future DM detection experiments through direct or indirect detection searches, lepton flavor-violating decays, etc.

    hep-phJCAP(2025)·7 citations
48. 48*

    Deep learning optimal molecular scintillators for dark matter direct detection

    Cameron Cook🇬🇧 · Carlos Blanco🇺🇸 · Juri Smirnov🇬🇧

    Direct searches for sub-GeV dark matter are limited by the intrinsic quantum properties of the target material. In this proof-of-concept study, we argue that this problem is particularly well suited for machine learning. We demonstrate that a simple neural architecture consisting of a variational autoencoder and a multi-layer perceptron can efficiently generate unique molecules with desired properties. In specific, the energy threshold and signal (quantum) efficiency determine the minimum mass and cross section to which a detector can be sensitive. Organic molecules present a particularly interesting class of materials with intrinsically anisotropic electronic responses and $\mathcal{O}$(few) eV excitation energies. However, the space of possible organic compounds is intractably large, which makes traditional database screening challenging. We adopt excitation energies and proxy transition matrix elements as target properties learned by our network. Our model is able to generate molecules that are not in even the most expansive quantum chemistry databases and predict their relevant properties for high-throughput and efficient screening. Following a massive generation of novel molecules, we use clustering analysis to identify some of the most promising molecular structures that optimise the desired molecular properties for dark matter detection.

    hep-phcond-mat.mtrl-scihep-exhep-th+1PRD(2025)·8 citations
49. 49*

    Classification of the Discrete Symmetries for the Four-Higgs-Doublet Model

    Jiazhen Shao🇨🇳

    The multi-Higgs model (NHDM) is a class of new physics models that go beyond the Standard Model with fewer assumptions, namely by postulating the existence of multiple Higgs doublets, while yielding a rich phenomenology. Among them, the Four-Higgs-Doublet model (4HDM) has attracted increasing attention in recent years, with nearly a hundred papers dedicated to its study. Scientists have attempted to use it to explain many phenomena that the Standard Model cannot account for, such as dark matter, fermion mass hierarchies, neutrino masses, cosmological phase transitions, and cosmic strings, among others. In these efforts, imposing finite symmetries on the 4HDM is a standard procedure, because finite symmetries are central to explaining many physical phenomena, such as dark matter, and can also constrain excessively large parameter spaces technically. Therefore, given the recent attention to 4HDM and the importance of finite symmetries in model building, it is crucial from a mathematical perspective to classify all possible finite symmetries, as the classification results can guide model construction and phenomenological studies. So far, two scenarios of discrete symmetries of 4HDM have been classified, but there are still cases that haven't been studied. During our study, we found out situations that have never appeared in 2HDM or 3HDM, and we developed many new techniques to help us handle the difficulties. Therefore, before any further progresses are made towards a full classification, it is timely to revisit the current progress of 4HDM discrete symmetry classification in a beginner-friendly manner, and to provide a look towards future research.

    hep-ph0 citations
50. 50*

    Measurement of the hard exclusive ${\pi }^0$ muoproduction cross section at COMPASS

    G. D. Alexeev · M. G. Alexeev · C. Alice · A. Amoroso · V. Andrieux · V. Anosov · K. Augsten · W. Augustyniak · C. D. R. Azevedo · B. Badelek · J. Barth · R. Beck and 161 other authors

    A new and detailed measurement of the cross section for hard exclusive neutral-pion muoproduction on the proton was performed in a wide kinematic region, with the photon virtuality $Q^2$ ranging from 1 to 8 (GeV/$c$)${}^2$ and the Bjorken variable $x_{\mathrm{Bj}}$ ranging from 0.02 to 0.45. The data were collected at COMPASS at CERN using 160 GeV/$c$ longitudinally polarised ${\mu }^{+}$ and ${\mu }^{-}$ beams scattering off a 2.5 m long liquid hydrogen target. From the average of the measured ${\mu }^{+}$ and ${\mu }^{-}$ cross sections, the virtual-photon--proton cross section is determined as a function of the squared four-momentum transfer between the initial and final state proton in the range 0.08 (GeV/$c$)${}^2$ $<|t|<$ 0.64 (GeV/$c$)${}^2$. From its angular distribution, the combined contribution of transversely and longitudinally polarised photons are determined, as well as transverse--transverse and longitudinal--transverse interference contributions. They are studied as functions of four-momentum transfer $|t|$, photon virtuality $Q^2$ and virtual-photon energy $\nu$. The longitudinal--transverse interference contribution is found to be compatible with zero. The significant transverse--transverse interference contribution reveals the existence of a dominant contribution by transversely polarized photons. This provides clear experimental evidence for the chiral-odd GPD ${\overline{E}}_T$. In addition, the existence of a non-negligible contribution of longitudinally polarized photons is suggested by the $|t|$-dependence of the cross section at $x_{\mathrm{Bj}}<$ 0.1 . Altogether, these results provide valuable input for future modelling of GPDs and thus of cross sections for exclusive pseudo-scalar meson production. Furthermore, they can be expected to facilitate the study of next-to-leading order corrections and higher-twist contributions.

    ↳ hep-exhep-phPLB(2025)·5 citations
51. 51*

    Search for Solar Boosted Dark Matter Particles at the PandaX-4T Experiment

    Guofang Shen🇨🇳 · Zihao Bo🇨🇳 · Wei Chen🇨🇳 · Xun Chen🇨🇳 · Yunhua Chen🇨🇳 · Zhaokan Cheng🇨🇳 · Xiangyi Cui🇨🇳 · Yingjie Fan🇨🇳 · Deqing Fang🇨🇳 · Zhixing Gao🇨🇳 · Lisheng Geng🇨🇳 · Karl Giboni🇨🇳 and 91 other authors

    We present a novel constraint on light dark matter utilizing $1.54$ tonne$\cdot$year of data acquired from the PandaX-4T dual-phase xenon time projection chamber. This constraint is derived through detecting electronic recoil signals resulting from the interaction with solar-enhanced dark matter flux. Low-mass dark matter particles, lighter than a few MeV/$c^2$, can scatter with the thermal electrons in the Sun. Consequently, with higher kinetic energy, the boosted dark matter component becomes detectable via contact scattering with xenon electrons, resulting in a few keV energy deposition that exceeds the threshold of PandaX-4T. We calculate the expected recoil energy in PandaX-4T considering the Sun's acceleration and the detection capabilities of the xenon detector. The first experimental search results using the xenon detector yield the most stringent cross-section of $3.51\times 10^{-39}{\mathrm{cm}}^2$ at $0.08\mathrm{MeV}$/$c^2$ for a solar boosted dark matter mass ranging from $0.02$ to $10\mathrm{MeV}$/$c^2$, achieving a 23 fold improvement compared with earlier experimental studies.

    ↳ hep-exhep-phPRL(2025)·9 citations
52. 52*

    The nucleon properties in finite temperature and density with Gaussian fluctuations

    Peixin Weng🇨🇳 · Bingtao Li🇨🇳 · Yiming Lyu🇨🇳 · Song Shu🇨🇳 · Hui Zhang🇨🇳

    We investigate the properties of nucleons at finite temperature and density using a two-flavor quark meson model with Gaussian fluctuations that extend beyond the mean-field approximation. Our findings suggest that Gaussian fluctuations lead to a non-monotonic behavior of the nucleon mass as a function of temperature and density, which may play an important role in the study of the hadronization process of relativistic heavy-ion collisions. Moreover, we observe an increase in the nucleon radius due to Gaussian fluctuations, suggesting an effective repulsive force akin to the Casimir effect, as observed in the gold-bromobenzene-silica system. This study offers new insights into how temperature, density, and quantum fluctuations affect the structure and properties of nucleons under extreme conditions.

    ↳ hep-thhep-phnucl-thPLB(2025)·1 citation
53. 53*

    Spectral sum rules and phase transition in strongly coupled QCD

    Yi-Lun Du🇨🇳 · Nan Su · Konrad Tywoniuk🇳🇴

    By incorporating contributions from both the (chromo)electric scale $gT$ and (chromo)magnetic scale $g^{2}T$, we establish spectral sum rules of quarks for strongly coupled QCD that respect Fermi-Dirac statistics as required by quantum mechanics. In sharp contrast to QED and weakly coupled QCD whose spectral functions consist of discontinuous zero-dimensional (poles) and one-dimensional (branch cuts) non-analytic contributions from real energy $p_0\in \mathbb{R}$, the derived spectral function for strongly coupled quarks features continuous but non-analytic contributions from complex energy $p_0\in \mathbb{C}$ that are two-dimensional in nature. In light of the novel sum rules, we uncover an intrinsic QCD transition between a three-mode phase at small coupling and a one-mode phase at large coupling. The transition is induced by the magnetic scale that generates a massless hydro-like mode with the genuine non-Abelian feature of positivity violation and serving as the Goldstone mode of the Lorentz symmetry breaking. The thermal mass serves as an order parameter of the transition and vanishes at large coupling in line with phenomenological predictions from Dyson-Schwinger equations and gauge/gravity duality. This result provides novel insights into the mechanism of the QCD deconfinement transition.

    ↳ hep-thhep-lathep-phnucl-th2 citations
54. 54*

    Physics consistent machine learning framework for inverse modeling with applications to ICF capsule implosions

    Daniel A. Serino · Evan Bell · Marc Klasky · Ben S. Southworth🇺🇸 · Balasubramanya Nadiga · Trevor Wilcox · Oleg Korobkin🇺🇸

    In high energy density physics (HEDP) and inertial confinement fusion (ICF), predictive modeling is complicated by uncertainty in parameters that characterize various aspects of the modeled system, such as those characterizing material properties, equation of state (EOS), opacities, and initial conditions. Typically, however, these parameters are not directly observable. What is observed instead is a time sequence of radiographic projections using X-rays. In this work, we define a set of sparse hydrodynamic features derived from the outgoing shock profile and outer material edge, which can be obtained from radiographic measurements, to directly infer such parameters. Our machine learning (ML)-based methodology involves a pipeline of two architectures, a radiograph-to-features network (R2FNet) and a features-to-parameters network (F2PNet), that are trained independently and later combined to approximate a posterior distribution for the parameters from radiographs. We show that the estimated parameters can be used in a hydrodynamics code to obtain density fields and hydrodynamic shock and outer edge features that are consistent with the data. Finally, we demonstrate that features resulting from an unknown EOS model can be successfully mapped onto parameters of a chosen analytical EOS model, implying that network predictions are learning physics, with a degree of invariance to the underlying choice of EOS model.

    ↳ physics.comp-phcs.LGhep-ph0 citations
55. 55*

    Stiffening of matter in quark-hadron continuity: a mini-review

    Toru Kojo🇯🇵

    Recent observations of neutron stars, combined with causality, thermodynamic stability, and nuclear constraints, indicate a rapid stiffening of QCD matter at densities slightly above nuclear saturation density ($n_0\simeq 0.16{\mathrm{fm}}^{-3}$). The evolution of the stiffening is faster than expected from purely nucleonic models with many-body repulsion. Taking into account the quark substructure of baryons, we argue that the saturation of quark states occurs at $\sim$ 2-3$n_0$, driving quark matter formation even before baryonic cores of radius $\sim$0.5 fm spatially overlap. We describe the continuous transitions from hadronic to quark matter within a quarkyonic matter model in which gluons are assumed to remain confining at densities of interest. To obtain analytic insight into the transient regime, we construct an ideal model of quarkyonic matter, the {\it IdylliQ} model, in which one can freely switch from baryonic to quark descriptions and vice versa.

    ↳ nucl-thastro-ph.HEhep-phJ.Subatomic Part.Cosmol.(2025)·12 citations
56. 56*

    Transport coefficients of dense nucleon matter at low temperature

    Jianing Li🇨🇳 · Weiyao Ke🇨🇳

    The transport property of cold and dense nucleon matter is important for nuclear physics but is relatively less studied than that at finite temperatures. In this paper, we present a primary study of bulk and shear viscosities in the limit $T/{\mu }_B\ll 1$, where $T$ and ${\mu }_B$ are the temperature and the baryon chemical potential. The analysis is performed for a generic system where nucleons are dressed by the condensation of both scalar and vector interactions. Under the relaxation time approximation of the Boltzmann equation, we compute the viscosities of the system to leading power in $T/{\mu }_B$ expansion and establish a relation between the thermodynamic potential and transport coefficients, including bulk viscosity ($\zeta$) and shear viscosity ($\eta$). It is found that hydrodynamic stability ($\zeta >0$) imposes additional constraints on the thermodynamic potential. As an example, these relations are applied to the Walecka model. The fluid properties of the cold and dense nucleon matter are characterized by the dimensionless combination of viscosities times the quasi-Fermi momentum over the enthalpy. Furthermore, we discuss the implication of the stability condition on the range of applicability of the model.

    ↳ nucl-thcond-mat.str-elhep-phhep-thPRC(2025)·1 citation
57. 57*

    One-loop Matching Factors for Singlet Quasi-Parton Distribution Functions in the Hybrid-Ratio Scheme

    Yi-Xian Chen🇹🇼 · Jiunn-Wei Chen🇹🇼

    The one loop matching kernels between parton distribution functions (PDFs) for parton $i=u,d,s,g$ and their corresponding quasi-PDFs are computed at one loop in the hybrid-ratio scheme. We found that, in addition to the conservation of the quasi-quark number for each flavor, the second moment $⟨x{⟩}_{\tilde{i}}=⟨x{⟩}_i$ of quasi-PDF of parton $i$ (denoted as $\tilde{i}$) and PDF of parton $i$ is the same in our approach. This is demonstrated numerically using the CTEQ14 global analysis as input.

    ↳ hep-lathep-phPRD(2025)·3 citations
58. 58*

    Cosmological stimulated emission

    Atsuhisa Ota🇨🇳

    We study stimulated emission and absorption of gravitons in a squeezed vacuum state immersed in a thermal radiation bath. Employing one-loop interaction-picture perturbation theory, we track the time evolution of the graviton number operator and its expectation value in the squeezed vacuum, which characterizes the inflationary graviton state. In a Minkowski background with a thermal bath as a toy example, we demonstrate that the net graviton emission or absorption rate depends sensitively on the initial squeezing parameters. As a thought experiment, we consider LIGO/Virgo-like detectors operating in radiation at temperatures of order 0.1 GeV and find that graviton occupation numbers at frequencies of order 100 Hz can be significantly enhanced, suggesting a novel mechanism for amplifying gravitational-wave signals. Although these conditions exceed current experimental capabilities, they point toward potential future advances in detection. Extending our analysis to an expanding, radiation-dominated universe, we show that subhorizon gravitons undergo stimulated absorption, while superhorizon modes exhibit secular logarithmic growth, indicating the breakdown of perturbative methods and motivating further investigation. These findings open a new direction for exploring graviton coherence effects in realistic cosmological and laboratory settings.

    ↳ astro-ph.COgr-qchep-phhep-thEPJC(2025)·7 citations
59. 59*

    Cascading from $\mathcal{N}=2$ Supersymmetric Yang-Mills Theory to Confinement and Chiral Symmetry Breaking in Adjoint QCD

    Eric D'Hoker🇺🇸 · Thomas T. Dumitrescu🇺🇸 · Efrat Gerchkovitz🇮🇱 · Emily Nardoni🇺🇸

    We argue that adjoint QCD in 3+1 dimensions, with any $SU(N)$ gauge group and two Weyl fermion flavors (i.e. one adjoint Dirac fermion), confines and spontaneously breaks its chiral symmetries via the condensation of a fermion bilinear. We flow to this theory from pure $\mathcal{N}=2$ SUSY Yang-Mills theory with the same gauge group, by giving a SUSY-breaking mass $M$ to the scalars in the $\mathcal{N}=2$ vector multiplet. This flow can be analyzed rigorously at small $M$, where it leads to a deconfined vacuum at the origin of the $\mathcal{N}=2$ Coulomb branch. The analysis can be extended to all $M$ using an Abelian dual description that arises from the $N$ multi-monopole points of the $\mathcal{N}=2$ theory. At each such point, there are $N-1$ hypermultiplet Higgs fields $h_m^{i=1,2}$, which are $SU(2{)}_R$ doublets. We provide a detailed study of the phase diagram as a function of $M$, by analyzing the semi-classical phases of the dual using a combination of analytic and numerical techniques. The result is a cascade of first-order phase transitions, along which the Higgs fields $h_m^i$ successively turn on, and which interpolates between the Coulomb branch at small $M$, where all $h_m^i=0$, and a maximal Higgs branch, where all $h_m^i\ne 0$, at sufficiently large $M$. We show that this maximal Higgs branch precisely matches the confining and chiral symmetry breaking phase of two-flavor adjoint QCD, including its broken and unbroken symmetries, its massless spectrum, and the expected large-$N$ scaling of various observables. The spontaneous breaking pattern $SU(2{)}_R\to U(1{)}_R$, consistent with the Vafa-Witten theorem, is ensured by an intricate alignment mechanism for the $h_m^i$ in the dual, and leads to a $\mathbb{C}{\mathbb{P}}^1$ sigma model of increasing radius along the cascade.

    ↳ hep-thcond-mat.str-elhep-lathep-phPhys.Rept.(2026)·6 citations
60. 60*

    Open String Amplitudes: Singularities, Asymptotics, and New Representations

    Nima Arkani-Hamed🇺🇸 · Carolina Figueiredo🇺🇸 · Grant N. Remmen🇺🇸

    Open string amplitudes at tree level have been studied for over fifty years, but there is no known analytic form for general $n$-point amplitudes, and their conventional representation in terms of worldsheet integrals does not make many of their most basic physical properties manifest. Recently, a formulation of these amplitudes exposing the underlying "binary geometry" via the use of "$u$" variables has given us many insights into their basic features. In this paper, we initiate a systematic exploration of fundamental aspects of open string amplitudes from this new point of view. We begin by giving explicit expressions for the factorization of amplitudes at general massive levels. We then study the asymptotic behavior when subsets of kinematic variables become large, delineating regimes with exponential (generalized hard scattering) and power-law (generalized Regge) behavior. We also give precise expressions for the asymptotics, which reveal another example of the recently observed property of factorization away from poles. We finally derive new recursion relations and infinite series representations for the amplitude, and for five points, we present a new closed-form expression for the amplitude that for the first time gives its analytic continuation to all of kinematic space.

    ↳ hep-thhep-phJHEP(2025)·29 citations
61. 61*

    The Casimir Effect in (3+1)-dimensional lattice Yang-Mills theory at finite temperature: the unexpected universality of quarkiton and glueton boundary states

    Maxim N. Chernodub🇫🇷 · Vladimir A. Goy🇷🇺 · Alexander V. Molochkov🇷🇺 · Konstantin R. Pak🇷🇺 · Alexey S. Tanashkin🇷🇺

    In our earlier work on the Casimir effect in (3+1)-dimensional Yang-Mills theory, we identified two novel nonperturbative states arising in QCD with boundaries: the glueton and the quarkiton. The glueton, or "gluon exciton", is a colorless bound state formed by gluons interacting with their negatively colored images in a chromometallic mirror. The quarkiton, or "quark exciton", is a meson-like state comprising a heavy quark attracted to its image through the mirror. In this study, we extend our analysis to finite temperatures near the deconfinement phase transition $(T\approx 0.78T_c)$, where we observe a linear potential between a color-neutral chromometallic mirror and a heavy test quark. Our result suggests that the quarkiton state can have a physical relevance since mirrors for photons and, presumably, gluons can be realized in field theories as domain-wall solutions. Furthermore, we find a striking universality: the ratio of the glueton mass to the bulk $0^{++}$ glueball mass - defining the bulk mass gap - matches the ratio of the quarkiton string tension to the string tension between quark and anti-quark in the absence of the mirror, with a value $\mathcal{R}=0.294(11)$.

    ↳ hep-latcond-mat.otherhep-phhep-thPoS(2025)·0 citations
62. 62*

    Gravitational waves from cosmic strings for pedestrians

    Kai Schmitz🇩🇪 · Tobias Schroeder🇩🇪

    Cosmic strings represent an attractive source of gravitational waves (GWs) from the early Universe. However, numerical computation of the GW signal from cosmic strings requires the evaluation of complicated integral and sum expressions, which can become computationally costly in large parameter scans. This motivates us to rederive the GW signal from a network of local stable cosmic strings in the Nambu-Goto approximation and based on the velocity-dependent one-scale model from a ``pedestrian'' perspective. That is, we derive purely analytical expressions for the total GW spectrum, which remain exact wherever possible and whose error can be tracked and reduced in a controlled way in crucial situations in which we are forced to introduce approximations. In this way, we obtain powerful formulas that, unlike existing results in the literature, are valid across the entire frequency spectrum and across the entire conceivable range of cosmic-string tensions. We provide an in-depth discussion of the GW spectra thus obtained, including their characteristic break frequencies and approximate power-law behaviors, comment on the effect of changes in the effective number of degrees of freedom during radiation domination, and conclude with a concise summary of our main formulas that can readily be used in future studies.

    ↳ astro-ph.COgr-qchep-phJCAP(2026)·14 citations
63. 63*

    Quantum Diffusion Model for Quark and Gluon Jet Generation

    Mariia Baidachna · Rey Guadarrama · Gopal Ramesh Dahale🇮🇳 · Tom Magorsch🇩🇪 · Isabel Pedraza · Konstantin T. Matchev🇺🇸 · Katia Matcheva🇺🇸 · Kyoungchul Kong🇺🇸 · Sergei Gleyzer🇺🇸

    Diffusion models have demonstrated remarkable success in image generation, but they are computationally intensive and time-consuming to train. In this paper, we introduce a novel diffusion model that benefits from quantum computing techniques in order to mitigate computational challenges and enhance generative performance within high energy physics data. The fully quantum diffusion model replaces Gaussian noise with random unitary matrices in the forward process and incorporates a variational quantum circuit within the U-Net in the denoising architecture. We run evaluations on the structurally complex quark and gluon jets dataset from the Large Hadron Collider. The results demonstrate that the fully quantum and hybrid models are competitive with a similar classical model for jet generation, highlighting the potential of using quantum techniques for machine learning problems.

    ↳ quant-phcs.LGhep-ph1 citation
64. 64*

    Effects of asymmetric dark matter on a magnetized neutron star: A two-fluid approach

    Pinku Routaray🇮🇳 · Vishal Parmar🇮🇹 · H. C. Das🇮🇹 · Bharat Kumar🇮🇳 · G. F. Burgio🇮🇹 · H.-J. Schulze🇮🇹

    We study the interaction between dark matter (DM) and highly magnetized neutron stars (NSs), focusing on how DM particle mass, mass fraction, and magnetic field (MF) strength affect NS structure and stability. We consider self-interacting, nonannihilating, asymmetric fermionic DM that couples to NSs only through gravitational interaction. Using the Quantum Monte Carlo Relativistic Mean Field (QMC-RMF4) model with density-dependent magnetic fields, we investigate the magnetized equation of state and examine the accumulation of DM under various conditions. Our results show that as the DM fraction increases, the maximum gravitational mass of the NS decreases, especially for heavier DM particles, while lighter DM particles can induce a transition from a dark core to a halo structure, increasing the maximum mass. Strong MFs soften the equation of state and reduce the dark mass a NS core can retain before transitioning to a halo. By comparing our results with observations from Neutro Star Interior Composition Explorer and GW170817, we identify the possible range of DM parameters for these objects. We find that the magnetic field slightly changes these limits, mainly affecting the maximum NS mass and tidal deformability. These findings provide key insights into how DM and MF jointly shape the mass-radius relation and the stability of DM-admixed magnetized NSs.

    ↳ nucl-thastro-ph.HEgr-qchep-phPRD(2025)·14 citations
65. 65*

    Gravitational EFT for dissipative open systems

    Pak Hang Chris Lau🇨🇳 · Kanji Nishii🇯🇵 · Toshifumi Noumi🇯🇵

    We elaborate on the effective field theory (EFT) construction for dissipative open systems coupled to dynamical gravity, in light of recent developments on the EFT of dissipative hydrodynamics (HydroEFT). Our construction is based on the Schwinger-Keldysh formalism and its symmetries as well as microscopic unitarity. A key aspect of dynamical gravity is that gravity couples to all degrees of freedom universally, hence the EFT has to take into account the energy-momentum tensor of the environment to which the energy escapes from the dissipative system of interest. We incorporate this effect by modeling the environment based on HydroEFT, assuming validity of the derivative expansion of the environment sector. For illustration, we apply our EFT recipe to a dissipative scalar field coupled to dynamical gravity that can be used, e.g., for dissipative inflation. In particular we quantify impacts of fluctuations in the environment sector on the scalar dynamics. We also apply the same framework to dissipative gravity, discussing dissipative gravitational waves and the generalized second law of black hole thermodynamics.

    ↳ hep-thastro-ph.COcond-mat.stat-mechgr-qc+1JHEP(2025)·19 citations
66. 66*

    Hint at an axion-like particle from GRB 221009A

    Giorgio Galanti🇮🇹 · Lara Nava🇮🇹 · Marco Roncadelli🇮🇹 · Fabrizio Tavecchio🇮🇹 · Giacomo Bonnoli🇮🇹

    The detection by the LHAASO Collaboration of the gamma-ray burst GRB 221009A at redshift $z=0.151$ with energies up to $(13-18)\mathrm{TeV}$ challenges conventional physics. Photons emitted with energies above $10\mathrm{TeV}$ at this redshift can hardly be observed on Earth due to their interaction with the extragalactic background light (EBL). We show that indeed the LHAASO Collaboration should not have observed photons with energies above $10\mathrm{TeV}$ if the state-of-the-art EBL model by Saldana-Lopez et al. is taken into account. A problem therefore arises: the Universe should be more transparent than currently believed. We also show that the issue is solved if we introduce the interaction of photons with axion-like particles (ALPs). ALPs are predicted by String Theory, are among the best candidates for dark matter and can produce spectral and polarization effects on astrophysical sources in the presence of external magnetic fields. In particular, for GRB 221009A, photon-ALP oscillations occur within the crossed magnetized media, i.e. the host galaxy, the extragalactic space, the Milky Way, partially reducing the EBL absorption to a level that explains the LHAASO detection of GRB 221009A and its observed spectrum without the need of contrived choices of parameter values, which are instead compulsory within proposed emission models within conventional physics. This fact regarding GRB 221009A represents a strong hint at the ALP existence, which adds to two other indications coming from blazars, a class of active galactic nuclei.

    ↳ astro-ph.HEhep-ph3 citations
67. 67*

    Topological Responses of the Standard Model Gauge Group

    Zheyan Wan🇨🇳 · Juven Wang🇬🇧 · Yi-Zhuang You🇺🇸

    The local Lie algebra of the Standard Model (SM) is $su(3)\times su(2)\times u(1)$, yet its global gauge group, $G_{{\mathrm{SM}}_{\mathrm{q}}}=$SU(3)$\times$SU(2)$\times$U(1)/${\mathbb{Z}}_{\mathrm{q}}$, q$=1,2,3,6$ remains undetermined. Building on previous work on 4d anomalies and 5d cobordism invariants, we classify lower-dimensional invertible field theories (iFTs) or symmetry-protected topological states (SPTs) in 4d, 3d, 2d, and 1d. While the integer SPTs are hard to detect, the fractional SPTs produce measurable topological responses. In particular, the symmetry fractionalization labeled by $k\in {\mathbb{Z}}_{6/\mathrm{q}}$ in [arXiv:2411.18160] introduces the symmetry-enriched SM variants, denoted as SM${}_{(\mathrm{q},k)}$. We further introduce a new integer $n$ series of baryon-minus-lepton $(\mathbf{B}-\mathbf{L})$-like U(1) symmetries, $X_n\equiv n(\mathbf{B}-\mathbf{L})+(1-\frac{n}{N_c})\tilde{Y}$ with electroweak hypercharge $\tilde{Y}$, $n\ge 1$, $N_c=3$, where the charge $q_{X_n}=q_{\tilde{Y}}\mathrm{mod}n$. Analyzing the symmetry-enriched SM with 0-form and 1-form symmetries $(G_{[0]},G_{[1]})$, symmetry-twist group homomorphism $\rho$, and symmetry frationalization obstruction $[\beta ]$, their spacetime-internal gauge bundle constraints, and their mixed anomalies, we derive the fractional topological response ${\sigma }_n(\mathrm{q},k)=\frac{\mathrm{q}(1-n)\gcd (2,n)}{2n}+\frac{k\mathrm{q}}{6}\mathrm{mod}1.$ Our ${\sigma }_n$ response requires more general Spin${}^c$ manifolds for odd $n$ and Spin manifolds for even $n$. For a given $n$ (with $n\ge 7$ and $n\ne 10,12,15,30$), ${\sigma }_n$ uniquely fixes the gauge group parameter q and fractionalization label $k$. Moreover, using pairs such as $(n_1,n_2)=(2,3),(2,5),(3,4),(3,5),(4,5)$, etc. uniquely distinguishes SM${}_{(\mathrm{q},k)}$. Our results illuminate the global structure of the SM gauge group via measurable topological responses.

    ↳ hep-thcond-mat.str-elhep-ph8 citations
68. 68*

    Erratum: Exact solutions to the fermion propagator Schwinger-Dyson equation in Minkowski space with on-shell renormalization for quenched QED \newline [Phys. Rev. D 96, 036021 (2017)]

    Shaoyang Jia🇺🇸 · Michael R. Pennington

    With the introduction of a spectral representation, the Schwinger--Dyson equation (SDE) for the fermion propagator is formulated in Minkowski space in QED. After imposing the on-shell renormalization conditions, numeric solutions for the fermion propagator spectral functions are obtained in four dimensions with a renormalizable version of the Gauge Technique Ansatz for the fermion-photon vertex in the quenched approximation in the Yennie gauge. Despite the limitations of this model, having an explicit solution provides a guiding example of the fermion propagator with the correct analytic structure.

    ↳ nucl-thhep-ph0 citations
69. 69*

    Scattering of wave dark matter by supermassive black holes

    Giovanni Maria Tomaselli🇺🇸

    Recent simulations of wave dark matter around black hole binaries revealed the formation of a universal density profile that co-rotates with the binary. We derive this profile from first principles, interpreting it as the steady state of a scattering process. We find that the scattering becomes particularly efficient when the ratio of the binary separation to the dark matter's de Broglie wavelength assumes certain discrete values, which can be interpreted as bound state resonances. After estimating the amount of dark matter that undergoes this type of scattering off supermassive black hole binaries at galactic centers, we demonstrate that the process can induce an observable modification of the slope of the Pulsar Timing Array spectrum. This opens up a new possibility to gain insights on the nature of dark matter from observations of low-frequency gravitational waves.

    ↳ gr-qcastro-ph.COastro-ph.GAastro-ph.HE+1PRD(2025)·18 citations
70. 70*

    Towards the BBGKY hierarchy: a scheme beyond the Boltzmann equation and application to a weakly confined QCD gas

    Sašo Grozdanov🇬🇧 · Alexander Soloviev🇸🇮

    In classical kinetic theory, the BBGKY hierarchy is an infinite chain of integro-differential equations that describes the full time-reversal-invariant (Liouville) system of interacting (quasi)-particles in terms of $N$-particle distribution functions. In this work, instead of truncating the hierarchy at the lowest level, as is done by the Boltzmann equation, we develop a scheme similar to the relaxation time approximation that is in principle able to account for the entire chain of equations. We then explicitly investigate its truncation at the second level of the BBGKY hierarchy and, within this scheme, study the spectra of conserved operator correlation functions in a gas of weakly confined hadrons. We also discuss how these higher levels account for parts of the operator spectra `deeper in the ultra-violet regime' and compare them to known results derived from the holographic duality.

    ↳ hep-thcond-mat.stat-mechhep-ph7 citations
71. 71*

    Feynman Diagrams from Conformal Integrals

    Siddharth G. Prabhu🇮🇳

    We show that momentum space Feynman diagrams involving internal massless fields can be cast as conformal integrals. This leads to a classification of all Feynman diagrams into conformal families, labelled by conformal integrals. Computing the conformal integral in each family suffices to compute all the Feynman diagrams in the family exactly. Using known exact results for some conformal integrals, we present the solutions to the other Feynman diagrams in the corresponding families. These are answers to either finite or dimensionally regularized Feynman diagrams to all orders in the regularization parameter.

    ↳ hep-thhep-ph2 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.