Fri·Jun 6, 2025Friday·June 6, 2025

1. 01*

   Probing the electromagnetic structure of the $P_c(4337{)}^{+}$ pentaquark: Insights from a diquark-diquark-antiquark picture for $J^P={\frac{1}{2}}^{-}$ and ${\frac{3}{2}}^{-}$ states

   U. Özdem🇹🇷

   In this work, the electromagnetic structure of the hidden-charm pentaquark $P_c(4337)$ is investigated within the diquark-diquark-antiquark model using the QCD light-cone sum rule approach. The magnetic moments of the $P_c(4337)$ state are calculated for the spin-parity assignments $J^P={\frac{1}{2}}^{-}$ and ${\frac{3}{2}}^{-}$. The results are found to be ${\mu }_{P_c}=1.76\pm 0.44{\mu }_N$ for the ${\frac{1}{2}}^{-}$ case and ${\mu }_{P_c}=-1.38\pm 0.35{\mu }_N$ for the ${\frac{3}{2}}^{-}$ scenario. These findings offer important insights into the internal quark-gluon structure and electromagnetic features of this multiquark system. Beyond their theoretical relevance, the results serve as essential benchmarks for future experimental studies aimed at determining the quantum numbers and underlying configuration of the $P_c(4337)$. Additionally, the electric quadrupole and magnetic octupole moments of the spin-$\frac{3}{2}$ state are extracted, indicating a non-spherical charge distribution for this exotic pentaquark.

   hep-phEPJC(2025)·8 citations
2. 02*

   Dark Matter Induced Proton Decays

   Ranjeet Kumar🇮🇳 · Rahul Srivastava🇮🇳

   We propose a novel theoretical framework in which proton decay is induced by the dark matter. While proton decay requires violation of the $B+L$ symmetry, dark matter stability often relies on the presence of an unbroken symmetry. These seemingly distinct phenomena are unified through the global $U(1{)}_{B+L}$ symmetry inherent in the Standard Model. Its spontaneous breaking leads to a residual $Z_4$ symmetry, which ensures dark matter stability and forbids proton decay at tree level. Consequently, proton decay occurs at the one-loop level, mediated by dark sector particles. The proton lifetime is linked with the dark matter, the heavier dark matter mass enhancing proton stability, and vice versa. The $\mathcal{O}$(TeV) masses of the mediators remain consistent with current proton lifetime limits, making them accessible to experimental searches. In particular, the leptoquark mediating proton decay, carrying exotic $B+L$ charges, leads to a distinctive signature in collider searches. By intertwining proton decay, dark matter stability, and collider phenomenology, this framework offers distinctive signatures that can be probed in current and future experiments.

   hep-phgr-qchep-exJHEP(2026)·6 citations
3. 03*

   Setting up stasis with gravitational interactions

   Andrew J. Long🇺🇸 · Barmak Shams Es Haghi🇺🇸 · Moira Venegas🇺🇸

   An epoch known as cosmological stasis may have taken place in the early Universe. During matter-radiation stasis, a population of non-relativistic particles with different masses gradually decay into relativistic particles, and the effective equation of state $w$ remains approximately constant at a value between that of matter ($w=0$) and that of radiation ($w=1/3$). In this work, we investigate how to set up the appropriate initial conditions for stasis using gravitational interactions. We consider two scenarios: that the tower of non-relativistic particles is populated by the evaporation of primordial black holes (PBHs) and that the tower is populated by cosmological gravitational particle production (CGPP) during inflation. We calculate the abundance of particles on different levels of the tower to assess whether stasis is viable. We find that both scenarios can provide the needed initial conditions for stasis, and that they predict distinctive scaling exponents ${\Omega }_l\propto m_l^{\alpha }$ with mass $m_l$.

   hep-phJCAP(2026)·7 citations
4. 04*

   Reflections on Noether's second theorem and the energy-momentum tensor

   Adam Freese🇺🇸

   Through symmetry of the action under global spacetime translations, Noether's first theorem infamously entails an energy-momentum tensor (EMT) that is neither symmetric nor gauge-invariant. In a prior work [Phys. Rev. D 106, 125012 (2022)], I had obtained a symmetric and gauge-invariant EMT by using Noether's second theorem instead, with local spacetime translations as the symmetry group. However, the derivation therein was flawed, containing a faulty assumption about the transformation rule for spinor fields. In this work, I revisit the derivation of [Phys. Rev. D 106, 125012 (2022)], both correcting the faulty step and simplifying the derivation for broader accessibility. The end result is an EMT for quantum chromodynamics that is gauge-invariant, but not symmetric.

   hep-phgr-qcnucl-thPRD(2026)·7 citations
5. 05*

   Bounds and detection of MeV-scale dark matter annihilation to neutrinos

   Shinya Kanemura🇯🇵 · Shao-Ping Li🇯🇵 · Dibyendu Nanda🇯🇵

   Current and most upcoming neutrino detectors can only reach a dark matter annihilation cross section to neutrinos larger than the standard freeze-out value, but they open intriguing detection avenues for non-standard dark matter paradigms. An important corollary of these non-standard scenarios is relic dark matter annihilation after neutrino decoupling, which was previously overlooked in constraining MeV-scale dark matter. However, by combining the contributions from entropy injection during neutrino decoupling and from nonthermal neutrino energy release after decoupling, we derive significant constraints on the annihilation cross section to neutrinos, which in some mass regimes become stronger than the current bounds. Furthermore, we find that the lower bounds on dark matter masses become inconclusive under the recent data releases from the DESI, SPT-3G, and ACT collaborations. These bounds determine the extent to which upcoming neutrino detectors will probe dark matter annihilation into neutrinos.

   hep-phhep-exPRD(2025)·4 citations
6. 06*

   Probing Terrestrial Relic Neutrino Charge with Mach-Zehnder Interferometer

   Chuan-Ren Chen🇹🇼 · Chrisna Setyo Nugroho🇹🇼 · Vincent Gene L. Otero

   We propose a novel method to probe the cosmic neutrino background (CNB) which has been shown to be accumulated on the surface of the earth. If such relic neutrino carries non-zero electric charge, Mach-Zehnder interferometer offers a suitable venue to unveil its interaction with photons. For neutrino mass equals to 0.05 eV, the sensitivity reach of our proposal could probe the fractional electric charge of the neutrino ${ϵ}_{\nu }$ as low as $9.3\times 10^{-11},1.6\times 10^{-16}$, and $2.9\times 10^{-22}$ provided that the interferometer operates at standard quantum limit (SQL), the Heisenberg limit as well as super-Heisenberg limit, respectively.

   hep-phhep-ex3 citations
7. 07*

   Line shape analysis of $\Lambda (1405)$ in $\gamma p\to K^{+}{\Sigma }^{-}{\pi }^{+}$ reaction using convolutional neural network

   Vince Angelo A. Chavez🇵🇭 · Denny Lane B. Sombillo🇵🇭

   Interpreting peaks or dips that appear in an invariant mass distribution is a recurring challenge in hadron physics. These enhancements can be ambiguous, especially near a two-hadron threshold since kinematical and dynamical effects play an important role in their nature. One such enhancement is an exotic baryon $\Lambda (1405)$ which was first observed in 1973. Despite the few available experimental data, the statistics of the measurements of $\Lambda (1405)$ have improved for line shape analysis. The present consensus is that it is a structure of two poles both on the second Riemann sheet. However, there are still investigations of other pole structures corresponding to $\Lambda (1405)$. Lately, the use of a deep neural network in analyzing these line shapes has been proven to be effective, especially in distinguishing pole structures. Thus, in this study, we develop a convolutional neural network, a type of DNN, to determine the general pole structure that corresponds to $\Lambda (1405)$ found in the ${\Sigma }^{-}{\pi }^{+}$ invariant mass distribution measured by CLAS in their experiment involving the $\gamma p\to K^{+}\Sigma \pi$ reaction. The CNN is trained using a two-channel uniformized $S$-matrix allowing us to control the position and the corresponding Riemann sheet of the poles. Our preliminary results show that the trained CNN can accurately distinguish pole structures in the ${\Sigma }^{-}{\pi }^{+}$ invariant mass distribution and agrees with the present consensus of a two-pole structure. This supports the preceding works on the $\Lambda (1405)$ and requires a thorough analysis of ${\Sigma }^{+}{\pi }^{-}$ and ${\Sigma }^0{\pi }^0$ invariant mass spectra.

   hep-phhep-exPoS(2026)·2 citations
8. 08*

   Feature extraction in partial wave analysis using $K$-matrix approach

   Adam B. Mapa II · Denny Lane B. Sombillo🇵🇭

   Structures in the invariant mass distribution are often linked to unstable intermediate states or resonances. In experiments, many signals are detected which have broad, overlapping or intricate profiles, which makes their characterization a formidable task. To ascertain whether or not these enhancements are resonances, and to determine their physical parameters, such as the resonance mass, coupling strength, resonance width, and quantum numbers, a tool known as partial wave analysis (PWA) is employed. To ensure unitarity, and to account for superposing states and non-resonant effects in modeling the scattering amplitude, $K$-matrix parametrization is utilized. To factor in the centrifugal effects on the decay rates arising from breakup processes in nonzero angular momenta, the Blatt-Weisskopf barrier factors are incorporated into the formulation. In this study, $K$-matrix parametrized differential cross sections were generated within near-threshold and resonance energy ranges, which served as the training and validation datasets for the Deep Neural Network (DNN). The Fully-Connected Neural Network (FCNN) architecture is applied to facilitate the classification task of this work, which is the discrimination of dominating partial waves in the scattering processes. The DNN model was designed to encompass various two-hadron scattering phenomena. As a stepping-off point, the values of the thresholds, coupling constants, resonance masses and widths, scattering energy ranges, and the decay channels used in this study found their physical inspiration from pion-nucleon ($\pi$$N$) scattering system in the $S$, $P$, $D$, $F$, and $G$ partial waves. The results of the model's performance showed that the DNN can distinguish the partial wave with resonances from the other partial waves with purely non-resonant contributions, at an accuracy of $69\%$.

   hep-phhep-exPoS(2026)·1 citation
9. 09*

   Effects of closely spaced thresholds on line shapes with near-threshold enhancement

   Exan John D.F. Carpio · Denny Lane B. Sombillo🇵🇭

   Hidden-charm pentaquarks were first experimentally detected by LHCb in 2019, one of which is the exotic $P_{c\bar{c}}(4312{)}^{+}$ state. The nature of this state remains uncertain which may be attributed to the proximity of this observed enhancement to the meson-baryon thresholds. In this study, we introduce a coupled-channel approach using three-channel separable potential model to account for near-threshold effects on the observed signal. In particular, we assign ${\Sigma }_c^{+}{\bar{D}}^0$ and ${\Sigma }_c^{++}{D}^{-}$ as higher-mass channels for $P_{c\bar{c}}(4312{)}^{+}$ state. Moreover, this allows us to propose four pole configurations, where either a bound state or virtual state pole were placed near the higher-mass thresholds. Using this scheme, we study the near-threshold effects on the transition of different pole configurations across the unphysical Riemann sheets and examine their effects on the amplitude line shape. We found out that $P_{c\bar{c}}(4312{)}^{+}$ state may be interpreted as a virtual state below the ${\Sigma }_c^{+}{\bar{D}}^0$ which is consistent with our initial modeling assumptions. Our result also conforms with the previous analysis done by Joint Physics Analysis Center (JPAC) \cite{Fernandez-Ramirez:2019koa}, which leans toward similar interpretation. This may indicate that a model-dependent framework employing a relatively simple model, such as a separable potential, can somehow complement with some of the widely used parameterizations.

   hep-phPoS(2026)·0 citations
10. 10*

    Axion-mediated photon-to-photon transitions in high finesse dielectric resonators

    Evangelos Almpanis🇬🇷

    Axions are hypothetical particles that could address both the strong charge-parity problem in quantum chromodynamics and the enigmatic nature of dark matter. However, if axions exist, their mass remains unknown, and they are expected to interact very weakly with the electromagnetic field, which explains why they have not been detected yet. This study proposes a way to substantially augment the axion-photon interaction by confining the photons within high-quality-factor dielectric resonators, increasing their intensity and lifetime, and thus the possibility of interacting with axions in the background. In view of this, we study resonant axion-mediated photonic transitions in millimeter-sized spherical dielectric resonators, based on fully analytical calculations to the first order in perturbation theory. Such resonators exhibit high lifetime Mie resonances in the microwave part of the spectrum, with a separation that can be tailored with the radius of the sphere to match the expected axion frequency, allowing axion-mediated photonic transitions when particular selection rules are fulfilled. We predict experimentally accessible axion mass regimes where such triply resonant transitions can be realized with standard dielectric resonators. We propose an experiment for probing such interactions named DARK-ROSE.

    hep-phcond-mat.mtrl-scihep-thAPS Open Science(2026)·0 citations
11. 11*

    Dark matter and dark radiation from chiral $U(1)$ gauge symmetry

    Xiao He🇨🇳 · Takaaki Nomura🇨🇳 · Norimi Yokozaki🇨🇳

    We consider a simple model of a dark sector with a chiral $U(1)$ gauge symmetry. The anomaly-free condition requires at least five chiral fermions. Some of the fermions acquire masses through a vacuum expectation value of a Higgs field, and they are stable due to an accidental symmetry. This makes them dark matter candidates. If the dark sector was once in thermal equilibrium with the Standard Model and dark radiation constraints are included, two-component dark matter may be needed since the number of massless fermions is restricted. When the Dirac fermion is the main component of dark matter, the kinetic mixing should be around $10^{-6}$: a larger value is restricted by direct detection limits, while a smaller value prevents thermal freeze-out. If the main dark matter component is a Majorana fermion, the kinetic mixing can be larger. Still, a sub-component of Dirac fermion could produce a detectable signal in future direct detection experiments. We also discuss the possibility of testing an invisible dark photon at future lepton collider experiments, taking into account cosmological constraints.

    hep-phhep-exJHEP(2026)·2 citations
12. 12*

    Dark higher-form portals and duality

    Cypris Plantier🇫🇷 · Christopher Smith🇫🇷

    Light scalar or vector particles are among the most studied dark matter candidates. Yet, those are always described as scalar or vector fields. In this paper, we explore instead the embedding of the scalar particle in an antisymmetric rank-three tensor field, and the dark photon into an antisymmetric rank-two tensor field (a so-called Kalb-Ramond field), and construct minimal bases of effective interactions with Standard Model fields. Then, keeping phenomenological applications as our main objective, a number of theoretical aspects are clarified, in particular related to the impact of existing dualities among the corresponding free theories, and concerning their Stueckelberg representations. Besides, for the rank-two field, we present for the first time its full propagator, accounting for the possible presence of a pseudoscalar mass term. Thanks to these results, and with their different kinematics, gauge-invariant limits, and Lorentz properties, we show that these higher-form fields provide genuine alternative frameworks, with different couplings and expected signatures at low-energy or at colliders.

    hep-phhep-thPRD(2025)·3 citations
13. 13*

    Central exclusive production of $\eta$ and ${\eta }^{\prime }$ mesons in diffractive proton-proton collisions at the LHC within the tensor-pomeron approach

    Piotr Lebiedowicz🇵🇱 · Otto Nachtmann🇩🇪 · Antoni Szczurek🇵🇱

    We present a study of the central exclusive production (CEP) of $\eta$ and ${\eta }^{\prime }(958)$ mesons in diffractive proton-proton collisions at high energies. The amplitudes, including pomeron and $f_{2\mathbb{R}}$ reggeon exchanges, are calculated within the tensor-pomeron model. Absorption effects are also taken into account at the amplitude level. We fit some undetermined model parameters (coupling constants and cutoff parameters in form factors) to the WA102 experimental data and then make predictions for the LHC energy $\sqrt{s}=13$ TeV. Both, total cross sections and several differential distributions are presented. For $pp\to pp\eta$, we find an upper limit for the total cross section of 2.5 $\mu$b for pseudorapidity of the $\eta$ meson $|{\eta }_M|<1$ and 5.6 $\mu$b for $2<{\eta }_M<5$. For $pp\to pp{\eta }^{\prime }$, we predict the cross section to be in the range of 0.3-0.7 $\mu$b for pseudorapidity of the ${\eta }^{\prime }$ meson $|{\eta }_M|<1$ and 0.9-2.1 $\mu$b for $2<{\eta }_M<5$. This opens the possibility to study diffractive production of pseudoscalar mesons in experiments at the LHC. We discuss if there are arguments from SU(3)-flavor symmetry which would forbid pomeron-pomeron fusion giving an $\eta$ meson. In our opinion such arguments do not exist. We also consider CEP of the pseudoscalars $\eta$ and ${\eta }^{\prime }(958)$ and the pseudovector meson $f_1(1285)$ in diffractive proton-proton collisions in a theory with a scalar pomeron. We show that none of these particles can be produced in this way in the scalar-pomeron theory. Thus, experimental observation of any of these particles in the above CEP processes at the LHC would give striking evidence against a scalar character of the pomeron.

    hep-phhep-exPRD(2025)·3 citations
14. 14*

    Extended locally monochromatic approximations of Strong-Field QED processes

    Nikita Larin🇩🇪 · Daniel Seipt🇩🇪

    Strong-field QED (SFQED) probability rates in the locally monochromatic approximation (LMA) have become an indispensable tool for simulations of processes like gamma-ray emission or electron-positron pair production in laser-particle collisions. We revisit the LMA derivation and explicitly demonstrate that it is based on the separation of time scales, neglection of the long-range interference effects and subsequent averaging over the cycle scale. Doing so, we obtain unambiguously LMA rates for arbitrary polarizations of the plane wave background. Additionally, we partially restore the finite bandwidth effects that are lost in the LMA derivation. The bandwidth-restored result we refer to as the LMA${}^{+}$ and show that it agrees with the full SFQED predictions better than the standard LMA. We use LMA${}^{+}$ to address previously inaccessible observables and formulate a new limitation on the applicability of locally monochromatic approximations in general. We provide analytical results for the angular-integrated LMA${}^{+}$ probability rate and the fully differential probability that account for the finite bandwidth effects.

    hep-phphysics.plasm-phPRA(2025)·4 citations
15. 15*

    Non-perturbative determination of the sphaleron rate for first-order phase transitions

    Jaakko Annala🇫🇮 · Kari Rummukainen🇫🇮 · Tuomas V.I. Tenkanen🇫🇮

    In many extensions of the Standard Model electroweak phase transitions at high temperatures can be described in a minimal dimensionally reduced effective theory with SU(2) gauge field and fundamental Higgs scalar. In this effective theory, all thermodynamic information is governed by two dimensionless ratios $x\equiv {\lambda }_3/g_3^2$ and $y\equiv m_3^2/g_3^4$, where ${\lambda }_3$, $m_3^2$ and $g_3$ are the effective thermal scalar self-interaction coupling, the thermal mass and the effective gauge-coupling, respectively. By using non-perturbative lattice simulations to determine the rate of sphaleron transitions in the entire $(x,y)$-plane corresponding to the Higgs phase, and by applying previous lattice results for the bubble nucleation, we find a condition $x(T_c)\lesssim 0.025$ to guarantee preservation of the baryon asymmetry, which translates to $v/T_c\equiv \sqrt{2\Delta ⟨{\varphi }^{†}\varphi ⟩}/T_c\gtrsim 1.33$ for the (gauge-invariant) discontinuity in Higgs condensate. This indicates that viability of the electroweak baryogenesis requires the phase transition to be slightly stronger than previously anticipated. Finally, we present a general template for analysing such viability in a wide class of beyond the Standard Model theories, in which new fields are heavy enough to be integrated out at high temperature.

    hep-phastro-ph.COhep-latPRD(2026)·12 citations
16. 16*

    Toward an advanced phenomenology of $\pi N$ transition distribution amplitudes

    B. Pire🇫🇷 · K. Semenov-Tian-Shansky🇰🇷 · P. Sznajder🇵🇱 · L. Szymanowski🇵🇱

    We introduce a new approach to modeling transition distribution amplitudes (TDAs) for the processes $ep\to en{\pi }^{+}$ and $ep\to ep{\pi }^0$. The modeling is flexible, constrained by sparsely available experimental data, and satisfies theoretical requirements, including reduction to nucleon distribution amplitudes in the appropriate limit. We study the sensitivity of observable predictions to various modeling assumptions. We discuss unpolarized cross-sections, as well as the three non-vanishing polarization observables at leading twist, namely, the single transverse target spin asymmetry and the two double spin asymmetries that occur with a polarized lepton beam on either a longitudinally or transversely polarized target. The analysis is complemented by a simple Monte Carlo study to provide guidance for exploring exclusive processes in the so-called backward kinematics. Our work aims to highlight the importance of future measurements to better constrain TDAs and to support upcoming experimental proposals.

    hep-phhep-exnucl-exnucl-thPRD(2025)·3 citations
17. 17*

    Probing new physics scenarios using high energy events at NOvA far detector

    Chinmay Bera🇮🇳 · K. N. Deepthi🇮🇳

    NuMI Off-axis ${\nu }_e$ Appearance (NOvA) experiment is an ongoing long baseline neutrino oscillation experiment. The primary channels of interest are the ${\nu }_e$, ${\bar{\nu }}_e$ appearance, ${\nu }_{\mu }$, ${\bar{\nu }}_{\mu }$ disappearance channels analyzed in the energy window $1<E_{\nu }<4$ GeV. However, NOvA far detector sees non-trivial high energy ${\nu }_e$, ${\bar{\nu }}_e$ events in the energy range $4<E_{\nu }<20$ GeV. These high energy events provide us with an opportunity to investigate the subleading new physics scenarios. In this context, we study the sensitivity of the NOvA experiment to constrain the non-standard interaction (NSI) parameters and environmental decoherence. We observe that by including high energy events (signal + background) the degeneracy around ${ϵ}_{e\tau }\sim 1.6$ can be removed throughout the ${\delta }_{CP}$ and ${\delta }_{e\tau }$ range. Further, we examine the role of signal versus beam background events in removing this degeneracy. In addition, we constrain the decoherence parameter $\Gamma$ considering events from $1<E_{\nu }<20$ GeV. Later, assuming the presence of decoherence in nature we obtain the allowed regions in ${\theta }_{23}$ and ${\delta }_{CP}$ plane.

    hep-phPRD(2025)·2 citations
18. 18*

    Chiral perturbation theory for baryon-number-violating nucleon decay into a vector meson

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

    In a recent work [New chiral structures for baryon number violating nucleon decays, arXiv:2504.14855], we identified generic baryon-number-violating (BNV) structures containing triple light quarks and achieved their leading-order chiral realizations involving octet pseudoscalars and baryons. Although many two-body nucleon decays into a vector meson have been experimentally searched for and stringently constrained, a consistent theoretical framework for their calculation is still lacking. In this Letter, we fill the gap by implementing chiral matching of all these triple-quark interactions onto hadronic interactions involving octet vector mesons, baryons, and pseudoscalars. This paves the way for a consistent and comprehensive study of all relevant BNV processes. As an illustration of application, we show how degeneracy in the parameter space of Wilson coefficients can be broken by synthesizing experimental constraints on nucleon decays into a vector or pseudoscalar meson when relevant hadronic low-energy constants can be reasonably determined.

    hep-phPRD(2025)·7 citations
19. 19*

    Nonperturbative Parameters of Inclusive ${\Lambda }_b$ Decays from Small Velocity Sum Rules

    Blaženka Melić🇭🇷 · Ivan Nišandžić🇭🇷

    We investigate the nonperturbative parameters entering the heavy quark expansion for the inclusive decay rates of the ${\Lambda }_b$ baryon, focusing on the kinetic term ${\hat{\mu }}_{\pi }^2$ and the Darwin term ${\hat{\rho }}_D^3$. Recent evaluations have yielded an unexpectedly large Wilson coefficient associated with the dimension-six Darwin operator, which motivates a more detailed examination of the associated hadronic matrix element. We constrain ${\hat{\mu }}_{\pi }^2$ and ${\hat{\rho }}_D^3$ using Small Velocity Sum Rules for the inclusive semileptonic decay ${\Lambda }_b\to X_c{e}^{-}{\bar{\nu }}_e$. These sum rules relate moments of hadronic structure functions, computed via the Operator Product Expansion, to hadronic matrix elements of relevant exclusive transitions. Truncating the hadronic side to include the lowest-lying charmed baryon states with spin-parity $J^P=1/2^{+},1/2^{-},3/2^{-}$, we employ the corresponding lattice QCD form factors near zero recoil as inputs. By analysing zeroth and higher moments, we derive inequalities that define an allowed region in the $({\hat{\mu }}_{\pi }^2,{\hat{\rho }}_D^3)$ plane. The derived constraints are consistent, within uncertainties, with estimates from spectroscopic relations and the nonrelativistic constituent quark model. This work refines the determination of key HQE parameters for ${\Lambda }_b$, with implications for precision predictions of heavy baryon lifetimes and inclusive decays of heavy baryons in general.

    hep-phJHEP(2025)·1 citation
20. 20*

    SUSY meets SMEFT: Complete one-loop matching of the general MSSM

    Sabine Kraml🇫🇷 · Andre Lessa🇧🇷 · Suraj Prakash🇪🇸 · Felix Wilsch🇩🇪

    We present the complete one-loop matching of the Minimal Supersymmetric Standard Model (MSSM) onto the Standard Model Effective Field Theory (SMEFT), considering the most general case for the MSSM with conserved $R$-parity, which has 124 free parameters. The matching is performed with the Matchete package, which integrates out all superpartners at once with non-degenerate masses, while also retaining the most general flavor structure. Our results include all correlations among the different SMEFT Wilson coefficients that are governed by supersymmetry and thus provide a basis for future systematic and global studies of the MSSM parameter space employing EFT methods. A detailed discussion is provided on the treatment of the Higgs sector and electroweak symmetry breaking, along with the reduction of redundant operators in the EFT Lagrangian to the Warsaw basis. Furthermore, we validate against existing results in the literature and present a minimal phenomenological example. As an alternative low-energy scenario, we also provide the complete one-loop matching of the MSSM onto the two-Higgs-doublet-model EFT, where the second Higgs doublet is retained in the infrared spectrum. Extensive auxiliary material, including the code utilized for the matching, is available on GitHub.

    hep-phJHEP(2026)·8 citations
21. 21*

    Pion-Nucleon Scattering in Baryon Chiral Perturbation Theory combined with the $1/N_c$ Expansion

    D. Jayakodige🇺🇸 · J. L. Goity🇺🇸

    This work implements the combined BChPT and 1/Nc expansions for pion-nucleon elastic scattering. The effective theory is based on the baryon sector dynamical spin-flavor SU(4) symmetry emergent in the large Nc limit, whose breaking is controlled by the $1/N_c$ expansion. The non-commutativity of the chiral and 1/Nc expansions in unitarity corrections (loops) requires a linking of both expansions. As it was shown in the case of baryon masses and currents, the natural linking is the $\xi$-expansion, in which $O(p)=O(1/Nc)=O(\xi )A$. The spin-flavor symmetry requires that the ground state baryons span an SU(4) symmetric irreducible representation which implies that in particular $N$ and $\Delta$ are active degrees of freedom in the effective theory. The scattering amplitude is expanded to the next-to-next-to leading order in the $\xi$ expansion, corresponding to the one-loop contributions with the LO Lagrangian. The results are given for generic $N_c$ in order to demonstrate the consistency of the framework. The spin-flavor symmetry plays a central role in maintaining the consistency of the effective theory with respect to the $1/N_c$ expansion. This consistency manifests itself in an improvement in the convergence of the low energy expansion with respect to the case of the ordinary BChPT without an explicit dynamical $\Delta$, which is known to be inconsistent with the constraints of $N_c$ scaling. Fits to the $\pi N\to \pi N$ S, P and D partial wave amplitudes from the SAID data base are finally used to test the framework and to determine the energy range of its applicability.

    hep-phnucl-thPRD(2025)·1 citation
22. 22*

    2024 TASI Lectures: A Dark Matter Primer

    Tien-Tien Yu🇺🇸

    These notes are based on a sequence of 4 lectures delivered at the 2024 Theoretical Advanced Study Institute (TASI) and at the Università degli Studi di Padova. They are intended for graduate students at the early stages of their study of dark matter with some prior exposure to cosmology and quantum field theory. The primary aim is to offer an accessible introduction to dark matter and to lay the groundwork for exploring its phenomenology. These lectures are not intended to serve as a comprehensive review. We begin by motivating the study of dark matter through a discussion of the empirical evidence and the constraints it places on dark matter properties. This is followed by an overview of several canonical mechanisms for the production of cosmological dark matter, and a concluding section that surveys current experimental and observational efforts to detect it with a focus on direct detection.

    hep-phastro-ph.CO7 citations
23. 23*

    Closing in on singly charged scalars

    Snehadri Das🇺🇸 · Will Howe🇺🇸 · Brian Shuve🇺🇸 · David Tucker-Smith🇺🇸 · Ruby Yager🇺🇸

    We investigate current experimental constraints and future search prospects for a hypothetical spin-zero particle that carries unit electric charge: a singly charged scalar (SCS). In addition to providing useful benchmarks for collider searches, SCS particles are also well-motivated ingredients in relatively minimal dark sectors. We focus on scenarios in which the SCS decays promptly at colliders to a lepton plus either a neutrino or an invisible dark-sector particle of negligible mass. A promptly decaying SCS can easily have appreciable branching ratios to more than one lepton flavor while remaining consistent with constraints on lepton flavor violation. This broadens the allowed range of SCS masses to extend well beyond those for right-handed selectrons, smuons, or staus. For particular benchmark SCS branching ratios, we find that SCS masses above ~185 GeV and in a lower-mass window ~80-125 GeV are still allowed at 95% confidence level. We carry out Monte Carlo simulations to explore the potential of a boosted-decision-tree-based analysis to probe the surviving SCS parameter space in future searches at the (HL-)LHC, finding a significant increase in sensitivity relative to cut-based analyses both in the lower-mass window and at higher SCS masses.

    hep-phhep-exPRD(2025)·4 citations
24. 24*

    Searching for Hidden Sector Particles at Neutrino Telescopes

    Sagar Airen🇺🇸 · Zackaria Chacko🇺🇸 · Can Kilic🇺🇸 · Ram Purandhar Reddy Sudha🇺🇸

    We explore the possibility of directly detecting light, long-lived hidden sector particles at the IceCube neutrino telescope. Such particles frequently arise in non-minimal hidden sectors that couple to the Standard Model through portal operators. We consider two distinct scenarios. In the first scenario, which arises from a neutrino portal interaction, a hidden sector particle is produced inside the detector by the collision of an energetic neutrino with a nucleon, giving rise to a visible cascade. This new state then decays into a hidden sector daughter, which can naturally be long-lived. The eventual decay of the daughter particle back to Standard Model states gives rise to a second cascade inside the detector. This scenario therefore gives rise to a characteristic "double bang" signal arising from the two distinct cascades. In the second scenario, which arises from a hypercharge portal interaction, a hidden sector particle is produced outside the detector by the collision of an atmospheric muon with a nucleon. This new state promptly decays into a pair of hidden sector daughters that are long-lived. If both daughters decay into Standard Model states inside the detector, we again obtain a double-bang signal from the two distinct cascades. We explore the reach of IceCube for these two scenarios and show that it has the potential to significantly improve the sensitivity to hidden sector models in the mass range from about a GeV to about 20 GeV.

    hep-phhep-exPRD(2025)·5 citations
25. 25*

    Momentum fraction and hard scale dependence of double parton scattering

    Joao Vitor C. Lovato🇧🇷 · Edgar Huayra🇧🇷 · Emmanuel G. de Oliveira🇧🇷

    The effective cross section of double parton scattering in high-energy hadron collisions has been measured in proton--proton collisions, with significant variation among final-state observables, contrary to the idea of a universal value. Building upon our previous work, we incorporate the dependence on both the parton longitudinal momentum fraction $x$ and the process energy hard scale $\mu$ into the transverse part of the double parton distributions, using a Gaussian profile. Employing the experimental data from the LHC and Tevatron experiments (covering different processes, kinematic configurations, and center--of--mass energies), we perform a global fit of the model, extracting the parameters that describe the proton structure. With this result, it becomes possible to calculate the effective cross section for others observables, and we provide predictions for future measurements at the LHC.

    hep-phJHEP(2025)·4 citations
26. 26*

    Quantum pions

    M. Fabbrichesi🇮🇹 · R. Floreanini🇮🇹 · E. Gabrielli🇮🇹 · L. Marzola🇪🇪

    We show that two- and three-pion states produced in the decay of neutral kaons are contextual, entangled, and Bell nonlocal in isospin space. By reinterpreting the experimental values of the different isospin amplitudes, we can determine the amount of entanglement enjoyed by these states and the extent to which they violate the non-contextuality and Bell locality inequalities. Notably, the three-pion state offers a genuine multipartite test of Bell nonlocality with qutrits.

    hep-phhep-exquant-phPRD(2025)·9 citations
27. 27*

    Topological Freeze-out by Semi-Annihilation

    Joe Davighi🇨🇭 · Serah Moldovsky🇺🇸 · Hitoshi Murayama🇺🇸 · Christiane Scherb🇺🇸 · Nudzeim Selimovic🇮🇹

    We point out that a QCD-like dark sector can be coupled to the Standard Model by gauging the topological Skyrme current, which measures the dark baryon number in the infrared, to give a technically natural model for dark matter. This coupling allows for a semi-annihilation process $\chi \chi \to \chi X_{\mu }$, where $X_{\mu }$ is the gauge boson mediator and $\chi$ a dark pion field, which plays the dominant role in setting the dark matter relic abundance. The topological interaction is purely $p$-wave and so free from indirect detection constraints. We show that the dark matter pion mass needs to be in the range $10$ MeV $\lesssim m_{\chi }\lesssim$ $1$ TeV; towards the lighter end of this range, there can moreover be significant self-interactions. We discuss prospects for probing this scenario at collider experiments, ranging from the LHC to low-energy $e^{+}{e}^{-}$ colliders, future Higgs factories, and beam-dump experiments.

    hep-phJHEP(2026)·14 citations
28. 28*

    The Intrinsic and Extrinsic Hierarchy Problems

    James D. Wells🇺🇸

    The Hierarchy Problem of elementary particle physics can be divided into two separate problems: the Intrinsic and Extrinsic Hierarchy Problems. The Intrinsic Hierarchy Problem (IHP) arises when the Wilsonian renormalization group induces a large ${\Lambda }_{\mathrm{UV}}^2$ cutoff dependence on a much lighter scalar mass, creating a large finetuning. The Extrinsic Hierarchy Problem (EHP) arises when the IR theory is augmented with generically assumed extra states and interactions in the UV, making the resulting IR effective theory appear highly finetuned. The IHP is straightforward to analyze within a theory, but has suspicious regulator dependence, which has been suggested by some to be indication of a faux problem. The EHP is less straightforward to analyze, but has strength of physical intuition. We analyze EHP as a formal paradox, spelling out its premises and reasoning. From this we classify solutions to the EHP in terms of premise violations, and we articulate why some purported solutions to the Hierarchy Problem only partially solve the IHP and leave the EHP unaddressed.

    hep-phFound.Phys.(2026)·8 citations
29. 29*

    The quark-gluon plasma: diagnosis with thermal hadron production from the early history until detailed characterization at high energy colliders

    Peter Braun-Munzinger🇩🇪 · Krzysztof Redlich🇵🇱 · Johanna Stachel🇩🇪

    In nuclear collisions at relativistic energies, matter is created which resembles closely the matter that filled all space until about 15 microseconds after the big bang. Here we summarize selected aspects of the research that led to the establishment of this new sub-field of physics and briefly describe its current `state of the art' with emphasis on matter creation through thermal particle production. In particular, we will focus on particle production at low transverse momentum and explain how its analysis sheds light on one of the key open questions, i.e. what is the mechanism of hadronization of colored objects such as quarks and gluons.

    ↳ nucl-thhep-exhep-phnucl-ex3 citations
30. 30*

    Probing Ultralight Axion-like Dark Matter: A Pulsar Timing Arrays-Pulsar Polarization Arrays Synergy

    Ximeng Li🇨🇳 · Yonghao Liu🇨🇳 · Zu-Cheng Chen🇨🇳 · Shi Dai🇨🇳 · Boris Goncharov🇮🇹 · Xiao-Song Hu🇨🇳 · Qing-Guo Huang🇨🇳 · Tao Liu🇨🇳 · Jing Ren🇨🇳 · Yu-Mei Wu🇨🇳 · Xiao Xue🇪🇸 · Xingjiang Zhu🇨🇳

    Ultralight axionlike dark matter (ALDM) is a leading candidate in the dark matter realm, characterized by its prominent wave properties on astronomical scales. Pulsar timing arrays (PTAs) and Pulsar polarization arrays (PPAs) aim to detect this dark matter through timing and polarization measurements, respectively, of pulsars. The PTA relies on gravitational effects, while the PPA detects nongravitational effects. These two methods complement each other, synergistically enhancing the pulsar array's capability to identify the ALDM signals in the data. In this article, we provide a foundational development of this synergy. We begin by revisiting previously derived two-point correlation functions for both PTA and PPA, and extend the analysis to include the leading-order correlation between timing and polarization signals, encoded as a three-point function. We then explore the constructions of likelihood functions for PTA and combined PTA-PPA analyses within a Bayesian framework, aimed at detecting the characteristic correlations of ALDM signals. We emphasize the non-Gaussianity of the ALDM timing signals, which arises from their nonlinear dependence on the field, in contrast to the Gaussian nature of its polarization signals. To address the complexities introduced, we approach this investigation in two ways: one involves a Gaussian approximation with proper justifications, while the other derives the formalism from the generic Gaussian characteristics of the ALDM field. Particularly, for the combined PTA-PPA case, a clear connection between the three-point correlation function and the likelihood is established. We anticipate that these efforts will lead to further developments in PTA and PTA-PPA analysis methods, better accounting for the influence of non-Gaussianity.

    ↳ astro-ph.COastro-ph.HEhep-phPRD(2026)·11 citations
31. 31*

    On internal mechanical properties of Electroweak Magnetic Monopoles and their effects on stability

    K. Farakos🇬🇷 · G. Koutsoumbas🇬🇷 · Nick E. Mavromatos🇬🇷 · Alexandros Zarafonitis🇬🇷

    By considering properties of the energy-momentum tensor of the electroweak magnetic monopole and its Born-Infeld extension, we attempt to make comments on the stability of these configurations. Specifically, we perform a study of the behaviour of the so-called internal force and pressure of these extended field-theoretic solitonic objects, which are derived from the energy-momentum tensor. Our method is slightly different from the so-called Laue's criterion for stability of nuclear matter, a local form of which had been proposed and applied in the earlier literature to the `t Hooft-Polyakov (HP) magnetic monopole, and found to be violated.By applying our method first to HP monopole, we also observe that, despite its topological stability, the total (finite) internal force (which has only radial components) is directed inwards, towards the centre of the monopole, which would imply instability. Thus this mechanical criterion for stability is arguably violated in the case of the HP monopole, as is the local version of Laue's criterion. The criterion is satisfied for the short-range part of the energy momentum tensor, in which the long-range part, due to the massless photon of the U(1) subgroup, is subtracted. Par contrast, the total internal force of the Cho-Maison (CM) electroweak monopole has both radial and angular components, which diverge at the origin, leading to rotational instabilities. Finally, by studying finite-energy extensions of the CM, either with non-minimal Higgs couplings with the hypercharge sector or hypercharge Born-Infeld type models, we find that the total force, integrated over space, is finite, but it has also angular components in the Born-Infeld case. The latter feature is interpreted as indicating that the Born-Infeld-CM monopole might be subject to rotations upon the action of perturbations, but it does not necessarily imply instabilities of the configuration.

    ↳ hep-thhep-ph5 citations
32. 32*

    Can Gravitational Wave Data Shed Light on Dark Matter Particles ?

    Parthasarathi Majumdar🇮🇳

    Gravitational wave (GW) data from observed binary black hole coalescences (BBHC) have been demonstrated in recent analyses to validate the Hawking Area Theorem (HAT) for black hole horizons. The result of such analyses is imposed here as a criterion of {\it absolute} consistency on the logarithmic (in horizon area) corrections to the Bekenstein-Hawking Area Formula (BHAF) for the black hole entropy, when these corrections are computed both from non-perturbative quantum fluctuations of spacetime in matter-free quantum general relativity, as well as arising due to perturbative quantum matter field fluctuations around a stationary classical black hole background spacetime. This criterion of absolute consistency is seen to be obeyed provided certain restrictions ensue on the spin-parity and number of species of the spectrum of quantum matter fluctuations. Such constraints appear to restrict the Beyond-Standard-Model (BSM) part of the matter fluctuation spectrum. Some species of the constrained, yet-unobserved BSM particle spectrum are currently under active consideration in particle cosmology as candidates for dark matter.

    ↳ gr-qchep-phhep-thPRD(2026)·1 citation
33. 33*

    Gauge-invariant field strengths in $QCD$

    Adriano Di Giacomo🇮🇹

    Gauge-invariant field strengths, defined as parallel transports to infinity of ordinary field strengths, naturally emerge in a few physical phenomena governed by $QCD$. One of them is confinement of colour. Despite the arbitrariness in their definition coming from the freedom in the choice of the path of the parallel transport to infinity, the request of differentiability with respect to the position $x$ strongly constrains their correlation functions. Strong constraints also come from translation and Lorentz invariance. Gauge invariant field strengths also appear in the non abelian Stokes theorem, and allow to understand basic properties of the vacuum by use of lattice data.

    ↳ hep-lathep-phhep-th0 citations
34. 34*

    Mapping Parton Distributions of Hadrons with Lattice QCD

    Huey-Wen Lin🇺🇸

    The strong force which binds hadrons is described by the theory of quantum chromodynamics (QCD). Determining the character and manifestations of QCD is one of the most important and challenging outstanding issues necessary for a comprehensive understanding of the structure of hadrons. Within the context of the QCD parton picture, the parton distribution functions (PDFs) have been remarkably successful in describing a wide variety of processes. However, these PDFs have generally been confined to the description of collinear partons within the hadron. New experiments and facilities provide the opportunity to additionally explore the three-dimensional structure of hadrons, which can be described by generalized parton distributions (GPDs), for example. In recent years, a breakthrough was made in calculating the Bjorken-$x$ dependence of PDFs in lattice QCD by using large-momentum effective theory (LaMET) and other similar frameworks. The breakthrough has led to the emergence and rapid development of direct calculations of Bjorken-$x$--dependent structure. In this review article, we show some of the recent progress made in lattice QCD in PDFs and GPDs and discuss future challenges.

    ↳ hep-lathep-phnucl-thPPNP(2025)·28 citations
35. 35*

    Diffeomorphism invariance of the effective gravitational action

    Carlo Branchina🇮🇹 · Vincenzo Branchina🇮🇹 · Filippo Contino🇮🇹 · Riccardo Gandolfo🇮🇹 · Arcangelo Pernace🇮🇹

    We investigate on the diffeomorphism invariance of the effective gravitational action, focusing in particular on the path integral measure. In the literature, two different measures are mainly considered, the Fradkin-Vilkovisky and the Fujikawa one. With the help of detailed calculations, we show that, despite claims to the contrary, the Fradkin-Vilkovisky measure is diffeomorphism invariant, while the Fujikawa measure is not. In particular, we see that, contrary to naive expectations, the presence of $g^{00}$ factors in the Fradkin-Vilkovisky measure is necessary to ensure the invariance of the effective gravitational action. We also comment on results recently appeared in the literature, and show that formal calculations can easily miss delicate points.

    ↳ hep-thgr-qchep-phPRD(2025)·9 citations
36. 36*

    Anomalous dimensions at small spins

    A. N. Manashov🇩🇪 · S. Moch🇩🇪 · L. A. Shumilov🇩🇪

    In perturbation theory, the anomalous dimensions of twist-two operators have poles at negative or small positive integer values of spin and therefore must be resummed at these points. It was observed earlier that a certain quadratic combination of the anomalous dimensions remains finite at the right-most singularities, providing an efficient tool for resummation. In this paper, we analyze the small-spin behavior of the anomalous dimensions for all types of twist-two operators in the $O(N)$-symmetric ${\phi }^4$ model at the four-loop level, in the complex ${\phi }^3$ model at the three-loop level, and the Gross-Neveu-Yukawa model at the two-loop level. We find that the behavior of the anomalous dimensions at singular points is consistent with theoretical expectations, and we present expressions for the resummed anomalous dimensions.

    ↳ hep-thhep-phJHEP(2025)·7 citations
37. 37*

    Tidal Disruption in Topological Solitons and the Emergence of an Effective Horizon

    Pierre Heidmann🇺🇸 · Gela Patashuri🇺🇸

    We compute the dynamics of particles and strings falling into smooth horizonless spacetimes that match the Schwarzschild black hole but replace its horizon with a smooth cap in supergravity. The cap consists of a regular topological structure formed by the deformations of extra compact dimensions. We show that infalling particles follow Schwarzschild-like trajectories down to the cap, but experience rapidly growing tidal forces that reach extreme values. In addition, infalling strings encounter a region of tidal instability localized at the cap, where transverse modes are excited. This stringy excitation drains their kinetic energy, resulting in tidal trapping. We demonstrate that the onset and strength of this instability depend sensitively on the Kaluza-Klein scale, the string scale, and the mass of the spacetime, ensuring that strings cannot escape the cap region. These results show that horizonless geometries can reproduce key features of black hole absorption while maintaining regularity at the horizon scale, offering compelling evidence for the emergence of effective horizon-like behavior from topological spacetime structures.

    ↳ hep-thgr-qchep-phPRD(2025)·5 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.