HEP Phenomenology·hep-ph

Mon·Jun 15, 2026Monday·June 15, 2026

36 papers—24 primary·12 cross-listed

01
Dynamical Mass Growing of Fermion with Bare Mass in Two Dimensions
Toyoki Matsuyama🇯🇵
We study dynamical mass generation of a fermion with and without a bare mass by coupling with a massive vector field in two-dimensional space-time. To estimate a non-perturbative effect on the fermion mass, we employ the Schwinger-Dyson equations in the lowest-ladder approximation, which are solved by an approximated analytical method and also by a numerical method. We define a purely dynamical mass as a remnant after subtracting the bare mass from a total dynamical mass. We clarify dependence of the purely dynamical mass on the bare mass of the fermion in various region of a coupling constant. Especially we find that the purely dynamical masses growing from the different bare masses coincide with each other at a specific value of the coupling constant where a kind of a duality relation on the bare masses is satisfied.
hep-phhep-th0 citations
02
Conformal calibration and look-elsewhere effect in anomaly detection for new-physics searches
Jack Y. Araz🇬🇧 · Michael Spannowsky🇩🇪
Machine-learned anomaly detection is reshaping searches for new physics, but it has outrun the statistics used to interpret it. A raw anomaly score has no calibrated meaning, a model that scans many regions inflates the look-elsewhere effect, and the asymptotic significances the field relies on are blind to the background mismodelling that anomaly detectors are especially prone to. We propose a calibration layer, built on conformal prediction, that turns any anomaly score into a defensible significance with distribution-free, finite-sample guarantees. Conformal prediction converts scores into valid local p-values, weighted and Mondrian variants repair the sideband-to-signal-region exchangeability failures that resonant searches suffer, and a Gross-Vitells step carries the result through to a look-elsewhere-aware global significance. The layer does two things at once. It exposes miscalibration that the standard pipeline cannot see, and it corrects it without retraining the detector. On public LHC Olympics data, a classifier develops a substructure-mass correlation that makes sideband-calibrated background p-values anti-conservative. Taken at face value, this manufactures a $\sim 46 σ$ excess from background sculpting alone, which the label-free weighted correction removes, restoring an honest null. When run as a blind wide-mass bump hunt, the standard asymptotic and unweighted procedures fabricate $≳ 10 σ$ excesses and $\approx 5 σ$ excesses even in signal-free windows, while the conformal layer raises no false alarms and its global false-positive rate is verified on background-only pseudoexperiments. The result is an auditable, detector-agnostic path from an uncalibrated score to a trials-factor-aware significance, ready to be folded into experimental anomaly searches.
hep-phcs.LGhep-exstat.ML2 citations
03
Probing New Degrees of Freedom with the Universal Tail of Primordial Black Hole Mass Functions
Kaustubh Agashe🇺🇸 · Jae Hyeok Chang🇺🇸 · Steven J. Clark🇺🇸 · Bhaskar Dutta🇺🇸 · Yuhsin Tsai🇺🇸 · Tao Xu🇺🇸
The primordial black hole (PBH) mass function today develops a low-mass evaporation tail whose shape is universal with respect to the initial PBH mass distribution. This universality is fixed by the continuity equation and the Hawking mass-loss rate, but the tail is distorted if additional particle degrees of freedom participate in Hawking evaporation. Since this tail controls high-energy PBH photon emission, such distortions leave characteristic features in the gamma-ray spectrum. We show that these features provide a robust probe of new degrees of freedom, even for subdominant PBHs, within reach of future experiments and independent of visible-sector couplings or relic abundance.
hep-phastro-ph.COastro-ph.HE0 citations
04
Anomalies, Topology, and Hadron Structure in QCD
Ismail Zahed🇺🇸
Quantum Chromodynamics (QCD) provides a remarkable realization of how quantum effects reshape the symmetries of a classical field theory. The axial anomaly links chirality to gauge-field topology and underlies the resolution of the $U (1)_{A}$ problem, while the trace anomaly generates the intrinsic QCD scale through dimensional transmutation and accounts for most of the mass of hadrons and hence visible matter. Together, these quantum effects reveal the central role of gluonic dynamics and vacuum structure in strong-interaction physics. In this review, we discuss the theoretical foundations and physical consequences of anomalous symmetry breaking in QCD. We examine anomalous Ward identities, the topological structure of gauge fields, instantons, topological susceptibility, and the realization of chiral and scale symmetries in the QCD vacuum. We review their role in the generation of hadron masses, the $η^{'}$ mass, and the resolution of the $U (1)_{A}$ problem, and discuss their manifestations in polarized deep inelastic scattering, nucleon spin structure, and modern studies of hadron structure. Particular emphasis is placed on recent developments connecting vacuum topology, the flavor-singlet axial charge, topological screening, and the proton spin problem. Our aim is to provide a unified perspective on how quantum anomalies connect vacuum structure, hadron properties, and partonic observables, bridging nonperturbative dynamics and perturbative QCD.
hep-phhep-thnucl-th1 citation
05
Probing the $G (3900)$ State in Heavy-Ion Collisions
Luciano M. Abreu🇧🇷 · Pedro Brandão🇧🇷 · Rodrigo O. Magalhães🇧🇷 · Fernando S. Navarra🇧🇷
We investigate the interactions of the recently confirmed exotic hadron $G (3900)$ with the hadronic medium composed of light mesons produced in heavy-ion collisions. Using an effective Lagrangian approach, we compute both vacuum and thermally averaged cross sections for processes such as $G (3900) + π \to D^{(*)} + D ˉ^{(*)}$ and their inverse reactions. Following recent proposals, the $G (3900)$ is interpreted as a $P$ -wave $D D ˉ^{*} / D^{*} D ˉ$ molecular state. The resulting thermally averaged cross sections are employed in a rate equation to determine the time evolution of the $G (3900)$ multiplicity, with initial conditions provided by statistical and coalescence hadronization models. We compute the number of $G (3900)$ 's produced in central Pb-Pb collisions at $s_{N N} = 5.02$ TeV and compare it with the number of produced $Z_{c} (3900)$ 's . We obtain a considerably smaller final yield of $G (3900)$ compared to $Z_{c} (3900)$ .
hep-ph0 citations
06
A Model-Independent Approach to First-Order Phase Transitions, Gravitational Waves, and Primordial Magnetic Fields
Fayez Abu-Ajamieh🇮🇳 · Nobuchika Okada🇺🇸
We employ a model-independent Effective Field Theory (EFT) to analyze the possibility of a strong First-Order Phase Transition (FOPT) in extensions Beyond the Standard Model (BSM). We find that sizable deviations in the Higgs cubic and quartic interactions that are still allowed experimentally could lead to a strong FOPT, whereas the Higgs interactions to the top quark yield a weak FOPT. We also study the Gravitational Wave (GW) power spectra corresponding to the strong FOPT and find that they could be detectable in future experiments. In particular, we find that deformations of the Higgs quartic coupling have the dominant impact on the FOPT, with a GW signal that could be probed by a number of future experiments, such as LISA, BBO, and DECIGO. We also study the magnetic field produced by the corresponding FOPT and find that it could explain the primordial magnetic field puzzle. We find that for the size of deformations that could induce a strong FOPT, a scale of NP can be as low as $\sim 4 - 5 TeV$ for deformations in the Higgs cubic coupling, and $\sim 9 - 11 TeV$ for deformations in the Higgs quartic coupling. This highlights the synergy between collider searches and GW experiments in probing the Higgs couplings, specifically the Higgs quartic coupling.
hep-ph0 citations
07
From DUNE Sensitivities to UV Models: Implications of Flavour Constraints
Adriano Cherchiglia🇧🇷
Future neutrino experiments, in particular DUNE, are expected to probe signals of new physics. These effects can be conveniently parametrized in terms of Wilson coefficients in the LEFT, with direct connection to non-standard interactions at production, propagation and detection in the QFT formalism. We revisit the apparent sensitivity of DUNE to semileptonic electron--tau interactions within the Standard Model Effective Field Theory. We show that the vector combination controlling the $ϵ_{e τ}$ NSI is precisely the combination entering $τ \to e ω$ . Therefore, within the dimension-six vector subspace considered in this work, an operator cancellation that suppresses the tau-decay amplitude also suppresses the corresponding NSI. As a concrete example, we focus on the lepton-flavour-violating semileptonic coefficient $(C_{ℓ q, 1311}^{(1)})$ . We find the bound $8.1 \times 1 0^{- 3} TeV^{- 2}$ at $90%$ confidence level, which is one order of magnitude stronger than the DUNE's expected sensitivity. In view of this scenario, we further study one illustrative minimal UV completion, showing that it faces even stronger constraints from other sources, making it very challenging to build UV scenarios with heavy mediators that could produce flavour-changing NSIs observable at DUNE.
hep-ph0 citations
08
Meson molecules in strong magnetic fields: non-monotonic evolution of the charged pion and kaon energies
Toru Kojo🇯🇵
In strong magnetic fields, charged quarks occupy the lowest Landau level, leading to an effective dimensional reduction of hadronic dynamics. This dimensional reduction naturally generates a hierarchy of scales, separating fast intra-meson quark dynamics from slow collective meson motion; this motivates a Born-Oppenheimer description of meson-meson systems. Our Born-Oppenheimer analysis shows that the infrared behavior is controlled by the interplay between dimensional reduction and the structure of the meson-meson interaction, leading to three distinct regimes: scattering-dominated, molecular, and compact multiquark states. Charged pseudoscalar mesons such as $π_{+}$ and $K_{+}$ provide a particularly interesting realization of this framework, as their lattice spectra at large magnetic fields suggest the emergence of loosely bound states near the boundary between scattering and molecular regimes. Our results suggest that strong magnetic fields provide a useful laboratory for exploring the emergence and classification of hadronic bound states.
hep-phhep-latnucl-th1 citation
09
Quality control for axions and ALPs
Andrew Cheek🇨🇳 · Andrew Fowlie🇨🇳 · Gonzalo Herrera🇺🇸
Axions and axion-like particles (ALPs) are protected by Peccei-Quinn (PQ) symmetries that quantum gravity is expected to break. Modeling quantum gravity by Planck-suppressed PQ-breaking operators with unsuppressed Wilson coefficients and random phases, we quantify the fine-tuning required for an acceptable strong CP phase or a given ALP mass. For the QCD axion to account for the observed dark matter abundance at $f_{a} ≃ 1 0^{11} GeV$ , PQ-breaking operators must be absent up to mass dimension $D ≳ 12$ . We show that the residual strong CP phase could be measurable in upcoming neutron electric dipole moment searches. For ALPs, we map the mass-decay constant plane by the degree of UV protection required, and find that parts of the parameter space targeted by future laboratory experiments are already fine-tuned at the part-per-million level or worse, or equivalently, require PQ quality to be protected up to dimension $D ≫ 10$ . We argue that quality, not mass alone, is the central naturalness question for the axion program.
hep-ph2 citations
10
Thermal dileptons to probe the baryon-rich QCD matter in the forward region of LHC energy heavy-ion collisions
Motomi Oya🇯🇵 · Nicholas J. Benoit🇯🇵 · Chiho Nonaka🇯🇵 · Azumi Sakai🇯🇵 · Yorito Yamaguchi🇯🇵
We investigate thermal dilepton production from a quark-gluon plasma (QGP) with finite baryon chemical potential ( $μ_{B}$ ) in central Pb-Pb collisions at $s_{NN} = 5.02 TeV$ . Recent studies suggest that sizable baryon densities can be achieved at forward rapidity even at LHC energies. We incorporate finite $μ_{B}$ into a (3+1)-dimensional hydrodynamic framework and find that $μ_{B}$ exceeds 500 MeV around $η_{s} = 6$ during the medium evolution. Using this framework, we calculate thermal dilepton spectra over a wide rapidity range and evaluate the impact of finite $μ_{B}$ on dilepton production. A suppression of 3-4% is observed in the forward-rapidity region $5.2 < y < 7.2$ due to the reduced quark-antiquark abundance at finite baryon density. We further examine the effective temperature extracted from dilepton mass spectra in the intermediate-mass region $1.2 < M_{ℓℓ} < 2.6 GeV$ . The effective temperature remains strongly correlated with the underlying hydrodynamic temperature and retains sensitivity to the early high-temperature stage of the QGP evolution. These results demonstrate that forward-rapidity dileptons remain effective thermometers while providing sensitivity to finite baryon density at the LHC.
hep-phhep-exnucl-th0 citations
11
Small x dynamics of the unpolarised color dipole gluon TMD PDFs for all transverse momenta
Mariyah Siddiqah🇮🇳 · Nahid Vasim🇮🇳 · Mushood Nabi🇮🇳
A general solution of the Balitsky Kovchegov (BK) equation well describes the partonic behavior within the saturation regime and beyond this limit. This solution can potentially define the unpolarized color dipole gluon transverse momentum dependent (TMD) distribution in the small x regime for full k perp range. In this work, we Fourier-Bessel transform this general S matrix of the BK equation and, within the leading logarithmic approximation, obtain a closed form expression of unpolarised Gluon TMD. The distribution exhibits a smooth and well behaved k perp dependence from low to high transverse momenta. Numerical evaluation for different values of x accessible at the Electron Ion Collider (EIC), shows a characteristic inversion of the x ordering at the saturation scale. The result is in close agreement with the behavior observed in the unintegrated color dipole gluon distribution computed within the Bartels Golec Biernat Kowalski (BGK) model, suggesting that this feature is a model independent signature of gluon saturation.
hep-ph0 citations
12
Testing varying coupling constants through multi-Higgs production at the LHC
Ulf Danielsson🇸🇪 · Rikard Enberg🇸🇪 · Gunnar Ingelman🇸🇪 · Soumyadip Kundu🇮🇳 · Tanumoy Mandal🇮🇳 · Subhadip Mitra🇮🇳
We propose the One Scalar Theory (1ST), a minimalist framework where a single real singlet scalar field mediates the dynamical generation of the Higgs self-coupling and the top Yukawa coupling. Unlike generic portal models, the 1ST removes parametric freedom by locking production and decay modes to a single fundamental scale $Λ_{0}$ , rendering the framework highly predictive with unique experimental signals. We demonstrate that the collider phenomenology is partitioned by the $2 m_{t}$ kinematic threshold into di-Higgs and di-top resonance regimes. By recasting current ATLAS data, we set lower bounds on $Λ_{0}$ at the TeV scale and show that the High-Luminosity LHC will probe this scale up to $4$ TeV, providing a definitive test for the dynamical origin of the electroweak sector.
hep-phhep-ex0 citations
13
Light-front transverse profiles of scalar and spin-two chromoelectric EMT responses in near-threshold charmonium probes
Arkadiy I. Syamtomov🇺🇦
I construct light-front transverse profile functions for the scalar and spin-two chromoelectric energy-momentum-tensor responses selected by compact-charmonium probes of the proton. The scalar branch is the anomaly and sigma amplitude, while the spin-two branch contains the gravitational combination $3 B_{i} (t) - D_{i} (t) = 6 J_{i} (t) - 3 A_{i} (t) - D_{i} (t)$ rather than $A_{i} (t)$ alone. In the Drell-Yan frame, these two amplitudes define normalized transverse response profiles whose integrated ratio reproduces the forward light-front spin-two/scalar strength, while the finite transverse-distance behavior is sensitive to the relative scalar and gravitational slopes. The construction gives a spatial representation of the chromoelectric EMT projection without interpreting a measured near-threshold slope as a model-independent static three-dimensional mass radius.
hep-phPLB(2026)·1 citation
14
On Compositeness of $D_{s 0}^{*} (2317)$ and its decay to $D_{s} π^{0}$
Yu-Hui Zhou🇨🇳 · Xiu-Li Gao🇨🇳 · Bin Wu🇨🇳 · Jun-Xi Cui🇨🇳 · Zhi-Yong Zhou🇨🇳
We demonstrate that the $D_{s 0}^{*} (2317)$ can be described as a bound-state pole arising from the coupling between a discrete $c s ˉ (1^{3} P_{0})$ state and the $D K$ continuum state in the Lee-Friedrichs model. The elementariness and compositeness of the $D_{s 0}^{*} (2317)$ are determined to be about $Z : X \approx 51.1% : 48.9%$ , indicating a nearly equal admixture of compact quark-model state and hadronic molecular components. The decay width of $D_{s 0}^{*} (2317) \to D_{s}^{+} π^{0}$ is evaluated within the quark rearrangement framework. The transition $c s ˉ (1^{3} P_{0}) \to D_{s} π^{0}$ proceeds via the OZI-allowed $c s ˉ (1^{3} P_{0}) - D_{s} η$ coupling followed by $η - π^{0}$ mixing, which serves as the primary source of isospin violation in this channel. The coupling between $D K$ and $D_{s} π^{0}$ is computed in a quark rearrangement model, where the isospin violation effect originates from the mass difference between the $D^{0} K^{+}$ and $D^{+} K^{0}$ thresholds. The parameters of the scheme shares the same ones with those of the underlying potential model and only the vacuum production strength is adjusted to reproduce the physical $D_{s 0}^{*} (2317)$ mass. This calculation may shed more insight to the nature of exotic $D_{s 0}^{*} (2317)$ state and its isospin-breaking decay properties.
hep-ph1 citation
15
Unavoidable Loop-Induced Quintessence -- Higgs Mixing and Its Phenomenological Consequences
Zurab Kepuladze🇬🇪
We investigate a class of quintessence models in which the dark-energy scalar field interacts with sterile neutrinos responsible for neutrino mass generation through the seesaw mechanism. Radiative corrections involving sterile neutrinos induce Higgs-quintessence mixing and provide an effective portal between quintessence and Standard Model particles. We calculate the corresponding one-loop mixing amplitude and show that its structure depends on the relation between the characteristic momentum transfer and the sterile-neutrino mass. In the low-momentum regime the mixing is effectively kinetic, while at high energies it acquires a mass-mixing form. A notable result is that the overall suppression of the induced mixing is governed by the physical neutrino mass scale, leading to a predictive relation between neutrino properties and Higgs-quintessence interactions. The resulting loop-induced effects are found to be suppressed by factors comparable to those controlling the tree-level quintessence-neutrino interaction. The induced mixing generates effective couplings of quintessence to Standard Model fermions and gauge bosons, leading to modified Higgs, W and Z boson processes and opening decay channels for the quintessence field, which may prove to be cosmologically important. While the corresponding effects remain well below current experimental sensitivities in the minimal heavy-seesaw scenario, the framework establishes a direct connection between dark-energy dynamics, neutrino mass generation and Higgs-sector phenomenology and provides a basis for studying scenarios with lighter sterile neutrino states where observable effects may be enhanced.
hep-phastro-ph.CO0 citations
16
High-scale Mirror Standard Model Dark Matter, Dark Phase Transitions and Gravitational Waves Implications
V.K. Oikonomou🇬🇷
We consider a scenario for dark matter in the Universe, according to which the dark matter sector is comprised by a dark Standard Model sector which interacts only gravitationally with the ordinary Standard Model sector. This dark Standard Model sector is assumed to have the same symmetries as the ordinary Standard Model, with the couplings and the scale of the mirror Standard Model sector being different than the ordinary Standard Model sector. Specifically, the scale of the mirror Standard Model sector will be assumed to be quite higher compared to the ordinary Standard Model. Also the Yukawa couplings among the mirror Higgs and the mirror fermions are assumed to be different from those of the Standard Model and we examine the effects of the different scale and of the different Yukawas on the evolution of the Universe. As we show, a mirror world phase transition occurs at high temperatures of the baryonic Universe, which can be first order or second order, depending on the scale of the Universe and the Yukawa couplings. These are dark phase transitions which occur quite earlier than the real world Standard Model electroweak phase transition. The case of a second order phase transition is quite interesting phenomenologically, since it can potentially have a direct imprint on the spectrum of stochastic gravitational waves for frequencies probed by the future gravitational wave detectors. Also we examine whether this mirror dark matter world can form atoms and as we show in some scenario the high scale mirror dark matter can have both atomic and subatomic particle components. We also give an approximation of the total equation of state of high scale mirror DM and we discuss how high scale mirror DM can reconcile contradicting observations like the Bullet cluster and the Abell 520 cluster.
hep-phastro-ph.COgr-qchep-thEPJC(2026)·0 citations
17
Bose-enhanced Neutrino Decays in a Thermal Medium
Yuber F. Perez-Gonzalez🇪🇸 · Manibrata Sen🇮🇳 · Walter Tangarife🇺🇸
We compute the decay width of neutrinos in a thermal medium using finite-temperature quantum field theory, focusing on non-standard decays into lighter neutrinos and a scalar or light vector boson. We derive general expressions for the thermal decay rate and show that finite-temperature effects can dramatically enhance neutrino decays when the parent and daughter states are nearly degenerate in mass. In this regime, the emitted boson is kinematically soft and undergoes strong Bose enhancement, leading to decay widths that can exceed their vacuum values by a couple of orders of magnitude. We demonstrate that this effect is largely insensitive to the Lorentz structure of the underlying interaction and arises generically from the interplay of thermal occupation factors and quasi-degenerate kinematics. Our results highlight a previously underappreciated feature of neutrino decay in thermal environments and provide a general framework applicable to a broad class of fermionic decay processes.
hep-ph0 citations
18
Light hybrid baryons in the constituent model of QCD
Joachim Viseur · Claude Semay🇧🇪 · Cyrille Chevalier🇧🇪
Hybrid baryons, in which gluonic degrees of freedom play an explicit dynamical role, provide a key testing ground for nonperturbative quantum chromodynamics. In this work, we investigate the mass spectrum of light hybrid baryons composed of identical quarks within a phenomenological constituent framework, applied to a quark core-gluon approximation. In this approach, the hybrid baryon is described as a bound state of a color-octet three-quark core and a constituent gluon, allowing the original four-body problem to be reduced to a three-body calculation followed by an effective two-body treatment. The spectrum of the color-octet quark core is obtained by solving a semirelativistic three-quark Hamiltonian with linear confinement, Coulomb, and regularized hyperfine interactions using an oscillator basis expansion. Finite-size effects of the core are incorporated through the convolution of the effective core-gluon interaction with the spatial quark density. The resulting two-body problem, whose associated Hamiltonian has the same shape as the one of the core, is solved applying the helicity formalism and using the Lagrange mesh method. Our results predict the lightest hybrid baryons to occur at energies above $3 GeV$ , with negative-parity states generally lying below their positive-parity counterparts. The predicted spectra are compared with lattice QCD and QCD sum-rule calculations, showing qualitative agreement although the lowest-lying lattice QCD results are significantly lighter than the present ones. Possible extensions of the model and implications for future experimental searches are discussed.
hep-ph1 citation
19
Tripartite entanglement of oscillating and decohering neutrinos
Subhashish Banerjee🇮🇳 · Heinrich Päs🇩🇪 · Erika Rani🇩🇪
We study entanglement measures for oscillating neutrinos in the wave-packet formalism and confirm that an oscillating neutrino exhibits genuine tripartite entanglement and can be characterized as a member of the W class of states. We also show that this feature survives in the decoherence limit, and discuss the effect of CP phases on the entanglement. These findings provide new insights into the quantum nature of neutrino oscillations and their potential role in quantum information science, especially for neutrinos propagating large distances such as the astrophysical neutrinos observed at neutrino telescopes.
hep-ph1 citation
20
Cosmological signals of dark matter semi-annihilation
Boris Betancourt Kamenetskaia🇰🇷 · Mathias Garny🇩🇪 · Alejandro Ibarra🇩🇪 · Alessia Musumeci🇩🇪 · Merlin Reichard🇰🇷
The growth of primordial density fluctuations in the early Universe leads to an inhomogeneous dark matter distribution at high redshift, where semi-annihilation processes of the form $χχ \to χ^{c} ϕ$ , with $ϕ$ being dark radiation, can occur with a sizable rate. Using a state-of-the-art model for the cosmological boost factor, we compute the resulting redshift-dependent flux of boosted dark matter particles generated by semi-annihilation, and we study the implications of the boosted component for structure formation and direct detection experiments. We find a model independent upper limit on the semi-annihilation cross-section from structure formation, which reads $⟨ σ_{2 \to 1} v ⟩ \leq 4.2 \times 1 0^{- 19} (m_{χ} /1 GeV) cm^{3} / s$ . Further, we find that the cosmological contribution to the boosted dark matter flux can be comparable to the galactic one, providing an $O (1)$ enhancement to the sensitivity of dark matter searches, thus slightly enhancing the discovery potential in direct detection experiments of semi-annihilation scenarios where the dark matter interacts with the nucleus.
hep-ph1 citation
21
Efficient calculation of exclusive diffractive cross sections at the EIC and LHeC with the Sartre event generator
Tobias Toll🇮🇳 · Dipan Ghosh🇮🇳 · Abhinav Srivastav🇮🇳
We present a new version of the Sartre event generator for exclusive diffraction at small xP in the colour dipole model, for $e p$ and $e$ A scattering at the EIC and the LHeC as well as ultra-peripheral $pp$ , $p$ A, and AA collisions at RHIC and the LHC. Sartre stores the first and second moment of the interaction amplitudes in lookup tables which are then used for efficient event generation. There are many possible combinations of processes in Sartre, with different initial state nuclear targets and different final state vector mesons or real photons. We also want to implement different versions of the dipole model: with and without non-linear saturation effects, with and without nucleon hotspot substructure. A long-standing bottleneck for simulating all possible exclusive processes has been the production of lookup tables, which take a few CPU-year for each combination, necessitating the use of computing farms. The calculation also involves integrations of rapidly fluctuating integrands, which may cause numerical glitches which takes much effort to smoothen out. In this paper we present a solution to these issues, by presenting a new numerical calculation which improves the efficiency in the table production by 3-4 orders of magnitudes. This enables us to produce lookup tables for any process that we may be interested in, in a few hours. The new calculation does also not exhibit numerical glitches. We provide novel predictions for the EIC and the LHeC using the new version of Sartre.
hep-ph0 citations
22
The unintuitive SU(3) flavor and chiral limits of hadron resonances
José Ramón Peláez🇪🇸 · Pablo Rabán🇪🇸 · Jacobo Ruiz de Elvira🇪🇸
Contrary to naive expectations, poles used to define hadron resonances rigorously in the physical world may not evolve continuously to become degenerate in the SU(3) $_{F}$ and chiral limits of QCD. Instead, other shadow poles, usually ignored, may be the ones that degenerate and characterize the resonances in these limits. This feature is general, and we illustrate it first with the simple and familiar light-vector mesons, followed by the much-discussed light-scalar case. Their shadow poles and their degeneracy are found using the QCD low-energy effective theory unitarized to one loop.
hep-phhep-exhep-latnucl-th3 citations
23
In search for signals of the $D D ˉ$ bound state $X (3700)$ from study of the $B^{+} \to D^{+} D^{-} K^{+}$ , $B^{0} \to D^{+} D^{-} K^{0}$ and $Λ_{b} \to D^{+} D^{-} Λ$ reactions
Xiu-Lei Ren🇨🇳 · Hai-Peng Li🇨🇳 · Wei-Hong Liang🇨🇳 · Chu-Wen Xiao🇨🇳 · Eulogio Oset🇪🇸
We perform a theoretical study of the $B^{+} \to D^{+} D^{-} K^{+}$ , $B^{0} \to D^{+} D^{-} K^{0}$ and $Λ_{b} \to D^{+} D^{-} Λ$ reactions by looking at the production mechanisms, with special emphasis in the final state interaction of the charmed mesons, which gives rise to the $X (3930)$ , coupling strongly to $D_{s} D ˉ_{s}$ , and another state that we call $X (3700)$ , coupling strongly to $D D ˉ$ that qualifies as a $D D ˉ$ bound state. The combined study of all these reactions shows that the final state interaction responsible for the production of these resonances is more important in the $B^{+} \to D^{+} D^{-} K^{+}$ reaction than in the $Λ_{b} \to D^{+} D^{-} Λ$ one. We have taken this into account and shown that normalizing the $D^{+} D^{-}$ mass distributions to the same value at the peak of the $ψ (3770)$ production, the two mass distributions are quite different in a range of 10 MeV above the $D^{+} D^{-}$ threshold, with a value about an order of magnitude bigger for the $B^{+} \to D^{+} D^{-} K^{+}$ reaction than for the $Λ_{b} \to D^{+} D^{-} Λ$ one. The $D^{+} D^{-}$ mass distribution by itself also shows an enhancement of about one order of magnitude in the presence of the $X (3700)$ with respect to a calculation where this resonance is absent. We make a call to measure these magnitudes in the coming LHCb upgrades, which would bring great support to the existence of the bound $D^{+} D^{-}$ state.
hep-ph1 citation
24
Leptonic flavour transfer: a new window on flavour gauge symmetries
L. Darmé🇫🇷 · N. Fardeau🇫🇷 · F. Mahmoudi🇫🇷 · M. Palmiotto🇳🇴
New flavour non-abelian gauge groups, which may arise as part of a fundamental theory of flavour, can lead to distinctive flavour-transfer processes. When restricted to the lepton sector, such processes partially mimic the standard charged current interactions at low energy. We explicitly study such constructions with various flavour structures, and investigate systematically all relevant accelerator-based constraints, exploring specific experimental signatures for these models. In the absence of flavour-breaking spurions, constraints from heavy lepton lifetime are found to dominate over most of the parameter space, with specific parts still open for future ee-collider searches. Numerical predictions are obtained using the \texttt{MARTY} framework, allowing us to consistently explore both the light- and heavy-mediator regimes. Finally, using \darkpack, we also assessed that extensions of such models could be compatible with dark matter relic density bounds.
hep-ph0 citations
25
On the survival of dark matter spikes: Stellar and compact-object perturbations
Theophanes K. Karydas🇳🇱 · Francesca Scarcella🇪🇸 · Bradley J. Kavanagh🇪🇸 · Gianfranco Bertone🇳🇱
Establishing realistic expectations for the dark matter (DM) distribution near a supermassive black hole (BH) is essential for assessing environmental imprints on gravitational wave (GW) signals. Using the Galactic Center as an observationally constrained case study, we investigate the evolution of DM density spikes under gravitational perturbations from the nuclear stellar and black hole populations surrounding the central BH. We find that scattering of DM particles by the nuclear star cluster depletes the DM distribution at radii $r \sim 1 0^{- 1} pc$ , far outside the region where the relevant GW signals are produced. At smaller radii, at $r \sim 1 0^{- 3} pc$ , the closest known stellar perturbers, S2 and S38, induce only negligible changes to the density profile. At still smaller radii, where no stellar perturbers are currently known, we assess the cumulative impact of past EMRIs by modelling successive mergers with stellar-mass BHs of mass $\sim 10 M_{⊙}$ , in numbers consistent with the expected rate over $10 Gyr$ . We find that these events do not erase the central overdensity, reducing the density only to approximately $82%$ of its initial value at $r ≲ 1 0^{- 5} pc$ . Our results indicate that, at least at the Galactic Center, DM overdensities around the central BH are expected to remain largely intact under stellar perturbations and plausible stellar-BH merger histories.
↳ astro-ph.GAastro-ph.HEgr-qchep-ph2 citations
26
Resurgence of the Thermal Transition between Bounce and Sphaleron
Shaun D. Hampton🇰🇷 · Kyungsun Lee🇰🇷 · Sungjay Lee🇰🇷
We study the thermal transition between the bounce and the sphaleron in quantum mechanics with a metastable vacuum from the viewpoint of Borel resurgence. For two models representing a second-order and a first-order transition, we compute the perturbative expansion of the thermal free energy to high orders and extract the leading Borel singularity data $(A, b, S)$ as functions of temperature. The Borel singularity location $A$ reproduces the on-shell action of the dominant saddle on both sides of the transition, joining smoothly in the second-order case and developing a kink in the first-order case. The characteristic exponent $b$ jumps between $0$ and $1/2$ across the transition, counting the zero modes of the corresponding saddle. The Stokes constant $S$ matches the one-loop determinant around the saddle. The perturbative expansion around the false vacuum thus determines the transition temperature, the order of the transition, and the decay rate including the one-loop prefactor without relying on semiclassical inputs.
↳ hep-thcond-mat.stat-mechhep-phquant-ph1 citation
27
Hadron spectra of finite-density QC $_{2}$ D
Kei Iida🇯🇵 · Etsuko Itou🇯🇵 · Kotaro Murakami🇯🇵 · Daiki Suenaga🇯🇵
We investigate the chemical-potential dependence of hadron spectra in two-color QCD using first-principles lattice simulations. We compute two-point correlation functions for all allowed hadronic operators by newly including the contributions from disconnected diagrams, and extract the corresponding effective masses. In the meson sector, the mass hierarchy in the hadronic phase (normal vacuum) is found to be $m_{π} ≲ m_{η} < m_{σ} (noisy) < m_{ρ} \sim m_{ω} ≪ m_{a_{1}}$ , which is similar to that in three-color QCD. In the superfluid phase, this hierarchy is modified, and with increasing density it changes to $m_{σ} (noisy) < m_{a_{1}} < m_{ρ} < m_{π} \sim m_{η} (noisy) ≪ m_{ω} (noisy)$ . In the diquark sector, the ordering remains as $m_{N G} ≲ m_{I = 0, S} < m_{I = 1, A V} < m_{I = 0, P S} ≲ m_{I = 0, V}$ in both phases, and the Nambu--Goldstone mode associated with spontaneous breaking of $U (1)_{B}$ is confirmed to be nearly massless. Furthermore, by comparing correlators for chiral partners, we find indications of chiral symmetry restoration at high density.
↳ hep-lathep-phnucl-exnucl-th4 citations
28
Constraints on Stable Scalar-Tensor Dark Energy from DESI Data and Solar System Tests
Husam Adam🇺🇸 · Mark P. Hertzberg🇺🇸 · Daniel Jiménez-Aguilar🇺🇸
We investigate the viability of scalar-tensor (quintessence) models of dark energy with a quartic polynomial nonminimal coupling to gravity and a linear scalar potential. The polynomial nonminimal coupling is used to ensure that the field is well stabilized in the early universe. We perform a systematic exploration of the parameter space spanned by the quadratic and quartic nonminimal couplings, as well as the slope of the potential. We confront the predictions of the model with the latest Dark Energy Spectroscopic Instrument (DESI) constraints on the dark energy equation of state and also with complementary bounds from local tests of gravity, including solar system constraints and limits on the time variation of the effective Newton's constant. We identify bands in parameter space where all these constraints are satisfied, finding such bands to be very narrow.
↳ astro-ph.COgr-qchep-phhep-th1 citation
29
Energy and centrality dependence of thermodynamical observables from multiplicity in Pb+Pb and Au+Au collisions
Francisco Reyes Rodríguez🇲🇽 · Eleazar Cuautle🇲🇽
Using a statistical model, we analyze published multiplicity distributions for identified hadrons produced in heavy ion collisions in the energy range from 2.7-200 \gev. Our analysis enables the prediction of the multiplicity distributions for multi-strangeness hadrons that have not yet been measured in lower-energy experiments. Furthermore, we obtain freeze-out parameters, including temperature, baryon chemical and strangeness potentials, the strangeness suppression factor, and the system radius, as functions of centrality and collision energy. Additionally, we computed and discussed the Skewness and its behavior at lower collision energies, highlighting the importance of the freeze-out parameters in determining the liquid-gas phase transition in nuclear matter.
↳ nucl-thhep-phEPJA(2026)·0 citations
30
Determining Neutrino Mass Ordering with NOvA and Upcoming JUNO Measurements
NOvA Collaboration
NOvA has reported a significance of mass ordering determination using ten years of data together with external constraints from reactor-based experiments. The JUNO collaboration is poised to provide a more precise reactor-based constraint on $∣Δ m_{32}^{2} ∣$ . In this Letter, we explore the potential impact of this anticipated measurement on the determination of the neutrino mass ordering by NOvA. We find that $3 σ$ evidence of the normal ordering is achievable over a range of plausible JUNO measurements within the next five years.
↳ hep-exhep-ph1 citation
31
A Novel Approach to Short Baseline Oscillation Searches Using Neutrino Tagging with nuSCOPE
Adrien Blanchet🇫🇷 · César Jesús-Valls🇨🇭 · Animesh Chatterjee🇨🇭 · Stephen Dolan🇨🇭 · Pierre Granger🇨🇭 · Laura Munteanu🇨🇭
We present the first study of short-baseline neutrino oscillation searches using a tagged neutrino beamline, taking the proposed nuSCOPE facility at CERN as a benchmark. In this Letter we demonstrate that tagged neutrino beams, where the neutrino flavor, energy, and propagation distance are determined with exceptional event-by-event precision, provide a new experimental approach to search for non-standard neutrino oscillations. We evaluate the sensitivity to sterile-neutrino-induced oscillations in the $ν_{μ}$ disappearance, $ν_{μ} \to ν_{e}$ appearance, and $ν_{e}$ disappearance channels, demonstrating the ability to probe multiple flavor transitions and both appearance and disappearance modes within a single experiment. Our results show that tagged beams enable sensitivity improvements to mass-squared splittings spanning several orders of magnitude while substantially reducing the dependence on neutrino flux predictions that limits conventional searches. We find that nuSCOPE can probe a broad region of parameter space motivated by existing anomalies and extend coverage into previously unexplored territory, demonstrating the strong potential of tagged neutrino beams for precision oscillation physics.
↳ hep-exhep-ph1 citation
32
Finite-volume effects on smeared spectral densities
Francesca A. Bresciani🇮🇹 · Mattia Bruno🇮🇹 · Maxwell T. Hansen🇬🇧
Using two distinct approaches, we derive a universal expression for the leading finite-volume effects of the smeared vector-vector spectral density (proportional to the smeared hadronic $R$ -ratio) in a periodic cubic spatial volume of side length $L$ . First, building on the results of previous work for finite-volume effects on Euclidean two-point functions, we show that the $L$ dependence is exponentially suppressed for a certain class of smearing kernels, and that the leading effects can be expressed universally in terms of the pion form factor. The same representation is then derived starting from the Lellouch-Lüscher-Meyer expression for the spectral decomposition of the correlator. The results may prove useful for controlling the $L \to \infty$ extrapolation of smeared spectral densities, in particular by defining a scaling regime in which the finite-volume effects are dominated by the leading terms in a large $L$ expansion and thus can be reliably estimated. To illustrate this point, we also present numerical estimates based on various kernels and models of particle interactions. Despite focusing on the vector channel, our derivation defines a general framework applicable to other cases as well.
↳ hep-lathep-phhep-th5 citations
33
Machine-learned particle flow as a foundation model for collider physics
Farouk Mokhtar🇺🇸 · Joosep Pata🇪🇪 · Michael Kagan🇺🇸 · Javier Duarte🇺🇸
The workflow from particle collision to physics analysis passes through a series of reconstruction steps that are traditionally modular and disconnected, with no shared representation linking low-level detector data to high-level analysis tasks. We show that casting event reconstruction as a machine learning problem naturally produces such a shared representation. We repurpose a machine learning model trained for particle-flow reconstruction (MLPF) to perform three distinct analysis tasks: jet flavor identification, jet energy regression, and missing momentum regression. By appending the per-particle latent representations learned during reconstruction as additional input features, we substantially improve over baselines that use kinematic features alone. We further demonstrate that a single linear layer trained using only the latent representations achieves competitive performance against state-of-the-art baseline architectures, and outperforms the baseline for missing momentum regression with approximately 35 times fewer parameters. These results demonstrate that the latent representations learned during reconstruction encode essential physics information needed for downstream analysis, establishing MLPF as a foundation model and offering a concrete step toward an end-to-end pipeline from detector data to physics analysis.
↳ hep-excs.LGhep-phphysics.data-an+11 citation
34
Resonant scattering in two-flavored Sp(4) lattice gauge theories
Ed Bennett🇬🇧 · Yannick Dengler🇦🇹 · Deog Ki Hong🇰🇷 · Ho Hsiao🇯🇵 · Jong-Wan Lee🇰🇷 · C.-J. David Lin🇹🇼 · Biagio Lucini🇬🇧 · Axel Maas🇦🇹 · Maurizio Piai🇬🇧 · Davide Vadacchino🇬🇧 · Fabian Zierler🇬🇧
We apply Lüscher's method to the vector channel of the scattering amplitude of Pseudo-Nambu-Goldstone-Bosons (PNGBs), in the $S p (4)$ lattice gauge theory coupled to $N_{f} = 2$ flavors of Wilson-Dirac fundamental fermions. We generalize existing algorithms and numerical implementations of the method, to adapt them to this prominent candidate for the completion of proposed extensions of the Standard Model (SM). We present the first ab initio measurements of key properties of the vector resonances in the theory, including the coupling to the PNGBs, that are relevant to direct and indirect new physics searches, both for composite Higgs models (CHMs), as well as for strongly interacting massive particle (SIMP) realizations of dark matter. We also present a global update of the spectroscopy of the mesons in the theory, improving both the statistics and analysis systematics in respect to previous lattice measurements reported in the literature.
↳ hep-lathep-ph0 citations
35
A Supernova Constraint on F-theory
Sebastian Vander Ploeg Fallon🇺🇸 · James Halverson🇺🇸 · Liam McAllister🇺🇸 · David J. E. Marsh🇬🇧
We study constraints on the quantum chromodynamics (QCD) axion in F-theory, a strongly coupled limit of string theory. We build models of QCD from compactifications to four dimensions on elliptic fibrations over toric threefolds $B_{3}$ , characterized by an integer $N = h^{1, 1} (B_{3})$ . The QCD axion mass increases with $N$ , and we find that models with sufficiently high $N$ are inconsistent with observations of the neutrino burst from supernova 1987A, disfavoring large regions of the moduli space. Specifically, at least $95%$ of models with $N \geq 8, 791$ -- a regime that arguably contains the vast majority of known F-theory topologies -- have a QCD axion mass $m_{QC D} > 15 m e V$ and are thus constrained. This limit is independent of cosmology. We only consider weakly-curved threefolds, where $α^{'}$ corrections are plausibly negligible.
↳ hep-thastro-ph.COhep-ph0 citations
36
Primal Bootstrap for Pion Scattering at Large-N
Sebastiano Bocchia🇬🇧 · Alessandro Vichi🇮🇹
We introduce a basis for tree-level meromorphic scattering amplitudes suitable for describing pion scattering in the large-N limit. The basis is constructed as linear combinations of Lovelace-Shapiro-like amplitudes with varying Regge slopes and intercepts. The resulting amplitudes satisfy by construction the fundamental requirements of analyticity, crossing symmetry, and Regge behavior. We analyze their behavior in specific kinematical regimes, including the high-energy fixed-angle limit. We also show that finite linear combinations of our basis elements need not violate unitarity. Nonetheless, because unitarity is not imposed by construction, we enforce it a posteriori by requiring positivity of the partial-wave decomposition. This condition can be formulated as an optimization problem and solved numerically. The solutions to this primal bootstrap problem yield meromorphic amplitudes that satisfy all the aforementioned constraints. We compare several observables with the bounds obtained from the dual positivity conditions and show that our family of amplitudes spans the full allowed parameter space. With appropriate modifications, this method can be extended to construct amplitude families for broader applications.
↳ hep-thhep-lathep-ph2 citations

Affiliations

first authorsco-authorsvia INSPIRE