HEP Phenomenology·hep-ph

Wed·Oct 30, 2024Wednesday·October 30, 2024

52 papers—37 primary·15 cross-listed·reconstructed*

01*
Majorana CP Violation Insights from Decaying Neutrinos
Sabila Parveen🇮🇳 · Soumya Bonthu🇺🇸 · Newton Nath🇪🇸 · Ujjal Kumar Dey🇮🇳 · Poonam Mehta🇮🇳
It is well-known that within the standard three flavor neutrino oscillation formalism, the Majorana phases appearing in the neutrino mixing matrix cannot have any effect on neutrino oscillation probabilities thereby evading testability at neutrino oscillation experiments. We consider an effective non-Hermitian Hamiltonian describing three flavor neutrino oscillations with the possibility of neutrino decay and demonstrate that the two Majorana phases can entangle with the off-diagonal decay terms and appear at the level of oscillation probabilities. Using the Cayley-Hamilton theorem, we derive approximate analytical expressions for three flavor neutrino oscillation probabilities in the presence of neutrino decay, taking into account matter effects. In the context of a long baseline neutrino experiment, we then analyse the impact of Majorana phases on the oscillation probabilities for different channels as well as on observables related to CP violation effects in neutrino oscillations. Finally, we discuss the effect of Majorana phases on the parameter degeneracies in the neutrino oscillation framework.
hep-phNPB(2026)·1 citation
02*
Determination of the strong coupling constant and the Collins-Soper kernel from the energy-energy correlator in $e^{+} e^{-}$ collisions
Zhong-Bo Kang🇺🇸 · Jani Penttala🇺🇸 · Congyue Zhang🇺🇸
We have conducted the first simultaneous global fit of the strong coupling constant $α_{s}$ and the Collins-Soper (CS) kernel using the energy-energy correlators (EEC) of $e^{+} e^{-}$ collisions in the back-to-back limit. This analysis, based on the transverse-momentum-dependent (TMD) factorization of EEC at next-to-next-to-next-to-leading logarithmic ( $N^{3} LL$ ) accuracy, yields $α_{s}$ consistent with the world average. We have tested two different parametrizations for the non-perturbative CS kernel and found both to align with results obtained from lattice QCD and fits on semi-inclusive deep inelastic scattering and Drell-Yan process.
hep-phhep-exnucl-exnucl-th37 citations
03*
Probing third-generation New Physics with $K \to π ν ν ˉ$ and $B \to K^{(*)} ν ν ˉ$
Lukas Allwicher🇨🇭 · Marzia Bordone🇨🇭 · Gino Isidori🇨🇭 · Gioacchino Piazza🇨🇭 · Alfredo Stanzione🇮🇹
The recent observation of the $K^{+} \to π^{+} ν ν ˉ$ decay by NA62 is an important milestone in precision flavor physics. Together with evidence of $B^{+} \to K^{+} ν ν ˉ$ reported by Belle-II, they are the only FCNC decays involving third-family leptons where a precision close to the SM expectation has been reached. We study the implications of these recent results in the context of a new physics scenario aligned to the third generation, with an approximate $U (2)^{5}$ flavor symmetry acting on the light families. We find that the slight excess observed in both channels supports the hypothesis of non-standard TeV dynamics of this type, as also hinted at by other $B$ -meson decays, consistently with bounds from colliders and electroweak observables. We further discuss how future improvements in precision could affect this picture, highlighting the discovery potential in these di-neutrino modes.
hep-phPLB(2025)·46 citations
04*
On the Interplay of Nuclear and Higher-Twist Corrections in Nuclear Structure Functions
S.I. Alekhin🇩🇪 · S.A. Kulagin🇷🇺 · R. Petti🇺🇸
We discuss results from our global QCD analyses including nuclear data off deuterium from various measurements, as well as off $\htri$ and $\hetri$ targets from the \mara{} experiment. We simultaneously determine the parton distribution functions of the proton, the higher-twist terms, and the nucleon off-shell correction functions responsible for the modifications of the partonic structure in bound protons and neutrons. In particular, we study the neutron-proton asymmetry of the off-shell correction and its interplay with the treatment of the higher-twist terms. We observe that the data on the $\hetri / \htri, \hetri / \hdeu$ , and $\htri / \hdeu$ cross section ratio are in good agreement with the predictions based on a single isoscalar off-shell function. We provide the corresponding predictions on the ratio $F_{2}^{n} / F_{2}^{p}$ , on the $d$ and $u$ quark distributions in the proton and in the $\htri$ and $\hetri$ nuclei, as well as for future measurements of the EMC effect with parity-violating Deep Inelastic Scattering (DIS).
hep-phPoS(2025)·2 citations
05*
Gravitational Waves from Phase Transitions
Djuna Croon🇬🇧 · David J. Weir🇫🇮
We summarise the physics of first-order phase transitions in the early universe, and the possible ways in which they might come about. We then focus on gravitational waves, emphasising general qualitative features of stochastic backgrounds produced by early universe phase transitions and the cosmology of their present-day appearance. Finally, we conclude by discussing some of the ways in which a stochastic background might be detected.
hep-phastro-ph.COContemp.Phys.(2024)·24 citations
06*
Energy-Enhanced Dimension Eight SMEFT Effects in VBF Higgs production
Benoît Assi🇺🇸 · Adam Martin🇺🇸
We study Higgs boson production via vector boson fusion at the LHC, focusing on the process $pp \to H + j j$ and capturing the leading energy-enhanced contributions within the Standard Model Effective Field Theory (SMEFT) up to order $1/ Λ^{4}$ . Employing energy-scaling arguments, we predict the magnitude of each higher-dimensional operator's contribution. Utilizing the geometric formulation of SMEFT, our analysis incorporates dimension-eight operators not previously considered. We find that the kinematics of vector boson fusion - characterized by two highly forward jets - tend to suppress contributions from higher-dimensional operators, requiring a lower scale $Λ$ for SMEFT effects to become observable. This suggests that the SMEFT remains valid for lower $Λ$ than expected. Combined with the fact that LEP constrains the dimension-six operators with the most considerable impact on vector boson fusion, a regime exists where dimension-eight operators can have significant effects. In many cases, these dimension-eight operators also influence associated production processes like $pp \to H V (j j)$ , though differences in analysis cuts and kinematics mean this is not always the case. Our findings provide insights that could refine the search for SMEFT signals in collider experiments.
hep-phJHEP(2025)·9 citations
07*
Pi in the Sky: Neutron Stars with Exceptionally Light QCD Axions
Mia Kumamoto🇺🇸 · Junwu Huang🇨🇦 · Christian Drischler🇺🇸 · Masha Baryakhtar🇺🇸 · Sanjay Reddy🇺🇸
We present a comprehensive study of axion condensed neutron stars that arise in models of an exceptionally light axion that couples to quantum chromodynamics (QCD). These axions solve the strong-charge-parity (CP) problem, but have a mass-squared lighter than that due to QCD by a factor of $ε < 1$ . Inside dense matter, the axion potential is altered, and much of the matter in neutron stars resides in the axion condensed phase where the strong-CP parameter $θ = π$ and CP remains a good symmetry. In these regions, masses and interactions of nuclei are modified, in turn changing the equation of state (EOS), structure and phenomenology of the neutron stars. We take first steps toward the study of the EOS of neutron star matter at $θ = π$ within chiral effective field theory and use relativistic mean field theory to deduce the resulting changes to nuclear matter and the neutron star low-density EOS. We derive constraints on the exceptionally light axion parameter space based on observations of the thermal relaxation of accreting neutron stars, isolated neutron star cooling, and pulsar glitches, excluding the region up to $5 \times 1 0^{- 7} ≲ ε ≲ 0.2$ for $m_{a} ≳ 2 \times 1 0^{- 9} eV$ . We comment on potential changes to the neutron star mass-radius relationship, and discuss the possibility of novel, nuclear-density compact objects with $θ = π$ that are stabilized not by gravity but by the axion potential.
hep-phastro-ph.HEnucl-thPRD(2025)·34 citations
08*
Transverse Orbital Angular Momentum in the Proton
Osamah Alkasassbeh🇯🇴 · Abha Rajan🇺🇸 · Michael Engelhardt🇺🇸 · Simonetta Liuti🇺🇸
Using the equations of motion of QCD and Lorentz invariance relations, we show a new, more direct way of obtaining the decomposition of the proton's quark transverse angular momentum into its spin and orbital components. The new decomposition can be understood as a twist-three relation, with the quark transverse spin described by the parton distribution $g_{T}$ . We find that the orbital component can be expressed in terms of a moment in the quark transverse momentum, $k_{T}$ , of the generalized transverse momentum-dependent distribution $F_{12}$ , or alternatively in terms of the twist-three generalized parton distributions $H_{2 T}$ and $E_{2 T}$ .
hep-phnucl-thPLB(2026)·1 citation
09*
Phenomenological exploration of the strong coupling constant in the perturbative and nonperturbative regions
M. De Sanctis🇨🇴
The QCD running coupling costant is studied in the perturbative region, considering the existing experimental data, and also in the nonperurbative region, at low momentum transfer. A continous phenomenological function is determined by means of three different models also calculating the corresponding finite value of the vector quark self-energy. These two quantities are used for the vector interaction of a Dirac relativistic model for the charmonium spectrum. The process required to fit the spectrum is discussed and the relationship with previous models is analyzed.
hep-phActa Phys.Polon.B(2024)·3 citations
10*
Is the finite temperature effective potential, effective for dynamics?
Nathan Herring🇺🇸 · Shuyang Cao🇺🇸 · Daniel Boyanovsky🇺🇸
We study the applicability of the finite temperature effective potential in the equation of motion of a homogeneous "misaligned" scalar condensate $φ$ , and find important caveats that severely restrict its domain of validity: i:) the assumption of local thermodynamic equilibrium (LTE) is in general not warranted, ii:) we show a direct relation between the effective potential and the thermodynamic entropy density $S = - \partial V_{e f f} (T, φ) / \partial T$ , which entails that for a dynamical $φ (t)$ the entropy becomes a non-monotonic function of time, iii:) parametric instabilities in both cases with and without spontaneous symmetry breaking lead to profuse particle production with non-thermal distribution functions, iv:) in the case of spontaneous symmetry breaking spinodal instabilities yield a complex effective potential, internal energy and entropy, an untenable situation in thermodynamics. All these caveats associated with dynamical aspects, cannot be overcome by finite temperature equilibrium resummation schemes. We argue that the dynamics of the condensate leads to decoupling and freeze-out from (LTE), and propose a closed quantum system approach based on unitary time evolution. It yields the correct equations of motion without the caveats of the effective potential, and provides a fully renormalized and thermodynamically consistent framework to study the dynamics of the "misaligned" condensate, with real and conserved energy and entropy amenable to numerical study. The evolution of the condensate leads to profuse stimulated particle production with non-thermal distribution functions. Possible emergent asymptotic non-thermal states and eventual re-thermalization are conjectured.
hep-phhep-thPRD(2025)·7 citations
11*
Detection of Dark Matter using levitated nanoparticles within a Bessel-Gaussian beam via Yukawa coupling
Iftekher S. Chowdhury🇦🇺 · Binay Prakash Akhouri🇮🇳 · Shah Haque🇦🇺 · Martin H. Bacci🇦🇺 · Eric Howard🇦🇺
We present a novel experimental approach to detect dark matter by probing Yukawa interactions, commonly referred to as a fifth force, between dark matter and baryonic matter. Our method involves optically levitating nanoparticles within a Bessel-Gaussian beam to detect minute forces exerted by potential dark matter interaction with test masses. The non-diffracting properties of Bessel-Gaussian beams, combined with feedback cooling techniques, provide exceptional sensitivity to small perturbations in the motion of the nanoparticles. This setup allows for precise control over trapping conditions and enhances the detection sensitivity to forces on the order of $10^{-18}$ N. We explore the parameter space of the Yukawa interaction, focusing on the coupling strength ($\alpha$) and interaction range ($\lambda$), and discuss the potential of this experiment to place new constraints on dark matter couplings, complementing existing direct detection methods.
hep-phgr-qchep-exSensors(2025)·0 citations
12*
Scalar dark matter multiplet of global $O (N)$ symmetry
U-Rae Kim🇰🇷 · Jungil Lee🇰🇷 · Soo-hyeon Nam🇰🇷
We study two types of models involving a scalar dark matter multiplet of global $O (N)$ symmetry. These models are distinguished by the absence (Type I) or presence (Type II) of a scalar mediator with $Z_{2}$ symmetry. We derive the allowed regions for the dark matter mass and new scalar couplings based on constraints from Higgs invisible decay, the relic abundance of dark matter, and the spin-independent dark matter-nucleon scattering cross section. Within the allowed parameter space, we also discuss the vacuum stability of the Higgs potential and the perturbativity of the scalar couplings in both models. We find that the Type I model cannot achieve stable electroweak vacuum, whereas the Type II model can have both a stable vacuum and perturbative couplings up to the Planck scale.
hep-phhep-exJHEP(2025)·1 citation
13*
Weak semileptonic decays of vector mesons in the NJL model
M. K. Volkov🇷🇺 · A. A. Pivovarov🇷🇺 · K. Nurlan🇷🇺
The decay widths of $V \to K (π) l ν ˉ_{l}$ are calculated within the Nambu--Jona-Lasinio model, where $V = K^{*}, ρ, ω, ϕ$ and $l = μ, e$ . The results are obtained using the previously fixed model parameters without introducing any arbitrary parameters. The obtained results are considered as predictions due to the absence of experimental data.
hep-phInt.J.Theor.Phys.(2025)·1 citation
14*
Probing the mass effect of heavy quark jets in high-energy nuclear collisions
Sa Wang🇨🇳 · Shuang Li🇨🇳 · Yao Li🇨🇳 · Ben-Wei Zhang🇨🇳 · Enke Wang🇨🇳
The production of heavy quark (HQ) jets provides a new arena to address the mass effect of jet quenching in heavy-ion physics. This paper presents a theoretical study of HQ jet yield suppression in Pb+Pb collisions at the LHC and focuses on the energy loss of HQ jets produced by different mechanisms. The p+p baseline is carried out by the SHERPA generator, and the jet-medium interactions are described by the SHELL transport model, which considers the elastic and inelastic partonic energy loss in the quark-gluon plasma (QGP). In p+p collisions, our numerical results indicate that the HQ jets from gluon splitting ( $g \to Q$ -jet) give the dominant contribution at high $p_{T}$ , and it shows more dispersive structures than the HQ-initiated one ( $Q \to Q$ -jet). In nucleus-nucleus collisions, our calculations are consistent with the inclusive and b-jet $R_{AA}$ recently measured by the ATLAS collaboration, which suggests a remarkable manifestation of the mass effect of jet energy loss. As a result of the dispersive substructure, the $g \to Q$ -jet will lose more energy than the $Q \to Q$ -jet in the QGP. Due to the significant contribution of $g \to c$ -jet, the $R_{AA}$ of c-jet will be comparable or even smaller than that of inclusive jet. To experimentally distinguish the $g \to Q$ -jet and $Q \to Q$ -jet, we propose the event selection strategies based on their topological features and test the performances. By isolating the $c \to c$ -jet and $b \to b$ -jet, the jets initiated by heavy quarks, we predict that the order of their $R_{AA}$ are in line with the mass hierarchy of energy loss. Future measurements on the $R_{AA}$ of $Q \to Q$ -jet and $g \to Q$ -jet will provide a unique chance to test the flavor/mass dependence of energy loss at the jet level.
hep-phnucl-thCPC(2025)·5 citations
15*
A more novel approach of radiative linear seesaw in a modular $A_{4}$ symmetry
Takaaki Nomura🇨🇳 · Hiroshi Okada🇨🇳
We propose a radiatively induced linear seesaw model that is perfectly realized at leading order by a modular $A_{4}$ symmetry. Because this group also has a flavor symmetry, we obtain some predictions concentrating on two specific regions at nearby fixed points $τ = ω$ and $i$ . Through our numerical chi square analysis, we show predictions for each the case depending on the neutrino mass ordering; normal and inverted one.
hep-phPTEP(2025)·11 citations
16*
Quantum coherence between mass eigenstates of a neutrino can be destroyed by its mass-momentum entanglement
Shi-Biao Zheng🇨🇳
If a neutrino or antineutrino produced in the decay of an unstable particle is not entangled to its accompanying particles, its mass is necessarily correlated with its momentum. In this manuscript, I illustrate that this entanglement would destroy the quantum coherence between the neutrino's mass eigenstates in both the momentum and position representations, which was overlooked by other authors in previous investigations of entanglement and coherence associated with neutrino oscillations. I further point out that the states of a neutrino and an electron become nonseparable after their charged-current interaction. This nonseparability leads to decoherence for neutrinos propagating in matter, but was not taken into consideration in previous investigations of the matter effect.
hep-phquant-ph3 citations
17*
Invisible Higgs decay from dark matter freeze-in at stronger coupling
Oleg Lebedev🇫🇮 · António P. Morais🇵🇹 · Vinícius Oliveira🇵🇹 · Roman Pasechnik🇸🇪
We study the Higgs boson decay into dark matter (DM) in the framework of freeze-in at stronger coupling. Even though the Higgs-DM coupling is significant, up to order one, DM does not thermalize due to the Boltzmann suppression of its production at low temperatures. We find that this mechanism leads to observable Higgs decay into invisible final states with the branching fraction of 10% and below, while producing the correct DM relic abundance. This applies to the DM masses down to the MeV scale, which requires a careful treatment of the hadronic production modes. For DM masses below the muon threshold, the Boltzmann suppression is not operative and the freeze-in nature of the production mechanism is instead guaranteed by the smallness of the electron Yukawa coupling. As a result, MeV DM with a significant coupling to the Higgs boson remains non-thermal as long as the reheating temperature does not exceed $O (100)$ MeV. Our findings indicate that there are good prospects for observing light non-thermal DM via invisible Higgs decay at the LHC and FCC.
hep-phhep-thJHEP(2025)·19 citations
18*
On the scalar $π K$ form factor beyond the elastic region
Frederic Noël🇨🇭 · Leon von Detten🇩🇪 · Christoph Hanhart🇩🇪 · Martin Hoferichter🇨🇭 · Bastian Kubis🇩🇪
Pion-kaon ( $π K$ ) final states, often appearing in heavy-particle decays at the precision frontier, are important for Standard-Model tests, to describe crossed channels with exotic states, and for spectroscopy of excited kaon resonances. We construct a representation of the $π K$ $S$ -wave form factor using the elastic $π K$ scattering phase shift via dispersion relations in the elastic region and extend this model into the inelastic region using resonance exchange, while maintaining unitarity and the correct analytic structure. As a first application, we successfully described the $τ \to K_{S} π ν_{τ}$ spectrum to not only achieve a better distinction between $S$ - and $P$ -wave contributions, but also to provide an improved estimate of the $C P$ asymmetry produced by a tensor operator as well as the forward-backward asymmetry, both of which can be confronted with future data at Belle II.
hep-phhep-exnucl-thSciPost Phys.Proc.(2025)·0 citations
19*
Constraining the hidden-charm pentaquark predictions and discriminating the $P_{c} (4440)$ and $P_{c} (4457)$ spins through the effective range expansion
Fang-Zheng Peng🇨🇳 · Li-Sheng Geng🇨🇳 · Ju-Jun Xie🇨🇳
The Weinberg compositeness criterion dictates that a pure shallow bound state is characterized by a large scattering length $a_{0} ≫ O (1/ β)$ and a positive effective range $r_{0}$ that naturally scales to the size of $O (1/ β)$ , where $1/ β$ signifies the interaction range. In constructing the contact-range effective field theory (EFT) up to the next-to-leading order to describe the pentaquarks $P_{c} (4312)$ , $P_{c} (4440)$ , and $P_{c} (4457)$ observed by the LHCb collaboration in 2019, we match the effective range $r_{0}$ at single-channel situation for these pentaquarks with the low-energy couplings within the EFT framework. Three different schemes are used to connect the couplings with the effective range. We find positive effective ranges $r_{0}$ of the natural size of $O (1/ β)$ for the spin configurations $J^{P} = \frac{3}{2}^{-}$ for $P_{c} (4440)$ and $J^{P} = \frac{1}{2}^{-}$ for $P_{c} (4457)$ within the molecular $D ˉ^{*} Σ_{c}$ description. Additionally, predictions from the power counting for low-energy couplings or Wilsonian coefficients suggest that, under heavy quark spin symmetry, the broad $P_{c} (4380)$ resonance, discovered by the LHCb collaboration in 2015, when considered as part of the single-channel $D ˉ^{(*)} Σ_{c}^{(*)}$ molecular system alongside $P_{c} (4312)$ , $P_{c} (4440)$ , and $P_{c} (4457)$ , has a mass of approximately $4376$ $MeV$ .
hep-phnucl-thPRD(2025)·8 citations
20*
Chiral perturbation theory
Ulf-G. Meißner🇩🇪
In the limit of vanishing up, down and strange quark masses, QCD exhibits a chiral symmetry. This symmetry is broken spontaneously to its vector subgroup, giving rise to Goldstone bosons. These acquire a small mass through the explicit chiral symmetry breaking for non-vanishing quark masses. The consequences of these broken symmetries can be investigated in a suitably tailored effective field theory called chiral pertubation theory. It admits a perturbative expansion in the external momenta and the Goldstone boson masses and can be systematically analyzed in terms of a loop expansion. The appearing ultraviolet divergences in loop diagrams can be dealt with order-by-order through the Goldstone boson contact interactions. Matter fields like the lowest-lying baryons can also included, leading to a rich and testable phenomenology of low-energy QCD.
hep-phhep-exhep-thnucl-ex+1Encyclopedia of Particle Physics(2026)·10 citations
21*
Testing tree level TeV scale seesaw scenarios in $μ$ TRISTAN
Arindam Das🇯🇵 · Jinmian Li🇨🇳 · Sanjoy Mandal🇰🇷 · Takaaki Nomura🇨🇳 · Rao Zhang🇨🇳
We investigate TeV scale seesaw scenarios at $μ^{+} e^{-}$ and $μ^{+} μ^{+}$ colliders in the $μ$ TRISTAN experiment. In minimal type-I seesaw scenario we consider two generations of Standard Model (SM) singlet heavy Majorana type Right Handed Neutrinos (RHNs) which couples with SM gauge bosons through light-heavy neutrino mixing. We discuss the prospects of probing heavy neutrinos via the processes such as $μ^{+} e^{-} \to ν N_{i} \to e^{+} j j ν$ or $μ^{-} j j ν$ for $s = 346$ ~GeV and $1 ab^{- 1}$ luminosity. Studying these process, we estimate limits on the light-heavy neutrino mixing angles as a function of heavy neutrino mass, which could be two orders of magnitude stronger than electroweak precision data. Further, we study the effect of doubly charged scalar boson $(H^{++})$ from the type-II seesaw scenario in $μ^{+} μ^{+}$ collision at $s = 2$ TeV. In this case we consider $μ^{+} μ^{+} \to ℓ_{i}^{+} ℓ_{j}^{+}$ and $μ^{+} μ^{+} \to H^{++} Z / γ$ processes followed by the same sign dilepton decay of $H^{++}$ . We find that events involving $e^{+} e^{+}$ among these final states can probe the neutrino mass ordering in $μ$ TRISTAN experiment at 5 $σ$ significance. In addition to that we study the production of positively charged triplet fermion in $μ$ TRISTAN following $μ^{+} μ^{+} \to μ^{+} Σ^{+}$ process where $Σ^{+}$ decays into $μ^{+} j j$ mode through $Z$ boson exchange. Considering a triplet at 1 TeV and studying SM backgrounds we estimate the discovery potential of $μ^{+} μ^{+} j j$ signal at $μ$ TRISTAN with respect to projected luminosity.
hep-phhep-exPRD(2025)·24 citations
22*
NLO EW corrections to tau pair production via photon fusion in Pb-Pb ultraperipheral collision
Jun Jiang🇨🇳 · Peng-Cheng Lu🇨🇳 · Zong-Guo Si🇨🇳 · Han Zhang🇨🇳 · Xin-Yi Zhang🇨🇳
We study the next-to-leading order (NLO) electroweak (EW) corrections to the $γ γ \to τ^{+} τ^{-}$ process in Pb-Pb ultraperipheral collision (UPC). We find that the EW correction $δ σ_{EW}$ decreases the total cross section $σ_{NLO} = σ_{LO} + δ σ_{EW}$ by -3\% at Pb-Pb center-of-mass energy $s_{N N} = 5.02$ TeV. The weak correction plays significant role whose contribution is about -4 times of that of QED. The CMS and ATLAS collaborations use the reaction $γ γ \to τ^{+} τ^{-}$ in Pb-Pb and proton-proton UPC to constrain tau's anomalous magnetic moment $a_{τ}$ . By parameterizing the $γ τ τ$ vertex with two form factors $F_{1, 2}$ , the cross section can be written as $σ_{a_{τ}} = σ_{LO} + δ σ_{a_{τ}}$ , where $δ σ_{a_{τ}}$ is proportional to $a_{τ}$ . The impact of NLO EW corrections on $a_{τ}$ bounds in Pb-Pb UPC is limited, as the current experimental bounds are loose. We also find that various differential distributions of the two ratios $d σ_{NLO} / d σ_{LO}$ and $d σ_{a_{τ}} / d σ_{LO}$ have different lineshapes. This work is significant to precisely study the interaction of $γ τ τ$ via $γ γ \to τ^{+} τ^{-}$ process.
hep-phPRD(2025)·7 citations
23*
Numerical analysis of melting domain walls and their gravitational waves
I. Dankovsky🇷🇺 · S. Ramazanov🇷🇺 · E. Babichev🇫🇷 · D. Gorbunov🇷🇺 · A. Vikman🇨🇿
We study domain walls (DWs) arising in field theories where $Z_{2}$ -symmetry is spontaneously broken by a scalar expectation value decreasing proportionally to the Universe temperature. The energy density of such melting DWs redshifts sufficiently fast not to overclose the Universe. For the first time, evolution of melting DWs and the resulting gravitational waves (GWs) is investigated numerically using lattice simulations. We show that formation of closed melting DWs during radiation domination is much more efficient compared to the scenario with constant tension DWs. This suggests that it can be the main mechanism responsible for reaching the scaling regime similarly to the case of cosmic strings. However, the scaling behaviour of melting DWs is observed, provided only that the initial scalar field fluctuations are not very large. Otherwise, simulations reveal violation of the scaling law, potentially of the non-physical origin. The spectrum of GWs emitted by melting DWs is also significantly different from that of constant tension DWs. Whether the system has reached scaling or not, the numerical study reveals a GW spectrum described in the infrared by the spectral index $n \approx 1.6$ followed by the causality tail. We attribute the difference from the value $n = 2$ predicted in our previous studies to a finite lifetime of the DW network. Notably, the updated index is still in excellent agreement with the recent findings by pulsar timing arrays, which confirms that melting DWs can be responsible for the observed (GW) signal. We also point out that results for evolution of melting DWs in the radiation-dominated Universe are applicable to constant tension DW evolution in the flat spacetime.
hep-phastro-ph.COhep-thJCAP(2025)·23 citations
24*
Prospects for Axion Dark Matter Searches at LISA-like Interferometers
Yue-Hui Yao🇨🇳 · Tingyuan Jiang🇨🇳 · Yong Tang🇨🇳
Axion or axionlike particles are one of the leading candidates for dark matter. Because of its tiny coupling with photons, axion dark matter in the background can induce distinct phase velocities for light with different parity, an effect known as birefringence. Here, we propose a modification to the polarization state of the interspacecraft laser link in LISA-like interferometers to make them sensitive to this birefringence effect. We discuss the prospects of using the Sagnac combinations to search for axion dark matter and derive the corresponding sensitivity. With this setup, we show that next-generation laser interferometers in space would have promising sensitivities on the axion-photon coupling with axion mass around $1 0^{- 19} - 1 0^{- 14} eV$ .
hep-phastro-ph.COPRD(2025)·15 citations
25*
Variational inference for pile-up removal at hadron colliders with diffusion models
Malte Algren🇨🇭 · Tobias Golling🇨🇭 · Christopher Pollard🇬🇧 · John Andrew Raine🇨🇭
In this paper, we present a novel method for pile-up removal of $pp$ interactions using variational inference with diffusion models, called vipr. Instead of using classification methods to identify which particles are from the primary collision, a generative model is trained to predict the constituents of the hard-scatter particle jets with pile-up removed. This results in an estimate of the full posterior over hard-scatter jet constituents, which has not yet been explored in the context of pile-up removal, yielding a clear advantage over existing methods especially in the presence of imperfect detector efficiency. We evaluate the performance of vipr in a sample of jets from simulated $t t ˉ$ events overlain with pile-up contamination. vipr outperforms softdrop and has comparable performance to puppiml in predicting the substructure of the hard-scatter jets over a wide range of pile-up scenarios.
hep-phcs.LGPRD(2025)·4 citations
26*
Can $1/ N_{c}$ corrections be treated in the Pomeron calculus?
Eugene Levin (Tel Aviv U.)🇮🇱
The main goal of the paper is to show that we can treat the $1/ N_{c}$ QCD corrections in the Pomeron calculus. We develop the one dimensional model which is a simplification of the QCD approach that includes $\pom \to 2 \pom$ , $2 \pom \to \pom$ and $2 \pom \to 2 \pom$ vertices and gives the description of the high energy interaction, both in the framework of the parton cascade and in the Pomeron calculus. In this model we show that the scattering amplitude can be written as the sum of Green's function of $n$ Pomeron exchanges $G_{n \pom} \propto e^{ω_{n} \Y}$ with $ω_{n} = κ n^{2}$ at $κ ≪ 1$ . This means that choosing $κ = 1/ N_{c}^{2}$ we can reproduce the intercepts of QCD in $1/ N_{c}$ order. The scattering amplitude is an asymptotic series that cannot be sum using Borel approach. We found a general way of summing such series. In addition to the positive eigenvalues we found the set of negative eigenvalues which corresponds to the partonic description of the scattering amplitude. Using Abramowsky, Gribov and Kancheli cutting rules we found the multiplicity distributions of the produced dipoles as well as their entropy $S_{E}$ .
hep-phEPJC(2025)·1 citation
27*
Event generation with Sherpa 3
Enrico Bothmann🇩🇪 · Lois Flower🇬🇧 · Christian Gütschow🇬🇧 · Stefan Höche🇺🇸 · Mareen Hoppe🇩🇪 · Joshua Isaacson🇺🇸 · Max Knobbe🇩🇪 · Frank Krauss🇬🇧 · Peter Meinzinger🇬🇧 · Davide Napoletano🇮🇹 · Alan Price🇵🇱 · Daniel Reichelt🇬🇧 and 3 other authors
Sherpa is a general-purpose Monte Carlo event generator for the simulation of particle collisions in high-energy collider experiments. We summarise new developments, essential features, and ongoing improvements within the Sherpa 3 release series. Physics improvements include higher-order electroweak corrections, simulations of photoproduction and hard diffraction at NLO QCD, heavy-flavour matching in NLO multijet merging, spin-polarised cross section calculations, and a new model of colour reconnections. In addition, the modelling of hadronisation, the underlying event and QED effects in both production and decay has been improved, and the overall event generation efficiency has been enhanced.
hep-phhep-exJHEP(2024)·123 citations
28*
Ultraheavy multiscattering dark matter: DUNE, CYGNUS, kilotonne detectors, and tidal streams
Harsh Aggarwal🇮🇳 · Nirmal Raj🇮🇳
In direct searches of dark matter, multi-scatter signatures are now being sought to probe scattering cross sections that are large enough to make the detector optically thick to incident particles. We provide some significant updates to the multi-scatter program. Using considerations of energy deposition, we derive the reaches in cross section and mass of various proposed large-volume detectors: a kilotonne fiducial mass "module of opportunity" at DUNE, a kilotonne xenon detector suggested for neutrinoless double beta decay, the gaseous detector CYGNUS, and the dark matter detectors XLZD and Argo. Where the velocity vector can be reconstructed event-by-event, the Galactic dark matter velocity distribution may be inferred. We exploit this to show that halo substructure such as tidal streams can be picked up if they make up about 10% of the local dark matter density.
hep-phastro-ph.HEhep-exPRD(2025)·6 citations
29*
Spin Trio: a dark matter scenario
Mohammad Hossein Rahimi Abkenar🇮🇷 · Ahmad Mohamadnejad🇮🇷 · Reza Sepahvand🇮🇷
We investigate a beyond Standard Model (SM) featuring five new fields. Four fields encompassing three distinct spin states - scalar ( $S$ ), spinor ( $ψ^{1, 2}$ ), and vector ( $V_{μ}$ ) - together form the multi-component dark matter (DM), while the fifth (scalar) field ( $ϕ$ ) carries a unit charge under a dark $U_{D} (1)$ gauge symmetry, enabling SM-DM interactions via the Higgs portal. Although the model maintains classical scale invariance, loop effects break electroweak symmetry. The parameter space is constrained by scale invariance, DM relic density, and direct detection results. Our study aims to identify feasible model regions and evaluate detectability in future experiments. We analyze processes like DM annihilations, semi-annihilations, and conversions, integrating them into Boltzmann equations to calculate DM abundances. Random parameter scans reveal regions compatible with current data, including constraints from direct detection experiments like XENONnT and PandaX-4T . Our results show the model's viability across a broad range of DM masses.
hep-phPRD(2025)·3 citations
30*
Bayesian analyses of the A2HDM with low-mass scalars
Antonio M. Coutinho🇪🇸 · Anirban Karan🇪🇸 · Víctor Miralles🇬🇧 · Antonio Pich🇪🇸
Two-Higgs-doublet models come with an augmented parameter space which allows them to possibly solve some of the shortcomings of the Standard Model, and opens the window to a plethora of new phenomena to be discovered. The introduction of scalar-mediated tree-level flavour-changing neutral currents may be tackled with the imposition of extra symmetries on the model or, alternatively, by demanding a strict proportionality between the flavour-changing couplings and fermion mass matrices. The latter is the very idea behind the Aligned-Two-Higgs-Doublet Model (A2HDM). The coefficients that govern such proportionality are, in general, complex and, therefore, possible new sources of CP violation, a calling card of this class of models. We present here the results of new state-of-the-art analyses of the A2HDM where, in particular, we ascertain whether current data allows the A2HDM to accommodate extra scalars lighter than the 125 GeV Higgs boson. To this effect, we make use of theoretical constraints, bounds from Higgs searches at the LHC and LEP, electroweak precision observables, and a set of flavour observables, all globally combined within HEPfit, a software with a Bayesian Markov Chain Monte Carlo approach to statistical inference. Focusing on the light-pseudoscalar scenario, we find a region of parameter space compatible with all the constraints we impose.
hep-phPoS(2025)·3 citations
31*
Entanglement as a probe of hadronization
Jaydeep Datta🇺🇸 · Abhay Deshpande🇺🇸 · Dmitri E. Kharzeev🇺🇸 · Charles Joseph Naïm🇺🇸 · Zhoudunming Tu🇺🇸
Recently, it was discovered that the proton structure at high energies exhibits maximal entanglement. This leads to a simple relation between the proton's parton distributions and the entropy of hadrons produced in high-energy inelastic interactions that has been experimentally confirmed. In this letter, we extend this approach to the production of jets. Here, the maximal entanglement predicts a relation between the jet fragmentation function and the entropy of hadrons produced in jet fragmentation. We test this relation using the ATLAS Collaboration data on jet production at the Large Hadron Collider and find good agreement between the prediction based on maximal entanglement within the jet and the data. This study represents the first use of the quantum entanglement framework in the experimental study of the hadronization process, offering a new perspective on the transition from perturbative to non-perturbative QCD. Our results open the door to a more comprehensive understanding of the quantum nature of hadronization.
hep-phhep-exnucl-exnucl-thPRL(2025)·28 citations
32*
No-quenching baseline for energy loss signals in oxygen-oxygen collisions
Jannis Gebhard🇩🇪 · Aleksas Mazeliauskas🇩🇪 · Adam Takacs🇩🇪
In this work, we perform computations of inclusive jet, and semi-inclusive jet-hadron cross sections for minimum bias oxygen-oxygen collisions at RHIC and LHC collision energies. We compute the no-quenching baseline for the jet nuclear modification factor $R_{AA}$ and jet-, and hadron-triggered semi-inclusive nuclear modification factors $I_{AA}$ . We do this with state-of-the-art nuclear parton distribution functions (nPDFs), next-to-leading-order matrix elements, parton shower, and hadronization. We observe deviations from unity due to cold-nuclear matter effects, even without quenching. We demonstrate that the parton distribution uncertainties constitute a significant obstacle in detecting energy loss in small collision systems. Hadron-triggered observables are particularly sensitive to uncertainties due to correlations between the trigger and analyzed particles. For jet-triggered $I_{AA}$ , there exists a kinematic window in which nPDF and scale uncertainties cancel dramatically while showing little sensitivity to parton shower and hadronization models, addressing a major limiting factor for energy loss discovery in small systems.
hep-phnucl-exnucl-thJHEP(2025)·19 citations
33*
Scalar relics from the hot Big Bang
David Cyncynates🇺🇸 · Olivier Simon🇺🇸
In this Letter, we motivate the fact that couplings between a scalar field and the Standard Model with strengths $1 0^{- 6} (m_{ϕ} / eV)^{- 1/4}$ relative to gravity yield the total measured cosmological dark matter abundance over a broad mass range of $1 0^{- 12}$ to $1 0^{14} eV$ . Remarkably, this result holds with minimal sensitivity to whether the scalar couples to electrons, photons, hadrons, or other particles at laboratory energy scales, thereby linking fifth force experiments to the search for dark matter.
hep-phastro-ph.COhep-exPRL(2025)·20 citations
34*
Predicting the Dark Matter -- Baryon Abundance Ratio
Abhishek Banerjee🇺🇸 · Dawid Brzeminski🇺🇸 · Anson Hook🇺🇸
We discuss relaxation solutions to the dark matter - baryon coincidence problem in the context of QCD axion dark matter. In relaxation solutions, a moduli dynamically adjusts the mass of dark matter and baryons until their energy densities are $O (1)$ the same. Because the QCD axion is heavily connected to QCD, scanning the QCD axion mass inherently also scans the proton mass. In the context of relaxation solutions, this implies that the ratio of dark matter to baryon abundances ( $Ω_{DM} / Ω_{B}$ ) is a ratio of beta functions showing that these models can only accommodate discrete values of $Ω_{DM} / Ω_{B}$ thereby ``predicting" the ratio of the dark matter to baryon abundances. The original composite axion model has only a single integer degree of freedom $N$ , the size of the gauge group, and we show that when $N = 8$ the observed value of $Ω_{DM} / Ω_{B} = 5.36$ is reproduced to within its percent level error bars. Novel tests of this model include more precise measurements of $Ω_{DM} / Ω_{B}$ , a better lattice determination of the dependence of the proton mass on the high energy QCD gauge coupling, as well as more traditional tests such as fifth force experiments.
hep-phPRD(2026)·11 citations
35*
Eliminating Incoherent Noise: A Coherent Quantum Approach in Multi-Sensor Dark Matter Detection
Jing Shu🇨🇳 · Bin Xu🇨🇳 · Yuan Xu🇨🇳
We propose a novel dark matter detection scheme by leveraging quantum coherence across a network of multiple quantum sensors. This method effectively eliminates incoherent background noise, thereby significantly enhancing detection sensitivity. This is achieved by performing a series of basis transformation operations, allowing the coherent signal to be expressed as a combination of sensor population measurements without introducing background noise. We present a comprehensive analytical analysis and complement it with practical numerical simulations. These demonstrations reveal that signal strength is enhanced by the square of the number of sensors, while noise, primarily due to operational infidelity rather than background fluctuations, increases only linearly with the number of sensors. Our approach paves the way for next-generation dark matter searches that optimally utilize an advanced network of sensors and quantum technologies.
hep-phhep-exquant-ph11 citations
36*
Hybrid quantum-classical approach for combinatorial problems at hadron colliders
Jacob L. Scott🇺🇸 · Zhongtian Dong🇺🇸 · Taejoon Kim🇺🇸 · Kyoungchul Kong🇺🇸 · Myeonghun Park🇰🇷 · Heechan Yi🇰🇷 · Willie Aboumrad · Ananth Kaushik🇺🇸 · Martin Roetteler🇺🇸
In recent years, quantum computing has drawn significant interest within the field of high-energy physics. We explore the potential of quantum algorithms to resolve the combinatorial problems in particle physics experiments. As a concrete example, we consider top quark pair production in the fully hadronic channel at the Large Hadron Collider. We investigate the performance of various quantum algorithms such as the Quantum Approximation Optimization Algorithm (QAOA), a feedback-based algorithm (FALQON) and a variational quantum imaginary time evolution algorithm (VarQITE). We demonstrate that the efficiency for selecting the correct pairing is greatly improved by utilizing quantum algorithms over conventional kinematic methods. Furthermore, we observe that gate-based universal quantum algorithms perform on par with machine learning techniques and either surpass or match the effectiveness of quantum annealers. Our findings reveal that quantum algorithms not only provide a substantial increase in matching efficiency but also exhibit adaptability and the potential for scalability, making them promising candidates for a variety of high-energy physics applications, as quantum hardware technology matures. Moreover, quantum algorithms eliminate the extensive training processes needed by classical machine learning methods, enabling real-time adjustments based on individual event data.
hep-phquant-ph5 citations
37*
Dilepton production from moaton quasiparticles
Zohar Nussinov🇺🇸 · Michael C. Ogilvie🇺🇸 · Laurin Pannullo🇩🇪 · Robert D. Pisarski🇺🇸 · Fabian Rennecke🇩🇪 · Stella T. Schindler🇺🇸 · Marc Winstel🇩🇪
The phase diagram of QCD may contain a moat regime in a large region of temperature $T$ and chemical potential $μ \neq = 0$ . A moat regime is characterized by quasiparticle moatons (pions) whose energy is minimal at nonzero spatial momentum. At $μ \neq = 0$ , higher mass dimension operators play a critical role in a moat regime. At dimension six, there are nine possible gauge invariant couplings between scalars and photons. For back-to-back dilepton production, only one operator contributes, which significantly enhances production near a moat threshold. This enhancement is an experimental signature of moatons.
hep-phnucl-thPRL(2025)·17 citations
38*
Effective field theory for radiative corrections to charged-current processes II: Axial-vector coupling
Vincenzo Cirigliano🇺🇸 · Wouter Dekens🇺🇸 · Emanuele Mereghetti🇺🇸 · Oleksandr Tomalak🇺🇸
We discuss the hadronic structure-dependent radiative corrections to the axial-vector coupling that controls single-nucleon weak charged-current processes -- commonly denoted by $g_{A}$ . We match the Standard Model at the GeV scale onto chiral perturbation theory at next-to-leading order in the one-nucleon sector, in the presence of electromagnetic and weak interactions. As a result, we provide a representation for the corrections to $g_{A}$ in terms of infrared finite convolutions of simple kernels with the single-nucleon matrix elements of time-ordered products of two and three quark bilinears (vector, axial-vector, and pseudoscalar). We discuss strategies to determine the required non-perturbative input from data, lattice-QCD (+QED), and possibly hadronic models. This work paves the way for a precise comparison of the values of the ratio $g_{A} / g_{V}$ extracted from experiment and from lattice-QCD, which constrain physics beyond the Standard Model.
↳ nucl-thhep-exhep-phnucl-exPRD(2025)·22 citations
39*
Self-Gravity Effects of Ultralight Boson Clouds Formed by Black Hole Superradiance
Taillte May🇨🇦 · William E. East🇨🇦 · Nils Siemonsen🇺🇸
Oscillating clouds of ultralight bosons can grow around spinning black holes through superradiance, extracting energy and angular momentum, and eventually dissipating through gravitational radiation. Gravitational wave detectors like LIGO, Virgo, KAGRA, and LISA can thus probe the existence of ultralight bosons. In this study, we use fully general-relativistic solutions of the black hole-boson cloud systems to study the self-gravity effects of scalar and vector boson clouds, making only the simplifying assumption that the spacetime is axisymmetric (essentially corresponding to taking an oscillation average). We calculate the self-gravity shift in the cloud oscillation frequency, which determines the frequency evolution of the gravitational wave signal, finding that this effect can be up to twice as large in the relativistic regime compared to non-relativistic estimates. We use this to improve the superrad waveform model, and estimate that this reduces the theoretical phase error to a few cycles over the characteristic timescale of the gravitational wave emission timescale for the louder vector boson signals. We also perform an analysis of the spacetime geometry of these systems, calculating how the cloud changes the innermost stable circular orbit and light-ring around the black hole.
↳ gr-qcastro-ph.HEhep-phhep-thPRD(2025)·25 citations
40*
Towards alleviating the $H_{0}$ and $S_{8}$ tensions with Early Dark Energy - Dark Matter drag
Théo Simon🇫🇷 · Tal Adi🇮🇱 · José Luis Bernal🇪🇸 · Ely D. Kovetz🇮🇱 · Vivian Poulin🇫🇷 · Tristan L. Smith🇺🇸
Early dark energy, an additional component of dark energy active in the decade of redshift before recombination, has emerged as one of the most effective models at reducing the $H_{0}$ tension between direct measurement of the Hubble parameter $H_{0}$ in the late-universe and the $Λ$ CDM prediction when calibrated on Planck. However, it requires a slight increase in the dark matter density $ω_{cdm}$ and primordial tilt $n_{s}$ that worsens the $S_{8}$ tension between measurements of weak gravitational lensing at low redshifts and the Planck/ $Λ$ CDM prediction. Using a phenomenological fluid model, we investigate whether the inclusion of a drag term between dark matter and early dark energy can compensate for the effect of the increase in power at small-scales, such that both $H_{0}$ and $S_{8}$ tensions are simultaneously alleviated. We find that this works if the drag term is dynamically relevant in the post-recombination universe. However, a drag term active before or just around the time at which the early dark energy contribution to the energy density is maximum is significantly constrained due to its impact on the matter perturbations before recombination, and the subsequent modifications to the cosmic microwave background power spectra.
↳ astro-ph.COhep-phPRD(2025)·31 citations
41*
Quantum gravity with purely virtual particles from asymptotically local quantum field theory
Damiano Anselmi🇮🇹
We investigate the relationship between nonlocal and local quantum field theories, and search for a viable notion of "local limit" to relate the unitary models. In Euclidean space it is relatively easy to have nonlocal theories with well-behaved local limits. In Minkowski spacetime, instead, singular behaviors are generically expected. Relaxing some assumptions on the "form factors" considered in the literature, we identify a class of models that have regular local limits in Minkowski spacetime. We call the models "asymptotically local" quantum field theories (AL-QFTs) and show that their limits are theories with physical and purely virtual particles (PVPs). In the bubble diagram, the nonlocal deformation generates PVPs straightforwardly. In the triangle diagram, it does so possibly up to multi-threshold corrections, which may be adjusted by tuning the deformation itself. We also build an asymptotically local deformation of quantum gravity with purely virtual particles. AL-QFT can serve various purposes, such as suggesting innovative approaches to off-shell physics, providing an alternative formulation for theories with PVPs, or smoothing out nonanalytic behaviors. We discuss its inherent arbitrariness and the implications for renormalizability.
↳ hep-thgr-qchep-phEPJC(2025)·3 citations
42*
CaloChallenge 2022: A Community Challenge for Fast Calorimeter Simulation
Claudius Krause🇦🇹 · Michele Faucci Giannelli🇮🇹 · Gregor Kasieczka🇩🇪 · Benjamin Nachman🇺🇸 · Dalila Salamani🇨🇭 · David Shih🇺🇸 · Anna Zaborowska🇨🇭 · Oz Amram🇺🇸 · Kerstin Borras🇩🇪 · Matthew R. Buckley🇺🇸 · Erik Buhmann🇩🇪 · Thorsten Buss🇩🇪 and 57 other authors
We present the results of the "Fast Calorimeter Simulation Challenge 2022" - the CaloChallenge. We study state-of-the-art generative models on four calorimeter shower datasets of increasing dimensionality, ranging from a few hundred voxels to a few tens of thousand voxels. The 31 individual submissions span a wide range of current popular generative architectures, including Variational AutoEncoders (VAEs), Generative Adversarial Networks (GANs), Normalizing Flows, Diffusion models, and models based on Conditional Flow Matching. We compare all submissions in terms of quality of generated calorimeter showers, as well as shower generation time and model size. To assess the quality we use a broad range of different metrics including differences in 1-dimensional histograms of observables, KPD/FPD scores, AUCs of binary classifiers, and the log-posterior of a multiclass classifier. The results of the CaloChallenge provide the most complete and comprehensive survey of cutting-edge approaches to calorimeter fast simulation to date. In addition, our work provides a uniquely detailed perspective on the important problem of how to evaluate generative models. As such, the results presented here should be applicable for other domains that use generative AI and require fast and faithful generation of samples in a large phase space.
↳ physics.ins-detcs.LGhep-exhep-phRept.Prog.Phys.(2025)·89 citations
43*
Entanglement-enhanced AC magnetometry in the presence of Markovian noises
Thanaporn Sichanugrist🇯🇵 · Hajime Fukuda🇯🇵 · Takeo Moroi🇯🇵 · Kazunori Nakayama🇯🇵 · So Chigusa🇺🇸 · Norikazu Mizuochi🇯🇵 · Masashi Hazumi🇯🇵 · Yuichiro Matsuzaki🇰🇷
Entanglement is a resource to improve the sensitivity of quantum sensors. In an ideal case, using an entangled state as a probe to detect target fields, we can beat the standard quantum limit by which all classical sensors are bounded. However, since entanglement is fragile against decoherence, it is unclear whether entanglement-enhanced metrology is useful in a noisy environment. Its benefit is indeed limited when estimating the amplitude of DC magnetic fields under the effect of parallel Markovian decoherence, where the noise operator is parallel to the target field. In this paper, on the contrary, we show an advantage to using an entanglement over the classical strategy under the effect of parallel Markovian decoherence when we try to detect AC magnetic fields. We consider a scenario to induce a Rabi oscillation of the qubits with the target AC magnetic fields. Although we can, in principle, estimate the amplitude of the AC magnetic fields from the Rabi oscillation, the signal becomes weak if the qubit frequency is significantly detuned from the frequency of the AC magnetic field. We show that, by using the GHZ states, we can significantly enhance the signal of the detuned Rabi oscillation even under the effect of parallel Markovian decoherence. Our method is based on the fact that the interaction time between the GHZ states and AC magnetic fields scales as $1/ L$ to mitigate the decoherence effect where $L$ is the number of qubits, which contributes to improving the bandwidth of the detectable frequencies of the AC magnetic fields. Our results open up the way for new applications of entanglement-enhanced AC magnetometry.
↳ quant-phhep-exhep-phPRA(2025)·7 citations
44*
Millilensing induced systematic biases in parameterized tests of General Relativity
Anna Liu🇨🇳 · Rohit S. Chandramouli🇺🇸 · Otto A. Hannuksela🇨🇳 · Nicolás Yunes🇺🇸 · Tjonnie G. F. Li🇨🇳
Tests of general relativity (GR) can be systematically biased when our waveform models are inaccurate. We here study systematic biases in tests of general relativity induced by neglecting lensing effects for millilensed gravitational-wave signals, where the lens mass is typically in the $1 0^{3} M_{⊙}$ -- $1 0^{5} M_{⊙}$ range. In particular, we use a nested-sampling Bayesian parameter estimation and model selection analysis of a millilensed signal with an unlensed parameterized post-Einsteinian (ppE) recovery model. We find that the ppE model is significantly biased toward a detection of a deviation from general relativity at signal-to-noise ratios of 30 and higher, especially when the source is aligned with the lens mass (the lensing effect is pronounced) and when its total mass is low (the signal duration is long). We use a toy model and the linear signal and Laplace approximations to provide a semi-analytic explanation for the trends in the systematic errors found in the nested sampling analysis. Moreover, a Bayes factor analysis reveals that the (unlensed) ppE model is weakly favored over the (unlensed) GR model, and a fitting factor study shows there is a significant loss of signal-to-noise ratio when using the (unlensed) ppE model. This implies that although a parameter estimation study may incorrectly infer a deviation from general relativity, a residual signal-to-noise ratio test would reveal that the ppE model is not a good fit to the data. Thus, with current detectors, millilensing-induced systematic biases are unlikely to result in false positive detections of GR deviations.
↳ gr-qcastro-ph.HEhep-phPRD(2025)·12 citations
45*
Probing nuclear liquid-gas phase transition with isospin correlations
Michał Marczenko🇵🇱 · Krzysztof Redlich🇵🇱 · Chihiro Sasaki🇵🇱
We investigate the fluctuations of the net-baryon number near the critical point of the liquid-gas phase transition. We use the parity doublet model in the mean-field approximation fixed to the zero-temperature properties of nuclear matter to account for critical behavior. We explicitly calculate the fluctuations of the net-proton and net-neutron numbers as well as their correlations in the isospin-symmetric matter. We focus on the qualitative properties and systematics of the first- to fourth-order susceptibilities and their ratios. We demonstrate that the fluctuations of net-proton number do not reflect the total net-baryon number fluctuations in the vicinity of the nuclear liquid-gas phase transition. We also study the behavior of the baryon and proton number factorial cumulants. We highlight the importance of the non-trivial correlations between protons and neutrons.
↳ nucl-thhep-phPRC(2025)·7 citations
46*
Redshift-space distortion constraints on the neutrino mass and models to alleviate the Hubble tension
Yo Toda🇯🇵 · Osamu Seto🇯🇵
We discuss the neutrino mass and Hubble tension solutions and examine their effects on the redshift-space distortion (RSD) observations. An analysis with RSD data indicates smaller amplitude of perturbation. Including RSD data results in a slightly weaker upper limit on the neutrino mass than that derived for data without RSD, which is common in other extended models too. We have evaluated the impacts of RSD observations on some extended models, including the varying electron mass model, a time-dependent dark energy model with two parameter equations of state (EOS), and a model where the number of neutrino species is free. When we estimate the cosmological parameters for data including RSD, we found that the EOS parameter for dark energy is larger than that of the cosmological constant, and the effective number of neutrino species is smaller than the standard value, which infers a smaller present Hubble parameter $H_{0}$ . From the viewpoint of cosmological tensions, the varying electron mass model with nonzero neutrino mass option looks promising to relax the Hubble tension and the $S_{8}$ tension simultaneously.
↳ astro-ph.COhep-phPRD(2025)·10 citations
47*
Dark Radiation production in axion misalignment mechanisms and the cosmological tensions
José María Pérez-Poyatos🇪🇸 · Veronica Sanz🇪🇸
We investigate the production of dark radiation (DR) from axions and axion-like particles (ALPs) as potential origins of dark matter. Focusing on the dark matter misalignment mechanism, we examine non-thermal, pre-inflationary scenarios that could lead to the generation of DR. A key part of our analysis involves a Bayesian approach to confront ALP parameter space with current cosmological data. Additionally, we explore whether DR production could offer solutions to persistent cosmological anomalies, particularly those related to the Hubble constant $H_{0}$ tension and the $S_{8}$ parameter discrepancy. Our findings aim to shed new light on the role of ALPs in addressing these open issues in cosmology.
↳ astro-ph.COhep-ph0 citations
48*
A Gaussian Process Generative Model for QCD Equation of State
Jiaxuan Gong🇺🇸 · Hendrik Roch🇺🇸 · Chun Shen🇺🇸
We develop a generative model for the nuclear matter equation of state at zero net baryon density using the Gaussian Process Regression method. We impose first-principles theoretical constraints from lattice QCD and hadron resonance gas at high- and low-temperature regions, respectively. By allowing the trained Gaussian Process Regression model to vary freely near the phase transition region, we generate random smooth cross-over equations of state with different speeds of sound that do not rely on specific parameterizations. We explore a collection of experimental observable dependencies on the generated equations of state, which paves the groundwork for future Bayesian inference studies to use experimental measurements from relativistic heavy-ion collisions to constrain the nuclear matter equation of state.
↳ nucl-thhep-phPRC(2025)·11 citations
49*
Mean-field theory for self-interacting relativistic Luttinger fermions
Holger Gies🇩🇪 · Marta Picciau🇩🇪
We investigate a class of quantum field theories with relativistic Luttinger fermions and local self-interaction in scalar channels. For an understanding of possible low-energy phases, we first classify the set of mass terms arising from scalar fermion bilinears. For large flavor numbers, we show that each of our models features a coupling branch in which the theory is asymptotically free. In order to address the long-range behavior, we use mean-field theory which is exact in the limit of large flavor numbers. We identify two models which undergo dimensional transmutation, interconnecting the asymptotically free high-energy regime with an ordered low-energy phase sustaining a vacuum condensate. We also study the analytic structure of the Luttinger-fermionic propagator in the various possible gapped phases.
↳ hep-thhep-phPRD(2025)·4 citations
50*
Hypothesis tests and model parameter estimation on data sets with missing correlation information
Lukas Koch🇩🇪
Ideally, all analyses of normally distributed data should include the full covariance information between all data points. In practice, the full covariance matrix between all data points is not always available. Either because a result was published without a covariance matrix, or because one tries to combine multiple results from separate publications. For simple hypothesis tests, it is possible to define robust test statistics that will behave conservatively in the presence on unknown correlations. For model parameter fits, one can inflate the variance by a factor to ensure that things remain conservative at least up to a chosen confidence level. This paper describes a class of robust test statistics for simple hypothesis tests, as well as an algorithm to determine the necessary inflation factor for model parameter fits and Goodness of Fit tests and composite hypothesis tests. It then presents some example applications of the methods to real neutrino interaction data and model comparisons.
↳ stat.MEastro-ph.IMhep-phphysics.data-an+1PRD(2025)·4 citations
51*
The Three-Point Form Factor of $Tr ϕ^{3}$ to Six Loops
Benjamin Basso🇫🇷 · Lance J. Dixon🇺🇸 · Alexander G. Tumanov🇫🇷
We study the three-point form factor of the length-three half-BPS operator ( $Tr ϕ^{3}$ ) in planar $N = 4$ Super-Yang-Mills theory, using analyticity and integrability methods. We find that the functions describing the form factor in perturbation theory live in the same restrictive space of multiple polylogarithms as the one describing the form factor of the stress-tensor operator ( $Tr ϕ^{2}$ ). Furthermore, we find that the leading-order data in the collinear limit provided by the form factor operator product expansion (FFOPE) is enough to fix the form factor uniquely, at least through six loops. We perform various tests of our results using the subleading FFOPE corrections. We also analyze the form factor in the Regge limit where two Mandelstam invariants are large; we obtain a compact representation for the form factor in this limit which is valid to all orders in the coupling.
↳ hep-thhep-phJHEP(2025)·28 citations
52*
Entanglement Entropy is Elastic Cross Section
Ian Low🇺🇸 · Zhewei Yin🇺🇸
We present universal relations between entanglement entropy, which quantifies the quantum correlation between subsystems, and the elastic cross section, which is the primary observable for high energy particle scattering, by employing a careful formulation of wave packets for the incoming particles. For 2-to-2 elastic scattering with no initial entanglement and subdividing the system along particle labels, we show that both the Rényi and Tsallis entropies in the final states are directly proportional to the elastic cross section in unit of the transverse size for the initial wave packets, which is then interpreted as the elastic scattering probability. The relations do not depend on the underlying dynamics of the quantum field theory and are valid to all orders in coupling strengths. Furthermore, computing quantum correlations between momentum and non-kinematic data leads to entanglement entropies expressed as various semi-inclusive elastic cross sections. Our result gives rise to a novel ``area law'' for entanglement entropy in a two-body system.
↳ hep-thcond-mat.stat-mechhep-phnucl-th+1PRD(2025)·37 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.