HEP Phenomenology·hep-ph

Thu·Aug 6, 2026Thursday·August 6, 2026

32 papers—23 primary·9 cross-listed

01
Investigating the $P$ -wave $D K^{*}$ Molecular Interpretation of the $D_{s 1} (2700)$ via Its Strong Decays
Qing Lu🇨🇳 · ZheHao Zhu🇨🇳 · Cai Cheng🇨🇳 · Yin Huang🇨🇳
In this work, we investigate the possibility of interpreting the $D_{s 1} (2700)$ as a $P$ -wave $D K^{*}$ hadronic molecular state through a systematic study of its strong decay properties. Using the effective Lagrangian approach, we calculate the strong decay widths of the $D_{s 1} (2700)$ into the two-body final states $D K$ , $D^{*} K$ , $D_{s} η$ , and $D_{s}^{*} η$ , as well as the three-body $D π K$ channel. The coupling of the $D_{s 1} (2700)$ to its constituents, $D K^{*}$ , is constrained by the available experimental measurement of $R_{D_{s 1}} = Γ (D_{s 1} (2700) \to D^{*} K) /Γ (D_{s 1} (2700) \to D K) = 0.91 \pm 0.13 \pm 0.12$ . With the resulting coupling, the total decay width can be readily obtained and is found to be in good agreement with the experimental measurement, providing strong support for interpreting the $D_{s 1} (2700)$ as a $P$ -wave $D K^{*}$ molecular state. The experimentally unobserved $D_{s 1} (2700) \to D_{s}^{*} η$ decay channel provides a further test of this interpretation, as its predicted sizable decay width differs significantly from the conventional quark model prediction.
hep-ph0 citations
02
Moving a Detector to Probe New Neutrino Interactions: IWCD at Hyper-Kamiokande
Thomas Schwemberger🇯🇵 · Volodymyr Takhistov🇯🇵
Moving a detector through a beam with a spatially varying energy spectrum exposes the same target and apparatus to distinct incident spectra, enabling interaction spectroscopy. While movable neutrino detectors were put forth primarily to control systematic uncertainties, we show that detector motion enables probing the structure of fundamental interactions. We demonstrate this with the Intermediate Water Cherenkov Detector (IWCD), the movable detector of Hyper-Kamiokande in the J-PARC off-axis beam, considering neutrino non-standard interactions (NSI) as a benchmark. Exploiting ratios of neutral current to charged current event rates reduces common normalization uncertainties, while measurements at multiple off-axis positions can break degeneracies that persist for a single incident spectrum. Combining three off-axis positions and adopting a $5%$ correlated normalization uncertainty benchmark, we project $95%$ CL sensitivities to axial neutral current NSI of $- 0.07 ≲ ε_{μμ}^{u A} ≲ 0.06$ and vector NSI of $- 0.10 ≲ ε_{μμ}^{u V} ≲ 0.12$ , as well as for charged current NSI of $- 0.05 ≲ ε_{μμ}^{u d L} ≲ 0.05$ . Axial NSI, which do not contribute to the ordinary matter potential, are complementary to neutrino oscillation and high energy scattering measurements. More broadly, detector motion provides a new way to distinguish interactions with different energy dependence.
hep-phhep-ex0 citations
03
Language-Guided Hypotheses Generation for Sparse SMEFT Analyses
Ahmed Hammad🇰🇷 · Veronica Sanz🇪🇸
Global fits of the Standard Model Effective Field Theory are challenged by the large number of operators, while any given database constrains only a small subset. Selecting relevant operator hypotheses therefore requires theoretical insight into operator correlations and the sensitivity of observables. We present llm4smeft, an open source framework that addresses this problem by combining a language model, fine-tuned on the SMEFT literature, with retrieval augmented generation based on quantitative summaries of SMEFiT package global fits. Given a set of observables, the framework proposes candidate relevant operators together with their corresponding Fisher information, while retrieval ensures that model outputs are grounded in existing fit results whenever available. The framework runs in an interactive mode in which accepted hypotheses are stored in a growing knowledge base. We publicly release the llm4smeft package together with the fine-tuned language model, in which the entire framework runs locally, requiring neither internet access nor paid cloud services.
hep-phhep-exhep-th0 citations
04
Consistent Thermal Resummation and Phase Transitions with 2PI Methods
Amitayus Banik🇰🇷 · Kimmo Kainulainen🇫🇮
We apply the two-particle irreducible (2PI) formalism as a framework for a consistent thermal resummation in studies of cosmological phase transitions. Considering a model with two mixing real scalar fields, we work within the Hartree approximation and renormalize the 2PI effective action, while introducing a connection to physical parameters. This yields the Hartree-resummed finite-temperature effective potential, which is valid for all temperatures and avoids the limitations of conventional methods based on the high-temperature approximation. With this potential, we study one- and two-step transitions within the model, and compare our results with those obtained using resummation schemes widely employed in the literature. Finally, we evaluate the gravitational wave spectrum generated from first-order phase transitions, demonstrating the impact of the choice of resummation scheme on the predicted spectrum.
hep-phastro-ph.COhep-th0 citations
05
Quarkoniumlike states above open-flavor thresholds in Born-Oppenheimer EFT
Nora Brambilla🇩🇪 · Roberto Bruschini🇺🇸 · Abhishek Mohapatra🇩🇪 · Fang-Zheng Peng🇩🇪 · Tommaso Scirpa🇩🇪
Many quarkoniumlike states have been observed above open-flavor thresholds, but their organization and internal structure remain unsettled. We study the isoscalar hidden-charm and hidden-bottom sectors in Born--Oppenheimer effective field theory (BOEFT), between the spin--isospin averaged $S + S$ and $S + P$ thresholds. At leading order, heavy-quark spin decouples, and the quarkonium static potential mixes through string breaking with the lowest tetraquark/open-flavor BO potentials of the same quantum numbers. These potentials are constrained by QCD symmetries, their short- and long-distance behavior, and lattice-QCD data. The only calibrated parameter is the lowest $1^{--}$ adjoint meson mass, fixed from the shallow multiplet associated with the $χ_{c 1} (3872)$ . Using $T$ -matrix, $K$ -matrix, and complex-scaling methods, we determine bound states and resonance poles, their masses, pole widths from the included nonstrange $S + S$ channels, normalized pole couplings, and prescription-dependent quarkonium--open-flavor composition measures. Uncoupled hybrid BOEFT multiplets are included as reference levels. The spectrum exhibits a common heavy-quark-spin-symmetry multiplet organization. Most poles are predominantly quarkonium resonances localized at short distances, with the largest open-flavor components closest to threshold. The same equations also generate shallow, spatially extended, open-flavor-dominated states with molecular long-distance characteristics. Their binding energies, radii, and small quarkonium components are highly sensitive to the adjoint meson mass, whereas the higher spectrum is more stable. Together with the hybrid reference levels, the spectrum provides multiplet assignments for most candidates. States not naturally accommodated point to the need for hidden-strange and $S + P$ tetraquark/open-flavor BO sectors and for hybrid--tetraquark and hybrid--quarkonium mixings.
hep-phhep-exhep-latnucl-th1 citation
06
Amnesia in the Axion Misalignment Landscape
Kierthika Chathirathas🇩🇪 · Cem Eröncel🇹🇷 · Mathieu Kaltschmidt🇪🇸 · Javier Redondo🇪🇸 · Kenichi Saikawa🇯🇵
Pre-inflationary axion cosmologies admit a broad range of initial velocities and angles that generate a landscape of misalignment histories, whose nonlinear fate and small-scale structure remain uncertain. We use lattice simulations to follow the QCD axion in the kinetic misalignment scenario through the QCD crossover into the non-relativistic regime, towards matter-radiation equality. In the meV mass range, this landscape contains a continuum of ''summit-landing" solutions sensitive to both the initial angle and velocity. Nonlinear fragmentation reduces the comoving axion number and modifies the relation between the misalignment history and present relic abundance. For sufficiently large axion masses, strong self-interactions drive the small-scale spectrum towards the attractor found for post-inflationary axions, so that distinct early histories can lead to similar late-time structures.
hep-phastro-ph.COhep-th2 citations
07
Bare effective potential and Goldstone boson anti-resummation
Stephen P. Martin🇺🇸
I discuss the evaluation of the effective potential and related quantities starting from bare perturbation theory followed by $MS$ renormalization. The advantages of this method include a simple new way of avoiding infrared problems associated with Goldstone bosons, by treating their bare masses as two-point interaction vertices instead of incorporating them into the propagators. Thus, only positive integer powers of the Goldstone-boson masses appear at every stage of calculation, completely avoiding the imaginary parts and singularities encountered in intermediate steps of previous resummation methods. This Goldstone boson anti-resummation approach is implemented using simple rules provided through three-loop order in terms of the master vacuum integrals. Explicit results are given for the Standard Model at three-loop order. The method is shown to give effective potential minimization conditions that are consistent with previous resummation methods, but in a form more directly useful for related future multi-loop calculations of observables in the tadpole-free scheme.
hep-ph0 citations
08
Pinpointing the Mechanism of Neutrinoless Weak Decays with Positrons
Julia Harz🇩🇪 · George A. Parker🇩🇪
Neutrinoless double beta decay is the flagship laboratory probe of a Majorana contribution to the neutrino mass. However, besides the standard mass mechanism other higher- dimensional lepton number-violating interactions can enter, or even dominate, this process. The corresponding positron-emitting neutrinoless modes, such as electron capture or double-positron emission, have long been considered out of reach experimentally, due to their naturally smaller rates. Recently, innovative detector technologies as used in the proposed NuDoubt++ experiment are changing the game. In this work, we explore how a positron- and electron-mode detector can be complementary in the search for new physics. Assuming an observation of neutrinoless double beta decay, we predict the expected discovery half-life for the positron-modes. Using half-life ratios, especially between the double beta and electron capture modes, we demonstrate how underlying long-range interactions can be distinguished, in particular to identify a purely right-handed leptonic current.
hep-ph0 citations
09
Open-Charm Vector Mesons in Hot and Dense Nuclear Matter
N. Er🇹🇷 · K. Azizi🇮🇷
We investigate the in-medium properties of the open-charm vector mesons $D_{s}^{*}$ and $D^{*}$ in hot and dense nuclear matter within the framework of finite-temperature and finite-density QCD sum rules. The analysis incorporates temperature- and density-dependent quark and gluon condensates together with an in-medium continuum threshold constrained by the light-quark condensate. By solving the resulting QCD sum rules, we determine the in-medium masses and leptonic decay constants of the $D_{s}^{*\pm}$ and $D^{*\pm}$ mesons over a broad region of the $(T, ρ)$ plane. Both vector mesons undergo substantial in-medium softening, with their masses and leptonic decay constants decreasing as the baryon density increases. The masses exhibit a non-monotonic dependence on baryon density, whereas the leptonic decay constants decrease monotonically throughout the investigated density range. Increasing temperature generally weakens the density-induced modifications, although baryon density remains the dominant driver of the in-medium evolution. The largest mass shifts occur at intermediate-to-high densities, reaching approximately $- 413 MeV$ for the $D_{s}^{*-}$ meson and $- 207 MeV$ for the $D^{*-}$ meson, while the leptonic decay constants are reduced by more than $68%$ in both channels at the highest densities considered. We further investigate the particle--antiparticle splittings of the masses and leptonic decay constants induced by finite baryon density. Finite baryon density lifts the vacuum degeneracy between the charge-conjugate states, while increasing temperature generally suppresses the resulting asymmetries. Although the strange and non-strange channels exhibit similar qualitative behavior, quantitative differences emerge in both the in-medium modifications and the particle--antiparticle splittings. ....
hep-phhep-exhep-lat0 citations
10
Direct versus resolved photons in DPS in photoproduction on proton and nuclei
B. Blok🇩🇪 · R. Segev🇩🇪
We study the process of double parton scattering (DPS) associated with the photoproduction at a future Electron-Ion collider (EIC) and HERA. We show that in the case of the resolved photon the 1 to 2 processes lead, even at small transverse momenta of the hard processes , to the increase of the DPS by a factor of order 1.6 in the significant part of the phase space, relative to the predictions of the mean field based models . Moreover we study the kinematic region where direct photon contribution is dominant and show it s boundaries for charm and light quark jets. For charmed jets we see that the relevant region is $x_{γ} \geq 0.2 - 0.4$ . This region is even enhanced if we consider the photoproduction on the nuclei.
hep-phhep-exnucl-exnucl-th1 citation
11
A Compact Phenomenological Pattern in Fermion Mass Ratios and Mixing Parameters
Petr Baron🇨🇿
We record a compact numerical regularity in charged-fermion mass ratios and fermion mixing parameters. The construction uses discrete generation labels G=1,2,3, fixed structural integers Nc=3 and Nw=2, sector exponent functions LA(G), and simple phase assignments. No continuous numerical optimization is performed: after one overall mass scale is chosen in each charged sector, the charged-fermion mass ratios and the leading mixing inputs follow directly from the stated formulae. The same exponent structure generates six charged-fermion mass ratios, six mixing sines, and the CKM phase as correlated numerical outputs. The full CKM and PMNS matrices are then obtained by standard unitary reconstruction. The construction is phenomenological and does not claim a first-principles derivation of the numerical constants.
hep-ph0 citations
12
Production of the top partner $T$ of the Bestest Little Higgs Model at the future muon collider
E. Cruz-Albaro🇲🇽 · D. Espinosa-Gómez🇲🇽 · A. Gutiérrez-Rodríguez🇲🇽 · F. Ramírez-Zavaleta🇲🇽 · E. S. Tututi🇲🇽 · A. M. Fernández-Figueroa🇲🇽
In this work, we evaluate the decay widths and branching ratios of the heavy top partner $T$ , and perform a comprehensive phenomenological study of its pair and associated production at a muon collider within the framework of the Bestest Little Higgs Model (BLHM). The BLHM provides an attractive and natural mechanism for addressing the fine-tuning problem in the Standard Model (SM) of particle physics. In our study of the top partner $T$ , we consider the production processes $μ^{+} μ^{-} \to (γ, Z, Z^{'}, h, H) \to T T ˉ$ and $μ^{+} μ^{-} \to (γ, Z, Z^{'}, h, H) \to t ˉ T + t T ˉ$ , and we explore different center-of-mass energies of the muon collider to perform our numerical analysis of the production cross sections for the processes of interest. Our results show that pair production is the most promising channel for probing the top partner of the BLHM at a future muon collider.
hep-ph0 citations
13
Probing the CP violation effects via the angular coefficients in Drell-Yan production
Qingyi Situ🇨🇳 · Bin Yan🇨🇳
The naive- $T$ -odd angular coefficients $A_{5}$ -- $A_{7}$ in Drell--Yan production are highly suppressed in the Standard Model (SM), making them sensitive probes of CP-violating interactions beyond the SM. We study these observables within the Standard Model Effective Field Theory (SMEFT), focusing on dimension-six electroweak and chromomagnetic quark dipole operators. Due to their chirality-flipping structure, the leading contributions from CP-violating dipole interactions arise at $O (1/ Λ^{4})$ through the interference between electroweak and chromomagnetic dipole amplitudes. We find that the sensitivity is primarily driven by $A_{6}$ and $A_{7}$ in the high dilepton transverse momentum region, where the dipole contributions are enhanced, while $A_{5}$ remains largely insensitive. Combining the ATLAS and CMS measurements, we constrain the CP-violating dipole combinations of Wilson coefficients at the $O (0.1)$ level for $Λ = 1 TeV$ . Assuming statistically dominated uncertainties at the HL-LHC, the sensitivity can be improved to the $O (1 0^{- 3})$ level. Our results highlight $A_{6}$ and $A_{7}$ as complementary probes of CP-violating dipole interactions at hadron colliders.
hep-phhep-ex0 citations
14
Holographic light quark jet quenching in flavor resolved QCD plasmas
Huwei Zhu🇨🇳 · Ke Ma🇨🇳 · Zi-qiang Zhang🇨🇳
We investigate light quark energy loss in a quark-gluon plasma using the holographic falling string setup. Stopping distances are computed from null geodesics in an Einstein-Maxwell-dilaton (EMD) background whose thermodynamics are lattice calibrated for three compositions: pure glue, two flavor QCD, and full QCD with strangeness. This geometry mirrors that of recent shooting string simulations, enabling a direct comparison between integrated stopping lengths and differential energy loss. Systematic scans over temperature, baryon chemical potential, and path length reveal that near the QCD crossover, plasmas with more dynamical flavors exhibit stronger quenching, consistent with RHIC strange hadron suppression data. At higher temperatures, approaching the conformal regime, this flavor hierarchy reverses, a trend absent in flavorless models. Finite baryon chemical potential shortens stopping distances and enhances energy loss, with marked sensitivity near the QCD critical endpoint, mirroring anomalies observed in RHIC beam energy scans. Consistent trends from these two independent holographic observables rule out formalism specific artifacts and support the reliability of our lattice calibrated EMD framework. We further discuss the geometric origin of the high temperature flavor ordering, parameter sensitivities, and possible extensions to heavy ion transport simulations.
hep-ph0 citations
15
A large size of the pion-like excitations in the stringy fluid above $T_{c h}$ is model independent and required by current algebra
L. Ya. Glozman🇦🇹
Multiple lattice evidences support the existence of a confining but chirally symmetric stringy fluid regime of QCD above the chiral symmetry restoration temperature at T_{ch} ~ 155 MeV. This regime is characterized by an approximate chiral spin symmetry and its extensions which means that the propagating excitations represent the chirally symmetric quarks connected into color singlets by the chromoelectric string. Clear \pi,\pi' peaks above T_{ch} were extracted on the lattice from the spatial and temporal correlators, which become broader with temperature and disappear roughly at $3 T_{c h}$ . The meson-like excitations above T_{ch} were studied within the manifestly confining and chirally symmetric model. It has been demonstrated that the chiral symmetry restoration in the confining regime happens because of Pauli blocking of the levels, required for the existence of the quark condensate, by the thermal quark excitation. The same Pauli blocking leads to a huge swelling of the low-spin mesons above T_{ch} which become infinitely large in the chiral limit. This property should be crucial for the explanation of the high collectivity and a very small mean-free path of the constituents above $T_{c h}$ seen experimentally. Here we demonstrate that the swelling of pions above T_{ch} is a model-independent effect required by current algebra.
hep-phhep-exhep-lathep-th+10 citations
16
Separating Equation-of-State Dynamics from Hadronic Rescattering in Low-Mass Dileptons
Apiwit Kittiratpattana🇹🇭 · Ayut Limphirat🇹🇭 · Yupeng Yan🇹🇭 · Christoph Herold🇹🇭
We investigate low-mass dilepton emission as a probe of the QCD equation of state and phase structure within non-equilibrium chiral fluid dynamics, comparing first-order phase-transition and crossover scenarios at $s_{NN} = 2.20 - 6.20$ ~GeV. To disentangle effects of the macroscopic equation-of-state dynamics from conventional hadronic in-medium modifications, the $ρ$ and $ω$ meson self-energies are calculated from the same resonance-driven forward-scattering amplitudes in both scenarios. We find two temporally distinct signatures of the first-order phase transition: an early enhancement in the vector-meson pole region associated with the non-equilibrium evolution through the phase transition, and a later enhancement of the low-mass continuum driven by reheating and the prolonged fireball evolution. Both effects survive integration over the complete space-time evolution, with the pole-mass region retaining the strongest sensitivity to the phase structure. Across the investigated beam energies, the pole-mass excitation function retains a pronounced sensitivity to first-order transition dynamics at low collision energies, identifying this mass region as a promising target for future dilepton beam-energy scans.
hep-phnucl-th0 citations
17
Improved covariant analysis of $B_{c}^{+} \to χ_{c 1} (n P)$ decays and implications for the nature of $χ_{c 1} (3872)$
Shi-Hang Zhang🇨🇳 · Jia-Yi Zheng🇨🇳 · Wei Li🇨🇳 · Su-Yan Pei🇨🇳 · Tianhong Wang🇨🇳 · Zhi-Hui Wang🇨🇳 · Chao-Hsi Chang🇨🇳 · Guo-Li Wang🇨🇳
We study the weak decays $B_{c}^{+} \to χ_{c 1} (n P) ℓ^{+} ν_{ℓ}$ and $B_{c}^{+} \to χ_{c 1} (n P) X$ (n=1,2,3) within the Bethe-Salpeter formalism, treating $χ_{c 1} (3872)$ as the conventional $χ_{c 1} (2 P)$ charmonium. We upgrade the covariant hadronic transition amplitude to consistently evaluate the final-state wave function in its rest frame, enabling a reliable description of large-recoil processes and sizable relativistic corrections pertinent to highly excited charmonium. Our results provide a novel platform to probe the internal structure of $χ_{c 1} (3872)$ via $B_{c}$ decays. While the LHCb search for $B_{c}^{+} \to χ_{c 1} (3872) π^{+}$ yielded only an upper limit, we demonstrate that this is primarily due to insufficient luminosity, approximately 20 times the current $B_{c}$ data sample would be required for a definitive observation. In contrast, we identify the semileptonic mode $B_{c}^{+} \to χ_{c 1} (3872) μ^{+} ν_{μ}$ as a far more promising channel, which could become accessible with merely twice the existing data set. Our predictions offer concrete guidance for upcoming LHCb analyses and complement ongoing efforts to resolve the nature of $χ_{c 1} (3872)$ .
hep-ph0 citations
18
Isochrone fitting of Galactic globular clusters - IX. Tip of the red-giant branch for 27 clusters and constraints on new particle physics
G.A. Gontcharov🇷🇺 · A.M. Kudashov🇷🇺 · O.S. Ryutina🇷🇺 · S.V. Troitsky🇷🇺
Red-giant evolution is sensitive to non-standard channels of energy loss in stellar cores and therefore provides a probe of new physics. Such losses increase the luminosity of the tip of the red-giant branch (TRGB), the brightest point reached by a red giant in the color-magnitude diagram. Previous analyses of TRGB luminosities in globular clusters placed stringent bounds on the axion-electron coupling g_ae, but were limited by observational and theoretical uncertainties. To improve these constraints, we use a new homogeneous set of parameters for 27 globular clusters, derived from our fitting of the Stetson ground-based, Hubble Space Telescope, and Gaia data by isochrones from the Dartmouth Stellar Evolution Database and a Bag of Stellar Tracks and Isochrones together with state-of-the-art Modules for Experiments in Stellar Astrophysics models. For each cluster, we identify the most luminous non-variable red giant, infer its luminosity from the best-fit isochrones, and apply Monte-Carlo based corrections for discrete sampling of the red-giant branch and for the exclusion of variable stars. We model the TRGB luminosity as a function of g_ae, as well as its uncertainties, for each cluster individually, and combine the results in a likelihood analysis. We find no indication of anomalous energy losses and obtain g_ae<3.8*10^(-14) at 95% confidence level. The median TRGB bolometric absolute magnitude is -3.53+-0.05 mag. We briefly discuss the implications for the neutrino magnetic dipole moment, millicharged particles, and other new physics.
hep-phastro-ph.GA0 citations
19
Thermal Alignment as a Pathway to Axion Dark Matter
Imtiaz Khan🇨🇳 · G. Mustafa🇨🇳 · Chengxun Yuan🇨🇳 · Farkhod Botirov🇺🇿 · Ahmadjon Abdujabbarov🇨🇳 · Farruh Atamurotov🇺🇿
Thermal alignment cannot be inferred from the axion mean alone because the dissipative bath that erases the initial displacement also prepares field and momentum fluctuations. We derive a phase space covariance bound that quantifies this memory and noise relation in the full inertial Langevin system. A renormalizable finite temperature gauge theory then links the temporary susceptibility, the Chern-Simons bath, bath termination, and the stable late potential through one scalar transition. Solving the coupled mean and covariance evolution demonstrates erasure of the incoming state, release of a causal infrared spectrum, and capture of the full phase space distribution as axion dark matter across the transition interval. Thermal alignment therefore determines a calculable late axion state rather than a homogeneous displacement alone.
hep-ph0 citations
20
CP Polarimetry with Linearly Polarized Photon Fusion and Double-Tagged Protons
Qi-Hui Chang · Shuai Zhao🇨🇳
Double forward-proton tagging turns the forward detectors into event-by-event photon polarimeters because each measured proton recoil fixes the transverse momentum, and hence the linear-polarization axis, of the emitted photon. We show that this production-side polarimetry gives a decay-analyzer-independent measurement of the CP phase of a photon-coupled spin-zero resonance. We derive the leading-power photon-density contraction for a CP-mixed hard amplitude with scalar and pseudoscalar couplings. The CP phase appears as a translation of the second harmonic in the signed proton--proton azimuthal angle. This provides a compact production-side CP measurement for axionlike particles and more general spin-zero resonances.
hep-phhep-ex0 citations
21
Generalized Glauber theorem for dark-matter axion and graviton detection
Jakub Bręczewski🇵🇱 · Ayuki Kamada🇵🇱 · Akira Miyazaki🇫🇷
We revisit the generalized Glauber theorem motivated by recent applications to dark-matter axion searches and graviton production. For Hamiltonian containing up to quadratic terms in annihilation and creation operators coupled to classical sources, the time-evolution operator can be factorized into displacement, squeezing, and rotation operators. We derive the differential equations governing time evolution of their parameters, reducing the quantum dynamics to c-number equations that can be solved analytically or numerically. To compare another form of the time-evolution operator, Dyson series, we demonstrate the essential role of time ordering. This formalism based on generalized Glauber theorem provides a unified description of particle production from classical backgrounds. Axion-photon conversion in microwave haloscopes is recovered as the linear-interaction limit, while squeezed graviton production from black-hole mergers follows naturally from quadratic interactions. Extending the theorem to thermal initial states yields a realistic quantum description of microwave cavities used in axion experiments. We show that higher-order photon statistics exhibit nontrivial behavior, providing a rigorous foundation for Monte Carlo simulations of quantum-enhanced axion searches beyond heuristic noise estimates.
hep-phgr-qchep-ex0 citations
22
High energy probes of Higgs self-coupling via $W$ boson fusion at future lepton colliders
Amir Subba🇨🇳 · Hrishikesh Deka🇮🇳 · Subhaditya Bhattacharya🇮🇳 · Abhik Sarkar🇮🇳
We investigate the sensitivity to the Higgs self-coupling through $W$ boson fusion di-Higgs production at CLIC with a center-of-mass energy of $s = 3$ TeV. We study the interplay between the Higgs self-coupling modifier ( $κ_{λ}$ ) and Higgs-gauge coupling modifiers ( $κ_{V}$ and $κ_{2 V}$ ) within the $κ$ framework. To enhance the separation between signal and background, we develop a graph neural network (GNN) based classifier that achieves a signal significance of $Z \approx 20 σ$ at $5 ab^{- 1}$ , substantially exceeding projected HL-LHC sensitivity. Our results demonstrate that high-energy lepton colliders, combined with graph-based machine learning, provide excellent sensitivity to the Higgs self-coupling and offer a powerful probe of new physics in the electroweak sector, disentangling linearly and non-linearly realized electroweak symmetry breaking.
hep-phhep-ex0 citations
23
The QCD Axion and Neutrino Masses
Hridoy Debnath🇺🇸 · Pavel Fileviez Perez🇺🇸 · Grace Miller🇺🇸
The strong CP problem and the origin of neutrino masses are among the clearest motivations for physics beyond the Standard Model. The Peccei-Quinn mechanism offers an elegant dynamical solution to the strong CP problem, predicting the QCD axion, while neutrino masses point to new degrees of freedom or interactions beyond the Standard Model. We explore the possibility that these two phenomena arise from a common origin by identifying the Peccei-Quinn symmetry-breaking scale with the scale responsible for neutrino mass generation. We perform a systematic and unified analysis of this connection in both DFSZ and KSVZ realizations of the Peccei-Quinn mechanism, considering the Type-I, Type-II, and Type-III seesaw mechanisms, the Zee radiative model, and the colored seesaw. For each scenario, we determine the axion couplings to photons and neutrinos and examine their phenomenological consequences. A robust prediction of all the frameworks considered is the existence of axion-neutrino couplings. We show that these interactions can significantly affect the axion decays. If the QCD axion makes up the observed dark matter, these couplings also lead to a large monochromatic neutrino flux from axion decays, opening a complementary path to test these theories in future neutrino experiments.
hep-phhep-ex0 citations
24
A Bayesian approach to the long-baseline neutrino oscillation sensitivity of DUNE
DUNE Collaboration: S. Abbaslu🇮🇷 · F. Abd Alrahman🇺🇸 · A. Abed Abud🇨🇭 · R. Acciarri🇨🇭 · M. A. Acero🇨🇴 · M. R. Adames🇧🇷 · G. Adamov🇬🇪 · M. Adamowski🇺🇸 · K. Adhikari🇬🇧 · C. Adriano🇧🇷 · K. Agudelo-Jaramillo🇨🇱 · F. Akbar🇺🇸 and 1274 other authors
The sensitivity of the Deep Underground Neutrino Experiment (DUNE) to neutrino oscillation is evaluated using a Bayesian Markov Chain Monte Carlo (MCMC) approach. This analysis uses the same underlying sensitivity inputs as previous DUNE studies [Eur. Phys. J. C 80, 978 (2020)], and therefore does not present updated DUNE sensitivities, but instead explores the additional inferences accessible using a Bayesian approach. We present four-dimensional posterior probability distributions of the oscillation parameters, highlighting the breadth of correlation in the parameter space of interest, especially between $sin^{2} θ_{23}$ and $sin^{2} θ_{13}$ . We exploit the flexibility of the Bayesian framework to incorporate parameter constraints post hoc and assess the impact of applying a reactor short-baseline $θ_{13}$ constraint. A significant increase in the sensitivity to the $θ_{23}$ octant is found when including the constraint. Posterior distributions of derived quantities can be easily constructed from MCMC results. This work presents the first study of DUNE's sensitivity to the Jarlskog invariant, $J$ , a quantity that provides a parametrisation-independent measure of charge-parity violation in the leptonic sector.
↳ hep-exhep-ph1 citation
25
Supersymmetry, Supergravity and the Consistency of On-Shell Massive Superamplitudes
Timothy Trott🇺🇸
I study constraints from consistent complex factorisation of $2 \to 2$ scattering amplitudes in $4 d$ and their relationship with supersymmetry. I complete the argument demonstrating that a massless helicity- $3/2$ particle must be a gravitino in a theory of supergravity and derive the structure and couplings of massive supermultiplets from first principles. For massive BPS particles in theories with extended supersymmetry, further constraints on the couplings are derived from consistent factorisation of massive superamplitudes. Among these is the requirement that BPS vector bosons must have couplings conforming to Lie algebra structure constants or generalised Chern-Simons terms. The gravitational coupling is shown to participate and draws the graviphotons into the Lie algebra. All $2 \to 2$ tree-level amplitudes of massive particles with spin $s \leq 1$ are calculated in (super)gravity using on-shell methods and the double copy. These are assembled and decomposed into (super)amplitudes with varying amounts of supersymmetry. Finally, I study scattering of BPS gravitinos with unbroken $N \geq 4$ supergravity and show that consistent factorisation leads to the full reconstruction of the super-Higgs mechanism. This argument completely determines the perturbative structure of all $N = 4$ Minkowski vacua of gauged maximal supergravity. Gravitinos in theories not admitting a super-Higgs mechanism are ruled-out.
↳ hep-thhep-ph2 citations
26
Cold Dark Matter and Self-Interacting Dark Matter Interpretations of Cloud-9
Morgan Ohana · Xingyu Zhang🇨🇳 · Hai-Bo Yu🇺🇸
Recently, the Five-hundred-meter Aperture Spherical Telescope discovered a gas-rich hydrogen cloud near M94 in the $21 cm$ band. Lacking an optical counterpart, this object, dubbed Cloud-9, has been identified as a compelling Reionization Limited \textsc{Hi} Cloud (RELHIC). RELHICs provide exceptionally clean laboratories for probing dark matter, free from the baryonic complexities associated with star formation and feedback. We show that the observed hydrogen column density profile of Cloud-9 is consistent with a gas cloud embedded in either a cuspy halo predicted by the standard cold dark matter (CDM) model or a cored halo produced by self-interacting dark matter (SIDM). In both cases, the halo must have an unusually diffuse central density. The best-fitting CDM halo lies around $7 σ$ below the cosmological concentration--mass relation, whereas SIDM core-forming halos reduce the tension to only around $3 σ$ . We further identify Cloud-9 analogs in the Concerto suite of cosmological zoom-in simulations with velocity-dependent SIDM, demonstrating that RELHICs provide a promising new probe of dark matter self-interactions.
↳ astro-ph.GAhep-ph0 citations
27
Directed Flow of Protons and Deuterons in Xe+Cs(I) Collisions: Preliminary BM@N Data and THESEUS Modeling
M. E. Kozhevnikova🇷🇺 · M. V. Mamaev🇷🇺 · I. A. Zhavoronkova🇷🇺 · A. V. Taranenko🇷🇺 · Yu. B. Ivanov🇷🇺
Preliminary BM@N results on the directed flow ( $v_{1}$ ) of protons and deuterons in Xe+Cs(I) collisions at 3.8 $A$ GeV are presented for the 10-40% centrality interval. The measured rapidity dependence of $v_{1}$ is compared with calculations from the THESEUS event generator, where deuterons are produced thermodynamically on an equal basis with hadrons using a late freeze-out scenario. While THESEUS well describes the proton $v_{1}$ data, it shows a slight but systematic overestimation of the deuteron flow at low and intermediate rapidities. This comparison tests both the collective dynamics of baryon-rich matter and the thermodynamic mechanism of light-nucleus formation at Nuclotron energies.
↳ nucl-exhep-phnucl-th0 citations
28
Population synthesis and detection prospects for Galactic long-period transients with LISA
Arthur G. Suvorov🇪🇸 · Nikolaos Karnesis · Valeriya Korol
The recently-discovered long-period radio transients represent a puzzling new class of astrophysical sources, some of which are thought to be compact binary systems emitting a pulse once per orbit. If this interpretation is correct, the orbital period--and therefore the gravitational-wave frequency--is directly encoded in the radio signal, which typically lies in the millihertz band. In this work, we explore whether these systems can be detected by the Laser Interferometer Space Antenna (LISA). Assuming that this phase-locking between radio pulses and orbital motion applies broadly across the population, we construct synthetic source catalogues informed by both observations and theoretical models of related systems, such as cataclysmic variables. We estimate that between $\sim 0.05%$ and $\sim 6%$ of long-period transients will be detectable within four years of observation with LISA, depending on astrophysical assumptions. For detectable systems, we find injected frequencies are recoverable to one part in $\sim 1 0^{5}$ , amplitudes to within a factor $\sim 2$ , and the sky positions to within $\sim$ 30 square degrees. Our results demonstrate that gravitational-wave observations can provide direct evidence for the binary nature of these sources and, importantly, can guide future radio surveys by predicting pulse periods, sky positions, and orbital properties. The mismatch between extracted frequency derivatives and that imposed by gravitational-wave decay is also computed to show that the likelihood of electromotive losses driving orbital evolution can be assessed for each detectable candidate.
↳ astro-ph.HEgr-qchep-ph0 citations
29
Magnetic catalysis and Hall conductivity of excitonic insulators in a planar four-Fermi model
William R. Tavares🇧🇷 · Rudnei O. Ramos🇧🇷 · Nei Lopes
We study the effects of a perpendicular magnetic field on the excitonic insulator (EI) phase in the semiconductor regime using an extended planar four-Fermi model. Within the large- $N$ approximation, we determine the coupled scalar and excitonic condensates at finite temperature, chemical potential, and magnetic field. The field enhances the EI condensate and raises its critical temperature, providing an excitonic realization of magnetic catalysis, while the scalar condensate remains constant throughout the EI phase. By contrast, the critical chemical potential depends nonmonotonically on the field because of the successive occupation of Landau levels. The magnetic field also shifts the mean-field tricritical point and enlarges the first-order region of the temperature--chemical-potential phase diagram. We further analyze the Hall conductivity and find that increasing the field reduces the number of plateaus and modifies the threshold for a finite Hall response. For the parameters considered, the emergence of the EI condensate is accompanied by a characteristic change in the Hall conductivity, including a field-dependent change of slope near a continuous transition. These results show that the combined phase structure and Hall response can provide complementary signatures of excitonic ordering in planar fermionic systems.
↳ cond-mat.mes-hallhep-ph0 citations
30
First Results on Nucleon Resonance Electroexcitation Amplitudes from $e p \to e^{'} π^{+} π^{-} p^{'}$ Cross Sections at $W$ from $1.56 - 1.76$ GeV and $Q^{2}$ from $2.0 - 5.0$ GeV $^{2}$
V.I.Mokeev🇺🇸 · P.Achenbach🇺🇸 · V.D.Burkert🇺🇸 · D.S.Carman🇺🇸 · R.W.Gothe🇺🇸 · E.L.Isupov🇷🇺 · K.Joo🇺🇸 · K.Neupane🇺🇸 · Y.Wunderlich🇺🇸
The first results on the electroexcitation amplitudes or the $γ_{v} p N^{*}$ electrocouplings for nucleon resonances ( $N^{*}$ s) in the third resonance region are presented. They were obtained from $π^{+} π^{-} p$ electroproduction differential cross sections measured with the CLAS detector and analyzed using the Jefferson Lab-Moscow State University (JM) reaction model. The analysis covers the invariant mass range of the final-state hadrons $W$ from 1.56 to 1.76~GeV and virtual photon four-momentum squared $Q^{2}$ from 2.0 to 5.0~GeV $^{2}$ . Consistent results on the electroexcitation amplitudes of the $N (1675) 5/ 2^{-}$ and $N (1680) 5/ 2^{+}$ obtained from independent analyses of both $π N$ and $π^{+} π^{-} p$ final states, demonstrate the capability of reaction models to extract the $γ_{v} p N^{*}$ electrocouplings for $N^{*}$ s in the third resonance region. Also, for the first time, the electrocouplings of the $Δ (1700) 3/ 2^{-}$ and $N (1720) 3/ 2^{+}$ , which predominantly decay into $π π N$ final states, have become available for $Q^{2} > 2.0$ ~GeV $^{2}$ . Finally, contributions from a new $N^{'} (1720) 3/ 2^{+}$ baryon state to the $π^{+} π^{-} p$ differential cross sections have been observed for $Q^{2} < 5.0$ ~GeV $^{2}$ . The new results on resonance electrocouplings in the third resonance region offer new opportunities to explore various aspects of the strong QCD regime responsible for the generation of nucleon excited states, in particular, shedding light on the emergence of hadron mass in connection with dynamical chiral symmetry breaking.
↳ nucl-exhep-phnucl-th0 citations
31
Post-Inflationary Constraints on Nonminimally Coupled Quintessential Inflation
Min Gi Park🇰🇷 · Seong Chan Park🇰🇷 · Tomo Takahashi🇯🇵 · José Jaime Terente Díaz🇵🇹
We investigate quintessential inflation in a nonminimally coupled scalar-tensor theory, parameterizing the post-inflationary radiation abundance independently of the reheating mechanism. The nonadiabatic inflation-kination transition generates a stochastic gravitational-wave background whose contribution to $Δ N_{eff}$ imposes a lower limit on the reheating temperature. Because this temperature dictates the duration of kination and the available scalar-field excursion, it directly constrains the present-day dark-energy equation of state. While a single-exponential coupling achieves the required post-inflationary potential drop, the same constant slope does not provide viable late-time acceleration. A double-exponential deformation resolves this tension by decoupling the average slope governing the total potential drop from the asymptotic slope driving cosmic acceleration. Full numerical solutions confirm this picture, yielding a thawing quintessence regime with $w_{φ, 0} ≃ (- 0.90, - 0.95)$ for our benchmarks. Our results demonstrate that future dark-energy measurements can directly probe the post-inflationary reheating history of the Universe.
↳ gr-qcastro-ph.COhep-ph0 citations
32
Constraining Lorentz invariance violation from the depth of air-shower maximum
Nickolay S. Martynenko🇷🇺 · Grigory I. Rubtsov🇷🇺 · Petr S. Satunin🇷🇺 · Andrey K. Sharofeev🇷🇺 · Sergey V. Troitsky🇷🇺
Hypothetical Lorentz invariance violation (LIV) remains strongly constrained but has not been excluded as a possible manifestation of new high-energy physics. In subluminal photon-sector LIV, suppressed Bethe $-$ Heitler pair production modifies the electromagnetic component of extensive air showers. We present a simulation-based toy analysis of this effect using published Pierre Auger fluorescence-detector distributions of the reconstructed depth of air-shower maximum. The modified distributions of the depth of the shower maximum are folded with the Auger detector-response parametrizations and compared with the data using free composition fractions in each reconstructed-energy bin. Within this approach, the comparison gives a sensitivity to LIV compatible with that expected from ultra-high-energy photon-induced showers. We obtain $M_{LIV} > 1.5 \times 1 0^{21} GeV$ ( $95%$ confidence level). This result should not be interpreted as a detector-level experimental limit because the detector response and reconstruction are simplified, and the result remains composition dependent. However, the approach presented here opens the way for constraining LIV in hadronic air showers with more detailed analyses.
↳ astro-ph.HEhep-ph0 citations

Affiliations

first authorsco-authorsvia INSPIRE