Thu·Aug 7, 2025Thursday·August 7, 2025

1. 01*

   Indirect searches for realistic sub-GeV Dark Matter models

   Marco Cirelli🇫🇷 · Arpan Kar🇫🇷 · Halim Shaikh🇮🇳

   Indirect searches for Dark Matter (DM) particles with mass in the MeV -- GeV scale have received significant attention lately. Pair-annihilations of such DM particles in the Galaxy can give rise to (at the same time) MeV to GeV $\gamma$-rays via prompt emission, sub-GeV $e^{\pm }$ in cosmic-rays, as well as a broad photon spectrum ranging from $X$-rays to soft $\gamma$-rays, produced by the DM induced $e^{\pm }$ via inverse Compton scattering, bremsstrahlung and in-flight annihilation processes (collectively called `secondary emissions'). We focus on two representative realistic sub-GeV DM models, namely, the vector-portal kinetic-mixing model and the higgs-portal model, and perform a detailed study of the indirect detection constraints from existing $X$-rays, $\gamma$-rays and cosmic-ray observations, based on all of the above-mentioned signals. We also estimate the future prospects from the upcoming MeV photon telescope COSI, including all possible types of prompt and secondary emission signals. We compare our results with the constraints and (or) projections from cosmological and terrestrial observations. We find that, for both the sub-GeV DM models, the current observations constrain the annihilation cross-section at the level of $⟨\sigma v⟩\lesssim 10^{-27}{\mathrm{cm}}^3/\mathrm{s}$, or lower for some specific mass ranges or under optimistic assumptions. Moreover, new unconstrained DM parameter space can be probed at the upcoming instruments like COSI, thanks to the inclusion of secondary photons which in many cases provide the dominant signal.

   hep-phastro-ph.COastro-ph.GAJCAP(2026)·7 citations
2. 02*

   Flavour Physics Beyond the Standard Model

   Wolfgang Altmannshofer🇺🇸 · Peter Stangl🇨🇭

   Flavour physics plays a central role in the search for physics beyond the Standard Model, posing fundamental questions whose answers may point to new physics scales far above the electroweak scale. The flavour structure of the Standard Model is strikingly hierarchical, hinting at underlying organizing principles yet to be uncovered. At the same time, flavour-changing processes rank among the most sensitive probes of new physics. In this chapter, we review how precision measurements of flavour-violating observables, in particular meson-antimeson mixing and rare decays, provide powerful indirect tests of new physics, constraining scenarios from heavy mediators to light, weakly coupled particles. We also survey theoretical frameworks proposed to explain the origin of the Standard Model flavour hierarchies. Together, these complementary aspects demonstrate how flavour physics continues to shape both experimental strategies and theoretical developments in the quest to understand the fundamental structure of particle interactions.

   hep-phhep-ex9 citations
3. 03*

   Theory uncertainties in predictions of strong-field QED

   T. G. Blackburn🇸🇪

   Experiments using high-power lasers and relativistic electron beams will soon be capable of precision testing of the theory of strong-field quantum electrodynamics. The comparison between experiment and theory always occurs via numerical simulations, but the lack of quantitative uncertainty bounds for the latter means that the origin of any discrepancies cannot be identified conclusively. Here I present a simulation framework that can place meaningful bounds on the theory uncertainties inherent to its operation. This work shows that the use of the locally constant field approximation leads to a theory uncertainty of a few per cent in the signals of quantum radiation reaction expected in near-term experiments.

   hep-phphysics.plasm-phPRResearch(2026)·2 citations
4. 04*

   A background-free signal of jet-induced diffusion wake in quark-gluon plasma

   Zhong Yang🇺🇸 · Xin-Nian Wang🇨🇳

   Rapidity asymmetry of jet-hadron correlation has been proposed as a robust signal of dijet-induced diffusion wake in quark-gluon plasma in high-energy heavy-ion collisions. We generalize this observable to other jet configurations such as {\gamma}/Z0-jets and propose a new method to compute the rapidity asymmetry that is free of background. In this new method, the rapidity of the trigger is fixed or restricted to a symmetrical range while the rapidity of the associated jet is varied. The rapidity asymmetry is defined as the difference between the hadron rapidity distribution in the opposite azimuthal direction of the jet (or the same direction of the trigger) with different associated jet rapidities. Since the background in this hadron rapidity distribution with different associated jet rapidity is identical, it will be completely canceled in the rapidity asymmetry. Such background-free rapidity asymmetry caused by jet-induced diffusion wake is demonstrated in CoLBT-hydro simulations of dijets and {\gamma}-jets in Pb+Pb collisions at the LHC, which weakens as hadron pT increases, and subtraction of a p+p baseline has a negligible effect.

   hep-phnucl-thPRC(2026)·4 citations
5. 05*

   A neutrino data analysis of extra-dimensional theories with massive bulk fields

   Philipp Eller🇩🇪 · Manuel Ettengruber🇫🇷 · Alan Zander🇩🇪

   We present a global neutrino oscillation analysis of models with a single large extra dimension in which right-handed neutrinos possess bulk Dirac masses. Two scenarios are considered: Large Extra Dimensions with bulk masses and the Dark Dimension framework, both predicting a tower of sterile Kaluza-Klein states that mix with active neutrinos. Using data from MINOS/MINOS+, KamLAND, and Daya Bay, we perform a joint likelihood analysis. No signatures of these theories were found. Therefore, we constrain the compactification radius under different bulk mass and Yukawa coupling assumptions. Large positive bulk masses or sizable Yukawas lead to strong bounds, while small couplings or negative bulk masses remain less constrained.

   hep-phhep-exPRD(2025)·11 citations
6. 06*

   A New Source of Phase Transition Gravitational Waves: Heavy Particle Braking Across Bubble Walls

   Dayun Qiu🇨🇳 · Siyu Jiang🇨🇳 · Fa Peng Huang🇨🇳

   Motivated by the new heavy dark matter production mechanism from cosmic phase transition, we propose a novel mechanism for the generation of microscopic gravitational waves (GWs) during cosmological first-order phase transitions arising from the braking of heavy particles as they traverse bubble walls. Unlike the well-known sources such as bubble collisions, sound waves, or turbulence in the plasma, this mechanism originates from the direct interaction between massive particles and the expanding bubble wall. We use quantum field theory to rigorously compute the gravitational radiation. The resulting GW spectrum exhibits distinctive features: The peak frequency is tightly correlated with the bubble wall velocity, while the peak amplitude scales as the fourth power of the heavy particle mass. These unique dependencies offer a new observational handle on particle physics beyond the Standard Model. We illustrate this mechanism within a specific model framework and demonstrate its viability. Our findings enrich the landscape of phase transition GW sources and open new avenues for more directly probing heavy particle dynamics and new physics models in the early universe.

   hep-phJHEP(2026)·6 citations
7. 07*

   A comprehensive study of the charged Higgs boson in the two Higgs doublet type-II seesaw model

   Brahim Ait-Ouazghour🇲🇦 · Abdesslam Arhrib🇲🇦 · Mohamed Chabab🇲🇦 · Khalid Goure🇲🇦

   We investigate the phenomenology of the charged Higgs boson within the Two-Higgs-Doublet Type-II Seesaw Model (2HDMcT Type-III) at future ${\mu }^{+}{\mu }^{-}$ colliders. Focusing on $2\to 2$ processes such as ${\mu }^{+}{\mu }^{-}\to H_1^{+}{S}^{-}$ ($S^{-}=H_1^{-},H_2^{-}$) and ${\mu }^{+}{\mu }^{-}\to H_1^{+}{W}^{-}$, we incorporate both theoretical and experimental constraints to assess their production prospects. We find that $\sigma ({\mu }^{+}{\mu }^{-}\to H_1^{+}{H}_1^{-})$ can reach or exceed the corresponding $e^{+}{e}^{-}$ cross section, while $\sigma ({\mu }^{+}{\mu }^{-}\to H_1^{+}{H}_2^{-})$ is roughly eighteen times smaller but can be enhanced up to 0.62 fb upon relaxing electroweak precision observables constraints. Moreover, we observe that the cross section for ${\mu }^{+}{\mu }^{-}\to H_1^{+}{W}^{-}$ is significantly enhanced due to the large $\tan \beta$ amplification characteristic of the Type-III scenario. Furthermore, we conduct a signal-background analysis and determine the discovery ($5\sigma$) regions at a 3 TeV muon collider for the ${\mu }^{+}{\mu }^{-}\to H_1^{+}{H}_1^{-}$, ${\mu }^{+}{\mu }^{-}\to H_1^{+}{H}_2^{-}$, and ${\mu }^{+}{\mu }^{-}\to W^{\pm }{H}_1^{\mp }$ processes.

   hep-phhep-thPRD(2026)·6 citations
8. 08*

   Two-loop renormalisation of quark and gluon fields in the SMEFT in the on-shell scheme

   Claude Duhr🇩🇪 · Giuseppe Ventura🇬🇧 · Eleni Vryonidou🇬🇧

   We compute the contributions of CP-conserving dimension-six SMEFT operators to the two-loop renormalisation constants of quark and gluon fields in the on-shell scheme. Specifically, we consider the top-quark chromomagnetic operator and the triple gluon operator. We also compute the contribution of four-quark operators to the gluon renormalisation constant and discuss the implications for the running of the strong coupling constant.

   hep-phJHEP(2025)·17 citations
9. 09*

   Charged Higgs Signatures at Future Electron-Proton Colliders

   Baradhwaj Coleppa🇮🇳 · Gokul B. Krishna🇮🇳

   In this work, we present a detailed collider phenomenology study of the charged Higgs boson within a Beyond the Standard Model (BSM) framework featuring an extended gauge and scalar sector. The charged Higgs can decay via conventional modes, such as $H^{-}\to \bar{t}b$ and $H^{-}\to W^{-}h$, as well as through exotic channels like $H^{-}\to W^{\prime }Z$ (or $W{Z}^{\prime }$). These decays lead to distinct final-state topologies determined by the nature of the intermediate particles. We perform a comprehensive phenomenological analysis at future electron-proton colliders, namely the LHeC and FCC-eh, considering the luminosity projections provided in their design reports. Our results indicate that the conventional decay modes of the charged Higgs boson can achieve observable sensitivity and even discovery prospects at sufficiently high luminosities. In contrast, the exotic decay channel $H^{-}\to W^{\prime }Z$ does not exhibit any viable discovery potential. These findings highlight the complementarity of future electron-proton colliders in probing extended Higgs sectors, particularly through conventional charged Higgs signatures.

   hep-phEPJC(2026)·1 citation
10. 10*

    T versus CP effects in DUNE and T2HK

    Sabya Sachi Chatterjee🇩🇪 · Sudhanwa Patra🇮🇳 · Thomas Schwetz🇩🇪 · Kiran Sharma🇩🇪

    Time reversal (T) symmetry violations in neutrino oscillations imply the presence of an $L$-odd component in the transition probability at fixed neutrino energy, with $L$ denoting the distance between neutrino source and detector. Within the standard three-flavour framework, we show that the combination of the transition probabilities determined at the DUNE and T2HK experiments can establish the presence of an $L$-odd component, and therefore provide sensitivity to T violation, up to $4\sigma$ significance. The optimal neutrino energy window is from 0.68 to 0.92 GeV, and therefore a crucial role is played by the low-energy part of the DUNE event spectrum covering the second oscillation maximum. We compare the sensitivity to T violation based on this energy range using neutrino data only with the more traditional search for charge-parity (CP) violation based on the comparison of neutrino versus anti-neutrino beam data. We show that for DUNE it is advantageous to run in neutrino mode only, i.e., searching for T violating effects, whereas T2HK is more sensitive to CP violation, comparing neutrino and anti-neutrino data. Hence, the two experiments offer complementary methods to determine the complex phase in the PMNS mixing matrix.

    hep-phhep-exJHEP(2025)·1 citation
11. 11*

    Inelastically Decoupling Dark Matter

    Ronny Frumkin🇮🇱 · Yonit Hochberg🇮🇱 · Eric Kuflik🇮🇱 · Binyamin Vilk🇮🇱

    We present a new dark matter candidate, the `inELastically DEcoupling Relic' (iELDER), which is a cold thermal relic whose abundance is determined by the freeze out of its inelastic scattering off of bath particles in the presence of $3\to 2$ self-annihilations. The dark matter is predicted to be light, in the $O(\mathrm{MeV}-\mathrm{GeV})$ range, with significant self-annihilations and very weak inelastic couplings to ordinary matter. We demonstrate iELDER dark matter using a $Z_3$-symmetric toy model as well as QCD-like pion theories-the latter showing promising prospects for detection and providing a new benchmark for future searches.

    hep-phPRD(2026)·2 citations
12. 12*

    Scaling Relations for Dark Matter Halos Hosting Ultra-Faint Dwarf Galaxies

    Levi K. C. Fisher · Isabelle S. Goldstein · Jason Kumar🇺🇸 · Louis E. Strigari🇺🇸

    We consider the extraction of parameters of dark matter halos hosting ultra-faint dwarf galaxies, in the case where there are only $\mathcal{O}(10)$ identified member stars with measured line-of-sight velocities. This scenario is likely to be increasingly common, as upcoming newly discovered dwarf galaxies in the Milky Way, by e.g. the Rubin Observatory, will likely (at least initially) have only a few identified members. Assuming an NFW dark matter profile, equilibrium modeling likely can only robustly extract one halo parameter (${\rho }_s{r}_s$), but the scale radius itself will typically be unconstrained. In these cases, the results obtainable from Jeans modeling can be well replicated by a simple scaling relation motivated by the half-light mass estimator. As a application, we examine the recently discovered stellar system Ursa Major III, which has been optimistically assessed to have the largest $J$-factor of any known object. We suggest that, because of the presence of outlier stars, the $J$-factor obtained from modeling of Ursa Major III is likely inflated, as it is inconsistent with the half-light mass estimator, while removal of the outliers will leave the $J$-factor unconstrained from below.

    ↳ astro-ph.COastro-ph.GAhep-ph2 citations
13. 13*

    Graph theory-based automated quantum algorithm for efficient querying of acyclic and multiloop causal configurations

    Salvador A. Ochoa-Oregon🇪🇸 · Juan P. Uribe-Ramírez🇲🇽 · Roger J. Hernández-Pinto🇲🇽 · Selomit Ramírez-Uribe🇲🇽 · Germán Rodrigo🇪🇸

    Quantum algorithms provide a promising framework in high-energy physics, in particular, for unraveling the causal configurations of multiloop Feynman diagrams by identifying Feynman propagators with qubits, a challenge analogous to querying directed acyclic graphs in graph theory. In this paper, we present the Minimum Clique-optimised quantum Algorithm (MCA), an automated quantum algorithm designed to efficiently query the causal structures within the Loop-Tree Duality. The MCA quantum algorithm is optimised by exploiting graph theory techniques, specifically, by analogy with the Minimum Clique Partition problem. The evaluation of the MCA quantum algorithm is exhibited by analysing the transpiled quantum circuit depth and quantum circuit area.

    ↳ quant-phhep-phhep-thCommun.Phys.(2026)·6 citations
14. 14*

    Benchmarks and applications of the nuclear deexcitation event generator NucDeEx

    Seisho Abe🇯🇵

    Neutron multiplicity is a key observable in recent neutrino experiments that can enhance the sensitivity of various neutrino physics searches. Nuclear deexcitation plays a significant role in neutron emissions associated with neutrino-nucleus interactions. Therefore, precise prediction of this process is essential. To address this need, a general-purpose nuclear deexcitation event generator \textsc{NucDeEx} was developed and released as an open-source package. The treatment of low-lying discrete excited states was updated to better reproduce experimental data. Benchmarks were conducted using existing nuclear deexcitation event generators and experimental data. Application to other simulators, neutrino event generator \textsc{NEUT} and general particle simulation tool \textsc{Geant4}, are also presented.

    ↳ hep-exhep-phPRD(2025)·1 citation
15. 15*

    Gravitational wave spectra for cosmological phase transitions with non-linear decay of the fluid motion

    Isak Stomberg🇪🇸 · Alberto Roper Pol🇨🇭

    We summarize the theoretical framework of gravitational wave (GW) production by bulk fluid motion induced by expanding broken-phase bubbles during a first-order phase transition. Using a locally stationary unequal-time correlator (UETC) to model the decay of the source due to non-linearities, we provide templates for the resulting GW background that have been validated against data from Higgsless simulations. This UETC generalizes the stationary one considered in the sound-shell model, appropriate for linear sound waves whose kinetic-energy decay is negligible, to encompass the non-linear evolution of the compressional fluid motion beyond the sound-wave regime. We demonstrate the implementation of templates based on this theoretical description and the results from the Higgsless simulations in the public Python package CosmoGW, facilitating their use in experimental forecasts and parameter-estimation studies. The GW spectrum is delivered as a function of the key phase transition parameters: the wall velocity $v_w$, the strength $\alpha$, the nucleation rate $\beta$, and the source duration $\delta {\eta }_{\mathrm{fin}}$.

    ↳ gr-qchep-ph3 citations
16. 16*

    Effective Field Theory Constraints on Primordial Black Holes from the High-Redshift Lyman-$\alpha$ Forest

    Mikhail M. Ivanov🇺🇸 · Sokratis Trifinopoulos🇨🇭

    We present updated constraints on the abundance of primordial black holes (PBHs) dark matter from the high-redshift Lyman-$\alpha$ forest data from MIKE/HIRES experiments. Our analysis leverages an effective field theory (EFT) description of the 1D flux power spectrum, allowing us to analytically predict the Lyman-$\alpha$ fluctuations on quasi-linear scales from first principles. Our EFT-based likelihood enables robust inference across redshifts $z=4.2-5.4$ and down to scales of 100 kpc, within previously unexplored regions of parameter space for this dataset. We derive new bounds on the PBH fraction with respect to the total dark matter $f_{\text{PBH}}$, excluding populations with $f_{\text{PBH}}\gtrsim 10^{-3}$ for masses $M_{\text{PBH}}\sim 10^4-10^{16}{M}_{\odot }$. This offers the leading constraint for PBHs heavier than $10^9{M}_{\odot }$ and highlights the Lyman-$\alpha$ forest as a uniquely sensitive probe of new physics models that modify the structure formation history of our universe.

    ↳ astro-ph.COhep-phPRL(2026)·16 citations
17. 17*

    Mode-by-mode evolution of Pb-Pb collisions at 5.02 TeV in a hybrid model

    Renata Krupczak🇩🇪 · Nicolas Borghini🇩🇪 · Hendrik Roch🇺🇸

    We determine the average state and the uncorrelated modes that characterize the event-by-event fluctuations of the initial state in two typical centrality classes of Pb-Pb collisions at 5.02 TeV. We find that modes in a narrow central bin are similar to those in events at fixed vanishing impact parameter, while those in a mid-peripheral centrality class are affected by the impact-parameter variation. We study how each fluctuation mode affects observables both in the initial state and in the final state of the collisions, at the end of a state-of-the-art boost-invariant hybrid evolution with KoMPoST + MUSIC + iSS + SMASH, and show that implementing a hadronic transport cascade in such a mode-by-mode analysis with reasonable statistical noise is costly but feasible.

    ↳ nucl-thhep-phEPJC(2025)·1 citation

* 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.