Mon·May 18, 2026Monday·May 18, 2026

1. 01*

   Predicting Three Generations of Fermions: Discovery Prospects of the Bilepton Model

   Andreas Crivellin🇪🇸 · Paul H. Frampton🇮🇹 · Ahmed Hammad🇯🇵

   We study the production of pairs of doubly-charged bileptons and assess their discovery potential in light of the integrated luminosities available at the High-Luminosity LHC. The production rates are governed primarily by the bilepton mass, $(m_Y)$, and the mass of the exotic heavy quarks, $(m_D)$. We consider two complementary production channels: (i) direct bilepton pair production and (ii) bilepton production mediated through heavy-quark decays. Notably, the latter typically yields significantly enhanced cross sections and gives rise to distinctive LHC signatures, even when the bileptons are produced off-shell. The two mechanisms therefore probe complementary regions of parameter space, with direct production being predominantly sensitive to $m_Y$, while the heavy-quark-mediated channel depends mainly on $m_D$. Owing to the essentially background-free signature of four energetic leptons at the LHC, we show that Run-2 data allow a discovery only for $m_D\lesssim 1\mathrm{TeV}$, whereas the HL-LHC can achieve a $5\sigma$ discovery up to $m_D\lesssim 2.5\mathrm{TeV}$ (nearly independently of $m_Y$) and/or for $m_Y\lesssim 2\mathrm{TeV}$ (even if $D$ is heavy).

   hep-phhep-ex0 citations
2. 02*

   Interactions of exotic neutralino dark matter with nucleons in $U(1)$ extensions of the MSSM originating from $E_6$ GUTs

   M. G. Belyakova🇷🇺 · R. B. Nevzorov🇷🇺

   To ensure anomaly cancellation the $E_6$ inspired $U(1)$ extensions of the minimal supersymmetric (SUSY) standard model (MSSM) involve extra exotic matter. The lightest exotic neutralino in these models can be stable contributing to the cold dark matter density. We consider the interactions of such neutralino with nucleons within a specific extension of the MSSM with an additional $U(1{)}_N$ gauge symmetry (SE${}_6$SSM). The constraints on the couplings of this state, which are set by the present experimental bounds caused by the direct detection experiments, are examined. The obtained results can be generalised to other $E_6$ inspired SUSY models with extra $U(1)$ gauge symmetry.

   hep-phhep-thNatural Sci.Rev.(2026)·0 citations
3. 03*

   Forward hadron production in pp collisions at LHC energies from an event generator based on the color glass condensate framework

   Hirotsugu Fujii🇯🇵 · Tetsufumi Hirano🇯🇵 · Kazunori Itakura🇯🇵 · Yasushi Nara🇯🇵 · Shujun Zhao🇯🇵

   We investigate inclusive forward single-hadron production in high-energy proton--proton collisions using a CGC-inspired Monte Carlo event generator, MC-CGC. We carried out a systematic study of the sensitivity of the running-coupling Balitsky-Kovchegov (rcBK) evolution equation to its initial conditions by comparing three parameterizations: the McLerran-Venugopalan (MV) model and its two HERA DIS-constrained variants, MV${}^{\gamma }$ and MV${}^e$. Our results indicate that the current LHCb data favor the MV${}^{\gamma }$ and MV${}^e$ models, while the differences from the original MV model become more pronounced at higher transverse momentum and at mid-rapidity. As a complementary analysis, we also compared the dilute-dense (DHJ factorization) and dense-dense ($k_T$ factorization) frameworks. We found that the $k_T$ factorization framework provides a better description of the particle production spectra at mid-rapidity than the DHJ framework, where both the projectile and target are in the dense regime at LHC energies. Predictions for the FoCal measurements at ALICE, including the production of identified neutral mesons and jets, are also presented.

   hep-phnucl-exnucl-th3 citations
4. 04*

   Precision studies of neutron decay, left-right asymmetry model of weak interaction, CP-violation and baryon asymmetry of the Universe

   A.P. Serebrov🇷🇺 · O.L. Fedin🇷🇺 · O.M. Zherebtsov🇷🇺 · A.K. Fomin🇷🇺 · R.M. Samoilov🇷🇺 · N.S. Budanov🇷🇺 · V.A. Kayaikin🇷🇺

   An analysis of the latest, most accurate experimental data on neutron decay points to the need to extend the Standard Model by introducing a right vector boson admixture $W_R$. A left-right asymmetry model of the weak interaction is presented, in which the sign of the mixing angle $W_R$ and $W_L$ is reversed upon transition from $W^{-}$ to $W^{+}$. In this model, CP violation occurs due to the presence of a right vector boson admixture. The model parameter, the mixing angle, $\zeta$=-(2.7$\pm$0.9)$\cdot$10${}^{-3}$ is derived from neutron decay - lifetime and decay asymmetries - as well as from studies of proton decay in nuclei, the so-called superallowed $0^{+}$-$0^{+}$ transitions. An estimate for the mass $W_R$ $M_{W_R}$=(340$\pm$60) GeV is given by the relation: from the parameter $\delta$=(5.5$\pm$1.8)$\cdot$10${}^{-2}$, which is the ratio of the squares of the mass states of vector bosons. The possibility of describing CP-violation effects in neutral meson oscillations within the left-right asymmetry weak interaction model with parameters $\delta$ and $\zeta$ is investigated. It is shown that within this model, CP violation effects in the decays of $K^0$-mesons, $D^0$-mesons, $B^0$-mesons, and $B_s^0$-mesons can be successfully described. Moreover, the sign of CP violation is opposite for particles and antiparticles, i.e., the CP violation phase is equal to $\pm \pi$/2, which corresponds to 100% CP violation. The results of calculations within the left-right asymmetry model with parameters $\delta$ and $\zeta$ are confirmed by experimental results with neutral mesons. The formation of baryon asymmetry in the Universe is considered in a left-right asymmetry model of weak interaction with an admixture of a right vector boson with different signs of the mixing angle with $W^{-}$ and $W^{+}$.

   hep-ph0 citations
5. 05*

   A Near-Cutoff Waveguide Haloscope for sub-meV Dark Matter

   Chuan-Yang Xing🇨🇳 · Bin Zhu🇨🇳

   We propose a near-cutoff parallel-plate waveguide haloscope for sub-meV dark matter. The concept retains the large-area openness of a dish antenna while providing cavity-like field enhancement through slow-wave response and coherent accumulation, without relying on a closed standing-wave resonance. For a copper waveguide, the projected dark photon sensitivity reaches $\epsilon \simeq 2.1\times 10^{-15}$ near $m_{A^{\prime }}\simeq 0.1\mathrm{meV}$. With an external magnetic field, the same transducer can approach QCD axion parameter space. The waveguide haloscope highlights a sensitive and scalable route toward future sub-meV bosonic dark matter searches.

   hep-ph1 citation
6. 06*

   Numerical Study of MRW-Type Unintegrated Double Parton Distribution Functions from Non-Factorized DPDFs

   R. Kord Valeshabadi🇮🇷 · S. Rezaie🇮🇷 · K. Azizi🇮🇷

   Double parton scattering provides a sensitive probe of multiparton correlations inside hadrons. In this work we present a numerical study of unintegrated double parton distribution functions constructed from non-factorized collinear DPDFs. As input we use the \texttt{GS09} DPDFs and evolve them to unequal scales with a numerical double DGLAP evolution framework, which is validated through the corresponding momentum and valence-number sum rules. We investigate MRW-inspired prescriptions for generating transverse momentum dependence in the double parton case. In particular, we study the double LO-MRW approach (DLO-MRW) in the perturbative region, the double modified KMRW approach (DMKMRW), the double virtuality ordered MRW (DVO-MRW) model, and a normalization-matched version of the latter. The DMKMRW, DVO-MRW, and matched DVO-MRW prescriptions can be applied directly to the full collinear DPDF, including its nonhomogeneous component, and avoid the piecewise treatment required in the conventional LO-MRW construction. We analyze the normalization, transverse momentum dependence, flavor dependence, and sensitivity to longitudinal DPDF correlations of the resulting distributions. The DMKMRW model is normalization preserving by construction, while the DVO-MRW model shows nontrivial normalization deviations that are removed in the matched version. Non-factorized effects are strongly channel-dependent. In DMKMRW, they enter mainly through longitudinal DPDF correlations, whereas in the LO-MRW and virtuality-ordered models, they also modify the transverse momentum shape. The largest deviations occur near the double parton kinematic boundary and in channels affected by valence-number and quark-antiquark correlations.

   hep-phhep-exhep-thEPJC(2026)·0 citations
7. 07*

   Geometric algebra as the input language of collider foundation models

   E. Abasov🇷🇺 · L. Dudko🇷🇺 · F. Grigoryev🇷🇺 · P. Volkov🇷🇺 · A. Zaborenko🇷🇺

   A hard hadron-collider event is represented here as a single geometric object: the kinematics and object-type labels of all reconstructed final-state particles in one multivector $\text{evMV}$, one $\text{Cl}(1,3)\otimes \text{Vflav}$ slot per object, whose higher grades the algebra generates from the measured four-momenta --- rather than as a list of four-momenta with label fields attached. The setting is geometric algebra, whose grade decomposition organises essentially every observable in current use: invariants at grade zero, four-momenta at grade one, decay-plane bivectors at grade two, oriented three-volumes at grade three, the CP-odd pseudoscalar at grade four. The high-level invariants, the low-level recipe and the equivariant-network inputs are recovered as projections onto specific grades. A per-grade dictionary of $32$ classical observables and an inventory of the symmetries acting on $\text{evMV}$ are provided. Theorem settles which Lorentz invariants the higher grades unlock: none beyond $\{p_i\cdot p_j,m_i^2\}$, the CP-odd sign of the pseudoscalar being the one genuine channel. The representation is intended as a uniform input layer for foundation models of collider physics, and the realisations demonstrated here occupy two rungs of a ladder: the higher grades are formed inside the network from the per-object slots, or selected grade-two and grade-three objects are supplied at the input layer. It is demonstrated on the resonance-topology separation of $pp\to tWb$ with a Lorentz-equivariant multivector transformer of L-GATr type. An ablation over eight input representations separates what supplying algebraic content explicitly can and cannot buy: content reconstructible from the measured momenta unlocks no new invariant, by the theorem, whereas a fixed reference blade encoding the beam plane carries structure the momenta do not contain.

   hep-ph0 citations
8. 08*

   One-Zero Neutrino Textures and Resonant Type-II Leptogenesis: Flavor-Resolved Thermal Evolution and Baryon Asymmetry

   Avinanda Chaudhuri🇮🇳

   We investigate the viability of one-zero neutrino mass textures within the framework of resonant Type-II leptogenesis. Considering a two-triplet scalar realization of the Type-II seesaw mechanism, we analyze the compatibility between neutrino texture structures, CP asymmetry generation, and the observed baryon asymmetry of the Universe. We perform extensive numerical scans over the neutrino parameter space and classify the phenomenologically viable one-zero textures under both hierarchical and resonant leptogenesis scenarios. We show that several one-zero textures remain compatible with neutrino oscillation data while simultaneously generating sizable CP asymmetries through resonant enhancement. We further investigate the thermal evolution of the generated asymmetry using Boltzmann equations and demonstrate the freeze-out behavior of the baryon asymmetry. Extending the analysis to a flavor-resolved framework, we study the separate evolution of electron, muon, and tau asymmetries and show that flavor-dependent washout effects play a crucial role in determining the final baryon asymmetry. Our analysis establishes a direct connection between neutrino flavor textures, resonant thermal leptogenesis, and flavor-dependent baryogenesis dynamics.

   hep-ph0 citations
9. 09*

   Inclusive charm and bottom quark pair production cross sections at hadron colliders at next-to-next-to-leading-order accuracy

   David d'Enterria🇨🇭 · Felix Hekhorn🇫🇮 · Ilkka Helenius🇫🇮 · Van Dung Le🇻🇳 · Hannu Paukkunen🇫🇮

   The inclusive cross sections for charm ($\mathrm{c}\overline{\mathrm{c}}$) and bottom ($\mathrm{b}\overline{\mathrm{b}}$) quark-antiquark pair production in proton-proton, proton-antiproton, and proton-nucleus collisions are studied over a wide range of center-of-mass energies, $\sqrt{s}\approx 10$ GeV--400 TeV. All existing data over $\sqrt{s}\approx 10$ GeV--14 TeV are collected and compared to calculations at next-to-next-to-leading-order (NNLO) accuracy using the new fixed-order MaunaKea open-source code for varying sets of parton distribution functions (PDFs). Relative to next-to-leading-order (NLO) predictions, the NNLO cross sections are enhanced by up to a factor of two, with the associated theoretical scale uncertainties reduced by the same amount, leading to agreement with experimental data over the full range of collision energies. The NNLO results are also compared with NLO predictions obtained within the SACOT-$m_{{}_{\mathrm{T}}}$ general-mass variable-flavour-number scheme. Despite still sizable theoretical and experimental uncertainties, $\mathrm{c}\overline{\mathrm{c}}$ cross section at multi-TeV energies can provide extra constraints on the gluon density at very small-$x$ in global PDF analyses. In the bottom sector, more precise cross section measurements at low energies, $\sqrt{s}\approx 10$--100 GeV, can help constraint the bottom-quark pole mass.

   hep-phhep-exnucl-exnucl-th1 citation
10. 10*

    The Monte Carlo Ecosystem in High-Energy Physics: A Primer

    Melissa van Beekveld🇳🇱 · Enrico Bothmann🇨🇭 · Andy Buckley🇬🇧 · Christian Gütschow🇬🇧 · Peter Skands🇦🇺 · Ramon Winterhalder🇮🇹

    Monte Carlo event generators are the central interface between theoretical calculations and experimental measurements in collider physics. Over several decades, a comprehensive and highly modular ecosystem of tools has developed around them, encompassing matrix-element calculations, parton showers, hadronisation models, and their integration with detector simulation, event-level analysis and statistical inference. While these tools are ubiquitous in modern research, the conceptual scope and technical structure of the full simulation chain can be challenging to navigate, particularly for researchers entering the field. In this primer, we provide a structured and up-to-date overview of the high-energy physics Monte Carlo ecosystem, focusing primarily on event-generator methodologies and their role within the broader collider workflow. We discuss the conceptual foundations of modern generators, the computational and organisational challenges of large-scale simulations, and the principles that enable interoperability and reproducibility across theory and experiment. We also examine the evolving computing landscape and sustainability considerations that will shape the future development of these tools. Aimed primarily at early-stage doctoral researchers while serving as a reference for the broader community, this article seeks to clarify architecture, methodology, and long-term trajectory of Monte Carlo event generation in collider physics.

    hep-ph3 citations
11. 11*

    Irreducible Graviton Floor from Reheating

    James M. Cline🇨🇦 · Yong Xu🇨🇦

    Inflaton decay inevitably emits gravitons through bremsstrahlung during reheating. We show that the soft part of this emission amplitude, fixed by Weinberg's soft-graviton theorem, becomes an irreducible stochastic gravitational-wave (GW) background after accounting for cosmological evolution. The theorem fixes the infrared branch of the spectrum, ${\Omega }_{\mathrm{GW}}\propto f$, independently of the microscopic operator responsible for inflaton decay, while the normalization is controlled by the hard inflaton decay rate and by a phase-space factor. We carry this out for inflaton $n$-body decays, including the phase-space integrals, finding that the maximum of the spectrum scales as $2/n$ relative to the $n=2$ case. The signal can reach ${\Omega }_{\mathrm{GW}}{h}^2\sim \mathcal{O}(10^{-17})$ at frequencies above the GHz scale. This predicts a stochastic graviton floor from perturbative reheating: a larger signal would require either other processes beyond perturbative bremsstrahlung or inflationary scenarios beyond conventional single-field slow roll.

    hep-phastro-ph.COhep-th4 citations
12. 12*

    Impact of spectator fields and non-minimal couplings in spontaneous baryogenesis

    Mattia Dubbini🇮🇹

    We investigate the model of spontaneous baryogenesis, considering two extensions to the background paradigm. Firstly, we introduce a non-minimal coupling between gravity and the inflaton, increasing the effective mass squared of the latter. In this way, the inflaton decays more likely into fermion-antifermion pairs during reheating, through baryon-number violating processes. Accordingly, we obtain an overall baryon asymmetry consistent with cosmological observations. Then, we consider a complex scalar spectator field interacting with the inflaton through a biquadratic coupling and non-minimally with gravity, and analyze the impact in terms of baryon asymmetry production. In this scenario too, the background model results significantly enhanced, but the predicted baryon-to-entropy ratio remains smaller than the experimental data.

    hep-phgr-qcInt. J. Mod. Phys. A (2026) 2646008·0 citations
13. 13*

    Scheme-invariant stratified factorization algebras for inclusive deep inelastic scattering

    Dustin Keller🇺🇸

    Inclusive deep inelastic scattering factorization combines two features that are often treated separately: an asymptotic reconstruction of the current-current matrix element from hard and long-distance data, and an invariance under finite changes of collinear scheme or operator basis. We formulate these two features as a single proof object. The construction packages the leading-region analysis, overlap subtraction, Wilson-line reduction, finite scheme kernels and physical measurement into a typed, filtered structure on a compactified space of asymptotic regimes. Its central carrier is the balanced hard-collinear core over the interface algebra of finite scheme transformations. The hard QCD input is the construction of a scheme-balanced comparison map from this core to the collinear collar of the regime algebra. Once this comparison is an equivalence through the chosen power accuracy and the measurement descends to convolution, the standard DIS convolution formula follows formally and independently of the chosen scheme presentation. We separate this formal implication from the analytic QCD obligations needed to construct the collar equivalence, describe Collins-style subtraction as descent and Möbius inversion on the region poset, and give a finite check relating $\overline{\mathrm{MS}}$ and DIS presentations. The framework is intended as proof infrastructure rather than as a new calculation of DIS coefficient functions. It supplies diagnostics for missing regions, nonclosed operator sectors, nonbalanced measurements and failed collar equivalences, and it gives a typed interface for future proof-assistant and machine-learning implementations of factorization workflows.

    hep-ph0 citations
14. 14*

    Freeze-in Warm Dark Matter via Dimension-6 Operators in 3-3-1 Models

    Fuwei Liu🇨🇳 · Fujun Liu

    We propose a natural resolution to the fine-tuning problem inherent in the freeze-in dark matter paradigm by embedding a sterile singlet within a 3-3-1 electroweak extension. By imposing an exact $Z_{13}$ discrete gauge symmetry, we formally suppress all low-dimensional portals to ensure that the dark sector communicates with the Standard Model (SM) exclusively through a dimension-six operator. This theoretical structure allows the extraordinarily small coupling required for dark matter production to emerge naturally from the profound hierarchy between the electroweak scale and the ultra-high Peccei-Quinn symmetry breaking scale. Detailed numerical integration of the Boltzmann equations demonstrates that the sterile singlet can be produced via the infrared freeze-in mechanism to match the observed relic abundance of ${\Omega }_S{h}^2=0.12$. The resulting keV-scale warm dark matter candidate remains consistent with stringent Lyman-alpha forest constraints while offering a viable solution to galactic-scale discrepancies such as the cusp-core and missing satellites problems. Ultimately, this framework provides a self-consistent unification of dark matter genesis and the strong CP solution that is completely independent of ad hoc parameter adjustments.

    hep-phastro-ph.COphysics.comp-ph0 citations
15. 15*

    Ultra high-energy cosmic rays from relativistic outflows in accretion induced collapse of white dwarfs

    Mainak Mukhopadhyay🇺🇸 · Shunsaku Horiuchi🇺🇸

    When a rapidly-rotating, highly magnetized white dwarf (WD) approaches the Chandrashekhar limit through mass accretion, it can undergo an accretion-induced collapse (AIC) to form a proto-neutron star or protomagnetar. The protomagnetar can drive a magnetically-dominated relativistic outflow, whose low entropy can lead to efficient formation of heavy nuclei. In this work, we propose that such relativistic outflows from AIC of WDs can contribute as sources of ultra high-energy cosmic rays (UHECRs). We model the acceleration of heavy nuclei in these relativistic outflows, and show that AICs can dominantly power the observed UHECRs, if a majority of them host relativistic outflows. Accounting for uncertainties in the acceleration mechanisms and AIC rates, AICs can contribute $\sim$ a few $10^{43}-10^{45}{\mathrm{erg}\mathrm{Mpc}}^{-3}{\mathrm{yr}}^{-1}$ in UHECR energy generation rate density, assuming iron-like nuclei.

    ↳ astro-ph.HEhep-ph0 citations
16. 16*

    Warm, not Fuzzy: Generalized Ultralight Dark Matter Limits from Milky Way Satellites

    Ethan O. Nadler🇺🇸 · Mustafa A. Amin🇺🇸 · Risa H. Wechsler🇺🇸 · M. Sten Delos🇺🇸 · Andrew Benson🇺🇸 · Vera Gluscevic🇺🇸

    We generalize lower limits on the dark matter (DM) particle mass $m$ derived from Milky Way (MW) satellite galaxy abundances to scenarios in which DM is an ultralight scalar field produced with a field power spectrum peaked at a subhorizon wavenumber $k_{\ast }$. In these models, the DM field free-streams similarly to warm DM while also exhibiting significant small-scale wave interference effects. The resulting dimensionless density power spectrum shows two effects: (i) free-streaming suppression at $k_{\mathrm{fs}}\sim k_{\mathrm{eq}}/[(k_{\ast }/a_{\mathrm{eq}}m)\ln (a_{\mathrm{eq}}m/k_{\ast })]$; (ii) Poisson-like enhancement related to wave interference at $k\gtrsim 10^{-2}{k}_{\ast }$, which saturates near the Jeans scale $k_{\mathrm{J}}\sim k_{\mathrm{eq}}/(k_{\ast }/a_{\mathrm{eq}}m)$. Comparing these predictions with established constraints on a free-streaming cutoff in the linear matter power spectrum from the MW satellite population and assuming that warm ultralight DM does not change the form of the galaxy--halo connection relative to cold DM, we obtain $m>6\times 10^{-18}\mathrm{eV}(k_{\ast }/10^4{\mathrm{Mpc}}^{-1})$ for $k_{\ast }>10^4{\mathrm{Mpc}}^{-1}$ at 95% confidence. For smaller $k_{\ast }$, Poisson-noise enhancement on MW satellite scales weakens the constraint, yielding $m>6\times 10^{-18}\mathrm{eV}(k_{\ast }/10^4{\mathrm{Mpc}}^{-1}{)}^2$ for $k_{\ast }<10^4{\mathrm{Mpc}}^{-1}$ at 95% confidence.

    ↳ astro-ph.COhep-phApJL(2026)·4 citations
17. 17*

    Pion emission source shape in UrQMD Au+Au collisions at STAR energies

    Matyas Molnar🇭🇺 · Daniel Kincses🇭🇺 · Mate Csanad🇭🇺

    Femtoscopic measurements of two-pion Bose--Einstein correlations have established that particle-emitting sources in heavy-ion collisions are well described by Lévy $\alpha$-stable distributions, motivating systematic studies across a wide range of collision energies. In this work, we present a three-dimensional femtoscopic analysis of pion pairs in Au+Au collisions simulated with the UrQMD model for collision energies $\sqrt{s_{NN}}=3$--$27\mathrm{GeV}$, taking the RHIC BES-II range of collider and fixed target experiment energies for reference. Using Lévy-type source parameterisations, we extract the pair multiplicity parameter ${\lambda }^{\ast }$ (related to the correlation strength $\lambda$), Lévy index $\alpha$, and three-dimensional radii $R_{\mathrm{out}}$, $R_{\mathrm{side}}$, and $R_{\mathrm{long}}$. We investigate their dependence on the transverse mass ($m_T$) and collision energy, along with derived quantities such as the radius difference $R_{\mathrm{diff}}^2=R_{\mathrm{out}}^2-R_{\mathrm{side}}^2$ and the ratio $R_{\mathrm{out}}/R_{\mathrm{side}}$. We find that $R_{\mathrm{out},\mathrm{side},\mathrm{long}}$ all decrease with increasing $m_T$ and increase with collision energy, consistent with collective expansion, $R_{\mathrm{long}}$ showing the strongest and $R_{\mathrm{side}}$ the weakest energy dependence. The Lévy index $\alpha$ decreases with collision energy, with a larger $m_T$-dependence towards higher energies. The ${\lambda }^{\ast }$ parameter is consistent with a constant close to unity in the absence of pions from long-lived resonances. These results provide a baseline for future comparisons with experimental measurements from the STAR Collaboration, contributing to constraints on the QCD phase diagram.

    ↳ nucl-thhep-phnucl-ex0 citations
18. 18*

    Average universal shower profile reconstruction using radio interferometry

    J. Alvarez-Muñiz🇪🇸 · W. R. Carvalho Jr.🇵🇱 · R. Conceição🇵🇹 · D. Dias🇵🇹

    Radio detection of extensive air showers enables near-continuous observation and precise measurements of the shower geometry and the depth of shower maximum, $X_{\max }$. Beyond $X_{\max }$, the longitudinal shower development follows a Universal Shower Profile (USP), whose shape parameters contain information on primary mass composition and hadronic interaction models. While previous studies have focused on event-by-event reconstruction of profile parameters, in this work we investigate the reconstruction of the average USP using radio interferometric techniques. Using Monte Carlo simulations, we reconstruct the average longitudinal profile directly from radio data and extract the Gaisser-Hillas shape parameters $(R,L)$. We find that the radio-derived average profiles provide enhanced separation between primary masses and hadronic interaction models compared to that obtained from fluorescence-equivalent longitudinal profiles. These results demonstrate that radio interferometry can access higher-order information on the longitudinal shower development and that the use of the average USP significantly improves the sensitivity to composition and hadronic interaction studies at ultra-high energies.

    ↳ astro-ph.HEhep-exhep-ph0 citations
19. 19*

    Accretion Effects on Primordial Black Hole Reheating Constraints

    Chenhuan Wang🇩🇪

    In this work, we study the effects of accretion on the primordial black hole (PBH) reheating scenario. PBHs could form from primordial fluctuations. If they have the right mass and abundance, they could dominate the Universe and complete the reheating entirely through Hawking radiation. We find accretion effects on the BH can not only increase the BH mass, but also prolong such early matter domination. The consequence of the accretion is further investigated using isocurvature induced gravitational waves (GWs), which are generated right after the sudden evaporation of the BHs from the oscillation of the gravitational potential. Big Bang nucleosynthesis limits on the energy density of the GWs put important constraints on the PBH domination scenario. Inclusion of accretion shifts such constraints significantly towards smaller formation mass and smaller initial abundance. Furthermore, the PBH could undergo mergers leading to extended mass functions. We find similar shifts in the allowed parameters with the inclusion of accretion for the merger constraint. We find the constraints from isocurvature GWs typically stronger than the constraints from mergers.

    ↳ astro-ph.COhep-ph2 citations
20. 20*

    Exact Bulk-Boundary Pairs in AdS/CFT

    Xin Jiang🇨🇳 · Peng Wang🇨🇳 · Haitang Yang🇨🇳

    We show that for a CFT${}_D$ on a flat open solid torus, the two point function in the Weyl frame is exactly paired with a finite geodesic lying entirely in the AdS${}_{D+1}$ bulk interior. This relation is exact and requires neither large $N$, strong coupling, nor heavy operators. The exactness is that of conformal kinematics; no semiclassical bulk dynamics is assumed. The standard boundary-anchored relation is a singular limit of the exact pair. For the free scalar, a mode expansion along $S^1$ generates an infinite tower of effective masses on $H_{D-1}$, whose intricate propagators resum exactly to the same simple higher-dimensional geodesic expression. Together with another exact pair between disjoint entanglement entropy and entanglement wedge cross-section found on the same open solid torus, this result points toward a broader exact-pair program in AdS/CFT.

    ↳ hep-thgr-qchep-ph3 citations
21. 21*

    Front propagation in non-homogeneous ${\varphi }^4$ model

    Jacek Gatlik🇵🇱 · Tomasz Dobrowolski🇵🇱 · Dominika Lasa🇵🇱 · Panayotis G. Kevrekidis🇺🇸

    We investigate the propagation of fronts in an inhomogeneous medium within the framework of the ${\varphi }^4$ model. The inhomogeneity is modeled either as an interface separating regions with different dissipation or as a finite layer with modified dissipation. The propagating front is described in two ways: as a kink solution in an effectively unbounded domain, and as a half-kink in a finite system. The half-kink represents the decay of the unstable state $\varphi =0$ toward the true vacuum. We show that while the effective description based on the kink provides accurate results, applying a similar approach to the half-kink leads to significant deviations from the predictions of the field model. We then demonstrate that a consistent description does exist and propose a modified effective model which reproduces the field-theory results over a relatively broad range of parameters.

    ↳ nlin.PShep-ph0 citations
22. 22*

    Anomalous Transport from Effective Field Theory

    Rémy Larue🇨🇳 · Amaury Marchon🇫🇷 · Jérémie Quevillon🇫🇷 · Diego Saviot🇫🇷

    A systematic study of chiral effects is presented using an Effective Field Theory framework. By integrating out a massive Dirac fermion at finite temperature in presence of vector and axial background fields, the currents and their anomalies are computed from the path-integral. Chiral effects previously considered separately naturally arise in a unified computation, including new mass corrections. The link between each anomalous transport effect and the anomalies is clearly established, beyond the identification of their coefficients. In particular, we can appreciate how these effects are sourced by the anomalous nature of the theory even in configurations where the anomaly itself vanishes. The consistent and covariant anomalies are both encapsulated in master formulae for the currents which result from a careful treatment of the regularisation. It is finally found that, at finite temperature, the physical currents cannot be inferred simply from the Chern-Simons terms whose divergence reproduce the chiral anomalies.

    ↳ hep-thcond-mat.stat-mechhep-ph0 citations
23. 23*

    Walking Sudakov: From Cusp to Octagon

    Luis F. Alday🇬🇧 · Elisabetta Armanini🇨🇭 · Andrei V. Belitsky🇺🇸 · Kelian Häring🇳🇱 · Alexander Zhiboedov🇨🇭

    We study the Sudakov form factor and the four-point scattering amplitude on the Coulomb branch of planar $\mathcal{N}=4$ SYM as functions of the Coulomb-branch parameters and kinematic invariants. This setup provides a controlled probe of the interpolation between on- and off-shell regimes of infrared-sensitive quantities in gauge theories. We identify a novel scaling limit in which both observables exhibit double-logarithmic behavior governed by a walking anomalous dimension. As the mass scales are varied, this walking anomalous dimension interpolates between the cusp anomalous dimension of the on-shell regime and the octagon anomalous dimension of the off-shell regime. Based on the explicit two-loop result and the expected all-order structure, we propose an all-loop form for the walking anomalous dimension both for the form factor and for the four-point scattering amplitude. These all-loop expressions depend on new, presently unknown functions of the 't Hooft coupling.

    ↳ hep-thhep-ph2 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.