Tue·Mar 24, 2026Tuesday·March 24, 2026

1. 01*

   Inverse Electroweak Baryogenesis

   Jacopo Azzola🇩🇪 · Oleksii Matsedonskyi🇩🇪 · Andreas Weiler🇩🇪

   We propose a mechanism for baryogenesis in which the baryon asymmetry is generated as an equilibrium response of weak sphalerons in a region where electroweak sphaleron transitions remain unsuppressed, $h/T\lesssim 1$. A nonzero equilibrium baryon density arises in the presence of an approximately conserved global charge, carried either by new states with nonzero hypercharge, or by Standard Model fields themselves. The required global charge asymmetry is generated during a phase transition that changes the strength of electroweak symmetry breaking, but need not coincide with the final electroweak phase transition. In particular, the mechanism can operate during an inverse electroweak phase transition, where baryon number is produced behind the advancing wall, in contrast to conventional electroweak baryogenesis. Because baryon production is decoupled from a direct first-order electroweak phase transition, the scenario can be realized at parametrically higher temperatures than standard electroweak baryogenesis, thereby weakening current experimental constraints. This framework provides a qualitatively distinct route to electroweak baryogenesis, with different parametric dependence, phase-transition dynamics, and phenomenological signatures.

   hep-phastro-ph.CO2 citations
2. 02*

   Probing the Higgs Self-Coupling with an XFEL Compton $\gamma \gamma$ Collider at $\sqrt{s}=380$ GeV

   Santiago Ampudia Castelazo🇺🇸 · Umar Sohail Qureshi🇺🇸 · Tim Barklow🇺🇸 · Ariel Schwartzman🇺🇸

   We present a study probing the Higgs self-coupling with the X-ray free-electron laser Compton $\gamma \gamma$ Collider (XCC) concept. The analysis is performed considering the $\gamma \gamma \to HH\to bb\overline{bb}$ channel, and results are then extrapolated to obtain a projection on the Higgs self-coupling sensitivity that ranges between 7% and 12%. An ensemble of boosted decision trees is trained to discriminate between signal and backgrounds, paired with a genetic algorithm optimizer to combine the final classifier outputs. This study suggests that an X-ray FEL-based $\gamma \gamma$ collider is a powerful tool to probe the mechanism of electroweak symmetry breaking, complementary to $e^{+}{e}^{-}$ Higgs factories and future high-energy hadron colliders.

   hep-phhep-exJHEP(2026)·5 citations
3. 03*

   Additional TeV-Scale Particles Predicted by Quartification

   Paul H. Frampton🇮🇹 · Thomas W. Kephart🇺🇸

   The LHC has failed to discover any new elementary particle since the Higgs boson completed the standard model in 2012, Here we adopt the attractive method of quiver gauge field theories to make predictions of additional particles which might be found at Run 4 of the upgraded LH-LHC scheduled to begin in 2030. We use an $SU(3{)}^4$ quiver gauge theory and exhaustively classify all possibilities according to how many of the added states shlep, meaning acquire a super-heavy Dirac mass. We arrive at four different choices, each of which suggests interesting positive outcomes for Run 4.

   hep-phhep-exhep-th0 citations
4. 04*

   Causality and stability analysis of relativistic spin hydrodynamics: Insights from a nonvanishing spin density background

   Wei Lu🇨🇳 · Yang Zhong🇨🇳 · Sheng-Qin Feng🇨🇳

   We investigate the stability and causality of relativistic spin hydrodynamics in the presence of a nonvanishing spin density background, assuming that the spin chemical potential ${\omega }^{\mu \nu }$ is of leading order (${\omega }^{\mu \nu }\sim \mathcal{O}(1)$) in the gradient expansion and is treated as a finite background in the linear perturbation analysis. It is found that within the first-order spin hydrodynamic framework, a finite spin density background modifies the dispersion relations, and modes propagating along different directions are controlled by distinct transport coefficients. Certain specific modes only appear in the $x$ direction. However, the modes in the large wave-vector limit exhibit acausal behavior. To address this issue, we subsequently adopt the framework of minimal causal spin hydrodynamics and derive the corresponding stability and causality conditions. The spin density background directly determines whether stability and causality can be satisfied simultaneously. In the small wave-vector limit, the results are similar to those of the first-order theory. In the large wave-vector region, however, significant differences emerge: the distinctions between different directions are no longer merely simple substitutions of transport coefficients, but involve more complex combinations. This indicates that the difference between modes in different directions increases with increasing wave vector.

   hep-phPRD(2026)·2 citations
5. 05*

   Reheating Effects on Charged Lepton Yukawa Equilibration and Leptogenesis

   Rishav Roshan

   We show that accounting for a non-instantaneous reheating phase after inflation can significantly modify the charged lepton Yukawa equilibration temperature in the early Universe. This finding calls for revisiting the role of lepton flavors in leptogenesis models where right-handed neutrinos are produced and decay during the extended reheating period. Our analysis reveals that this effect can induce shifts in the flavor regime(s) of leptogenesis relative to standard scenario.

   hep-phPoS(2026)·0 citations
6. 06*

   Searching for the Proton's Missing Spin: Small-$x$ Helicity Evolution Equations and Their Analytic Solutions

   Jeremy Borden🇺🇸

   The proton spin puzzle denotes the challenge of describing the proton's spin in terms of the angular momenta of the quarks and gluons which comprise it. These quarks and gluons carry a fraction $x$ of the proton's momentum. Contributions from small-$x$ quarks and gluons, which only possess a little of the proton's momentum, are difficult to measure, since this requires very high energy experiments. Furthermore, early theoretical work in the 1990s predicted substantial contributions to the proton spin from these small-$x$ particles. We need theoretical control over this corner of phase space in order to resolve the spin puzzle. In this dissertation, we build upon an existing framework for studying spin at small-$x$. Previously, several sets of small-$x$ evolution equations were derived in this formalism -- one in the large-$N_c$ limit and one in the large-$N_c\&N_f$ limit. Here $N_c$ and $N_f$ are the numbers of quark colors and flavors. These equations were numerically solved but no analytic solutions had been found. In this dissertation we detail the construction of such analytic solutions, first in the large-$N_c$ limit and then in the large-$N_c\&N_f$ limit, after deriving an important correction to the existing large-$N_c\&N_f$ equations due to the contributions of quark-to-gluon transition operators. From the solutions constructed here, we can predict the behavior of the quark and gluon helicity distributions at asymptotically small-$x$ (and large-$N_c$ or large-$N_c\&N_f$), both as a general power law and further as explicit analytic expressions in the asymptotic limit. Our solutions also allow us to predict all four polarized DGLAP anomalous dimensions in the same limits, yielding expressions exact to all orders in the strong coupling. The expansions of our predictions agree completely with the full extent of existing finite-order calculations, to three loops.

   hep-ph1 citation
7. 07*

   Elastic proton-proton and pion-proton scattering in holographic QCD

   A. Watanabe🇯🇵

   The elastic proton-proton and pion-proton scattering processes are investigated in the framework of holographic QCD. Considering the Pomeron and Reggeon exchange in the Regge regime, the total and differential cross sections are calculated. In the model setup, the Pomeron and Reggeon exchange are described by the Reggeized spin-2 glueball and vector meson propagator, respectively. For the differential cross sections, contributions of the Coulomb interaction are also taken into account. Adjustable parameters involved in the model are determined with the experimental data, and it is presented that the resulting cross sections are consistent with the data in a wide kinematic region.

   hep-phhep-exnucl-exnucl-th0 citations
8. 08*

   Thermal modification of $K_1(1270)\to {\pi }^{+}{\pi }^{-}{K}^{+}$ in a hot hadronic medium

   Seung-il Nam🇰🇷

   We study the thermal modification of the exclusive decay $K_1^{+}(1270)\to {\pi }^{+}{\pi }^{-}{K}^{+}$ in a hot hadronic medium. The decay amplitude is constructed from effective hadronic interactions dominated by the $\rho$- and $K^{\ast }$-pole contributions, which enables a Dalitz-level analysis of the three-body decay in medium. Thermal effects associated with partial chiral-symmetry restoration are incorporated through a phenomenological interpolation toward vector--axial-vector degeneracy near the chiral crossover. As the temperature increases, the reduction of the parent $K_1$ mass strongly compresses the available three-body phase space, leading to substantial deformation of the Dalitz distribution and invariant-mass spectra, as well as to a pronounced suppression of ${\Gamma }_{K_1\to {\pi }^{+}{\pi }^{-}{K}^{+}}(T)$. As a further step toward future experimental comparison, we introduce normalized shape observables that quantify the thermal evolution of the $K^{\ast }$-dominated $\pi K$ region, the upper-edge weight of the $\pi \pi$ spectrum, and the compactification of the Dalitz population. The dominant effect identified in the present framework is therefore kinematic: thermal phase-space reduction in the strange axial-vector channel. These results suggest that the exclusive $K_1(1270)$ channel may provide a useful qualitative probe of in-medium strange axial-vector dynamics near the pseudocritical region.

   hep-phPRC(2026)·1 citation
9. 09*

   Light-cone Distribution Amplitudes of Vector Mesons within the Self-Consistent Light-front Quark Model

   Xiao-Nan Li🇨🇳 · Shuai Xu🇨🇳 · Qin Chang🇨🇳

   In this paper, we investigate the twist-2 and twist-3 light-cone distribution amplitudes (LCDAs) of vector mesons within the self-consistent light-front quark model, and the $n$th Gegenbauer moment $a_n(\mu )$, $\xi$-moment $⟨{\xi }^n{⟩}^{\parallel (\perp )}$ and transverse moment $⟨{\mathbf{k}}_{\perp }^n{⟩}^{\parallel (\perp )}$ are also carried out. Adopting the parameter set fixed by confinements from the mesonic decay constants, we perform the numerical analysis and the results reveal several key insights: (i) The flavor symmetry breaking effects are more pronounced in the twist-3 LCDAs of vector mesons, which leads to the establishment of $a_1^{\perp }>a_1^{\parallel }$ and $⟨{\xi }^n{⟩}^{\perp }>⟨{\xi }^n{⟩}^{\parallel }$. This is consistent with previous findings in research for the LCDAs of pseudoscalar mesons. (ii) For vector mesons, the twist dependence decreases in the heavy quark limit which lead to ${\varphi }_2^{\parallel }(x)\simeq {\varphi }_3^{\perp }(x)$. For pseudoscalar and vector mesons composed of the same quark constituents, their LCDAs with the same twist exhibit similarity and gradually converge as the increasing of quark mass, i.e., ${\varphi }_2^A(x)\simeq {\varphi }_2^{\parallel }(x)$ and ${\varphi }_3^P(x)\simeq {\varphi }_3^{\perp }(x)$ in $m_q\to \infty$. In the heavy-quark limit within the self-consistent LFQM framework, we find an approximate correlated spin-twist independence pattern, with ${\varphi }_2^A(x)\simeq {\varphi }_2^{\parallel }(x)\approx {\varphi }_3^P(x)\simeq {\varphi }_3^{\perp }(x)$, resulting from the suppression of twist dependence and the approximate spin independence between pseudoscalar and vector mesons.

   hep-phPLB(2026)·1 citation
10. 10*

    Solving Functional Renormalization Group Equations with Neural Networks

    Yang-yang Tan🇨🇳 · Wei-jie Fu🇨🇳 · Lianyi He🇨🇳 · Lingxiao Wang🇯🇵

    We employ deep neural networks to represent the field derivative of the scale-dependent effective potential in the functional renormalization group (fRG) framework for nonperturbative quantum field theory. By embedding the fRG flow equations directly into the loss function, the network parameters are determined so as to provide a continuous and differentiable representation of the scale- and field-dependent effective potential without relying on precomputed training data. Focusing on the $O(N)$ scalar field theory within the local potential approximation at finite temperature, we demonstrate that this neural network representation accurately captures the renormalization group flow across symmetric, broken, and critical regimes. A key ingredient is a decomposition of the representation into an analytically known large-$N$ contribution and a learned finite-$N$ correction, which efficiently mitigates numerical stiffness associated with convexity restoration in the broken phase. The physics-driven solutions show excellent agreement with established finite-difference and discontinuous Galerkin methods. We further apply the same strategy to the Wilson--Fisher fixed-point equation in three dimensions, illustrating that neural network representations provide a unified framework for both scale-dependent flows and fixed-point problems. For fixed points, the large-field asymptotic form alone can replace the exact large-$N$ reference, while a composite small- and large-field ansatz further improves accuracy, extending the method to problems without an analytically solvable limit. Our results indicate that physics-driven deep learning offers a robust and flexible numerical tool for functional renormalization group studies.

    hep-phPRD(2026)·3 citations
11. 11*

    Leptogenesis in the littlest inverse seesaw model

    Yan Shao🇨🇳 · Zhen-hua Zhao🇨🇳 · Yi-Fei Duan🇨🇳

    The littlest inverse seesaw (LIS) model represents the first low-scale seesaw framework to successfully account for all six physical observables of the neutrino sector with merely two effective free parameters, making it highly worthy of in-depth investigation. In this work, we investigate realizations of leptogenesis in this framework. We consider two distinct scenarios. In the first, the two pseudo-Dirac sterile neutrino pairs are initially exactly degenerate and subsequently acquire small mass splittings via the RGE effects, enabling resonant leptogenesis to occur across different PD pairs and consequently enhancing leptogenesis. In the second, the two PD pairs feature a hierarchical mass spectrum, and leptogenesis proceeds via sterile neutrino oscillations through the ARS mechanism. We show that the observed baryon asymmetry can be successfully reproduced in sizable regions of the parameter space without introducing additional free parameters, demonstrating that the LIS framework provides a viable and predictive setting for low-scale leptogenesis.

    hep-phPLB(2026)·0 citations
12. 12*

    From seesaw over-suppression to trimaximal mixing: why $A_4$ is the minimal resolution of the $Z_3$ neutrino failure

    Navid Ardakanian

    We investigate whether the type-I seesaw mechanism can rescue the $Z_3$ Froggatt--Nielsen framework for neutrinos and find that it cannot. With right-handed Majorana masses carrying the $Z_3$ charge structure dictated by the Majorana bilinear -- where suppression powers follow $(q_i+q_j)\mathrm{mod}3$ -- the mass matrix contains an unsuppressed off-diagonal entry whose dominance in $M_R^{-1}$, combined with the hierarchical column texture of $M_D$, over-suppresses the two lightest neutrino masses to $\mathcal{O}({\epsilon }^3)$ while $m_3$ remains $\mathcal{O}(1)$. This pushes the solar-to-atmospheric mass ratio to a median $\Delta m_{21}^2/\Delta m_{31}^2\sim 4\times 10^{-11}$ -- eight orders of magnitude below the observed value of $0.030$. We prove this failure is universal across all six permutations of the charges $(2,1,0)$ and show analytically that the generic ratio scales as $\Delta m_{21}^2/\Delta m_{31}^2\sim \mathcal{O}({\epsilon }^6)\sim 10^{-11}$, with fewer than $0.01\%$ of parameter-space points exceeding ${\epsilon }^2\approx 2\times 10^{-4}$. The PMNS angles remain Haar-random, carrying no information from the expansion parameter. We then show that $A_4$, the alternating group of order 12, is the minimal discrete symmetry resolving both failures. Its triplet representation provides two independent vacuum parameters controlling the solar and atmospheric mass scales separately, while constraining the PMNS matrix to the trimaximal TM${}_1$ pattern. The TM${}_1$ solar sum rule predicts ${\sin }^2{\theta }_{12}=0.318$ ($1.2\sigma$ from NuFit 6.0, $1.0\sigma$ from JUNO), and the atmospheric sum rule yields a parameter-free $({\sin }^2{\theta }_{23},\cos \delta )$ correlation predicting $\delta \approx -71^{\circ }$, testable at DUNE and T2HK.

    hep-ph5 citations
13. 13*

    Hyperbolic form factors for Yukawa interactions, and applications to the Earth

    Pierre Fayet🇫🇷

    We define the hyperbolic form factor of a density distribution as its bilateral Laplace transform, related by duality or analytic continuation to its form factor. For a sphere it is given by $\Phi (x=kR)=⟨\cosh \vec{k}.\vec{r}⟩=⟨\sinh kr/kr⟩$, expanded as $\sum \frac{x^{2n}}{(2n+1)!}\frac{⟨r^{2n}⟩}{R^{2n}}$, and similarly for the form factor $⟨\sin kr/kr⟩$. It is also obtained from the bilateral Laplace transform of $2\pi r\rho (|r|)$, and enters in the determination of the outside Yukawa potential induced by a new charge for a mediator of mass $m=k=1/\lambda$. $\Phi (x)$ may be expressed as $\frac{3}{x^3}(x\cosh x-\sinh x)\bar{\rho }(x)/{\rho }_0$, where $\bar{\rho }(x)$ is an effective density decreasing, for $d\rho /dr<0$, from the average ${\rho }_0$ at small $x$, down to $\rho (R)$. An inversion formula allows one to recover $\rho (r)$ from an analytic continuation of $\Phi (x)$, as $\rho (r)={\rho }_0(2R/3\pi r)\int \Phi (ix)\sin (x\frac{r}{R})xdx$. $\Phi (x)$ for the Earth is essential to determine limits on a new force, as tested by MICROSCOPE, depending on the density distribution within the Earth. Quite remarkably, much simplified density profiles, such as $\rho ={\rho }_{0}2R/3r$ or $\rho ={\rho }_0(\frac{5}{4}-\frac{r}{R}+\frac{R}{3r})$, provide analytic expressions of $\Phi (x)$ and $\bar{\rho }(x)$ giving almost the same values as in a 5-shell model. $\Phi (x)=(\sinh \frac{x}{2}/\frac{x}{2}{)}^2$ is valid to within $\simeq 1\%$ up to $x=4$. $\Phi (x)=[7x^2\cosh x-24\cosh x+9x\sinh x-4x^2+24]/(4x^4)$ is valid to within 1 % for $\lambda >$ 100 km (or $m<2\times 10^{-12}$ eV/$c^2$). For $m=10^{-12}$ eV/$c^2$ the coupling limits are increased by 34 as compared to a massless mediator, to $|g_{B-L}|<3.6\times 10^{-24}$ and $|g_B|<2.6\times 10^{-23}$ for a spin-1 mediator, with slightly different limits in the spin-0 case.

    hep-phhep-ex0 citations
14. 14*

    B-jet Tagging Using a Hybrid Edge Convolution and Transformer Architecture

    Diego F. Vasquez Plaza🇺🇸 · Vidya Manian🇺🇸

    Jet flavor tagging plays an important role in precise Standard Model measurement enabling the extraction of mass dependence in jet-quark interaction and quark-gluon plasma (QGP) interactions. They also enable inferring the nature of particles produced in high-energy particle collisions that contain heavy quarks. The classification of bottom jets is vital for exploring new Physics scenarios in proton-proton collisions. In this research, we present a hybrid deep learning architecture that integrates edge convolutions with transformer self-attention mechanisms, into one single architecture called the Edge Convolution Transformer (ECT) model for bottom-quark jet tagging. ECT processes track-level features (impact parameters, momentum, and their significances) alongside jet-level observables (vertex information and kinematics) to achieve state-of-the-art performance. The study utilizes the ATLAS simulation dataset. We demonstrate that ECT achieves 0.9333 AUC for b-jet versus combined charm and light jet discrimination, surpassing ParticleNet (0.8904 AUC) and the pure transformer baseline (0.9216 AUC). The model maintains inference latency below 0.060 ms per jet on modern GPUs, meeting the stringent requirements for real-time event selection at the LHC. Our results demonstrate that hybrid architectures combining local and global features offer superior performance for challenging jet classification tasks. The proposed architecture achieves good results in b-jet tagging, particularly excelling in charm jet rejection (the most challenging task), while maintaining competitive light-jet discrimination comparable to pure transformer models.

    hep-phcs.AIeess.SPJINST(2026)·0 citations
15. 15*

    Sequential retuning of PYTHIA~8.316 to a global soft-QCD basis in pp collisions at $\text{sqrts}=0.9-13$ TeV

    Haifa I. Alrebdi🇸🇦 · Muhammad Ajaz🇵🇰

    We present a sequential nine-parameter retune of PYTHIA 8.316, built on the Monash 2013 baseline, for soft-QCD observables in proton--proton collisions at $\sqrt{s}=0.9$--$13$ TeV. The tune is constructed with direct generator evaluation and developed in stages: an initial five-parameter localization in the hadronization-sensitive sector, successive extensions driven by multi-energy minimum-bias tensions, and a final expansion to a broader soft-QCD fit basis. The fitted set includes minimum-bias charged-particle data, identified-hadron spectra and ratios, underlying-event observables, and event-shape distributions. A separate held-out validation basis is kept outside the fit. The final tune retunes nine non-perturbative parameters controlling fragmentation, strangeness suppression, diquark production, color reconnection, MPI regularization and its energy dependence, the impact-parameter overlap profile, and transverse-momentum generation in string breaking. On the common fit basis, the grouped score density improves from $99.18$ for Monash 2013 to $85.67$. The strongest gains occur in the 13 TeV minimum-bias and underlying-event sectors, with further improvement in the ALICE identified-hadron blocks and a smaller gain in the CMS 13 TeV identified-hadron sector. Monash remains better in the CMS 7 TeV underlying-event block and the ATLAS 7 TeV event-shape block, while the low-energy charged-particle sector remains the main unresolved tension for both tunes. The held-out validation basis supports the same picture. Monash remains slightly better in the low-energy CMS validation blocks, but the present tune performs better in the ATLAS early underlying-event block and in both held-out 13 TeV charged-particle sectors. We interpret it as a controlled soft-QCD retune that improves a broad set of observables while keeping its limitations explicit.

    hep-ph3 citations
16. 16*

    From Higgs physics to lepton flavour violation: current bounds and future prospects for vector-like lepton models

    Gregor Daberstiel🇩🇪 · Kilian Möhling🇩🇪 · Dominik Stöckinger🇩🇪 · Hyejung Stöckinger-Kim🇩🇪

    We present a comprehensive phenomenological study of a class of six vector-like lepton models with seesaw-like mass contributions and strong modifications to Higgs and lepton phenomenology. We focus on lepton flavour conserving and violating observables across all lepton generations and collider observables like $Z$ and Higgs decays. In light of the recent progress at the LHC and precision measurements such as muon $g-2$, as well as in anticipation of upcoming experiments like MEGII, Mu2e/COMET, Mu3e, Belle II and at the HL-LHC, we systematically survey the viable parameter space and identify patterns and correlations. The considered class of models gives rise to a rich and testable phenomenology with robust and complementary probes that allow to distinguish between models in the coming experimental era.

    hep-phJHEP(2026)·1 citation
17. 17*

    CP-violation and its implications in a complex singlet extension of 2HDM

    Jayita Lahiri🇩🇪 · Gudrid Moortgat-Pick🇩🇪

    We investigate CP-violation in the complex singlet extension of the general Two Higgs Doublet Model (2HDM) with Yukawa alignment condition. We first explore the possibility of explicit CP-violation in the extended scalar sector while the 125 GeV Higgs remains exactly Standard Model (SM)-like. We identify an additional source of CP violation in the complex singlet extension compared to the 2HDM, which allows this model a substantially greater freedom in satisfying the stringent EDM constraints. We also incorporate dark matter in this model and investigate the impacts of constraints from the dark sector on the model parameter space and its interplay with CP-violation phases. We further explore the possibility of detecting such a scenario at future collider experiments via CP-violating trilinear couplings among the non-standard scalars. Finally, we also deviate from the exact alignment limit and investigate the CP-properties of the observed Higgs boson in the context of our model. We demonstrate the strong model-dependent nature of the detection prospects of the CP-phase of the Higgs boson at future experiments, exploring both fermion couplings as well as the trilinear self-coupling of the Higgs boson.

    hep-ph0 citations
18. 18*

    Recoil corrections to pentaquark molecules with an SU(3) anti-triplet heavy baryon

    Xiao Chen🇨🇳 · Li Ma🇨🇳

    Recoil corrections, which appear at order $\mathcal{O}(\frac{1}{M})$, turn out to be crucial for the pentaquark molecules with heavy flavor. In the past, such corrections were typically regarded as negligible for the formation of heavy molecules. However, our research manifests the important impacts on the spectra of possible baryon-meson bound states. In certain cases, the binding energy sharply decreases after considering the recoil corrections. Using the one-boson-exchange (OBE) model, we have studied a series of double heavy and hidden heavy pentaquark states with an SU(3) anti-triplet baryon, including ${\Xi }_c{\bar{D}}^{(\ast )}$, ${\Lambda }_c{\bar{D}}^{(\ast )}$, ${\Xi }_c{D}^{(\ast )}$, ${\Lambda }_c{D}^{(\ast )}$, along with their bottom analogues. Considering both the $S$\--{}$D$ wave mixing effect and the recoil corrections, we find that recoil corrections, working against the stability of bound states in certain isospin-singlet channels, which cannot be ignored. For the ${\Xi }_c\bar{D}$ and ${\Xi }_{c}D$ systems with $I(J^P)=0({\frac{1}{2}}^{-})$, the ${\Xi }_c{\bar{D}}^{\ast }$ and ${\Xi }_c{D}^{\ast }$ systems, as well as their bottom counterparts, with $I(J^P)=0({\frac{1}{2}}^{-})$ and $0({\frac{3}{2}}^{-})$, and the ${\Lambda }_b{\bar{B}}^{\ast }$ system with $I(J^P)=\frac{1}{2}({\frac{1}{2}}^{-})$ and $\frac{1}{2}({\frac{3}{2}}^{-})$, although the bound state solution can be found both with and without considering the recoil corrections, the inclusion of recoil corrections weakens the attraction of the molecules. This phenomenon arising from recoil corrections is especially prominent in the ${\Xi }_c{\bar{D}}^{\ast }$ and ${\Xi }_c{D}^{\ast }$ systems.

    hep-phhep-exhep-thPRD(2026)·1 citation
19. 19*

    Conditional Wasserstein GAN for Simulating Neutrino Event Summaries using Incident Energy of Electron Neutrinos

    Dipthi S. · Kalyani Desikan

    Event simulation for electron neutrino interactions plays a foundational role in precision measurements in particle physics experiments, yet the computational demand of traditional Monte Carlo methods remains a significant challenge, especially for complete, high-dimensional event reconstruction. In this study, we present a generative model based on the Conditional Wasserstein Generative Adversarial Network (CW-GAN) framework. This architecture is conditioned on the input neutrino energy. It utilizes a Wasserstein loss function, stabilized by a gradient penalty, to learn the complex mapping from a latent space to structured kinematic data. Our model is tailored to replicate the full multidimensional kinematics of electron neutrino interactions as described by the GENIE event generator. Our focus is specifically on the Inverse Beta Decay (IBD-CC), Neutral Current (NC), and nue-e-elastic scattering processes (NuEElastic), spanning an energy window of 10-31 MeV. Our approach abandons variable reduction schemes and instead generates the entire summary ntuple, enabling holistic event-by-event modeling. Training is performed separately for each of the three interaction types, with rigorous convergence monitoring over 100-300 epochs per channel. We perform a rigorous quantitative validation against held-out GENIE test datasets. The generated samples demonstrate fidelity, reproducing the 1D marginal distributions for all kinematic variables with statistical compatibility, and successfully capturing the complex non-linear correlations between them. This work offers a scalable and efficient alternative to traditional MC event generation, providing full-spectrum kinematic simulation for key electron neutrino interaction channels while drastically reducing computational overhead.

    hep-ph0 citations
20. 20*

    Isospin-breaking effects of the double-charm molecular pentaquarks

    Fei-Yu Chen🇨🇳 · Ning Li🇨🇳 · Wei Chen🇨🇳

    We investigate isospin-breaking effects in double-charm molecular pentaquarks with the $D^{(\ast )}{\Sigma }_c^{(\ast )}$ configuration, using the one-boson-exchange potential framework. In these systems, the isospin-breaking effects arise from two sources: the strong interaction, which manifests as the threshold difference of the $D^{(\ast )}{\Sigma }_c^{(\ast )}$ components in the same isospin multiplet and the mass splittings of the exchanged isovector mesons ($\pi$ and $\rho$); and the electromagnetic interaction between charged $D^{(\ast )}$ and ${\Sigma }_c^{(\ast )}$ components. We calculate the binding properties and the isospin mixing angle between the $I=1/2$ and $I=3/2$ states of the $D^{(\ast )}{\Sigma }_c^{(\ast )}$ system. Our results show that the isospin-breaking effect contributes a significant correction of roughly $10\%-30\%$ to the binding energy. This effect is particularly pronounced in loosely bound molecular candidates, which are characterized by small binding energies and large root-mean-square radii. We therefore conclude that the explicit inclusion of isospin-breaking effects is essential for achieving the precision in theoretical calculations necessary to match rapidly advancing experimental programs. Our results are expected to provide valuable guidance for future high-precision experimental studies of deuteron-like molecular states.

    hep-phhep-exPRD(2026)·0 citations
21. 21*

    Strong decays of the hidden-charm molecular pentaquarks

    Jin-Cheng Deng🇨🇳 · Yong Ru🇨🇳 · Xin-Yue Wan🇨🇳 · Tai-Fu Feng🇨🇳 · Bo Wang🇨🇳

    We investigate the strong decays of the recently observed hidden-charm pentaquarks \(P_{\psi}^N(4312)\), \(P_{\psi}^N(4440)\), and \(P_{\psi}^N(4457)\), as well as \(P_{\psi s}^\Lambda(4338)\) and \(P_{\psi s}^\Lambda(4459)\), within the molecular framework using the effective Lagrangian approach. We construct the effective Lagrangians describing the S-wave couplings between these pentaquarks and their constituent hadrons, namely \(\Sigma_c\bar{D}^{(*)}\) and \(\Xi_c\bar{D}^{(*)}\), and determine the coupling constants via the residues of the scattering \(T\)-matrix at the bound-state poles. Our results show that the decay widths are sensitive to the cutoff parameters in the form factors, whereas the branching fractions exhibit only weak dependence. Using \(P_{\psi}^N(4312)\) to calibrate the cutoff range, we further explore the spin assignments of \(P_{\psi}^N(4440)\) and \(P_{\psi}^N(4457)\). Our calculations favor the assignment where the lower-mass state \(P_{\psi}^N(4440)\) carries higher spin \(J = 3/2\) and the higher-mass state \(P_{\psi}^N(4457)\) carries lower spin \(J = 1/2\). In addition, the experimental widths of \(P_{\psi s}^\Lambda(4338)\) and \(P_{\psi s}^\Lambda(4459)\) can both be well reproduced under the molecular interpretation. We look forward to future experimental analyses with more accumulated data to clarify whether the lineshape of \(P_{\psi s}^\Lambda(4459)\) contains contributions from both spin-\(1/2\) and spin-\(3/2\) states.

    hep-phPRD(2026)·1 citation
22. 22*

    Comparing EPOS-4, EPOS-LHC, and SMASH for identified-hadron observables in the NICA energy range

    Murad Badshah🇵🇰 · Haifa I. Alrebdi🇸🇦 · Sana Raza Khan🇵🇰 · Muhammad Ajaz🇵🇰

    We present a systematic simulation study of identified hadron production in minimum bias Au+Au collisions at sqrt(sNN) = 6, 7, and 8 GeV. The event samples were generated with three modern frameworks based on different microscopic pictures: EPOS-LHC, EPOS-4, and the purely hadronic transport model SMASH. We compare observables that probe baryon stopping, transverse dynamics, hadron formation, and strangeness production: rapidity densities dN/dy, transverse momentum spectra dN/dpT, two dimensional pT-y distributions, v2/nq versus pT/nq, and the yield ratios pi-/pi+, K-/K+, pbar/p, K+/pi+, K-/pi-, p/pi+, and Lambda/pi+. For charged and neutral pions, the three models give broadly similar yields and spectral shapes in both dN/dy and dN/dpT. At these energies, resonance decays and isospin constraints reduce the sensitivity to early stage dynamics. In contrast, strange mesons and baryons remain strongly model dependent. EPOS-4 gives the largest midrapidity K+ and Lambda yields and the hardest kaon and strange baryon pT spectra. EPOS-LHC is generally intermediate, while SMASH gives lower strange hadron production. The two dimensional pT-y maps show that the EPOS models populate higher pT over a broader rapidity range. For NCQ scaled elliptic flow, the best approximate scaling is seen in EPOS-LHC, while SMASH and EPOS-4 show only partial scaling. This suggests that EPOS-LHC carries a more coherent partonic anisotropy to the hadronic stage in this energy range. Overall, the model separation grows from 6 to 8 GeV. The clearest discriminators in the NICA domain are intermediate pT baryon to meson ratios, Lambda/pi+, the rapidity dependence of pT, the pT dependence of K-/K+, and NCQ scaled v2.

    hep-ph0 citations
23. 23*

    Multiplicity distribution of produced gluons in deep inelastic scattering: main equations and their homotopy solutions for heavy nuclei

    Carlos Contreras🇨🇱 · Jose Garrido🇨🇱 · Eugene Levin🇮🇱

    In this paper we discuss the multiplicity distribution in the deep inelastic processes in the frame work of high energy QCD. We obtained three results. First, we get the new derivation of the equations for the cross sections of productions of $n$-cut Pomerons in the final states (${\sigma }_n$). These equations coincide with the equations that have been derived using the Abramovsky, Gribov and Kancheli (AGK) cutting rules but based on the dipole approach to QCD. Second, we developed the homotopy approach for finding the solutions to these equations. It consists with the analytic solution for the first iteration and the converge procedure of calculating the next iterations using computing. Third, we found the analytical solution for ${\sigma }_n$ at large $n\gtrsim N(z)=2N_{0}z\exp (z^2/(2\kappa ))$ with $z=\ln (r^2{Q}_s^2)$. Using this solution we calculate the entropy of the produced gluons at large $z$: $S_E=\ln \left(N(z)\right)$, where the saturation momentum $Q_s$ and all constants are discussed in the text.

    hep-phnucl-thPRD(2026)·2 citations
24. 24*

    Spacelike and timelike structure functions: a dispersive crossing relation

    Aniruddha Venkata🇩🇪

    Crossing symmetry suggests that deep inelastic scattering and semi inclusive electron-positron annihilation are governed by analytic continuations of a single forward amplitude. Drell, Levy, and Yan proposed that the hadronic tensor admits analytic continuation and demonstrated, in reasonable models, that connected contributions to the cross-section continue. They also identified obstructions to continuation of the current correlator. In this work we supplement their observation with a new dispersive proposal for analytic continuation of the correlator and, assuming polynomial boundedness, derive subtracted dispersion relations relating spacelike and timelike cross sections. We introduce a new factorized function that quantifies the obstruction to crossing and compute its hard kernel at lowest order. The resulting identity connects distribution functions in deep inelastic scattering to fragmentation functions in annihilation.

    hep-phhep-th1 citation
25. 25*

    Energy loss predicts no $v_2$ in small systems

    Ben Bert🇿🇦 · Coleridge Faraday🇿🇦 · W.A. Horowitz🇿🇦

    We present high-$p_T$ $R_{AB}$ and $v_2$ from a perturbative quantum chromodynamics-based energy loss model that includes event-by-event hydrodynamic evolution of the medium and small system size corrections to the energy loss. The model is calibrated on, and describes well, large system $R_{AA}$ and $v_2$ experimental data. The extrapolation of our model to $\mathrm{Ne}+\mathrm{Ne}$ and $\mathrm{O}+\mathrm{O}$ agrees quantitatively with recent experimental measurements of $R_{AA}$. Surprisingly, at high-$p_T$ our energy loss model predicts $v_2\approx 0$ for all symmetric and asymmetric small systems when extracted using either hard-hard or hard-soft two-particle correlations. We argue that all energy loss models will in general predict $v_2\approx 0$ when extracted using hard-soft correlations, which is the usual experimental method for measuring anisotropy in hadronic collisions, due to a generic geometric decorrelation between the hard and soft sector participant planes.

    hep-ph6 citations
26. 26*

    Gravitational waves from holographic first-order QCD phase transition with magnetic field

    Man-Man Sun🇨🇳 · Man-Li Tian🇨🇳 · Zhou-Run Zhu🇨🇳

    In this paper, we investigate the generation of gravitational waves (GWs) from a first-order QCD confinement-deconfinement phase transition under external magnetic field from holography. We analyze the GWs spectra across both hard wall and soft wall models for Jouguet detonations and non-runaway scenarios. Our results indicate that increasing the magnetic field shifts the spectral peak to lower frequencies. The predicted GWs signals are potentially detectable by observatories such as IPTA, SKA, BBO and NANOGrav. Decomposing the spectra reveals that sound waves typically dominate the signal around the peak frequency, bubble collisions prevail at spectral extremities, and the contribution from MHD turbulence is significant only for non-runaway bubble scenarios at high frequencies. This work suggests that magnetized QCD phase transitions are viable cosmological sources for observable GW backgrounds, offering a potential pathway to constrain primordial magnetic fields through future PTA observations.

    hep-phPRD(2026)·0 citations
27. 27*

    A Fast Method for Correlated Updates of Proton PDFs and the Strong Coupling ${\alpha }_s$

    Yao Fu🇺🇸 · Carl Schmidt🇺🇸 · C.--P. Yuan🇺🇸

    We present an extended version of the \texttt{ePump} framework that enables the simultaneous profiling of proton parton distribution functions (PDFs) and the strong coupling ${\alpha }_s$ using new experimental data. By promoting ${\alpha }_s$ to a fit parameter within the Hessian updating formalism, the method performs coherent updates of $\{\text{PDFs},{\alpha }_s\}$ while preserving parameter correlations and the full covariance structure. Validation studies based on CTEQ-TEA analyses with collider data demonstrate that the upgraded \texttt{ePump} accurately reproduces the shifts in PDFs, the preferred ${\alpha }_s(m_Z)$, and the associated uncertainty reductions obtained in full global fits, including those inferred from Lagrange--Multiplier scans; small deviations arise only for data sets whose ${\chi }^2$ profiles exhibit nonlinear behavior. Applications to representative collider measurements illustrate the impact on the gluon distribution and on precision observables such as the Higgs boson production cross section via gluon fusion. This enhanced framework provides a fast and reliable tool for assessing the effects of new data on the global QCD parameter space, offering near-global-fit accuracy at a fraction of the computational cost.

    hep-ph0 citations
28. 28*

    Jet quenching and its substructure dependence due to color decoherence

    Xiang-Pan Duan🇨🇳 · Lin Chen🇪🇸 · Guo-Liang Ma🇨🇳 · Carlos A. Salgado🇪🇸 · Bin Wu🇪🇸

    Motivated by color coherence and decoherence effects in the QCD medium, we propose a theoretical framework that combines vacuum-like emissions and medium-induced radiation to study jet quenching and its dependence on jet cone sizes and substructure. In our approach, a jet produced at a hard scale $Q$ first undergoes vacuum-like evolution, as described by the well-established generating-function method in the double logarithmic approximation. These vacuum-like emissions generate subjets at an infrared momentum scale $Q_0$. Each subjet then experiences medium-induced energy loss as described by the BDMPS-Z formalism. By modeling the QCD bulk medium using OSU (2+1)-dimensional viscous hydrodynamics and treating $Q_0$ together with the jet-quenching parameters at the initial proper time of the hydrodynamic evolution as free parameters, our approach provides a very good description of the inclusive jet modification factor $R_{AA}$ for large-radius jets and its dependence on jet substructure in 0-10% PbPb collisions at $\sqrt{s_{NN}}=5.02\mathrm{TeV}$, as measured by the ATLAS experiment.

    hep-phhep-exnucl-exnucl-th1 citation
29. 29*

    Kinky vortons in the 2HDM

    Richard A. Battye🇬🇧 · Steven J. Cotterill🇬🇧 · Adam K. Thomasson🇬🇧

    We construct and analyse two-dimensional, current-carrying ring solutions, known as kinky vortons, in the ${\mathbb{Z}}_2$-symmetric global two-Higgs-doublet model (2HDM). We demonstrate the existence of multiple dynamically stable configurations that persist under non-axially symmetric perturbations. These solutions are described with high accuracy by the thin string approximation and elastic string formalism, which correctly capture both their equilibrium radii and dynamical oscillation frequencies. Kinky vortons in the ${\mathbb{Z}}_2$-symmetric theory establish the viability of vorton solutions in a phenomenologically motivated extension of the Standard Model, and should provide a computationally tractable proxy for vortons in the $U(1)$-symmetric 2HDM. In addition, we identify a composite domain wall configuration in which localized condensates are supported on secondary domain walls existing on a ${\mathbb{Z}}_2$ wall, suggesting a mechanism by which kinky-vorton-like defects could arise in a three dimensional setting.

    hep-phastro-ph.COhep-thPRD(2026)·0 citations
30. 30*

    A perturbative framework to probe infrared sensitivity in non-Abelian gauge theories

    Duarte Fontes🇩🇪 · Dennis Horstmann🇩🇪 · Kirill Melnikov🇩🇪 · Davide Maria Tagliabue🇩🇪

    Understanding the infrared sensitivity of perturbative predictions in QCD is important for assessing the magnitude of possible non-perturbative power corrections to processes with large momentum transfer. In renormalon models, this sensitivity can be related to computable dependences of perturbative quantities on a small gluon mass. However, this procedure cannot be applied to collider processes with gluons at the Born level. To address this problem, we promote the gluon mass to a parameter of a consistent non-Abelian quantum field theory where the gauge symmetry is spontaneously broken through the Higgs mechanism. Working in the limit in which the gluon mass $m_{\mathrm{g}}$ is the smallest dimensionful parameter, we compute through two loops the $\mathcal{O}(m_{\mathrm{g}})$ contributions to the relation between the pole and $\overline{\mathrm{MS}}$ masses of a heavy quark and to the relation between corresponding field counterterms. We expect that the proposed framework will provide a useful laboratory for probing linear infrared sensitivity of collider observables in QCD.

    hep-phJHEP(2026)·0 citations
31. 31*

    The energy-momentum tensor in a classical model of the electron

    Grace Gardella🇺🇸 · Mira Varma🇺🇸 · Peter Schweitzer🇺🇸

    We show that the leading non-analytic terms in the small-t expansion of the energy momentum tensor (EMT) form factors of an electrically charged particle in QED can be correctly derived in a classical model of the electron by Bialynicki-Birula. Based on the lucidity of the employed exactly solvable model, we comment also on the recently proposed concept of a regularized proton D-term.

    hep-phPRD(2026)·0 citations
32. 32*

    Dispersion Relations of Collective Flavor Excitations in Dense Neutrino Media

    Anson Kost🇺🇸 · Huaiyu Duan (UNM)🇺🇸

    We apply the Landau damping theory to collective flavor excitations in dense neutrino media. We demonstrate explicitly that the (meta-)stable modes of the collective flavor excitations in a physical dense neutrino gas are indeed weakly damped. We show that there should in general exist infinitely many collective flavor excitation modes most of which are damped. In a neutrino gas with one or more zero crossings in the distribution of the difference of the (neutrino) lepton numbers (DLNs), the least damped resonant modes and the (originally) metastable modes at certain wave numbers can suffer from inverse Landau damping and thus become unstable. We also introduce the concept of convoluted DLN distributions which can be used to understand the physical origin of the slow and fast flavor instabilities in dense neutrino media in core-collapse supernovae and neutron star mergers.

    hep-phastro-ph.HE1 citation
33. 33*

    Neutrino Oscillation Parameter Estimation Using Structured Hierarchical Transformers

    Giorgio Morales🇫🇷 · Gregory Lehaut🇫🇷 · Antonin Vacheret🇫🇷 · Frederic Jurie🇫🇷 · Jalal Fadili🇫🇷

    Neutrino oscillations encode fundamental information about neutrino masses and mixing parameters, offering a unique window into physics beyond the Standard Model. Estimating these parameters from oscillation probability maps is, however, computationally challenging due to the maps' high dimensionality and nonlinear dependence on the underlying physics. Traditional inference methods, such as likelihood-based or Monte Carlo sampling approaches, require extensive simulations to explore the parameter space, creating major bottlenecks for large-scale analyses. In this work, we introduce a data-driven framework that reformulates atmospheric neutrino oscillation parameter inference as a supervised regression task over structured oscillation maps. We propose a hierarchical transformer architecture that explicitly models the two-dimensional structure of these maps, capturing angular dependencies at fixed energies and global correlations across the energy spectrum. To improve physical consistency, the model is trained using a surrogate simulation constraint that enforces agreement between the predicted parameters and the reconstructed oscillation patterns. Furthermore, we introduce a neural network-based uncertainty quantification mechanism that produces distribution-free prediction intervals with formal coverage guarantees. Experiments on simulated oscillation maps under Earth-matter conditions demonstrate that the proposed method is comparable to a Markov Chain Monte Carlo baseline in estimation accuracy, with substantial improvements in computational cost (around 240$\times$ fewer FLOPs and 33$\times$ faster in average processing time). Moreover, the conformally calibrated prediction intervals remain narrow while achieving the target nominal coverage of 90%, confirming both the reliability and efficiency of our approach.

    hep-phcs.LG0 citations
34. 34*

    CPT Violation, Mirror World and Implications for Baryon Asymmetry

    M. M. Chaichian🇫🇮 · M. Gogberashvili🇬🇪 · M. N. Mnatsakanova🇷🇺 · T. Tsiskaridze🇬🇪

    We propose a novel model in which the Universe is created as a pair of coordinate-reversed counterparts, forming a globally CPT-symmetric system that permits local CPT violations within each sector. This framework naturally introduces a mirror universe with opposite chiralities and reversed microscopic time coordinates, providing a geometric interpretation of time reversal without relying on initial-final state interchange. We investigate the consequences of local CPT violation in each universe, which induces a mass difference between the real inflaton and anti-inflaton fields. Such an asymmetry can modify reheating temperatures and naturally generate the observed matter-antimatter asymmetry in both universes.

    hep-phgr-qchep-thEPJC(2026)·0 citations
35. 35*

    Dark Matter Detection Using Phonon Sensing in Amorphous Materials

    Itay M. Bloch🇨🇭 · Simon Knapen🇺🇸 · Xinran Li🇨🇳 · Amalia Madden🇺🇸 · Giacomo Marocco🇺🇸

    We present a concept for a tabletop-scale detector with an amorphous target designed to search for dark matter absorption into phonon excitations. In crystalline materials, absorption occurs only at narrow resonances where the dark matter mass matches a zero momentum optical phonon mode, whereas amorphous targets provide a broadband response that can substantially enhance the absorption rate away from these resonances. The predicted backgrounds arise from the relaxation of disorder-induced metastable defects in the amorphous target, as well as from low-energy noise intrinsic to superconducting phonon sensors. A prototype detector with a target mass of only a few $\mu$g could provide broadband sensitivity to dark photon absorption across the 50 meV-200 meV mass range, probing up to two orders of magnitude beyond existing constraints.

    hep-phphysics.ins-det0 citations
36. 36*

    What does it take to have $N_{\mathrm{eff}}<3$ at CMB times?

    Miguel Escudero🇨🇭 · Maksym Ovchynnikov🇨🇭 · Neal Weiner🇺🇸

    The vast majority of extensions of the Standard Model affecting the number of effective relativistic neutrino species ($N_{\mathrm{eff}}$) do so additively, namely, they enhance this quantity with some light state contributing to dark radiation. In this work, we consider precisely the opposite case: new physics scenarios that can lead to $N_{\mathrm{eff}}<3$ that are consistent with all known cosmological, astrophysical, and laboratory data. We are motivated by three main reasons: 1) a recent measurement from ACT and SPT in combination with Planck that leads to $N_{\mathrm{eff}}=2.81\pm 0.12$, 2) by a new and powerful measurement of the primordial helium abundance, which anchors $N_{\mathrm{eff}}$ to be very close to the Standard Model value one second after the Big Bang, 3) by the deployment of the Simons Observatory which will provide precise tests of the radiation content in the Universe and which may detect with a high significance cosmologies with $N_{\mathrm{eff}}<3$. We survey the main theoretical possibilities and find that only a few simple scenarios can consistently give $N_{\mathrm{eff}}=2.81\pm 0.12$. One class consists of thermal electrophilic relics with masses $m\sim 8-13\mathrm{MeV}$. Another consists of out-of-equilibrium particles decaying to $e^{+}{e}^{-}$ or $\gamma \gamma$, with a rather particular lifetime $0.05\mathrm{s}\lesssim \tau \lesssim 3\min$, mass $250\mathrm{MeV}\lesssim m\lesssim 600\mathrm{MeV}$, and abundance $\rho /{\rho }_{\gamma }\sim 0.1$ at decay. Thermal electrophilic particles are especially interesting because they can account for the dark matter in the Universe and can be tested in experiments such as SENSEI, DAMIC-M, and Oscura, and their portals to the visible sector at experiments such as NA64 and LDMX. We conclude that if the Simons Observatory confirms that $N_{\mathrm{eff}}\simeq 2.8$, it will point to very specific extensions of the Standard Model.

    hep-phastro-ph.CO7 citations
37. 37*

    Kinetic Isocurvature Perturbation

    Kyu Jung Bae🇰🇷 · Dhong Yeon Cheong🇰🇷 · Jinn-Ouk Gong🇰🇷 · Keisuke Harigaya🇺🇸 · Chang Sub Shin🇰🇷

    We formulate a new class of primordial perturbations called $\text{kinetic isocurvature perturbations}$, where the mass density of dark matter is constant relative to the photon number density while the kinetic energy of dark matter fluctuates in space. Such perturbations naturally arise in scenarios where a nonrelativistic heavy field decays into relativistic dark matter particles with a spatially modulated rate. As dark matter cools and becomes nonrelativistic, these fluctuations in kinetic energy leave large-scale density perturbations essentially unaffected and therefore evade the Cosmic Microwave Background bounds on isocurvature perturbations, yet survive as spatial variations in the free-streaming scale, resulting in patch-by-patch variation of the matter power spectrum.

    hep-phastro-ph.CO1 citation
38. 38*

    Slow-down of expanding bubbles in the early Universe

    Nabeen Bhusal🇩🇪 · Simone Blasi🇩🇪 · Thomas Konstandin🇩🇪 · Enrico Perboni🇩🇪 · Jorinde van de Vis🇨🇭

    We study slow-down effects for bubbles formed in a cosmological first-order phase transition (PT) focusing on deflagrations and hybrids, where the bubble wall is preceded by a shockwave of heated plasma. Slow-down has been observed in multi-bubble simulations together with a suppression of gravitational wave (GW) emission, mostly for slow walls. We study the impact of the shock waves on the wall velocity around percolation, by considering steady-state single-bubble solutions and incorporating the possible heating effects by two different mechanisms. First, we investigate the slow-down experienced by a bubble expanding into an impeding shockwave, where the temperature is higher than at nucleation, and the fluid is no longer at rest. Taking into account such heating and kinematic effects, we find that the most significant slow-down occurs for the fastest walls, and thus cannot explain the suppression of the GWs observed in the simulations. However, these effects are stronger for PTs with a sizeable change in degrees of freedom unlike what is usually implemented in simulations, suggesting that the degrees of freedom can be an important additional parameter for characterizing the GW spectrum. For the second slow-down mechanism, we study heated droplets of false vacuum that shrink towards the end of the PT. By implementing a suitable boundary condition motivated by energy conservation, we show how the droplet velocity, interpreted here as the late-time velocity of the bubble walls, can be predicted from the properties of the initial deflagration/hybrid, in remarkable agreement with numerical simulations. Droplets are found to shrink more slowly for stronger PTs and slower deflagrations, with mild dependence on the change of degrees of freedom. Such slow droplets naturally correlate with a suppression of GWs, while geometrical properties such as the shock width play an important role as well.

    hep-phastro-ph.COJCAP(2026)·2 citations
39. 39*

    MadNIS at NLO

    Giovanni De Crescenzo🇩🇪 · Javier Mariño Villadamigo🇩🇪 · Nina Elmer🇩🇪 · Theo Heimel🇧🇪 · Tilman Plehn🇩🇪 · Ramon Winterhalder🇮🇹 · Marco Zaro🇮🇹

    We combine fast amplitude surrogates with neural importance sampling to accelerate NLO calculations. For virtual corrections, a learned ratio to the Born matrix element with calibrated uncertainties guarantees reliable precision across phase space. For real emission, we stick to the standard FKS subtraction and train sector-conditioned surrogates of the regularized integrands away from divergences. MadNIS then uses multi-channel mappings and FKS sectors as conditions. We validate our approach for electron-positron scattering to three and four jets and find significant speed-ups and variance reduction in the integration.

    hep-ph14 citations
40. 40*

    Casimir Geometry as a Probe of Short Range Forces

    Xiaolin Ma🇯🇵 · Volodymyr Takhistov🇯🇵 · Hideo Iizuka🇯🇵

    Casimir force searches provide among the most sensitive laboratory probes of new short range interactions. Existing constraints rely almost exclusively on a single geometry. We show that Casimir geometry constitutes an independent observable, as Yukawa-type interactions and Casimir background exhibit different geometric scaling for bulk forces and surface quantum effects. We derive the first constraints from sphere-sphere and plate-plate geometries, thereby completing the canonical set of Casimir geometries, obtaining the most stringent Casimir-based bounds for $\lambda \lesssim 10^{-8}\mathrm{m}$. Our results establish geometry as a new handle for systematic searches for short range forces.

    hep-phhep-exquant-ph0 citations
41. 41*

    Inside the Black Box of Big Bang Nucleosynthesis: A Comprehensive Sensitivity Atlas for the Precision Era

    Anne-Katherine Burns🇪🇸

    In this study we present a comprehensive sensitivity atlas for Big Bang Nucleosynthesis (BBN) in which we quantify the dependence of the primordial abundances of helium-4, deuterium, and lithium-7 as well as $N_{\mathrm{eff}}$ on variations in 14 fundamental particle physics and cosmological parameters and 63 thermonuclear reaction rates. We use the publicly available BBN code \faGithub \href{https://github.com/vallima/PRyMordial}{\,\texttt{PRyMordial}} to compute each sensitivity using two nuclear reaction rate compilations and two weak-rate normalization schemes, and provide a model independent reference applicable to Beyond the Standard Model (BSM) models in which MeV scale physics is modified. In addition, we rank each parameter's contribution to the theoretical uncertainty budget. We compare our predictions against the latest observational determinations of the primordial abundances, including a recent LBT measurement of the helium-4 abundance \cite{Aver:2026dxv} which roughly halves the observational uncertainty relative to previous determinations. We present these results both fixing $\Delta N_{\mathrm{eff}}$ at its Standard Model (SM) value, and allowing it to be a free parameter using the latest uncertainty from the combined CMB+BAO+BBN 2026 value \cite{Goldstein:2026iuu}. When $\Delta N_{\mathrm{eff}}$ is allowed to be a free parameter, it dominates the theoretical uncertainty of the helium-4 abundance, highlighting the importance of upcoming observations from the Simons Observatory \cite{SimonsObservatory:2025wwn}. As illustrative applications, we examine the deuterium tension and the Lithium Problem in light of our sensitivity analysis. The full set of numerical results and figures is publicly available on GitHub \faGithub \href{https://github.com/Anne-KatherineBurns/bbn-sensitivity-atlas}{\,\texttt{bbn-sensitivity-atlas}}.

    hep-phastro-ph.COPhys.Rept.(2026)·0 citations
42. 42*

    Planck-Scale Effects on Nucleon Decay in Minimal Supersymmetric SU(5)

    John Ellis🇬🇧 · Jason L. Evans🇨🇳 · Shihwen Hor🇨🇳 · Natsumi Nagata🇯🇵 · Keith A. Olive🇺🇸

    We examine the impact on the phenomenology of the minimal supersymmetric SU(5) Grand Unified Theory (GUT) of dimension-5 operators with coefficients suppressed by the Planck mass scale, with particular emphasis on predictions for nucleon decay. We incorporate dimension-5 operators in both the Higgs sector and the Yukawa interactions in the theory, and take account of the constraints from gauge coupling measurements, the mass of the Higgs boson, fermion masses and the cold dark matter density. We consider two scenarios for soft supersymmetry breaking: the constrained minimal supersymmetric extension of the Standard Model (CMSSM) and the Non-Universal Higgs Model (NUHM). We present predictions for the nucleon decay modes $p\to {\pi }^0{e}^{+},{\pi }^0{\mu }^{+},K^{+}\bar{\nu },{\pi }^{+}\bar{\nu }$, $K^0{e}^{+},K^0{\mu }^{+}$ and $n\to {\pi }^0\bar{\nu }$, ${\pi }^{-}{e}^{+},K^0\bar{\nu }$, which we compare with both the present experimental sensitivities and those projected for the JUNO and Hyper-Kamiokande experiments. We find that these experiments may have interesting possibilities for discovering several of these decay modes.

    hep-phEPJC(2026)·1 citation
43. 43*

    The impact of gamma-ray propagation effects on indirect dark matter searches

    Ignacio Martínez López🇪🇸 · Rafael Alves Batista🇫🇷 · Miguel A. Sánchez-Conde🇪🇸 · Antonio Juan Rubio-Montero🇪🇸

    In this work, we investigate dark matter (DM) detection in the context of weakly interacting massive particles (WIMPs). Upon annihilation, WIMPs generate cascades of secondary particles through various channels, many of which culminate in the production of gamma rays. As these gamma rays travel toward Earth, their spectra are reshaped by interactions with the intervening medium. While current models typically account for attenuation via pair production on the extragalactic background light, they often neglect the fate of the resulting electrons and positrons, specifically subsequent inverse Compton scattering of these secondary particles, which can regenerate high-energy gamma rays. Here, we revisit the predicted gamma-ray fluxes from WIMP annihilation by performing a more detailed treatment of propagation effects. We show that for distant sources and annihilation channels such as ${\tau }^{+}{\tau }^{-}$, the full treatments can significantly alter the observed gamma-ray flux, by up to a factor of three orders of magnitude for heavy WIMPs. This has an impact on current dark matter limits derived without taking into account propagation effects, depending on the considered WIMP mass and annihilation channel. Our study demonstrates the importance of a detailed propagation treatment for indirect dark matter searches, and the need to account for such effects in order to obtain accurate, more reliable dark matter signal predictions and exclusion limits.

    ↳ astro-ph.HEhep-ph0 citations
44. 44*

    Uncertainty quantification of holographic transport and energy loss for the hot and baryon-dense QGP

    Musa R. Khan🇺🇸 · Ayrton Nascimento🇧🇷 · Yumu Yang🇺🇸 · Joaquin Grefa🇺🇸 · Mauricio Hippert🇧🇷 · Jorge Noronha🇺🇸 · Claudia Ratti🇺🇸 · Romulo Rougemont🇧🇷

    We investigate several transport coefficients across the phase diagram of a holographic Einstein-Maxwell-Dilaton (EMD) model of hot and dense QCD with $N_f=2+1$ flavors. Our results are obtained from an open-source implementation of this model in C++, publicly available as a module within the MUSES Framework. This code includes a new numerical method to extract thermodynamic quantities from near-boundary asymptotics in holographic models, introduced here for the first time, which greatly improves numerical stability and performance in comparison to earlier implementations. Thanks to this improved technique, we are able to compute results for many realizations of our holographic model, sampled from a Bayesian posterior distribution constrained by lattice QCD results at zero chemical potential. This allows us to propagate lattice QCD error bars to predictions of transport coefficients in a wide window of temperature and baryon chemical potential, covering the crossover region, the neighborhood of the predicted critical point, and the line of first-order phase transition. The physical observables include baryon and thermal conductivities, baryon diffusion, shear and bulk viscosities, the jet-quenching parameter, the heavy-quark drag force, and Langevin diffusion coefficients. At vanishing baryon density, we compare our results to estimates extracted by the JETSCAPE Collaboration from heavy-ion data, with which we find good agreement.

    ↳ nucl-thhep-phhep-th4 citations
45. 45*

    Singular structures and causality of the Schwarzschild Green's function in the frequency domain

    Romeo Felice Rosato🇮🇹 · Marina De Amicis🇨🇦 · Paolo Pani🇮🇹

    We study two singular spectral components of the Green's function of a Schwarzschild black hole and their interpretation in the frequency domain: (i) the low-frequency branch cut, which yields corrections to Price's law tails in the form of inverse power laws weighted by logarithmic terms; and (ii) the quasinormal-mode spectrum, which generates a redshifted response for sources extended toward the horizon. We show that the frequency-domain Green's function can be naturally interpreted in terms of greybody factors, providing the first analytical justification for recent phenomenological ringdown models based on these quantities. For sources localized outside the peak of the potential barrier, we identify two tail contributions activated with a time delay, arising from backscattering of the prompt response and of the ringdown signal. We show that corrections to Price's law can be relevant at intermediate times, when the ringdown still dominates the waveform. For sources localized inside the potential barrier peak, the tail is suppressed and the signal is instead dominated by quasinormal frequencies. In this regime, these spectral components produce both the ordinary quasinormal-mode ringdown and an infinite tower of exponentially decaying terms governed by the horizon surface gravity, the so-called redshift terms. We demonstrate that this component is not screened by geometric features of the background spacetime and persists up to late times, as supported by numerical investigations of perturbative waveforms. Our results provide a mathematical foundation for phenomenological modeling of the branch-cut contribution at intermediate times, which is relevant for prospective observations of tails, and strong evidence for the presence of redshifted components from intermediate to late times.

    ↳ gr-qcastro-ph.HEhep-phmath-ph+1PRD(2026)·13 citations
46. 46*

    Unfolding with a Wasserstein Loss

    Katy Craig🇺🇸 · Benjamin Faktor🇺🇸 · Benjamin Nachman🇺🇸

    Data unfolding -- the removal of noise or artifacts from measurements -- is a fundamental task across the experimental sciences. Of particular interest are applications in physics, where the dominant approach is Richardson-Lucy (RL) deconvolution. The classical RL approach aims to find denoised data that, once passed through the noise model, is as close as possible to the measured data in terms of Kullback-Leibler (KL) divergence. This requires that the support of the measured data overlaps with the output of the noise model, a hypothesis typically enforced by binning, which introduces numerical error. As a counterpoint, the present work studies an alternative formulation using a Wasserstein loss. We establish sharp conditions for existence and uniqueness of optimizers, answering open questions of Li, et al., regarding necessary conditions for uniqueness in the case of transport map noise models. We then develop a provably convergent generalized Sinkhorn algorithm to compute approximate optimizers. Our algorithm requires only empirical observations of the noise model and measured data and scales with the size of the data, rather than the ambient dimension. Numerical experiments on one- and two-dimensional problems inspired by jet mass unfolding in particle physics demonstrate that the optimal transport approach offers robust, accurate performance compared to classical RL deconvolution, particularly when binning artifacts are significant.

    ↳ math.OChep-phstat.ML1 citation
47. 47*

    Production correlation of light (hyper-)nuclei in Au-Au collisions from the RHIC Beam Energy Scan

    Jiang-He Qiao🇨🇳 · Jian-Yu Liu🇨🇳 · Yan-Ting Feng🇨🇳 · Feng-Lan Shao🇨🇳 · Rui-Qin Wang🇨🇳

    Based on nucleons ($p$, $n$) and hyperons ($\Lambda$, ${\Omega }^{-}$) formed at kinetic freeze-out from a quark combination model, we systematically study the production of light nuclei and hyper-nuclei in the hadronic coalescence picture. We present the analytical formula of the nucleus momentum distribution of two-body coalescence and that of three-body coalescence. We explain the experimental data of the transverse momentum spectra of deuteron ($d$), triton ($t$), helium-3 (${}^3$He) and hypertriton (${}_{\Lambda }^3$H) measured in Au-Au collisions from the RHIC Beam Energy Scan I and II, and also provide the corresponding predictions of different $\Omega -$hypernuclei $H(p{\Omega }^{-})$, $H(n{\Omega }^{-})$ and $H(pn{\Omega }^{-})$. We further study the production correlations of different species of light (hyper-)nuclei and discuss their interesting behaviors as a function of collision energy.

    ↳ nucl-thhep-exhep-ph0 citations
48. 48*

    Critical dynamics of the superfluid phase transition in Model F

    Chandrodoy Chattopadhyay🇺🇸 · Robert Maguire · Josh Ott🇺🇸 · Thomas Schaefer🇺🇸 · Vladimir V. Skokov🇺🇸

    We describe numerical simulations of the critical dynamics near the superfluid phase transition. The calculations are based on an implementation of a stochastic hydrodynamic theory known as model F in the classification of Hohenberg and Halperin. This theory is expected to describe dynamic scaling near the lambda transition in liquid ${}^4$He, Bose-Einstein condensation in ultracold atomic gases, and the superfluid transition in the unitary Fermi gas. Our simulation is based on a Metropolis algorithm previously applied to the critical endpoint of the liquid-gas phase transition in ordinary fluids. In the model E truncation of model F we obtain the expected dynamical exponent $z\simeq 3/2$. We observe the emergence of a propagating second sound mode at the phase transition. The second sound diffusivity $D_s$ is consistent with the scaling relation $D_s\sim {\xi }^{x_{\kappa }}$, where $\xi$ is the correlation length and $x_{\kappa }=1/2$.

    ↳ cond-mat.quant-gashep-phnucl-thPRA(2026)·2 citations
49. 49*

    Bayesian extraction of TMC-free collectivity in p+p and p+Pb collisions at the LHC

    Shuang Guo🇨🇳 · Jia-Lin Pei🇨🇳 · Guo-Liang Ma🇨🇳 · Adam Bzdak🇵🇱

    A central challenge in understanding the origin of collective flow-like signatures in small collision systems calls for a reliable method to disentangle genuine collective flow from substantial background correlations, especially those arising from transverse momentum conservation (TMC). A Bayesian inference framework is developed to integrate TMC calculations with the LHC-ATLAS data on long-range multiparticle azimuthal correlation observables, thereby extracting genuine collective flow in small systems. Our analysis indicates that while the genuine elliptic and triangular flow ($v_2$ and $v_3$) are similar, the $p$+$p$ and $p$+Pb systems exhibit distinct TMC backgrounds, TMC-flow interplay, and $v_2$--$v_3$ correlations. We demonstrate that the genuine $v_2$ and $v_3$ are well described by the measured four-particle $v_2\{4\}$ and two-particle $v_3\{2\}$ in $p$+Pb collisions, whereas these measurements systematically underestimate the genuine flow in $p$+$p$ collisions, due to competing contributions from TMC effects. This establishes a robust and data-driven approach, providing renewed theoretical insight into collective behavior free from TMC contamination in small collision systems.

    ↳ nucl-thhep-phnucl-ex0 citations
50. 50*

    Multimessenger Concordance for the Cygnus Region as the Source of the Cosmic-Ray Knee

    Luis E. Espinosa Castro🇮🇹 · Kotha Murase🇺🇸 · Carlo Rizza🇮🇹 · Francesco L. Villante🇮🇹 · Vittoria Vecchiotti🇮🇹 · Giulia Pagliaroli🇮🇹

    The origin of the cosmic-ray (CR) knee remains one of the central open questions in particle astrophysics. Recent measurements by the Large High Altitude Air Shower Observatory revealed a pronounced feature in the proton spectrum at $\sim 3-4$~PeV, while observations of diffuse gamma rays above $100$~TeV do not exhibit a corresponding spectral break. This apparent discrepancy challenges the standard interpretation, in which the local CR distribution is representative of the Galactic CR sea. Here, we investigate whether the CR knee can instead originate from the Cygnus region as a nearby PeVatron. By combining CR measurements at Earth with very-high-energy gamma-ray observations from LHAASO and the Tibet-AS$\gamma$ experiment, we identify an additional hard gamma-ray component in the inner Galaxy consistent with a source located in the Cygnus region. We show that our results provide a concordance multimessenger picture. The required properties are compatible with the PeVatron candidate detected by LHAASO in the Cygnus bubble and with the Galactic neutrino flux observed by the IceCube Neutrino Observatory.

    ↳ astro-ph.HEhep-ph2 citations
51. 51*

    Charmed baryon decays at Belle and Belle II

    Jaeyoung Kim (on behalf of the Belle II Collaboration)🇰🇷

    Belle and Belle II experiments have collected $e^{+}{e}^{-}$ collision data with center-of-mass energies at or near the ${\rm Y}(4S)$ resonance. Using total $1.4{\mathrm{ab}}^{-1}$ combined dataset, we present new measurements of branching fractions for ${\Xi }_c^{0/+}$ and ${\Lambda }_c^{+}$ baryons, including several first observations. Additionally, we report the initial search for $CP$ violation in singly Cabibbo-suppressed three-body decays of charmed baryons, providing a test of $U$-spin symmetry.

    ↳ hep-exhep-phhep-thJ.Subatomic Part.Cosmol.(2026)·0 citations
52. 52*

    Inflationary phase transitions in the early Universe: A Bayesian study with space-based gravitational-wave detectors

    Qingyuan Liang🇨🇳 · Chen Yang🇨🇳 · Haipeng An🇨🇳 · Huai-Ke Guo🇨🇳

    Inflationary phase transitions can generate a stochastic gravitational-wave background that probes primordial physics. We study the detectability and parameter reconstruction of such a signal with a space-based gravitational-wave detector. Using a Taiji-like mission as a benchmark, we construct a realistic data-analysis framework that includes instrumental noise, astrophysical foregrounds and backgrounds, and the $A$, $E$, and $T$ time-delay interferometry channels. The target signal is described in a minimal, model-independent form and analyzed using both Fisher-matrix forecasts and Bayesian inference with nested sampling. We quantify detection significance and parameter-recovery thresholds, showing that, while detection is achievable at moderate signal-to-noise ratios, stronger signals provide more reliable parameter reconstruction. These results offer a realistic assessment of the capability of future space-based missions to probe inflationary phase transitions through stochastic gravitational radiation.

    ↳ astro-ph.COhep-phPRD(2026)·1 citation
53. 53*

    Reaction Studies of Lepton Number Violation

    Horst Lenske🇩🇪

    Nuclear isotensor spectroscopy as accessible in nuclear double charge exchange (DCE) reactions is indispensable for quantitative studies of lepton number violation as in double beta decay (DBD). For such studies heavy ion double single charge exchange (DSCE) and direct Majorana double charge exchange (MDCE) reactions are discussed. Isotensor two-body transition densities are investigated for the first time. Pion-potentials, mirroring neutrino potentials, and isotensor short range correlations are explored. Lepton DCE (LDCE) reactions on nuclei at accelerators are introduced as a promising new approach to investigate lepton number violation.

    ↳ nucl-thhep-phProceedings of the Mayorana Workshop, Mod…·0 citations
54. 54*

    Exact center symmetry and first-order phase transition in QCD with three degenerate dynamical quarks

    Gergely Endrodi🇩🇪 · Guy D. Moore🇩🇪 · Adam Pieczynski🇩🇪 · Alessandro Sciarra🇩🇪

    We study QCD with three degenerate flavors of dynamical quarks using first-principles lattice simulations. For a specific choice of imaginary isospin chemical potential, this theory possesses an exact center symmetry, just like pure gauge theory. This exact symmetry is expected to be intact at low temperatures and spontaneously broken in the high-temperature regime. By analyzing the finite-size scaling of the Polyakov loop distribution, obtained with a dedicated multi-histogram approach, we demonstrate that there is a first-order deconfinement phase transition in between. Our results are obtained employing stout-smeared rooted staggered quarks at one lattice spacing. Using simulations at different quark masses we sketch the behavior of QCD in the mass-isospin chemical potential plane, shedding new light on this corner of the fundamental phase diagram of the strong interactions and the relationship between chiral symmetry breaking and deconfinement.

    ↳ hep-lathep-phhep-thnucl-thPRD(2026)·2 citations
55. 55*

    Lattice study of the critical bubble in $\mathrm{SU}(8)$ deconfinement transition

    Kari Rummukainen🇫🇮 · Riikka Seppä🇫🇮 · David J. Weir🇫🇮

    Strongly coupled theories are of phenomenological interest, for example as dark matter candidates. Theories that can undergo first order thermal phase transitions are particularly appealing as potential sources of a stochastic gravitational wave background. Determining the expected gravitational wave signal from a first order phase transition requires accurate information on the bubble nucleation rate, but thus far for strongly coupled models these have relied on semiclassical methods. As a first step towards determining the nucleation rate, in this paper we study the confinement-deconfinement phase transition in a 4D SU(8) pure gauge model, using multicanonical Monte Carlo. Resolving the critical bubble for the first time in a pure Yang-Mills model, we determine the critical bubble probability and compare it to results from thin wall calculations. We also compare the effectiveness of different lattice pseudo-order parameters at resolving the condensation transition between the metastable phase and critical bubble branch, and point out the choice of order parameter is crucial to accurately resolve the critical configurations.

    ↳ hep-lathep-phPRD(2026)·2 citations
56. 56*

    A Conformal Bridge for the Light Transform of QCD Correlation Functions

    Hao Chen🇺🇸 · Pier Francesco Monni🇨🇭 · Zhaoyan Pang🇨🇳 · Gherardo Vita🇨🇭 · Hua Xing Zhu🇨🇳

    Understanding the link between correlation functions (CFs) of local operators and measurable collider correlators has emerged as a new opportunity in the study of gauge theory dynamics at colliders. While in Conformal Field Theories (CFTs) this connection is established by the light transform, the non-conformal nature of QCD complicates its use beyond the lowest perturbative order. We show that a continuation of the CFs to the Wilson-Fisher fixed point can be used as a method to overcome these obstacles, serving as a conformal bridge for the evaluation of the light transform. At the fixed point, the renormalized CF of four local operators features a variable drop and only depends on two conformal cross ratios, in line with a genuine CFT quantity. This allows us to exploit CFT techniques to perform, for the first time, its light transform at higher loop orders. Remarkably, the resulting collider correlator in four dimensions can be recovered from this result simply by using lower-loop data. We demonstrate this method by computing the back-to-back limit of the charge-charge correlation (QQC) at two loops in QCD through the light transform of the CF of four vector currents in the sequential light-cone limit, reproducing a recent prediction.

    ↳ hep-thhep-ph2 citations
57. 57*

    Primordial Non-Gaussianity and the Field-Level Cramer-Rao Bound

    Eugene Chen🇺🇸 · Daniel Green🇺🇸 · Vincent S. H. Lee🇺🇸

    Primordial non-Gaussianity is one of the most powerful probes of the inflationary epoch. The particle spectrum relevant to inflation, including masses and spins, is encoded in the precise form of statistical correlations of the adiabatic modes. Yet, in the presence of nonlinear structure formation, the optimal approach to measuring these signals remains unclear. Accurate modeling becomes crucial as late-time non-Gaussianty can become degenerate with primordial physics. Moreover, scale-dependent bias shows that information can move from non-Gaussian initial conditions to the amplitude of the Gaussian fluctuations. In this paper, we aim to clarify how primordial information is encoded in maps of galaxies. We use the field-level Cramer-Rao bound to investigate the ultimate limit of what can be extracted from realistic maps of the Universe. For local non-Gaussianity, we show that multi-tracer scale-dependent bias can exceed the sensitivity of conservative higher-point analyses. However, as expected, the multi-tracer analysis falls short of the optimal constraint when all the modes at the scale of the dark matter halos are included. We then forecast the potential reach of future surveys for equilateral and local non-Gaussianity. Equilateral in particular is highly sensitive to priors and modeling assumptions and can benefit dramatically from theoretical input such as the redshift evolution of the bias.

    ↳ astro-ph.COhep-phhep-th2 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.