Thu·Mar 14, 2024Thursday·March 14, 2024

1. 01*

   Top anomalous chromomagnetic dipole moment in a two Higgs doublet model

   T. Cisneros-Pérez🇲🇽 · A. Ramirez-Morales🇲🇽 · J. Montaño-Domínguez🇲🇽 · A. Gutiérrez-Rodríguez🇲🇽 · M. A. Hernández-Ruíz🇲🇽

   We review the anomalous Chromomagnetic Dipole Moment (CMDM) of the top quark in a Two Higgs Doublet Model (2HDM). We include interactions with the involvement of the extended CKM matrix in this model, we obtain new bonds for the future experimental measurements and theoretical considerations.

   hep-ph3 citations
2. 02*

   Nucleon charge and magnetisation distributions: flavour separation and zeroes

   Zhao-Qian Yao🇨🇳 · Daniele Binosi🇮🇹 · Zhu-Fang Cu · Craig D. Roberts🇨🇳

   A symmetry-preserving truncation of the quantum field equations describing hadron properties is used to deliver parameter-free predictions for all nucleon elastic electromagnetic form factors and their flavour separation to large values of momentum transfer, $Q^2$. The proton electric form factor, $G_E^p$, possesses a zero, whereas that of the neutron, $G_E^n$, does not. The difference owes to the behaviour of the Pauli form factor of the proton's singly-represented valence $d$-quark. Consequently, $G_E^n>G_E^p$ on a material large-$Q^2$ domain. These predictions can be tested in modern experiments.

   hep-phhep-exhep-latnucl-ex+1Fund.Res.(2026)·23 citations
3. 03*

   On the resolution of the sign of gluon polarization in the proton

   N. T. Hunt-Smith🇦🇺 · C. Cocuzza🇺🇸 · W. Melnitchouk🇺🇸 · N. Sato🇺🇸 · A. W Thomas🇦🇺 · M. J. White🇦🇺

   Recently the possible existence of negative gluon helicity, $\Delta g$, has been observed to be compatible with existing empirical constraints, including from jet production in polarized proton-proton collisions at RHIC, and lattice QCD data on polarized gluon Ioffe time distributions. We perform a new global analysis of polarized parton distributions in the proton with new constraints from the high-$x$ region of deep-inelastic scattering (DIS). A dramatic reduction in the quality of the fit for the negative $\Delta g$ replicas compared to those with positive $\Delta g$ suggest that the negative $\Delta g$ solution cannot simultaneously account for high-$x$ polarized DIS data along with lattice and polarized jet data.

   hep-phhep-exhep-latnucl-thPRL(2024)·20 citations
4. 04*

   Probing the heavy Higgs boson production and decay $H_0$ of the Bestest Little Higgs Model at the LHC and the FCC-hh

   E. Cruz-Albaro🇲🇽 · A. Gutiérrez-Rodríguez🇲🇽 · D. Espinosa-Gómez🇲🇽 · T. Cisneros-Pérez🇲🇽 · F. Ramírez-Zavaleta🇲🇽

   In the Bestest Little Higgs Model (BLHM) scenario, we analyze the branching ratios and production cross-section of the heavy Higgs boson $H_0$. The analysis is performed at the tree level and the one-loop level. In addition, we present results of the possible production of the heavy Higgs boson $H_0$ via gluon fusion for the center-of-mass energies and the integrated luminosities of the LHC, HE-LHC, HL-LHC, and FCC-hh. Our results show a very optimistic scenario for studying the $H_0$ scalar predicted by the BLHM and for the energies and luminosities of current and future hadron colliders.

   hep-phPRD(2024)·4 citations
5. 05*

   NNLO QCD corrections to $\Delta {\Gamma }_s$ in the $B_s-{\overline{B}}_s$ system

   Marvin Gerlach🇩🇪 · Ulrich Nierste🇩🇪 · Pascal Reeck🇩🇪 · Vladyslav Shtabovenko🇩🇪 · Matthias Steinhauser🇩🇪

   This report summarises recent advances made in the calculation of the NNLO QCD corrections to the width difference $\Delta {\Gamma }_s$ in the $B_s-{\overline{B}}_s$ system. The inclusion of the effects due to current-current operators leads to an updated prediction of $\Delta {\Gamma }_s=(0.076\pm 0.017){\text{ps}}^{-1}$, which narrows the gap between theory and experiment.

   hep-ph4 citations
6. 06*

   Suppression of diffraction in deep-inelastic scattering on nuclei and dynamical mechanism of leading twist nuclear shadowing

   V. Guzey (Jyvaskyla U. and Helsinki Inst. of Phys.)🇫🇮 · M. Strikman (Penn State U.)🇺🇸

   Using the leading twist approach (LTA) to nuclear shadowing, we calculate the ratios of diffractive and usual parton distributions for a heavy nucleus (Pb) and the proton, $R_{A/p}=(f_{i/A}^{D(3)}/f_{i/A})/(f_{i/p}^{D(3)}/f_{i/p})$, for coherent and summed (coherent plus quasi-elastic) nuclear deep-inelastic scattering. We find that $R_{A/p}\approx 0.5-1$ for quarks as well as for the ratio of the diffractive and total cross sections $[(d{\sigma }_{\mathrm{diff}}/d{M}_X^2)/{\sigma }_{\mathrm{tot}}{]}_{eA}/[(d{\sigma }_{\mathrm{diff}}/d{M}_X^2)/{\sigma }_{\mathrm{tot}}{]}_{ep}$ and $R_{A/p}\approx 0.5-1.3$ for gluons in a broad range of $x$, including the kinematics of the Electron-Ion Collider, which reaffirms the difference from the nuclear enhancement of $R_{A/p}$ predicted in the gluon saturation framework. We demonstrate that the magnitude of $R_{A/p}$ is controlled by the cross section of the interaction of hadronic fluctuations of the virtual photon with target nucleons, which explains an enhancement of $R_{A/p}$ in the color dipole model and its suppression in LTA. We argue that the black disk limit corresponds to $R_{A/p}=1$ and $R_{A/p}^{\mathrm{coh}}=0.86$ for the summed and coherent scattering, respectively. Relying on an intuitive definition of the saturation scale, we show that the ratio of the saturation scales of a heavy nucleus and proton $Q_{sA}^2(b)/Q_{sp}^2(b)\approx 1$ at small impact parameters $b$ due to the strong leading twist nuclear shadowing and diluteness of the nuclear density.

   hep-phhep-exnucl-exJHEP(2024)·4 citations
7. 07*

   Decoupling of the structure functions in momentum space based on the Laplace transformation

   G.R.Boroun🇮🇷 · Phuoc Ha🇺🇸

   Using Laplace transform techniques, we describe the determination of the longitudinal structure function $F_L(x,Q^2)$, at the leading-order approximation in momentum space, from the structure function $F_2(x,Q^2)$ and its derivative with respect to $\ln Q^2$ in a kinematical region of low values of the Bjorken variable $x$. Since the $x$ dependence of $F_2(x,Q^2)$ and its evolution with $Q^2$ are determined much better by the data than $F_L(x,Q^2)$, this method provides both a direct check on $F_L(x,Q^2)$ where measured, and a way of extending $F_L(x,Q^2)$ into regions of $x$ and $Q^2$ where there are currently no data. In our calculations, we ultilize the Block-Durand-Ha parametrization for the structure function $F_2(x,Q^2)$ [M. M. Block, L. Durand and P. Ha, Phys.Rev.D {\bf89}, 094027 (2014)]. We find that the Laplace transform method in momentum space provides correct behaviors of the extracted longitudinal structure function $F_L(x,Q^2)$ and that our obtained results are in line with data from the H1 Collaboration and other results for $F_L(x,Q^2)$ obtained using Mellin transform method.

   hep-phPRD(2024)·13 citations
8. 08*

   Electroweak Evolution Equations and Isospin Conservation

   Paolo Ciafaloni🇮🇹 · Giampaolo Co'🇮🇹 · Dimitri Colferai🇮🇹 · Denis Comelli🇮🇹

   In processes taking place at energies much higher than the weak scale, electroweak corrections can be taken into account by using electroweak evolution equations, that are analogous to the DGLAP equations in QCD. We show that weak isospin conservation in these equations imposes to modify the expressions of the splitting functions commonly used in the literature. These modifications have a profound impact on the parton distribution functions.

   hep-phhep-exhep-thJHEP(2024)·7 citations
9. 09*

   BHAC-QGP: three-dimensional MHD simulations of relativistic heavy-ion collisions, I. Methods and tests

   Markus Mayer🇩🇪 · Ashutosh Dash🇩🇪 · Gabriele Inghirami🇩🇪 · Hannah Elfner🇩🇪 · Luciano Rezzolla🇩🇪 · Dirk H. Rischke🇩🇪

   We present BHAC-QGP, a new numerical code to simulate the evolution of matter created in heavy-ion collisions in the presence of electromagnetic fields. It is derived from the Black Hole Accretion Code (BHAC), which has been designed to model astrophysical processes in a general-relativistic magnetohydrodynamical description. As the original Black Hole Accretion Code, BHAC-QGP benefits from the use of Adaptive Mesh Refinement (AMR), which allows us to dynamically adjust the resolution where necessary, and makes use of time-dependent Milne coordinates and the ultrarelativistic equation of state, $P=e/3$. We demonstrate that BHAC-QGP accurately passes a number of systematic and rigorous tests.

   hep-phnucl-thPRC(2025)·10 citations
10. 10*

    BHAC-QGP: three-dimensional MHD simulations of relativistic heavy-ion collisions, II. Application to Au-Au collisions

    Markus Mayer🇩🇪 · Ashutosh Dash🇩🇪 · Gabriele Inghirami🇩🇪 · Hannah Elfner🇩🇪 · Luciano Rezzolla🇩🇪 · Dirk H. Rischke🇩🇪

    We present BHAC-QGP, a new numerical code to simulate the evolution of matter created in heavy-ion collisions. BHAC-QGP is based on the Black Hole Accretion Code (BHAC), which has been designed to model astrophysical processes through the solution of the equations of general-relativistic magnetohydrodynamics. Like the mother code, BHAC-QGP uses Adaptive Mesh Refinement (AMR), which allows for a dynamic adjustment of the resolution in regions of the computational domain where a particularly high accuracy is needed. We here discuss a number of applications of BHAC-QGP to Au-Au collisions at Relativistic Heavy-Ion Collider (RHIC) energies and show that the code is able to reproduce results of other simulations of these scenarios, but with much higher accuracy.

    hep-phnucl-thPRC(2025)·20 citations
11. 11*

    Axi-Majoron : One-shot solution to most of the big puzzles of particle cosmology

    Gabriela Barenboim🇪🇸 · Pyungwon Ko🇰🇷 · Wan-il Park🇰🇷

    The details of the minimal cosmological standard model (MCSM) proposed in [arXiv:2403.05390.] are discussed. The model is based on the scale-symmetry and the global Peccei-Quinn(PQ) symmetry with a key assumption that the latter is broken only in the gravity sector in a scale-invariant manner. We show that the model provides a quite simple unified framework for the unknown history of the Universe from inflation to the epoch of big-bang nucleosynthesis, simultaneously addressing key puzzles of high energy theory and cosmology: (i) the origin of scales, (ii) primordial inflation, (iii) matter-antimatter asymmetry, (iv) tiny neutrino masses, (v) dark matter, and (vi) the strong \textit{CP}-problem. Scale symmetry can be exact, and the Planck scale is dynamically generated. The presence of Gauss-Bonnet term may safely retain dangerous nonperturbative symmetry-breaking effects negligible, allowing a large-field trans-Planckian inflation along the PQ-field. Isocurvature perturbations of axi-Majorons are suppressed. A sizable amount of PQ-number asymmetry is generated at the end of inflation, and conserved afterwards. Domain wall problem is absent due to the nonrestoration of the symmetry and the nonzero PQ-number asymmetry. Baryogenesis can be realized by either the transfer of the PQ-number asymmetry through the seesaw sector, or by resonant leptogenesis. Dark matter is purely cold axi-Majorons from the mis-alignment contribution with the symmetry-breaking scale of $\mathcal{O}(10^{12})\mathrm{GeV}$. Hot axi-Majorons from the decay of the inflaton become a natural source for a sizable amount of dark radiation. Inflationary gravitational waves have information about the mass parameters of the lightest left-handed and right-handed neutrinos, thanks to the presence of an early matter-domination era driven by the long-lived lightest right-handed neutrino species.

    hep-phgr-qcPRD(2024)·8 citations
12. 12*

    An Algorithm to Parallelise Parton Showers on a GPU

    Michael H. Seymour🇬🇧 · Siddharth Sule🇬🇧

    The Single Instruction, Multiple Thread (SIMT) paradigm of GPU programming does not support the branching nature of a parton shower algorithm by definition. However, modern GPUs are designed to schedule threads with diverging processes independently, allowing them to handle such branches. With regular thread synchronisation and careful treatment of the individual steps, one can simulate a parton shower on a GPU. We present a Sudakov veto algorithm designed to simulate parton branching on multiple events in parallel. We also release a CUDA C++ program that generates matrix elements, showers partons and computes jet rates and event shapes for LEP at 91.2 GeV on a GPU. To benchmark its performance, we also provide a near-identical C++ program designed to simulate events serially on a CPU. While the consequences of branching are not absent, we demonstrate that a GPU can provide the throughput of a many-core CPU. As an example, we show that the time taken to shower 10^6 events on one NVIDIA TESLA V100 GPU is equivalent to that of 295 Intel Xeon E5-2620 CPU cores.

    hep-phSciPost Phys.Codeb.(2024)·8 citations
13. 13*

    Interpreting 95 GeV di-photon/$b\bar{b}$ excesses as a lightest Higgs boson of the MRSSM

    Jan Kalinowski🇵🇱 · Wojciech Kotlarski🇵🇱

    The Minimal R-symmetric Supersymmetric Standard Model (MRSSM) is a well motivated BSM model which can accommodate the observed 125 GeV Higgs boson in agreement with electroweak precision observables, in particular with the $W$ boson mass and $T$ parameter. In the 2016 paper we showed that the SM-like 125 GeV Higgs state can be also realised as the second-to-lightest scalar of the MRSSM, leaving room for another sub-100 GeV state. Motivated by the recent ATLAS and CMS observation of the di-photon excess at a mass of around 95 GeV we investigate the possibility whether this could be the lightest CP-even MRSSM scalar in a variation of our benchmarks presented in the 2016 work. We show that such a state can also simultaneously explain the excess in the $b\bar{b}$ final state observed around the same mass value at LEP. Due to the R-symmetric nature of the model, a light singlet-like Higgs state leads necessarily to a light bino-singlino Dirac dark matter candidate, which can give a correct relic density while evading current experimental bounds. Dark matter and LHC searches place further bounds on this scenario and point to parameter regions which are viable and of interest for the LHC Run III and upcoming dark matter experiments.

    hep-phJHEP(2024)·26 citations
14. 14*

    Molecular pentaquarks with hidden charm and double strangeness

    L.Roca🇪🇸 · J.Song🇪🇸 · E.Oset🇪🇸

    We analyze theoretically the coupled-channel meson-baryon interaction with global flavor $\bar{c}cssn$ and $\bar{c}csss$, where mesons are pseudoscalars or vectors and baryons have $J^P=1/2^{+}$ or $3/2^{+}$. The aim is to explore whether the nonlinear dynamics inherent in the unitarization process within coupled channels can dynamically generate double- and triple-strange pentaquark-type states ($P_{css}$ and $P_{csss}$ respectively), for which there is no experimental evidence to date. We evaluate the s-wave scattering matrix by implementing unitarity in coupled channels, using potential kernels obtained from t-channel vector meson exchange. The required $PPV$ and $VVV$ vertices are obtained from Lagrangians derived through appropriate extensions of the local hidden gauge symmetry approach to the charm sector, while capitalizing on the symmetry of the spin and flavor wave function to evaluate the $BBV$ vertex. We find four different poles in the double strange sector, some of them degenerate in spin. For the triple-strange channel we find the meson-baryon interaction insufficient to generate a bound or resonance state through the unitary coupled-channel dynamics.

    hep-phPRD(2024)·26 citations
15. 15*

    Moments of Clarity: Streamlining Latent Spaces in Machine Learning using Moment Pooling

    Rikab Gambhir🇺🇸 · Athis Osathapan🇺🇸 · Jesse Thaler🇺🇸

    Many machine learning applications involve learning a latent representation of data, which is often high-dimensional and difficult to directly interpret. In this work, we propose "Moment Pooling", a natural extension of Deep Sets networks which drastically decrease latent space dimensionality of these networks while maintaining or even improving performance. Moment Pooling generalizes the summation in Deep Sets to arbitrary multivariate moments, which enables the model to achieve a much higher effective latent dimensionality for a fixed latent dimension. We demonstrate Moment Pooling on the collider physics task of quark/gluon jet classification by extending Energy Flow Networks (EFNs) to Moment EFNs. We find that Moment EFNs with latent dimensions as small as 1 perform similarly to ordinary EFNs with higher latent dimension. This small latent dimension allows for the internal representation to be directly visualized and interpreted, which in turn enables the learned internal jet representation to be extracted in closed form.

    hep-phcs.LGstat.MLPRD(2024)·11 citations
16. 16*

    TMDs from Semi-inclusive Energy Correlators

    Xiaohui Liu🇨🇳 · Hua Xing Zhu🇨🇳

    We introduce a novel category of observables known as the Semi-Inclusive Energy Correlators (SIECs), an extension of the recently proposed nucleon energy correlator to integrate a new element, the fragmenting energy correlation function. These SIECs gauge the correlation between the examined hadron and the surrounding radiations, providing a comprehensive tomography of the radiative patterns originating from initial state radiation or parton fragmentation. As such, they could function as the generating functions for numerous kinematic distributions. To illustrate, we find a direct relation between the transverse momentum moments (TMMs) of the transverse momentum-dependent (TMD) distributions and the SIECs. We demonstrate how the TMMs of the TMD parton distributions and the fragmentation functions can be distinctively derived from the nucleon energy correlator and the fragmenting energy correlator, respectively, without enforcing the back-to-back kinematics.

    hep-phhep-ex27 citations
17. 17*

    Search for Cosmic-ray Boosted Sub-MeV Dark-Matter-Electron Scattering in PandaX-4T

    Xiaofeng Shang · Abdusalam Abdukerim · Zihao Bo · Wei Chen · Xun Chen · Chen Cheng · Zhaokan Cheng · Xiangyi Cui · Yingjie Fan · Deqing Fang · Lisheng Geng · Karl Giboni and 79 other authors

    We report the first search for the elastic scatterings between cosmic-ray boosted sub-MeV dark matter and electrons in the PandaX-4T liquid xenon experiment. Sub-MeV dark matter particles can be accelerated by scattering with electrons in the cosmic rays and produce detectable electron recoil signals in the detector. Using the commissioning data from PandaX-4T of 0.63~tonne$\cdot$year exposure, we set new constraints on DM-electron scattering cross sections for DM masses ranging from 10~eV/$c^2$ to 3~keV/$c^2$.

    ↳ hep-exhep-phPRL(2024)·24 citations
18. 18*

    Inflation and reheating in quadratic metric-affine gravity with derivative couplings

    Ioannis D. Gialamas🇪🇪 · Theodoros Katsoulas🇬🇷 · Kyriakos Tamvakis🇬🇷

    Within the framework of metric-affine theories of gravity, where both the metric and connection are treated as independent variables, we consider actions quadratic in the Ricci scalar curvature coupled non-minimally to a scalar field through derivative couplings. Our analysis delves into the inflationary predictions, revealing their consistency with the latest observational constraints across a wide range of parameters. This compatibility permits adjustments such as an increase in the spectral index and a reduction in the tensor-to-scalar ratio. While we do not propose a specific reheating mechanism, our analysis demonstrates that within the quadratic model of inflation, the maximum reheating temperature can reach $\sim 3\times 10^{15}\mathrm{GeV}$.

    ↳ gr-qcastro-ph.COhep-phJCAP(2024)·21 citations
19. 19*

    Nuclear coherent ${\pi }^0$ photoproduction with charge-exchange and spin-flip rescattering

    Viacheslav Tsaran🇩🇪 · Marc Vanderhaeghen🇩🇪

    In this work, we present an updated model for nuclear ${\pi }^0$ photoproduction, which incorporates pion second-order rescattering on intermediate excited nuclear states. Our approach is based on the distorted wave impulse approximation in momentum space. The many-body medium effects are incorporated in the complex effective $\Delta$ self-energy, employing the results of the recently developed second-order pion-nucleus scattering potential. The experimental data for ${}^{12}$C and ${}^{40}$Ca are successfully described without the need to fit the model parameters of the photoproduction amplitude as a result of incorporating the second-order part of nuclear photoproduction potential, which involves intermediate nucleon spin-flip and charge exchange.

    ↳ nucl-thhep-phPRC(2024)·4 citations
20. 20*

    The neutron decay anomaly, neutron stars and dark matter

    Mar Bastero-Gil🇪🇸 · Teresa Huertas-Roldan🇪🇸 · Daniel Santos🇫🇷

    The discrepancies in different measurements of the lifetime of isolated neutrons could be resolved by considering an extra neutron decay channel into dark matter, with a branching ratio of the order of $O(1$\%). Although the decay channel into a dark fermion $\chi$ plus visible matter has been already experimentally excluded, a dark decay with either a scalar or dark photon remains still a possibility. In particular, a model with a fermion mass $m_{\chi }\approx 1$ GeV and a scalar $m_{\varphi }\approx O(\mathrm{MeV})$ could provide not only the required branching ratio to explain the anomaly but also a good dark matter (DM) candidate with the right thermal abundance today. Although the interaction DM-neutron will affect the formation of neutron stars, the combined effect of the dark matter self-interactions mediated by the light scalar and an effective repulsive interaction with the neutrons induced by the scalar-Higgs coupling would allow heavy enough neutron stars. The combined constraints from neutron lifetime, dark matter abundance, neutron star and Higgs physics, and Big Bang Nucleosynthesis, restrict the light scalar mass to the range $2m_e<m_{\varphi }<2m_e+0.0375$ MeV.

    ↳ astro-ph.COgr-qchep-phPRD(2024)·19 citations
21. 21*

    One-Loop Quantum Stress-Energy Tensor for the Kink and sine-Gordon Solitons

    Noah Graham🇺🇸 · Herbert Weigel🇿🇦

    We compute the renormalized one-loop quantum corrections to the energy density $T_{00}(x)$ and pressure $T_{11}(x)$ for solitons in the $1+1$ dimensional scalar sine-Gordon and kink models. We show how precise implementation of counterterms in dimensional regularization resolves previously identified discrepancies between the integral of $T_{00}(x)$ and the known correction to the total energy.

    ↳ hep-thhep-phPLB(2024)·3 citations
22. 22*

    Measuring the molecular Migdal effect with neutron scattering on diatomic gases

    Yonatan Kahn🇺🇸 · Jesús Pérez-Ríos🇺🇸

    The Migdal effect is a key inelastic signal channel which could be used to detect low-mass dark matter, but it has never been observed experimentally using Standard Model probes. Here we propose a conceptual design for an experiment which could detect the Migdal effect in diatomic molecules through low-energy neutron scattering, and we provide the requirements on the beam spectrum and reducible backgrounds such that a detection may be achieved. The enhancement of the Migdal rate through non-adiabatic couplings, which are absent in isolated atoms, combined with the distinctive photon energies of electronic transitions in CO, suggest that a positive detection of the molecular Migdal effect may be possible with modest beam times at existing neutron facilities.

    ↳ hep-excond-mat.quant-gashep-phphysics.atom-ph+1PRD(2024)·5 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.