Wed·Mar 15, 2023Wednesday·March 15, 2023

1. 01*

   Non-linear non-renormalization theorems

   Weiguang Cao🇯🇵 · Franz Herzog🇬🇧 · Tom Melia🇯🇵 · Jasper Roosmale Nepveu🇩🇪

   We study the mixing of operators under renormalization group flow in quantum theories, and prove a non-renormalization theorem at non-linear order. It dictates zeros up to a certain number of loops in anomalous dimension tensors that control, for example, the mixing of operators at order dimension six squared into dimension eight. We obtain new results at up to three loops for the mass dimension eight anomalous dimension tensor of ${\varphi }^4$ theory in $D=4-2\epsilon$ dimensions and verify the zeros predicted by the theorem.

   hep-phhep-thJHEP(2023)·13 citations
2. 02*

   Mass Spectrum, Root Mean Square Radii, Form Factors and Charge Radii of Mesons

   Nosheen Akbar🇵🇰 · Bushra Shafaq🇵🇰 · Sarwat Zahra🇵🇰 · Amna Mir🇵🇰

   In this work, properties of charmonium, bottomonium and charmed-bottom mesons for S, P, D states are calculated with the selection of suitable trial wave functions for the non-relativistic potential model along with the incorporation of spin interactions. These trial wave functions are tested by calculating the masses of ground, radial and orbital excited states of mesons with the variational method. The mass predictions show good agreement with the available experimental data and theoretical predictions found by different methods. This indicates that these trial wave functions are appropriate for further study on mesons. These trial wave functions are used to calculate RMS radii, form factors and charged radii. Results show that RMS radii and charged radii have inverse relation with the masses of mesons, i.e., heavier mesons have smaller radii and vice versa. Momentum dependence of the form factors is studied graphically.

   hep-phJ.Korean Phys.Soc.(2025)·4 citations
3. 03*

   Two-loop master integrals for a planar and a non-planar topology relevant for single top production

   Nikolaos Syrrakos🇩🇪

   We provide analytic results for two-loop four-point master integrals with one massive propagator and one massive leg relevant to single top production. Canonical bases of master integrals are constructed and the Simplified Differential Equations approach is employed for their analytic solution. The necessary boundary terms are computed in closed form in the dimensional regulator, allowing us to obtain analytic results in terms of multiple polylogarithms of arbitrary transcendental weight. We provide explicit solutions of all two-loop master integrals up to transcendental weight six and discuss their numerical evaluation for Euclidean and physical phase-space points.

   hep-phhep-thJHEP(2023)·5 citations
4. 04*

   Quark pair angular correlations in the proton: entropy versus entanglement negativity

   Adrian Dumitru🇺🇸 · Eric Kolbusz🇺🇸

   Two-particle correlations in the proton on the light-front are described by a mixed density matrix obtained by tracing over all other, unobserved, degrees of freedom. We quantify genuinely quantum quark azimuthal correlations in terms of the entanglement negativity measure of Quantum Information Theory. While the two-quark state in color space is one of high entropy and weak quantum correlation, we find that a standard three-quark model wave function from the literature predicts an azimuthally correlated state of low entropy and high entanglement negativity. Low entropy is consistent with expectations for many colors (at fixed 't Hooft coupling $g^2{N}_c$) but high negativity indicates substantial two-particle quantum correlations at $N_c=3$. Suppressing quantum correlations associated with entanglement negativity strongly modifies quark pair azimuthal moments $⟨{\zeta }^n⟩$, $\zeta =\exp (i({\varphi }_1-{\varphi }_2))$, intrinsic to the proton state. We also describe how to account for the leading $\mathcal{O}(g^2)$ correction to the density matrix from light-cone perturbation theory which is due to the presence (or exchange) of a gluon in the proton. This correction increases the entropy and reduces the negativity of the density matrix for quark pair azimuthal correlations. Hence, the entanglement negativity measure may provide novel insight into the structure of the proton state of QCD.

   hep-phquant-phPRD(2023)·13 citations
5. 05*

   The study of weak decays induced by ${\frac{1}{2}}^{+}\to {\frac{3}{2}}^{-}$ transition in light-cone sum rules

   T.M.Aliev🇹🇷 · S.Bilmis🇹🇷 · M.Savci🇹🇷

   In this study, we analyzed the weak decays induced by $J^P={\frac{1}{2}}^{+}\to {\frac{3}{2}}^{-}$ transitions within the light-cone sum rules. Specifically, semileptonic decays of the bottom baryons into the P-wave baryons ${\Lambda }_b\to {\Lambda }_c(2625)\ell {\nu }_l$ and ${\Xi }_b\to {\Xi }_c(2815)\ell {\nu }_l$ as well as nonleptonic ${\Lambda }_b\to {\Lambda }_c(2625)\pi (\rho )$ and ${\Xi }_b\to {\Xi }_c(2815)\pi (\rho )$ decays are investigated. The form factors for the considered transitions are obtained within the sum rules method. With the calculated form factors, the decay widths of the processes are determined. Up to now, only the decay width for ${\Lambda }_b^0\to {\Lambda }_c^{+}{\mu }^{-}{\nu }_{\mu }$ has been measured among the considered decays, and we observe that our finding is quite compatible with the measurement. We also compare our results with the predictions of other approaches.

   hep-phPLB(2023)·11 citations
6. 06*

   Probing Lepton Flavor Violation in Meson Decays with LHC Data

   Sébastien Descotes-Genon🇫🇷 · Darius A. Faroughy🇺🇸 · Ioannis Plakias🇫🇷 · Olcyr Sumensari🇫🇷

   In this letter, we use LHC data from the Drell-Yan processes $pp\to {\ell }_i{\ell }_j$ (with $i\ne j$) to derive model-independent upper limits on lepton-flavor-violating meson decays. Our analysis is based on an Effective Field Theory (EFT) approach and it does not require a specific assumption regarding the basis of effective operators. We find that current LHC data (140~${\mathrm{fb}}^{-1}$) already provides competitive limits on $B(B\to \pi e\tau )$ and $B(B\to \pi \mu \tau )$ with respect to the ones obtained through experimental searches at the $B$-factories. Moreover, we derive upper limits on several decays that have not been searched for experimentally yet, such as $D^0\to e\tau$ in the charm sector, and various semileptonic decays such as $B\to \rho \mu \tau$, $B_s\to K\mu \tau$ and $B_s\to \varphi \mu \tau$. Lastly, we discuss the validity of the EFT description of LHC data and the impact of loop corrections in our analysis.

   hep-phhep-exEPJC(2023)·16 citations
7. 07*

   Observational constraint on axion dark matter in a realistic halo profile with gravitational waves

   Takuya Tsutsui🇯🇵 · Atsushi Nishizawa🇯🇵

   Axions are considered as a candidate of dark matter. The axions form coherent clouds which delay and amplify gravitational waves (GWs) at a resonant frequency. That is, the coherent axion clouds produce secondary GWs following a primary wave. All GWs from compact binary mergers detected so far propagate in the Milky Way halo composed of dark matter so that such GWs are followed by the secondary GWs. Since the properties of the secondary GWs depend on the axion mass and coupling with the parity violating sector of gravity, we can search for a characteristic signal produced by axions. In our previous study, we have developed a search method optimized for the axion signals, and obtained about ten times stronger constraint on the coupling than the previous best one for the axion mass range, $[1.7\times 10^{-13},8.5\times 10^{-12}]\mathrm{eV}$. However, in our previous search, we assume that dark matter is homogeneously distributed in the Milky Way halo, which is unrealistic. In this paper, we extend the dark matter profile to a more realistic one called the core NFW profile, and find that the constraint in our previous study is robust to the dark matter profile.

   hep-phastro-ph.COgr-qcPRD(2023)·8 citations
8. 08*

   Polarized proton structure in the resonance region

   A.N. Hiller Blin🇩🇪 · V.I. Mokeev🇺🇸

   In view of the precise data available on inclusive polarized electron scattering off polarized proton targets in the nucleon resonance excitation region, we compare these results with the coherent sum of resonant contributions to the polarized structure function $g_1$ and virtual photon asymmetry $A_1$. To this goal, we employ the nucleon resonance electroexcitation amplitudes determined for photon virtualities $Q^2$ $<$ 5.0 GeV${}^2$ from analyses of the CLAS data on exclusive electroproduction off protons in the resonance region. Most of the well established resonances of four star PDG status in the mass range up to 1.75~GeV are included. We find that the resonance-like structures observed in the inclusive $g_1$ data are related to the resonant contributions in the entire range of photon virtuality $Q^2$ where the data on $g_1$ are available. In the range of invariant mass of the final hadron system $W$ $>$ 1.5 GeV, the data on the asymmetry $A_1$ are well reproduced even when accounting for resonant contributions only, especially for the larger values of $Q^2$ and energies analysed. This observation offers an interesting hint to quark-hadron duality seen in polarized inclusive electron scattering observables.

   hep-phhep-exFew Body Syst.(2023)·0 citations
9. 09*

   Model dependence of the number of participant nucleons and observable consequences in heavy-ion collisions

   Manjunath Omana Kuttan🇩🇪 · Jan Steinheimer🇩🇪 · Kai Zhou🇩🇪 · Marcus Bleicher🇩🇪 · Horst Stoecker🇩🇪

   The centrality determination and the estimated fluctuations of number of participant nucleons $N_{part}$ in Au-Au collisions at 1.23 $A$GeV beam kinetic energy suffers from severe model dependencies. Comparing the Glauber Monte Carlo (MC) and UrQMD transport models, it is shown that $N_{part}$ is a strongly model dependant quantity. In addition, for any given centrality class, Glauber MC and UrQMD predicts drastically different $N_{part}$ distributions. The impact parameter $b$ and the number of charged particles $N_{ch}$ on the other hand are much more correlated and give an almost model independent centrality estimator. It is suggested that the total baryon number balance, from integrated rapidity distributions, can be used instead of $N_{part}$ in experiments. Preliminary HADES data show significant differences to both, UrQMD simulations and STAR data in this respect.

   hep-phnucl-thEPJC(2023)·5 citations
10. 10*

    Determination of the distribution of strong coupling constant with machine learning

    Xiao-Yun Wang🇨🇳 · Chen Dong🇨🇳 · Quanjin Wang🇨🇳

    In this work, we use the artificial neural network (ANN) method to study and predict the distribution of strong coupling constants by fitting the existing data. Our approach takes advantage of the ability of ANN to learn complex nonlinear relations and excellent generalization, and allows for a systematic treatment of the uncertainties associated with the data. To ensure the reliability of our results, we apply three evaluation indexes to evaluate the accuracy of model during training. Finally, we obtained the predicted values of the strong coupling constants at different energy scales, and compared and verified them with the existing experimental data. Our approach represents a promising way to improve the determination of the strong coupling constant at low energies, and could have important implications for future experimental and theoretical studies in quantum chromodynamics.

    hep-ph0 citations
11. 11*

    Hadronic vacuum polarization correction to the bound-electron $g$ factor

    Eugen Dizer🇩🇪 · Zoltán Harman🇩🇪

    The hadronic vacuum polarization correction to the $g$ factor of a bound electron is investigated theoretically. An effective hadronic Uehling potential obtained from measured cross sections of $e^{-}{e}^{+}$ annihilation into hadrons is employed to calculate $g$ factor corrections for low-lying hydrogenic levels. Analytical Dirac-Coulomb wave functions, as well as bound wave functions accounting for the finite nuclear radius are used. Closed formulas for the $g$ factor shift in case of a point-like nucleus are derived. In heavy ions, such effects are found to be much larger than for the free-electron $g$ factor.

    hep-phphysics.atom-phquant-phPRA(2023)·8 citations
12. 12*

    The Production of Charm Pentaquark from B meson within SU(3) Analysis

    Na Li🇨🇳 · Ye Xing🇨🇳 · Xiao-Hui Hu🇨🇳

    We study the masses and production modes of pentaquark with the quark constituent $c\bar{q}qqq$, by the tridiquark-diquark model and systematical light flavor quark symmetry SU(3) analysis. The mass splittings show that the S-wave singly charm pentaquark $c\bar{u}dds$, $c\bar{d}usu$, $c\bar{s}udu$, and $c\bar{s}udd$ are below their strong decay thresholds, while $c\bar{u}dss,c\bar{d}uss$ with parity ${\frac{1}{2}}^{-}$ are near their strong decay thresholds, which imply the possibility of stable states. Furthermore, we discuss the production of the concerned 15 states from $B$ meson, the analysis within SU(3) symmetry yields the golden channels of production process, ${\overline{B}}_s^0\to F_{-1/2}^{+}\overline{p},B^{-}\to F_{-3/2}^{-}{\overline{\Lambda }}^0$, which expected to be work worthily in b-factory.

    hep-phEPJC(2023)·8 citations
13. 13*

    Thermal Energy of a Charm-meson Molecule in a Pion Gas

    Eric Braaten🇺🇸 · Li-Ping He🇩🇪 · Kevin Ingles🇺🇸 · Jun Jiang🇨🇳

    The thermal corrections to the propagator of a loosely bound charm-meson molecule in a pion gas are calculated to next-to-leading order in the heavy-meson expansion using a zero-range effective field theory. Ultraviolet divergences in the charm-meson-pair self energy are canceled by corrections to the charm-meson-pair contact vertex. Terms that are singular at the charm-meson-pair threshold can be absorbed into thermal corrections to the rest energies and kinetic masses of the charm-meson constituents. The remaining terms reduce to a thermal correction to the binding momentum that is proportional to the pion number density and suppressed by the pion/charm-meson mass ratio. The correction gives a tiny decrease in the binding energy of the charm-meson molecule relative to the charm-meson-pair threshold in the pion gas and a change in its thermal width that is small compared to the thermal widths of the charm-meson constituents. These results are encouraging for the prospects of observing $X(3872)$ and $T_{cc}^{+}(3875)$ in the expanding hadron gas produced by heavy-ion collisions.

    hep-phJHEP(2024)·10 citations
14. 14*

    Tau Polarization and Correlated Decays in Neutrino Experiments

    Joshua Isaacson🇺🇸 · Stefan Höche🇺🇸 · Frank Siegert🇩🇪 · Sherry Wang🇺🇸

    We present the first fully differential predictions for tau neutrino scattering in the energy region relevant to the DUNE experiment, including all spin correlations and all tau lepton decay channels. The calculation is performed using a generic interface between the neutrino event generator Achilles and the publicly available, general-purpose collider event simulation framework Sherpa.

    hep-phPRD(2023)·11 citations
15. 15*

    Probing cold nuclear matter with energy correlators

    Kyle Devereaux🇺🇸 · Wenqing Fan🇺🇸 · Weiyao Ke🇺🇸 · Kyle Lee🇺🇸 · Ian Moult🇺🇸

    The future electron-ion collider (EIC) will produce the first-ever high energy collisions between electrons and a wide range of nuclei, opening a new era in the study of cold nuclear matter. Quarks and gluons produced in these collisions will propagate through the dense nuclear matter of nuclei, imprinting its structure into subtle correlations in the energy flux of final state hadrons. In this article, we apply recent developments from the field of jet substructure, namely the energy correlator observables, to decode these correlations and provide a new window into nuclear structure. The energy correlators provide a calibrated probe of the scale dependence of vacuum quantum chromodynamics (QCD), enabling medium modifications to be imaged and interpreted as a function of scale. Using the eHIJING parton shower to simulate electron-nucleus collisions, we demonstrate that the size of the nucleus is imprinted as an angular scale in the correlators, with a magnitude that is visible for realistic EIC kinematics. We can observe the size difference between the proposed EIC nuclear targets ${}^3$He, ${}^4$He, ${}^{12}$C, ${}^{40}$Ca, ${}^{64}$Cu, ${}^{197}$Au, and ${}^{238}$U, showing that the energy correlators can image femtometer length scales using asymptotic energy flux. Our approach offers a unified view of jet substructure across collider experiments, and provides numerous new theoretical tools to unravel the complex dynamics of QCD in extreme environments, both hot and cold.

    hep-phhep-exnucl-exnucl-thPRC(2025)·55 citations
16. 16*

    The electron-proton bound state in the continuum with the positive binding energy of 1.531 of the electron mass

    A.I. Agafonov🇷🇺

    In the bound states in the continuum (BIC) the binding energy is positive, and the mass of a composite particle is greater than the total mass of its constituents. In this work the BIC state is studied for the electron-proton system with using the ladder Bethe-Salpeter equation. We demonstrate that there are two momentum space regions in which the electromagnetic interaction between the particles is strongly enhanced, and the effective coupling constant is equal to $\alpha \sqrt{m_p/m_e}=0.313$, where $\alpha$ is the fine structure constant, $m_p$ and $m_e$ are the proton and the electron masses. This interaction resonance causes the confinement of the pair in the BIC state with the positive binding energy of 1.531 of the electron mass. The integral equation for the bispinor wave function is derived. This normalized wave function which must be complex, was found numerically in the momentum and coordinate spaces. It turned out that in the BIC state, the average radius for the electron is equal to 48Fm, and the average radius for the proton is equal to 1.1Fm. This composite particle can exist exclusively in the free state, in which its properties, such as its form-factors, should only be studied. In bound states with other particles, the composite loses its individuality.

    hep-phhep-thLHEP(2023)·0 citations
17. 17*

    CMB and Lyman-$\alpha$ constraints on dark matter decays to photons

    Francesco Capozzi🇮🇹 · Ricardo Z. Ferreira🇪🇸 · Laura Lopez-Honorez🇧🇪 · Olga Mena🇪🇸

    Dark matter energy injection in the early universe modifies both the ionization history and the temperature of the intergalactic medium. In this work, we improve the CMB bounds on sub-keV dark matter and extend previous bounds from Lyman-$\alpha$ observations to the same mass range, resulting in new and competitive constraints on axion-like particles (ALPs) decaying into two photons. The limits depend on the underlying reionization history, here accounted self-consistently by our modified version of the publicly available {\tt DarkHistory} and {\tt CLASS} codes. Future measurements such as the ones from the CMB-S4 experiment may play a crucial, leading role in the search for this type of light dark matter candidates.

    ↳ astro-ph.COhep-phJCAP(2023)·52 citations
18. 18*

    Operational realization of quantum vacuum ambiguities

    Álvaro Álvarez-Domínguez🇪🇸 · José A. R. Cembranos🇪🇸 · Luis J. Garay🇪🇸 · Mercedes Martín-Benito🇪🇸 · Álvaro Parra-López🇪🇸 · Jose M. Sánchez Velázquez🇪🇸

    We provide a reinterpretation of the quantum vacuum ambiguities that one encounters when studying particle creation phenomena due to an external and time-dependent agent. We propose a measurement-motivated understanding: Each way of measuring the number of created particles selects a particular vacuum. This point of view gives a clear and physical meaning to the time evolution of the number of particles produced by the agent as the counts in a specific detector and, at the same time relates commonly used quantization prescriptions to particular measurement setups.

    ↳ hep-thgr-qchep-phPRD(2023)·11 citations
19. 19*

    The improved saturation model in nuclei

    G.R.Boroun🇮🇷 · B.Rezaei🇮🇷

    We consider the nuclear shadowing in deep-inelastic scattering corresponding to kinematic regions accessible by future experiments at electron-ion colliders. The gluon distribution at small $x$ is obtained using an improved dipole model depended on the impact parameter for atomic nucleus and compared with nCETQ15 parametrization group. The nuclear shadowing at small $x$ is defined within the color dipole formalism with respect to the mass number $A$. Its behavior is predicted for light nuclei in a wide range of the impact parameter $b$ and the transverse dipole size $r$. The nuclear saturation at large-$r$ (small ${\mu }^2$) is observable. The behavior of the nuclear ratio ${\sigma }_{\mathrm{dip}}^A/{\sigma }_0$ is similar to the Golec-Biernat-W$\ddot{\mathrm{u}}$sthoff (GBW) model in a wide range of $r$ for light and heavy nuclei at small $x$.

    ↳ nucl-thhep-phPramana(2024)·7 citations
20. 20*

    Investigate the $\Lambda$ and $\bar{\Lambda }$ polarization splitting effect with combined mechanisms

    Simin Wu🇨🇳 · Yilong Xie🇨🇳

    The significant splitting of $\Lambda$ and $\bar{\Lambda }$ polarization measured in STAR's Au+Au 7.7GeV collisions seems to be huge and unable to be described satisfactorily by any single mechanism, thus we revisit and combine there different mechanisms together on the basis of our PICR hydrodynamic model, to explain the experimental data. The three mechanisms, i.e. the meson field mechanism, the freeze-out space-time mechanism, and the QGP's magnetic field mechanism, lie on different stage of high energy collisions, and thus are not contradicted with each other. We find that the meson field mechanism is dominat, while the QGP's magnetic field mechanism is rather trivial, and freeze-out time effect is restricted by the small FZ time difference, leading to a hierarchy of $\Delta P_J\gg \Delta P_t\gg \Delta P_m$. Besides, the combination of different mechanisms could promote the mean value of polarization splitting from about 3\%-4\% to 4.5\%, which is more close to the experimental measured mean value of 5.8\%.

    ↳ nucl-thhep-phEPJA(2023)·4 citations
21. 21*

    Primordial black hole formation during the QCD phase transition: threshold, mass distribution and abundance

    Ilia Musco🇮🇹 · Karsten Jedamzik🇫🇷 · Sam Young🇳🇱

    Primordial black hole (PBH) formation during cosmic phase transitions and annihilation periods, such as the QCD transition or the $e^{+}{e}^{-}$-annihilation, is thought to be particularly efficient due to a softening of the equation of state. We present a detailed numerical study of PBH formation during the QCD epoch in order to derive an accurate PBH mass function. We also briefly consider PBH formation during the $e^{+}{e}^{-}$-annihilation epoch. Our investigation confirms that, for nearly scale-invariant spectra, PBH abundances on the QCD scale are enhanced by a factor $\sim 10^3$ compared to a purely radiation dominated Universe. For a power spectrum producing an (almost) scale-invariant PBH mass function outside of the transition, we find a peak mass of $M_{\mathrm{pbh}}\approx 1.9M_{\odot }$ with a fraction $f\approx 1.5\times 10^{-2}$ of the PBHs having a mass of $M_{\mathrm{pbh}}>10M_{\odot }$, possibly contributing to the LIGO-Virgo black hole merger detections. We point out that the physics of PBH formation during the $e^{+}{e}^{-}$-annihilation epoch is more complex as it is very close to the epoch of neutrino decoupling. We argue that neutrinos free-streaming out of overdense regions may actually hinder PBH formation.

    ↳ astro-ph.COgr-qchep-phPRD(2024)·87 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.