Tue·Apr 5, 2022Tuesday·April 5, 2022

1. 01*

   Data-driven extraction of the substructure of quark and gluon jets in proton-proton and heavy-ion collisions

   Yueyang Ying🇺🇸 · Jasmine Brewer🇨🇭 · Yi Chen🇺🇸 · Yen-Jie Lee🇺🇸

   The different modifications of quark- and gluon-initiated jets in the quark-gluon plasma (QGP) produced in heavy-ion collisions is a long-standing question that has not yet received a definitive answer from experiments. In particular, the relative sizes of the modification of quark and gluon jets differ between theoretical models. Therefore, a fully data-driven technique is crucial for an unbiased extraction of the quark and gluon jet spectra and substructure. We perform a proof-of-concept study based on proton-proton and heavy-ion collision events from the \textsc{Pyquen} generator with statistics accessible in Run 4 of the Large Hadron Collider. We use a statistical technique called topic modeling to separate quark and gluon contributions to jet observables. We demonstrate that jet substructure observables, such as the jet shape and jet fragmentation function, can be extracted using this data-driven method. These values can then be used to obtain the modification of quark and gluon jet substructures in the QGP. We also perform the topic separation on smeared input data to demonstrate that the approach is robust to fluctuations arising from a QGP background. These results suggest the potential for an experimental determination of quark and gluon jet spectra and their substructure.

   hep-ph11 citations
2. 02*

   NNLO event generation for $\mathbf{pp}\to \mathbf{Zh}\to {\mathbf{\ell }}^{+}{\mathbf{\ell }}^{-}\mathbf{b}\bar{\mathbf{b}}$ production in the SM effective field theory

   Ulrich Haisch🇩🇪 · Darren J. Scott🇩🇪 · Marius Wiesemann🇩🇪 · Giulia Zanderighi🇩🇪 · Silvia Zanoli🇩🇪

   We consider associated $Zh$ production with $Z\to {\ell }^{+}{\ell }^{-}$ and $h\to b\bar{b}$ decays in hadronic collisions. In the framework of the Standard Model effective field theory (SMEFT) we calculate the QCD corrections to this process and achieve next-to-next-to-leading order plus parton shower (NNLO$+$PS) accuracy using the MiNNLO${}_{\mathrm{PS}}$ method. This precision is obtained for a subset of six SMEFT operators, including the corrections from effective Yukawa- and chromomagnetic dipole-type interactions. Missing higher-order QCD effects associated with the considered dimension-six operators are estimated to have a relative numerical impact of less than a percent on the total rate once existing experimental limits on the relevant Wilson coefficients are taken into account. We provide a dedicated Monte Carlo (MC) code that evaluates the NNLO SMEFT corrections on-the-fly in the event generation. This MC generator is used to study the numerical impact of NNLO$+$PS corrections on the kinematic distributions in $pp\to Zh\to {\ell }^{+}{\ell }^{-}b\bar{b}$ production employing simple SMEFT benchmark scenarios. We identify the invariant mass $m_{b\bar{b}}$ of the two $b$-tagged jets as well as the three-invariant jet mass $m_{b\bar{b}j}$ as particularly interesting observables to study SMEFT effects. These distributions receive contributions that change both their normalisation and shape with the latter modifications depending on the exact jet definition. To our knowledge SMEFT effects of this type have so far not been discussed in the literature. The presented MC generator can also serve as a starting point to obtain NNLO$+$PS accuracy for a suitable enlarged set of effective operators in the future.

   hep-phhep-exJHEP(2022)·41 citations
3. 03*

   Weak decays of triply heavy baryons in the light-front approach

   Zhen-Xing Zhao · Qi Yang

   In this work, we investigate the weak decays of ground-state triply heavy baryons. We first obtain the form factors using the light-front quark model in the three-quark picture, and then apply them to arrive at some phenomenological predictions, including the decay widths of semileptonic decays and nonleptonic decays. Our results are expected to be helpful for the experimental search for triply heavy baryons.

   hep-phEPJC(2025)·19 citations
4. 04*

   Gravitational-Wave Signatures of Chiral-Symmetric Technicolor

   Hao Yang🇨🇳 · Felipe F. Freitas🇵🇹 · Antonino Marciano🇨🇳 · António P. Morais🇵🇹 · Roman Pasechnik🇸🇪 · João Viana🇵🇹

   A chiral-symmetric technicolor model successfully reconciles the tension between electroweak precision tests and traditional technicolor models. Focusing on its simplest realization preserving the conventional Higgs mechanism, we study its primordial gravitational wave signatures originating from first order phase transitions in the early Universe. We found that abundant phase transition patterns arise from a physically viable parameter space. Besides, we have also found gravitational wave signals possibly visible by future experiments, such as LISA, BBO and u-DECIGO. Our results stress the importance of gravitational wave detectors in exploring new physics complementary to ground colliders in the multi-messenger astronomy era.

   hep-phgr-qchep-thPLB(2022)·6 citations
5. 05*

   Naturally small Yukawa couplings from trans-Planckian asymptotic safety

   Kamila Kowalska🇵🇱 · Soumita Pramanick🇵🇱 · Enrico Maria Sessolo🇵🇱

   In gauge-Yukawa systems embedded in the framework of trans-Planckian asymptotic safety we discuss the dynamical generation of arbitrarily small Yukawa couplings driven by the presence of a non-interactive infrared-attractive fixed point in the renormalization group flow. Additional ultraviolet-attractive fixed points guarantee that the theory remains well defined up to an infinitely high scale. We apply this mechanism to the Yukawa couplings of the Standard Model extended with right-handed neutrinos, finding that asymptotically safe solutions in agreement with the current experimental determination of the masses and mixing angles exist for Dirac neutrinos with normal mass ordering. We generalize the discussion by applying the same mechanism to a new-physics model with sterile-neutrino dark matter, where we generate naturally the feeble Yukawa interaction required to reproduce via freeze-in the correct relic abundance.

   hep-phJHEP(2022)·39 citations
6. 06*

   Dilepton production from chirally asymmetric matter

   Nilanjan Chaudhuri🇮🇳 · Snigdha Ghosh🇮🇳 · Sourav Sarkar🇮🇳 · Pradip Roy🇮🇳

   We evaluate the dilepton production rate (DPR) from hot and dense chirally asymmetric quark matter. The presence of a finite chiral chemical potential (CCP) in the electromagnetic spectral function results in the appearance of new cut structures signifying additional scattering processes in the medium which leads to a significant enhancement in the DPR at lower values of invariant mass. The constituent quark mass evaluated using a 3-flavour Nambu--Jona-Lasinio model is also non-trivially affected by the CCP. These are found to result in a continuous dilepton production rate as a function of the invariant mass for higher values of temperature and baryonic chemical potential.

   hep-phnucl-thPRD(2022)·6 citations
7. 07*

   Charmonium tetraquarks and pentaquarks or an additional quark?

   Scott Chapman🇺🇸

   Most of the exotic hadrons discovered over the last 20 years fit into the quark model as normal mesons and baryons if the existence of a seventh flavor of quark is hypothesized. If the quark has a mass of $\sim$2.9 GeV, a charge of $-\frac{1}{3}$, and light-scalar-mediated decays to other quarks and $c\bar{c}$, then it is able to reproduce the mass, spin, parity, production and decay modes of most observed exotic hadrons. Predictions are made for additional hadrons as well as new production and decay modes for observed exotic hadrons.

   hep-ph2 citations
8. 08*

   Time evolution of the lepton number of Majorana neutrinos in the Schrödinger picture versus Heisenberg picture

   Nicholas J. Benoit🇯🇵 · Yuta Kawamura🇯🇵 · Takuya Morozumi🇯🇵

   In this paper, we study the time evolution of the expectation value of Majorana neutrino with the Schrödinger picture.The operators with the definite lepton number and operators with the definite mass are related to each other by a Bogolyubov transformation. Then the vacuum with the null lepton number is also related to the vacuum for the massive operator and it is written by the superposition of the vacuum for massive field and Majorana pairs condensed states. We choose the state with a definite lepton number $L$ $=1$ and the momentum $\mathbf{q}\ne 0$ as an initial state. By writing the state in terms of the superposition of energy eigenstates, we are able to study the time evolution of the state in the Schrödinger picture.The expectation value of lepton number operator is computed and it reproduces the same result as that obtained in the corresponding Heisenberg operator.

   hep-phPoS(2022)·2 citations
9. 09*

   An Alternative Framework for E-Model Inflation in Supergravity

   C. Pallis🇬🇷

   We present novel realizations of E-model inflation within Supergravity which are largely associated with the existence of a pole of order one in the kinetic term of the (gauge-singlet) inflaton superfield. This pole arises due to the selected logarithmic Kahler potentials K1 and ~K1, which parameterize the same hyperbolic manifold with scalar curvature R=-2/N, where N>0 is the coefficient of a logarithmic term. The associated superpotential W exhibits the same R charge with the inflaton-accompanying superfield and includes all the allowed renormalizable terms. For K=K1, inflation can be attained for N=2 at the cost of some tuning regarding the coefficients of the W terms and predicts a tensor-to-scalar ratio r at the level of 0.001. The tuning can be totally eluded for K=~K1, which allows for quadratic- and quartic-like models with N values increasing with r and spectral index ns close or even equal to its present central observational value.

   hep-phastro-ph.COhep-thEPJC(2022)·11 citations
10. 10*

    Non-thermal dark matter production and leptogenesis in a $L_{\mu }-L_{\tau }$ model

    XinXin Qi🇨🇳 · Hao Sun🇨🇳

    We discuss the possibility of light scalar dark matter generated by right-handed neutrino in a $L_{\mu }-L_{\tau }$ model, in which the dark matter ${\varphi }_{dm}$ carries $U(1{)}_{L_{\mu }-L_{\tau }}$ charge but it is a singlet in the Standard Model. We discuss the case that dark matter production mainly comes from scattering associated with a pair of right-handed neutrinos non-thermally while other related processes are highly suppressed. A feasible parameter space is considered and we found the correct dark matter relic density can be obtained without influencing the result of leptogenesis result. The heavier right-handed neutrino will induce colder dark matter production and the allowed dark matter mass region is $[10^{-5}\mathrm{GeV},0.1\mathrm{GeV}]$.

    hep-phPRD(2025)·3 citations
11. 11*

    Final bound-state formation effect on dark matter annihilation

    Xinyu Wang🇨🇳 · Fucheng Zhong🇨🇳 · Feng Luo🇨🇳

    If the annihilation products of dark matter (DM) are non-relativistic and couples directly to a light force mediator, the non-perturbation effect like final state bound state (FBS) formation and final state Sommerfeld (FSS) effect must be considered. Non-relativistic region of final particles will appear when there is small mass split between DM and products, so we study those effects in the degenerate region of mass (including kinematics forbidden case) using two specific models. We demonstrate that FBS effect will significantly modify the DM relic abundance comparing to the standard perturbation calculation in some mass split region. We emphasize that FBS effect is comparable to the FSS effect in those mass split. The conservation angular momentum are subtle considering FBS formation, in some cases there may be not $s$-wave, so we use two models exhibit the different partial wave FBS effect contribution. We also show that the FBS formation with vector boson emission process also contributes in DM relic abundance, and first calculate the $p$-wave FSS effect in the specific model.

    hep-phCPC(2022)·3 citations
12. 12*

    Study of $B_{(s)}^0\to \varphi \varphi \to (K^{+}{K}^{-})(K^{+}{K}^{-})$ decays in the perturbative QCD approach

    Da-Cheng Yan🇨🇳 · Zhou Rui🇨🇳 · Zhen-Jun Xiao🇨🇳 · Ya Li🇨🇳

    In this work, we make a detailed analysis on the penguin-dominant processes $B_{(s)}^0\to \varphi \varphi \to (K^{+}{K}^{-})(K^{+}{K}^{-})$ in the perturbative QCD (PQCD) approach. In addition to the dominant $P$-wave resonance, the scalar background $f_0(980)\to K^{+}{K}^{-}$ is also accounted for. We improve the Gegenbauer moments in $KK$ two-meson distribution amplitudes by fitting the PQCD factorization formulas to measured branching ratios of three-body and four-body $B$ decays. We extract the branching ratios of two-body $B_{(s)}^0\to \varphi \varphi$ decays from the corresponding four-body decay modes and calculate the relevant polarization fractions together with two relative phases ${\varphi }_{\parallel ,\perp }$, which are consistent with the previous theoretical predictions. The PQCD predictions for the "true" triple product asymmetries (TPAs) are zero which are expected in the standard model due to the vanishing weak phase difference, and support the current data reported by the CDF and LHCb Collaborations. A large "fake" TPA ${\mathcal{A}}_{\text{T-fake}}^1=30.4\%$ of the decay $B_s^0\to \varphi \varphi \to (K^{+}{K}^{-})(K^{+}{K}^{-})$ is predicted for the first time, which indicates the presence of the significant final-state interactions. The TPAs of the rare decay channel $B^0\to \varphi \varphi \to (K^{+}{K}^{-})(K^{+}{K}^{-})$ are also predicted and can be tested in the near future.

    hep-phPRD(2022)·14 citations
13. 13*

    Large signal of $h\to \mu \tau$ within the constraints of $e_i\to e_j\gamma$ decays in the 3-3-1 model with neutral leptons

    H.T. Hung🇻🇳 · D.T. Binh🇻🇳 · H.V. Quyet🇻🇳

    In the framework of the 3-3-1 model with neutral leptons, we have investigated the lepton-flavor-violating sources based on the Higgs mass spectrum which has two neutral Higgses identitied with corresponding ones in the Two-Higgs-Doublet model (THDM). On the $13\mathrm{TeV}$ scale of the LHC, we point out the parameter space regions where the experimental limits of $e_i\to e_j\gamma$ decays are satisfied. These regions depend heavily on the mixing of exotic leptons but are predicted to have large $h_1^0\to \mu \tau$ signals. We also show that $\mathrm{Br}(h_1^0\to \mu \tau )$ can reach a value of $10^{-4}$.

    hep-phCPC(2022)·5 citations
14. 14*

    Masses and Thermodynamic Quantities of Quarkonia in Nonrelativistic Quark Model

    C. Aydın

    The temperature dependent energy, mass and some of thermodynamic quantities of charmonium and bottomonium have been calculated by solving the radial Schrödinger equation with the extended Cornell potential at finite temperature using the Nikiforov-Uvarov method. Obtained results accord with experimental data and theoretical results of the previous studies. We have found the spectrum of quarkonia mass strictly decreases at high values of temperature.

    hep-phTWMS J. Pure Appl. Math.(2023)·1 citation
15. 15*

    On dark radiation from string moduli decay to ALPs

    Howard Baer🇺🇸 · Vernon Barger🇺🇸 · Robert Wiley Deal🇺🇸

    We examine the issue of dark radiation (DR) from string moduli decay into axion-like particles (ALPs). In KKLT-type models of moduli stabilization, the axionlike phases of moduli fields are expected to decouple whilst in LVS-type moduli stabilization some can remain light and may constitute dark radiation. We evaluate modulus decay to Minimal Supersymmetric Standard Model (MSSM) particles and dark radiation for more general compactifications. In spite of tightening error bars on \Delta N_{eff}, we find only mild constraints on modulus-ALP couplings due to the somewhat suppressed modulus branching fraction to DR owing to the large number of MSSM decay modes. We anticipate that future CMB experiments with greater precision on \Delta N_{eff} may still turn up evidence for DR if the ALP associated with the lightest modulus field is indeed light.

    hep-phastro-ph.COJHEAp(2022)·14 citations
16. 16*

    Multiple Charged Meson Production in Exclusive $B_c$ Decays: $K+4\pi ,$$KK+3\pi$, $7\pi$ Cases

    A. V. Luchinsky🇷🇺

    Theoretical analysis of three exclusive decays, $B_c\to J/\psi +\mathcal{R},$where $\mathcal{R}=K+4\pi ,$$KK+3\pi$, or $7\pi$, is given. Using the factorization method and the resonance approximation (methods proved to be very useful in the analysis of some other similar decays), we have obtained analytical expressions of the required amplitudes and created distributions over some interesting mass combinations. Presented results could be used for comparison with forthcoming experimental data and better understanding of the nature of heavy quarkonia.

    hep-phPLB(2022)·5 citations
17. 17*

    Neutrino Condensate Dark Energy from TeV Scale Extra Dimensions

    Ujjal Kumar Dey🇮🇳 · Utpal Sarkar🇮🇳

    We propose a new scenario of incorporating neutrino masses in models of TeV scale gravity and large extra dimensions, which can explain the dark energy problem through formation of neutrino condensates. The smallness of the neutrino masses and the scale of dark energy is protected to be small by the lepton number symmetry, which is broken in a distant brane, such that all lepton number violating effects are suppressed by the distance factor in the extra dimensions. The interactions of any bulk scalar particles are also suppressed by the distance factor. A lepton number violating soft-term is also induced from the distant brane, providing us a light pseudo-Nambu-Goldstone boson which becomes the mediator of the attractive force that forms the condensates.

    hep-phNPB(2022)·1 citation
18. 18*

    Inclusive jet and hadron suppression in a multistage approach

    A. Kumar🇨🇦 · Y. Tachibana🇯🇵 · C. Sirimanna🇺🇸 · G. Vujanovic🇺🇸 · S. Cao🇨🇳 · A. Majumder🇺🇸 · Y. Chen🇺🇸 · L. Du🇨🇦 · R. Ehlers🇺🇸 · D. Everett🇺🇸 · W. Fan🇺🇸 · Y. He🇨🇳 and 48 other authors

    We present a new study of jet interactions in the quark-gluon plasma created in high-energy heavy-ion collisions, using a multistage event generator within the JETSCAPE framework. We focus on medium-induced modifications in the rate of inclusive jets and high transverse momentum (high-$p_{\mathrm{T}}$) hadrons. Scattering-induced jet energy loss is calculated in two stages: A high virtuality stage based on the MATTER model, in which scattering of highly virtual partons modifies the vacuum radiation pattern, and a second stage at lower jet virtuality based on the LBT model, in which leading partons gain and lose virtuality by scattering and radiation. Coherence effects that reduce the medium-induced emission rate in the MATTER phase are also included. The TRENTo model is used for initial conditions, and the (2+1)dimensional VISHNU model is used for viscous hydrodynamic evolution. Jet interactions with the medium are modeled via 2-to-2 scattering with Debye screened potentials, in which the recoiling partons are tracked, hadronized, and included in the jet clustering. Holes left in the medium are also tracked and subtracted to conserve transverse momentum. Calculations of the nuclear modification factor ($R_{\mathrm{AA}}$) for inclusive jets and high-$p_{\mathrm{T}}$ hadrons are compared to experimental measurements at the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC). Within this framework, we find that with one extra parameter which codifies the transition between stages of jet modification -- along with the typical parameters such as the coupling in the medium, the start and stop criteria etc. -- we can describe these data at all energies for central and semicentral collisions without a rescaling of the jet transport coefficient $\hat{q}$.

    hep-phnucl-thPRC(2023)·88 citations
19. 19*

    Neutrino electromagnetic properties in a Leptoquark model

    R. Sánchez-Vélez🇲🇽

    The neutrino magnetic dipole moment is studied in a simple extension of the SM augmented with a scalar Leptoquark with quantum numbers $(\bar{3},1,1/3)$. In order to reach a sizeable neutrino magnetic moment, we include in the framework the contribution of right-handed neutrinos and analytical result for the one-loop contribution of a scalar LQ is presented. The allowed parameter space is found through recent restrictions on the muon $(g-2)$, the $\tau \to \mu \gamma$ and the $B_c\to {\tau }^{-}\bar{\nu }$ decay. It is shown that exist a region of the parameter space where the recent anomaly reported by the XENON collaboration can be accommodated.

    hep-ph2 citations
20. 20*

    Effective treatment of U(1) gauge field and charged particles in axion inflation

    Tomohiro Fujita🇯🇵 · Jun'ya Kume🇯🇵 · Kyohei Mukaida🇯🇵 · Yuichiro Tada🇯🇵

    The axionic inflaton with the Chern-Simons coupling may generate U(1) gauge fields and charged particles simultaneously. In order to incorporate the backreaction from the charged particles on the gauge fields, we develop a procedure to obtain an equilibrium solution for the gauge fields by treating the induced current as effective electric and magnetic conductivities. Introducing mean field approximation, and numerically solving self-consistency equations, we find that the gauge field amplitudes are drastically suppressed. Interestingly, as the production becomes more efficient, the charged particles gain a larger part of the transferred energy from the inflaton and eventually dominate it. Our formalism offers a basis to connect this class of inflationary models to a rich phenomenology such as baryogenesis and magnetogenesis.

    hep-phastro-ph.COgr-qchep-thJCAP(2022)·33 citations
21. 21*

    $p_T$ dispersion of inclusive jets in high-energy nuclear collisions

    Shi-Yong Chen🇨🇳 · Jun Yan🇨🇳 · Wei Dai🇨🇳 · Ben-Wei Zhang🇨🇳 · Enke Wang🇨🇳

    In this paper, we investigate the medium modifications of $p_T$ dispersion($p_{T}D$) of inclusive jets with small radius ($R=0.2$) in Pb+Pb collisions at $\sqrt{s}=2.76$~TeV. The partonic spectrum in the initial hard scattering of elementary collisions are obtained by an event generator POWHEG+PYTHIA, which matches the next-to-leading (NLO) matrix elements with parton showering, and energy loss of fast parton traversing in hot/dense QCD medium is calculated by Monte Carlo simulation within Higher-Twist formalism of jet quenching in heavy-ion collisions. We present the model calculations of normalized $p_{T}D$ distributions for inclusive jets in p+p and Pb+Pb collisions at $\sqrt{s}=2.76$~TeV, which give nice descriptions of ALICE measurements. It is shown that the $p_{T}D$ distributions of inclusive jets in Pb+Pb are shifted to higher $p_{T}D$ region relative to that in p+p. Thus the nuclear modification factor of $p_{T}D$ distributions for inclusive jets is smaller than unity at small $p_{T}D$ region, while larger than one at large $p_{T}D$ region. This behaviour results from more uneven $p_T$ of jet constituents as well as the fraction alteration of gluon/quark initiated jets in heavy-ion collisions. The difference of $p_{T}D$ distributions between groomed and ungroomed jets in Pb+Pb collisions are also discussed.

    hep-phCPC(2022)·10 citations
22. 22*

    Scotogenic top-quark FCNC decays

    Chuan-Hung Chen🇹🇼 · Takaaki Nomura🇨🇳

    Flavor-changing neutral current (FCNC) top-quark decays are highly suppressed due to the Glashow-Iliopoulos-Maiani mechanism in the standard model (SM). If $t\to qh,qV$ with $V=g,\gamma ,Z$ are all induced via quantum loop levels, then we investigate the effect that can enhance the top-FCNC up to the sensitivity designed at the high-luminosity (HL) LHC. Inspired by the mechanism of the scotogenic neutrino mass, we extend the SM by including $Z_2$-odd colored fermions when a $Z_2$ discrete is imposed. The results show that by taking $BR(t\to ug)\lesssim 0.61\times 10^{-4}$ recently measured by ATLAS as an input, $t\to q\gamma$ can be indirectly bounded to be $BR(t\to q\gamma )\lesssim 3.2\times 10^{-6}$, which is below the expected sensitivity at the HL LHC. After taking potential constraints from various experiments into account, the obtained branching ratios for the loop-induced $t\to qh$ and $t\to qZ$ decays can be $O(10^{-4})$, which falls within the sensitivity at the HL LHC.

    hep-phhep-exPRD(2022)·9 citations
23. 23*

    Enhanced Magnetic Quadrupole Moments in Nuclei with Octupole Deformation and their CP-violating effects in molecules

    V. V. Flambaum🇦🇺 · A. J. Mansour🇦🇺

    Nuclei with an octupole deformation have a non-zero electric octupole moment, electric dipole moment (EDM), Schiff moment and magnetic quadrupole moment (MQM) in the intrinsic frame which rotates with the nucleus. In a state with definite angular momentum in the laboratory frame, these moments are forbidden by parity (P) and time reversal invariance (T) conservation, meaning their expectation values vanish due to nuclear rotation. However, nuclei with an octupole deformation have doublets of close opposite parity rotational states with the same spin, which are mixed by T,P-odd nuclear forces. This mixing produces the orientation of the nuclear axis along nuclear spin and all moments existing in the intrinsic frame appear in the laboratory frame (provided the nuclear spin I is sufficiently large to allow such moment). Such a mechanism produces enhanced T,P-violating nuclear moments. This enhancement also takes place in nuclei with a soft octupole vibration mode. Schiff moments in such nuclei have been calculated in previous works. In the present paper we consider the magnetic quadrupole moment which appears in isotopes with nuclear spin $I\ge 1$. Magnetic interaction between the nuclear MQM and electrons produces an atomic EDM and T,P-violating nuclear spin - molecular axis interaction constants for molecules in electronic states with non-zero electron angular momentum. Measurements of these constants may be used to test CP-violation theories and search for axion dark matter in atomic, molecular and solid state experiments. Potential candidate nuclei include 153Eu, 161Dy, 221Fr, 223Fr, 223Ra, 223Rn, 225Ac, 227Ac, 229Th, 229Pa, 233U and 235U. We subsequently consider molecules containing these nuclei (EuO, EuN+, RaF, AcO, AcN+, AcF+, ThO and ThF+).

    hep-phnucl-thphysics.atom-phPRC(2022)·18 citations
24. 24*

    Structure of magnetized strange quark star in perturbative QCD

    J. Sedaghat🇮🇷 · S. M. Zebarjad🇮🇷 · G. H. Bordbar🇮🇷 · B. Eslam Panah🇮🇷

    We have performed the leading order perturbative calculation to obtain the equation of state (EoS) of the strange quark matter (SQM) at zero temperature under the magnetic field B = 10^18 G. The SQM comprises two massless quark flavors (up and down) and one massive quark flavor(strange). Consequently, we have used the obtained EoS to calculate the maximum gravitational mass and the corresponding radius of the magnetized strange quark star (SQS). We have employed two approaches, including the regular perturbation theory (RPT) and the background perturbation theory (BPT). In RPT the infrared (IR) freezing effect of the coupling constant has not been accounted for, while this effect has been included in BPT. We have obtained the value of the maximum gravitational mass to be more than three times the solar mass. The validity of isotropic structure calculations for SQS has also been investigated. Our results show that the threshold magnetic field from which an anisotropic approach begins to be significant lies in the interval 2*10^18G < B < 3*10^18G. Furthermore, we have computed the redshift, compactness and Buchdahl-Bondi bound of the SQS to show that this compact object cannot be a black hole.

    hep-phastro-ph.HEhep-thPLB(2022)·18 citations
25. 25*

    Effect of color reconnection and hadronic re-scattering on underlying events in pp collisions at LHC energies

    Krishna Kumar🇺🇸 · Sadhana Dash🇮🇳

    Underlying events dominate most of the hadronic activity in p$-$p collisions and are spanned from perturbative to non-perturbative QCD, having a sensitivity ranging from the multi-scale to very low-x scale physics. A detailed understanding of such events plays a crucial role in the accurate understanding of Standard Model ()SM and Beyond Standard Model physics. The underlying event activities has been studied within the framework of Pythia 8 Monte Carlo model, considering the underlying events observables mean charged particle multiplicity density , $⟨d^{2}N/d\eta d\varphi ⟩$ and mean scalar $p_T$ sum, $⟨d^2\sum p_T/d\eta d\varphi ⟩$ as a function of leading charged particle in towards, away, and transverse region of p$-$p collisions at $\sqrt{s}$ = 2.76, 7 and 13 TeV. The towards, away, and transverse regions have been defined on an azimuthal plane relative to leading particle in p$-$p collisions. The energy dependence of underlying events and their activities in the central and forward region has also been studied. The effect of hadronic re-scattering, color reconnection, and rope hadronization mechanism implemented in Pythia 8 has been studied in details to gain insight into the different processes contributing to underlying events in soft sector.

    hep-phEPJA(2022)·2 citations
26. 26*

    Cored Dark Matter halos in the Cosmic Neutrino Background

    Wonsub Cho🇰🇷 · Ki-Young Choi🇰🇷 · Hee Jung Kim🇰🇷

    We study the impact of the interaction between DM and the cosmic neutrino background on the evolution of galactic dark matter halos. The energy transfer from the neutrinos to the dark matter can heat the center of the galaxy and make it cored. This effect is efficient for the small galaxies such as the satellite galaxies of the Milky Way and we can put conservative constraint on the non-relativistic elastic scattering cross section as ${\sigma }_{\chi \nu }\lesssim 10^{-31}{\mathrm{cm}}^2$ for 0.1 keV dark matter and 0.1 eV neutrino.

    hep-phastro-ph.COastro-ph.GAJCAP(2023)·2 citations
27. 27*

    On the deuteron relativistic charge distributions

    Cédric Lorcé (Ecole Polytechnique, CPHT)🇫🇷 · Pierre Wang (ENSTA Paris)🇫🇷

    We study the relativistic 2D charge distributions in the case of a spin-$1$ target. These charge distributions are based on a phase-space approach allowing one to study their frame dependence, and hence to relate the familiar rest-frame picture with the light-front picture developed in the last two decades. Like in the spin-$1/2$ case, we show that relativistic kinematical effects associated with spin are responsible for the distortions of the charge distributions seen in a moving frame. Applying our results to the deuteron, we observe a mild frame dependence compared to the nucleon case.

    hep-phnucl-thPRD(2022)·23 citations
28. 28*

    TMD Evolution Study of the $\cos 2\varphi$ Azimuthal Asymmetry in Unpolarized $J/\psi$ Production at EIC

    Jelle Bor🇳🇱 · Daniël Boer🇳🇱

    Semi-inclusive $J/\psi$ production in electron-proton collisions is a promising process to study gluon transverse momentum distributions (TMDs) at the future Electron-Ion Collider. In this article, we improve on previous studies of the $\cos 2\varphi$ azimuthal asymmetry that arises from the linear polarization of gluons inside unpolarized protons by including TMD evolution. We find that in the TMD regime the asymmetry grows monotonically with increasing transverse momentum of the outgoing $J/\psi$, in contrast to tree level calculations with Gaussian TMDs. Our predictions for the asymmetry at EIC can become very large at larger $x$, $Q$, and transverse momenta, even larger than the positivity bound. This problem stems from the very small $b$ region and implies a range of validity of TMD factorization that is more restricted than usually expected. We also include an estimate of the nonperturbative uncertainty from the large $b$ region and we conclude that it is smaller than the largest source of uncertainty, which stems from the choice of Color Octet Long-Distance Matrix Elements.

    hep-phPRD(2022)·29 citations
29. 29*

    Back-to-back azimuthal correlations in Z+jet events at high transverse momentum in the TMD parton branching method at next-to-leading order

    H. Yang🇨🇳 · A. Bermudez Martinez🇩🇪 · L.I. Estevez Banos🇩🇪 · F. Hautmann🇧🇪 · H. Jung🇩🇪 · M. Mendizabal🇩🇪 · K. Moral Figueroa🇬🇧 · S. Prestel🇸🇪 · S. Taheri Monfared🇩🇪 · A.M. van Kampen🇧🇪 · Q. Wang🇨🇳 · K. Wichmann🇩🇪

    Azimuthal correlations in Z+jet production at large transverse momenta are computed by matching Parton - Branching (PB) TMD parton distributions and showers with NLO calculations via MCatNLO. The predictions are compared with those for dijet production in the same kinematic range. The azimuthal correlations $\Delta \varphi$ between the Z boson and the leading jet are steeper compared to those in dijet production at transverse momenta $\mathcal{O}(100)$ GeV, while they become similar for very high transverse momenta $\mathcal{O}(1000)$ GeV. The different patterns of Z+jet and dijet azimuthal correlations can be used to search for potential {\it factorization - breaking} effects in the back-to-back region, which depend on the different color and spin structure of the final states and their interferences with the initial states. In order to investigate these effects experimentally, we propose to measure the ratio of the distributions in $\Delta \varphi$ for Z+jet - and multijet production at low and at high transverse momenta, and compare the results to predictions obtained assuming factorization. We examine the role of theoretical uncertainties by performing variations of the factorization scale, renormalization scale and matching scale. In particular, we present a comparative study of matching scale uncertainties in the cases of PB-TMD and collinear parton showers.

    hep-phnucl-thEPJC(2022)·37 citations
30. 30*

    Reply to "comment on `Scrutinizing $\pi \pi$ scattering in light of recent lattice phase shifts'"

    Xiu-Li Gao🇨🇳 · Zhi-Hui Guo🇨🇳 · Zhiguang Xiao🇨🇳 · Zhi-Yong Zhou🇨🇳

    We reply to the comment [arxiv:2202.08809] by E. van Beveren and G. Rupp on our recent work [arxiv:2202.03124], by further clarifying the difference between the two approaches. We emphasize that the left-hand cuts and constraints of crossing symmetry play an important role in reliably extracting the poles' information below the $\pi \pi$ threshold.

    hep-phPRD(2023)·3 citations
31. 31*

    Complementarity of direct detection experiments in search of light Dark Matter

    J. R. Angevaare🇳🇱 · G. Bertone🇳🇱 · A. P. Colijn🇳🇱 · M. P. Decowski🇳🇱 · B. J. Kavanagh🇪🇸

    Dark Matter experiments searching for Weakly interacting massive particles (WIMPs) primarily use nuclear recoils (NRs) in their attempt to detect WIMPs. Migdal-induced electronic recoils (ERs) provide additional sensitivity to light Dark Matter with $\mathcal{O}(\text{GeV}/c^2)$ masses. In this work, we use Bayesian inference to find the parameter space where future detectors like XENONnT and SuperCDMS SNOLAB will be able to detect WIMP Dark Matter through NRs, Migdal-induced ERs or a combination thereof. We identify regions where each detector is best at constraining the Dark Matter mass and spin independent cross-section and infer where two or more detection configurations are complementary to constraining these Dark Matter parameters through a combined analysis.

    hep-phastro-ph.COJCAP(2022)·4 citations
32. 32*

    Exploring the potential of FCC-hh to search for particles from $B$ mesons

    Alexey Boyarsky🇳🇱 · Oleksii Mikulenko🇳🇱 · Maksym Ovchynnikov🇳🇱 · Lesya Shchutska🇨🇭

    The Future Circular Collider (FCC-hh) is a proposed successor of the Large Hadron Collider (LHC). FCC-hh would push both the energy and intensity frontiers of searches for new physics particles. In particular, due to higher energy and luminosity than at the LHC, at FCC-hh there would be produced around $\simeq 30$ times larger amount of $B$ mesons and $\simeq 120$ times of $W$ bosons, which then may decay into feebly interacting particles. In this paper we demonstrate the potential of FCC-hh by studying its sensitivity to heavy neutral leptons (HNLs) with masses $m_N<m_B$. We consider various locations of a displaced decay volume embedded in the planned infrastructure of FCC-hh. We demonstrate that FCC-hh may substantially improve the reach of the parameter space of HNLs as compared to the searches proposed at the LHC.

    hep-phhep-exJHEP(2023)·22 citations
33. 33*

    Shear Viscosity of hadronic matter at finite temperature and magnetic field

    Ritesh Ghosh🇮🇳 · Najmul Haque🇮🇳

    We calculate the transport coefficient of hadronic matter in the presence of temperature and magnetic field using the linear sigma model. In the relaxation time approximation, we estimate the shear viscosity over entropy density $\eta /s$. The point-like interaction rates of hadrons are evaluated through the $S$-matrix approach in the presence of a magnetic field to obtain the temperature and magnetic field-dependent relaxation time. We observe that the transport coefficients are anisotropic in the presence of the magnetic field. We calculate the temperature and magnetic field-dependent anisotropic shear viscosity coefficients by incorporating the estimated relaxation time. The value of viscosity over entropy density is lower in the presence of a magnetic field than the value of it in a thermal medium. The behavior of the perpendicular components of the shear-viscous coefficient is also discussed. We consider the temperature-dependent hadron masses from mean-field effects in this work.

    hep-phnucl-thPRD(2022)·27 citations
34. 34*

    Highlights of pion and kaon structure from continuum analyses

    Khépani Raya🇪🇸 · José Rodríguez-Quintero🇪🇸

    One of the biggest challenges in contemporary physics is understanding the origin and dynamics of the internal structure of hadrons which, at a fundamental level, is described by quantum chromodynamics (QCD). Taking great prominence amongst hadrons are pions and kaons which, despite being the lightest hadrons in nature, their very existence is intimately connected to those mechanisms responsible for almost all of the mass of the visible matter. In this manuscript we discuss many aspects of the pion and kaon structure via light front wave functions and generalized parton distributions, and a collection of other distributions and structural properties that are inferred therefrom.

    hep-phnucl-thRev.Mex.Fis.Suppl.(2022)·11 citations
35. 35*

    Dyson-Schwinger equations and the muon g-2

    Khépani Raya🇪🇸 · Adnan Bashir🇲🇽 · Ángel S. Miramontes🇲🇽 · Pablo Roig🇲🇽

    We present a brief introduction to the Dyson-Schwinger equations (DSEs) approach to hadron and high-energy physics. In particular, how this formalism is applied to calculate the electromagnetic form factors ${\gamma }^{\ast }{\gamma }^{\ast }\to {\text{P}}^0$ and ${\gamma }^{\ast }{\text{P}}^{\pm }\to {\text{P}}^{\pm }$ (with ${\text{P}}^{\pm }$ and ${\text{P}}^0$ charged and neutral ground-state pseudoscalar mesons, respectively) is discussed. Subsequently, the corresponding contributions of those form factors to the muon anomalous magnetic moment ($g-2$) are estimated. We look forward to promoting the DSE approach to address theoretical aspects of the muon $g-2$, highlighting some calculations that could be carried out in the future.

    hep-phnucl-thRev.Mex.Fis.Suppl.(2022)·5 citations
36. 36*

    Classical Yang Mills equations with sources: consequences of specific scalar potentials

    Igor de M. Froldi🇧🇷 · Fabio L. Braghin🇧🇷

    Some well known gauge scalar potential very often considered or used in the literature are investigated by means of the classical Yang Mills equations for the $SU(2)$ subgroups of $N_c=3$. By fixing a particular shape for the scalar potential, the resulting vector potentials and the corresponding color-charges sources are found. By adopting the spherical coordinate system, it is shown that spherically symmetric solutions, only dependent on the radial coordinate, are only possible for the Abelian limit, otherwise, there must have angle-dependent component(s). The following solutions for the scalar potential are investigated: the Coulomb potential and a non-spherically symmetric generalization, a linear potential $A_0(\vec{r})\sim (\kappa r)$, a Yukawa-type potential $A_0(\vec{r})\sim (C{e}^{-r/r_0}/r)$ and finite spatial regions in which the scalar potential assumes constant values. The corresponding chromo-electric and chromo-magnetic fields, as well as the color-charge densities, are found to have strong deviations from the spherical symmetric configurations. We speculate these types of non-spherically symmetric configurations may contribute (or favor) for the (anisotropic) confinement mechanism since they should favor color charge-anti-charge (or three-color-charge) bound states that are intrinsically non spherically symmetric with (asymmetric) confinement of fluxes. Specific conditions and relations between the parameters of the solutions are also presented.

    hep-phhep-thAnnals Phys.(2022)·2 citations
37. 37*

    Kaon, Nucleon and ${\Delta }^{\ast }$ Resonances with Hidden Charm

    Brenda B. Malabarba🇧🇷 · A. M. Torres🇧🇷 · K.P. Khemchandani🇧🇷 · Xiu-Lei Ren🇩🇪 · Li-Sheng Geng🇨🇳

    In this presentation we discuss the generation of hadrons with an exotic quark content and hidden charm emerging from three-body interactions. To be more specific, we have studied the $KD{\bar{D}}^{\ast }/K\bar{D}{D}^{\ast }$ and $ND{\bar{D}}^{\ast }/N\bar{D}{D}^{\ast }$ systems and predicted states generated from the respective three-body dynamics. In the case of the $KD{\bar{D}}^{\ast }/K\bar{D}{D}^{\ast }$ system we predict the formation of a meson state with mass around $4307$ MeV and quantum numbers $I(J^P)=1/2(1^{-})$, $K^{\ast }(4307)$, and from the study of the $ND{\bar{D}}^{\ast }/N\bar{D}{D}^{\ast }$ system we found $N^{\ast }$ states with masses in the range $4400\sim 4600$ MeV, width of $2\sim 20$ MeV and positive parity.

    hep-phnucl-thPoS(2022)·0 citations
38. 38*

    Suppression of Higgs Mixing by Quantum Zeno Effect

    Kodai Sakurai🇯🇵 · Wen Yin🇯🇵

    The Higgs portal interaction to a singlet sector of the standard model (SM) gauge group is widely-studied. In this Letter, we show that a quantum effect is important if the Higgs field mixes with another singlet scalar field whose decay rate is larger than the mass difference between the two mass eigenstates. This effect may be interpreted as the quantum Zeno effect. In either the quantum mechanics or the quantum field theory, we show that the resulting propagating mode is not the eigenstate of the mass matrix, but it is approximately the eigenstate of the interaction. As a consequence, the decoupling of the mixing effect happens at the infinity limit of the decay width of the exotic scalar even if the naïve mixing parameter is not small. With a finite decay width of the exotic scalar, we derive the effective mass of the propagating mode in the SM sector, its decay rate, and the couplings at the 1-loop level. It turns out that the mixed mass eigenstates can mimic the discovered 125 GeV Higgs boson. This fuzzy Higgs boson can be obtained in a simple perturbative renormalizable model. It is consistent with the 125 GeV SM Higgs boson when the mass difference is smaller than $\mathcal{O}(0.1)$GeV ($\mathcal{O}(1)$GeV) for $\mathcal{O}(1)$ ($\mathcal{O}(0.01)$) mixing. We argue the possible natural scenario for the tiny mass splitting and the possibility that the upper bound of the mass difference is larger for a strongly-coupled singlet sector. To probe the fuzzy Higgs boson scenario, it is difficult to directly produce the singlet sector particles. Nevertheless, the future Higgs factories may probe this scenario by precisely measuring the Higgs boson invisible decay rate and the deviation of the Higgs coupling. Applications of the mechanism are also mentioned.

    hep-phhep-exhep-thEPJC(2023)·14 citations
39. 39*

    A Note on Proton Stability in the Standard Model

    Seth Koren🇺🇸

    In this short note we describe the symmetry responsible for absolute, nonperturbative proton stability in the Standard Model. The SM with $N_c$ colors and $N_g$ generations has an exact, anomaly-free, generation-independent, global symmetry group $U(1{)}_{B-N_{c}L}\times {\mathbb{Z}}_{N_g}^L$, which contains a subgroup of baryon plus lepton number of order $2N_c{N}_g$. This disallows proton decay for $N_g>1$. Many well-studied models beyond the SM explicitly break this global symmetry, and the alternative deserves further attention.

    hep-phhep-thUniverse(2022)·19 citations
40. 40*

    Dark Matter-Induced Multi-Phase Dynamical Symmetry Breaking

    Kristjan Kannike🇪🇪 · Niko Koivunen🇪🇪 · Aleksei Kubarski🇪🇪 · Luca Marzola🇪🇪 · Martti Raidal🇪🇪 · Alessandro Strumia🇮🇹 · Venno Vipp🇪🇪

    We consider the classically scale invariant Higgs-dilaton model of dynamical symmetry breaking extended with an extra scalar field that plays the role of dark matter. The Higgs boson is light near a critical boundary between different symmetry breaking phases, where quantum corrections beyond the usual Gildener-Weinberg approximation become relevant. This implies a tighter connection between dark matter and Higgs phenomenology. The model has only three free parameters, yet it allows for the observed relic abundance of dark matter while respecting all constraints. The direct detection cross section mediated by the Higgs boson is determined by the dark matter mass alone and is testable at future experiments.

    hep-phastro-ph.COPLB(2022)·13 citations
41. 41*

    Cosmological Lithium Solution from Discrete Gauged Baryon Minus Lepton Number

    Seth Koren🇺🇸

    The cosmological lithium problem -- that theory predicts a primordial abundance far higher than the observed value -- has resisted decades of attempts by cosmologists, nuclear physicists, and astronomers alike to root out systematics. We reconsider this problem in the setting of the Standard Model extended by gauged baryon minus lepton number, which we spontaneously break by a scalar with charge $2N_c{N}_g$. Cosmic strings from this breaking can support interactions converting three protons into three positrons, and we argue that an `electric'-`magnetic' interplay can give this process an amplified, strong-scale cross-section in an analogue of the Callan-Rubakov effect. We suggest such cosmic strings have disintegrated $\mathcal{O}(1)$ of the primordial lithium nuclei, and lay out what is necessary for this scheme to succeed. To our knowledge this is the first new physics mechanism with microphysical justification for the abundance of lithium uniquely to be modified after Big Bang Nucleosynthesis.

    hep-phastro-ph.COhep-thPRL(2023)·19 citations
42. 42*

    Effective Field Theory of Stückelberg Vector Bosons

    Graham D. Kribs🇺🇸 · Gabriel Lee🇺🇸 · Adam Martin🇺🇸

    We explore the effective field theory of a vector field $X^{\mu }$ that has a Stückelberg mass. The absence of a gauge symmetry for $X^{\mu }$ implies Lorentz-invariant operators are constructed directly from $X^{\mu }$. Beyond the kinetic and mass terms, allowed interactions at the renormalizable level include $X_{\mu }{X}^{\mu }{H}^{†}H$, $(X_{\mu }{X}^{\mu }{)}^2$, and $X_{\mu }{j}^{\mu }$, where $j^{\mu }$ is a global current of the SM or of a hidden sector. We show that all of these interactions lead to scattering amplitudes that grow with powers of $\sqrt{s}/m_X$, except for the case of $X_{\mu }{j}^{\mu }$ where $j^{\mu }$ is a \emph{nonanomalous} global current. The latter is well-known when $X$ is a dark photon coupled to the electromagnetic current, often written as kinetic mixing with the photon. Power counting for the energy growth of the scattering amplitudes is facilitated by isolating the longitudinal enhancement. We examine in detail the interaction with an \emph{anomalous} global vector current $X_{\mu }{j}_{\mathrm{anom}}^{\mu }$, carefully isolating the finite contribution to the fermion triangle diagram. We calculate the longitudinally-enhanced observables $Z\to X\gamma$ (when $m_X<m_Z$), $f\bar{f}\to X\gamma$, and $Z\gamma \to Z\gamma$ when $X$ couples to the baryon number current. Introducing a ``fake'' gauge-invariance by writing $X^{\mu }=A^{\mu }-{\partial }^{\mu }\pi /m_X$, the would-be gauge anomaly associated with $A_{\mu }{j}_{\mathrm{anom}}^{\mu }$ is canceled by $j_{\mathrm{anom}}^{\mu }{\partial }_{\mu }\pi /m_X$; this is the four-dimensional Green--Schwarz anomaly-cancellation mechanism at work. Our analysis demonstrates a larger set of interactions that an EFT with a Stückelberg vector field can have, revealing scattering amplitudes that grow with energy. This growth can be tamed by a dark Higgs sector, but this requires additional Higgs interactions that can be separated from $X$ only in the limit $g\ll 1$.

    hep-phPRD(2022)·40 citations
43. 43*

    Searching for dark radiation at the LHC

    Elias Bernreuther🇺🇸 · Felix Kahlhoefer🇩🇪 · Michele Lucente🇩🇪 · Alessandro Morandini🇩🇪

    In this work we explore the intriguing connections between searches for long-lived particles (LLPs) at the LHC and early universe cosmology. We study the non-thermal production of ultra-relativistic particles (i.e. dark radiation) in the early universe via the decay of weak-scale LLPs and show that the cosmologically interesting range $\Delta N_{\text{eff}}\sim 0.01-0.1$ corresponds to LLP decay lengths in the mm to cm range. These decay lengths lie at the boundary between prompt and displaced signatures at the LHC and can be comprehensively explored by combining searches for both. To illustrate this point, we consider a scenario where the LLP decays into a charged lepton and a (nearly) massless invisible particle. By reinterpreting searches for promptly decaying sleptons and for displaced leptons at both ATLAS and CMS we can then directly compare LHC exclusions with cosmological observables. We find that the CMB-S4 target value of $\Delta N_{\text{eff}}=0.06$ is already excluded by current LHC searches and even smaller values can be probed for LLP masses at the electroweak scale.

    hep-phJHEP(2022)·8 citations
44. 44*

    Potentialities of Hubble parameter and expansion rate function data to alleviate Hubble tension

    Yingjie Yang · Xuchen Lu · Lei Qian · Shulei Cao🇺🇸

    Taking advantage of Gaussian process (GP), we obtain an improved estimate of the Hubble constant, $H_0=70.41\pm 1.58$ km s${}^{-1}$ Mpc${}^{-1}$, using Hubble parameter [$H(z)$] from cosmic chronometers (CCH) and expansion rate function [$E(z)$], extracted from type Ia supernovae, data. We also use CCH data, including the ones with full covariance matrix, and $E(z)$ data to obtain a determination of $H_0=72.34_{-1.92}^{+1.90}$ km s${}^{-1}$ Mpc${}^{-1}$, which implies that the involvement of full covariance matrix results in higher values and uncertainties of $H_0$. These results are higher than those obtained by directly reconstructing CCH data with GP. In order to estimate the potential of future CCH data, we simulate two sets of $H(z)$ data and use them to constrain $H_0$ by either using GP reconstruction or fitting them with $E(z)$ data. We find that simulated $H(z)$ data alleviate $H_0$ tension by pushing $H_0$ values higher towards $\sim 70$ km s${}^{-1}$ Mpc${}^{-1}$. We also find that joint $H(z)$ + $E(z)$ data favor higher values of $H_0$, which is also confirmed by constraining $H_0$ in the flat concordance model and 2-order Taylor expansion of $H(z)$. In summary, we conclude that more and better-quality CCH data as well as $E(z)$ data can provide a new and useful perspective on resolving $H_0$ tension.

    ↳ astro-ph.COgr-qchep-phhep-thMNRAS(2023)·13 citations
45. 45*

    Multiparticle azimuthal cumulants from transverse momentum conservation and collective flow

    Mu-Ting Xie🇨🇳 · Guo-Liang Ma🇨🇳 · Adam Bzdak🇵🇱

    We calculate the $n$th order of $2k$-particle azimuthal cumulants $c_n\{2k\}$ based on transverse momentum conservation (TMC) and collective flow $v_n$(n=2,3). We demonstrate that the TMC effect only leads to a nonzero $c_n\{2k\}$ with the sign of $(-1{)}^{nk}$ and the magnitude inversely proportional to $(N-2k{)}^{nk}$. The interplay between TMC and collective flow can change the signs of $c_2\{4\}$, $c_3\{2\}$ and $c_3\{4\}$ at some values of multiplicity $N$, which could provide a good probe to study the onset of collectivity and search for the substructure of proton in small colliding systems.

    ↳ nucl-thhep-phnucl-exPRC(2022)·7 citations
46. 46*

    Spin and polarization: a new direction in relativistic heavy ion physics

    F. Becattini (University of Florence)🇮🇹

    Since the first evidence of a global polarization of $\Lambda$ hyperons in relativistic nuclear collisions in 2017, spin has opened a new window in the field, both at experimental and theoretical level, and an exciting perspective. The current state of the field is reviewed with regard to the theoretical understanding of the data, reporting on the most recent achievements and envisioning possible developments. The intriguing connections of spin physics in relativistic matter with fundamental questions in quantum field theory and applications in the non-relativistic domain are discussed.

    ↳ nucl-thhep-phnucl-exRept.Prog.Phys.(2022)·88 citations
47. 47*

    Neutral meson mixing in the $B_{(s)}^0$ sector from lattice QCD

    Justus Tobias Tsang🇩🇰

    We summarise the current status of lattice QCD computations of neutral meson parameters in the $B_d^0$ and the $B_s^0$ systems. We comment on recent results and anticipate further improvements on the uncertainties in the future.

    ↳ hep-lathep-phPoS(2023)·4 citations
48. 48*

    Muon g-2 with overlap valence fermions

    Gen Wang🇫🇷 · Terrence Draper🇺🇸 · Keh-Fei Liu🇺🇸 · Yi-Bo Yang ($\chi$ QCD Collaboration)🇨🇳

    We present a lattice calculation of the leading order (LO) hadronic vacuum polarization (HVP) contribution to the muon anomalous magnetic moment for the connected light and strange quarks, $a_{\mathrm{con},l/s}^{\mathrm{W}}$ in the widely used window $t_0=0.4\mathrm{fm}$, $t_1=1.0\mathrm{fm}$, $\Delta =0.15\mathrm{fm}$, and also of $a_{\mathrm{con},l/s}^{\mathrm{S}}$ in the short distance region. We use overlap fermions on 4 physical-point ensembles. Two 2+1 flavor RBC/UKQCD ensembles use domain wall fermions (DWF) and Iwasaki gauge actions at $a=0.084$ and 0.114 fm, and two 2+1+1 flavor MILC ensembles use the highly improved staggered quark (HISQ) and Symanzik gauge actions at $a=0.088$ and 0.121 fm. We have incorporated infinite volume corrections from 3 additional DWF ensembles at $\mathrm{L}$ = 4.8, 6.4 and 9.6 fm and physical pion mass. For $a_{\mathrm{con},l}^{\mathrm{W}}$, we find that our results on the two smaller lattice spacings are consistent with those using the unitary setup, but those at the two coarser lattice spacings are slightly different. Eventually, we predict $a_{\mathrm{con},l}^{\mathrm{W}}=206.7(1.5)(1.0)$ and $a_{\mathrm{con},s}^{\mathrm{W}}=26.8(0.1)(0.3)$, using linear extrapolation in $a^2$, with systematic uncertainties estimated from the difference of the central values from the RBC/UKQCD and MILC ensembles.

    ↳ hep-lathep-phPRD(2023)·108 citations
49. 49*

    Relativistic Spin Magnetohydrodynamics

    Samapan Bhadury🇮🇳 · Wojciech Florkowski🇵🇱 · Amaresh Jaiswal🇮🇳 · Avdhesh Kumar🇹🇼 · Radoslaw Ryblewski🇵🇱

    Starting from kinetic theory description of massive spin-1/2 particles in presence of magnetic field, equations for relativistic dissipative non-resistive magnetohydrodynamics are obtained in the small polarization limit. We use a relaxation time approximation for the collision kernel in the relativistic Boltzmann equation and calculate non-equilibrium corrections to the phase-space distribution function of spin-polarizable particles. We demonstrate that our framework naturally leads to emergence of the well known Einstein-de Hass and Barnett effects. We obtain multiple transport coefficients and show, for the first time, that the coupling between spin and magnetic field appear at gradient order in hydrodynamic equations.

    ↳ nucl-thhep-phhep-thPRL(2022)·84 citations
50. 50*

    Topological susceptibility in finite temperature QCD with physical $(u/d,s,c)$ domain-wall quarks

    Yu-Chih Chen🇹🇼 · Ting-Wai Chiu🇹🇼 · Tung-Han Hsieh🇹🇼

    We perform hybrid Monte-Carlo (HMC) simulation of lattice QCD with $N_f=2+1+1$ domain-wall quarks at the physical point, on the $64^3\times (64,20,16,12,10,8,6)$ lattices, each with three lattice spacings. The lattice spacings and the bare quark masses are determined on the $64^4$ lattices. The resulting gauge ensembles provide a basis for studying finite temperature QCD with $N_f=2+1+1$ domain-wall quarks at the physical point. In this paper, we determine the topological susceptibility of the QCD vacuum for $T>T_c\sim 150$ MeV. The topological charge of each gauge configuration is measured by the clover charge in the Wilson flow at the same flow time in physical units, and the topological susceptibility ${\chi }_t(a,T)$ is determined for each ensemble with lattice spacing $a$ and temperature $T$. Using the topological susceptibility ${\chi }_t(a,T)$ of 15 gauge ensembles with three lattice spacings and different temperatures in the range $T\sim 155-516$ MeV, we extract the topological susceptibility ${\chi }_t(T)$ in the continuum limit. To compare our results with others, we survey the continuum extrapolated ${\chi }_t(T)$ in lattice QCD with $N_f=2+1(+1)$ dynamical quarks at/near the physical point, and discuss their discrepancies. Moreover, a detailed discussion on the reweighting method for domain-wall fermion is presented.

    ↳ hep-lathep-phhep-thPRD(2022)·29 citations
51. 51*

    Exploring jet transport coefficients by elastic scattering in the strongly interacting quark-gluon plasma

    Ilia Grishmanovskii🇩🇪 · Taesoo Song🇩🇪 · Olga Soloveva🇩🇪 · Carsten Greiner🇩🇪 · Elena Bratkovskaya🇩🇪

    We study the interaction of leading jet partons in a strongly interacting quark-gluon plasma (sQGP) medium based on the effective dynamical quasi-particle model (DQPM). The DQPM describes the non-perturbative nature of the sQGP at finite temperature $T$ and baryon chemical potential ${\mu }_B$ based on a propagator representation of massive off-shell partons (quarks and gluons) whose properties (characterized by spectral functions with $T,{\mu }_B$ dependent masses and widths) are adjusted to reproduce the lQCD EoS for the QGP in thermodynamic equilibrium. We present the results for the jet transport coefficients, i.e. the transverse momentum transfer squared per unit length $\hat{q}$ as well as the energy loss per unit length $\Delta E=dE/dx$, in the QGP and investigate their dependence on the temperature $T$ and baryon chemical potential ${\mu }_B$ as well as on jet properties such as the leading jet parton momentum, mass, flavor, and the choice of the strong coupling constant. In this first study only elastic scattering processes of a leading jet parton with the sQGP partons are explored discarding presently the radiative processes (such as gluon Bremsstrahlung). We present a comparison of our results for the elastic energy loss in the sQGP medium with the pQCD results obtained by the BAMPS and LBT models as well as with other theoretical approaches such as lattice QCD and the LO-HTL and also with estimates of $\hat{q}/T^3$ by the color string percolation model (CSPM) and the JET and JETSCAPE Collaborations based on a comparison of hydrodynamical calculations with experimental heavy-ion data.

    ↳ nucl-thhep-phPRC(2022)·24 citations
52. 52*

    Numerov and phase-integral methods for charmonium

    Giampiero Esposito🇮🇹 · Pietro Santorelli🇮🇹

    This paper applies the Numerov and phase-integral methods to the stationary Schrodinger equation that studies bound states of charm anti-charm quarks. The former is a numerical method well suited for a matrix form of second-order ordinary di erential equations, and can be applied whenever the stationary states admit a Taylor-series expansion. The latter is an analytic method that provides, in principle, even exact solutions of the stationary Schrodinger equation, and well suited for applying matched asymptotic expansions and higher order quantization conditions. The Numerov method is found to be always in agreement with the early results of Eichten et al., whereas an original evaluation of the phase-integral quantization condition clarifies under which conditions the previous results in the literature on higher-order terms can be obtained.

    ↳ quant-phhep-phhep-thEur.Phys.J.Plus(2022)·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.