Tue·Dec 7, 2021Tuesday·December 7, 2021

1. 01*

   $\Delta$L=2 hyperon decays induced by Majorana neutrinos and doubly-charged scalars

   G. Hernández-Tomé🇲🇽 · G. López Castro🇲🇽 · D. Portillo-Sánchez🇲🇽

   Searches for $\Delta L=2$ decays are crucial to disentangle the Dirac vs Majorana nature of neutrinos. While neutrinoless nuclear double beta decays are the most promising tool to look for di-electron signals of $\Delta L=2$, searches of di-lepton channels with other flavors are far less limited by statistics. We revisit the calculation of $\Delta L=2$ decays of hyperons $B_i^{-}\to B_f^{+}{\ell }^{-}{\ell }^{\prime -}$. We compute the rates of these decays by including the hyperon form factors, which yields finite results in the one-loop model mechanism involving Majorana neutrinos (long-range contributions). In addition, we study the short-range contributions to these kinds of processes in two appealing scenarios. First, we consider the effects of heavy Majorana neutrinos in low-scale seesaw models that involve a minimal parametrization with only two heavy Majorana states. Second, we study an alternative model where $\Delta L=2$ decays are induced by a scalar boson coupled to di-leptons to provide additional predictions.

   hep-phPRD(2022)·12 citations
2. 02*

   Detecting Heavy Higgs Bosons from Natural SUSY at a 100 TeV Hadron Collider

   Howard Baer🇺🇸 · Vernon Barger🇺🇸 · Rishabh Jain🇹🇼 · Chung Kao🇺🇸 · Dibyashree Sengupta🇹🇼 · Xerxes Tata🇺🇸

   Supersymmetric models with radiatively-driven naturalness (RNS) enjoy low electroweak fine-tuning whilst respecting LHC search limits on gluinos and top squarks and allowing for $m_h\simeq 125$ GeV. While the heavier Higgs bosons $H,A$ may have TeV-scale masses, the SUSY conserving $\mu$ parameter must lie in the few hundred GeV range. Thus, in natural SUSY models there should occur large heavy Higgs boson branching fractions to electroweakinos, with Higgs boson decays to higgsino plus gaugino dominating when they are kinematically accessible. These SUSY decays can open up new avenues for discovery. We investigate the prospects of discovering heavy neutral Higgs bosons $H$ and $A$ decaying into light plus heavy chargino pairs which can yield a four isolated lepton plus missing transverse energy signature at the LHC and at a future 100 TeV $pp$ collider. We find that discovery of heavy Higgs decay to electroweakinos via its $4\ell$ decay mode is very difficult at HL-LHC. For FCC-hh or SPPC, we study the $H,A\to$ SUSY reaction along with dominant physics backgrounds from the Standard Model and devise suitable selection requirements to extract a clean signal for FCC-hh or SPPC with $\sqrt{s}=100$ TeV, assuming an integrated luminosity of 15 $a{b}^{-1}$. We find that while a conventional cut-and-count analysis yields a signal statistical significance greater than $5\sigma$ for $m_{A,H}\sim 1.1-1.65$ TeV, a boosted-decision-tree analysis allows for heavy Higgs signal discovery at FCC-hh or SPPC for $m_{A,H}\sim 1-2$ TeV.

   hep-phPRD(2022)·4 citations
3. 03*

   Four-fermion operators at dimension 6: dispersion relations and UV completions

   Aleksandr Azatov🇮🇹 · Diptimoy Ghosh🇮🇳 · Amartya Harsh Singh🇮🇳

   A major task in phenomenology today is constraining the parameter space of SMEFT and constructing models of fundamental physics that the SM derives from. To this effect, we report an exhaustive list of sum rules for 4-fermion operators of dimension 6, connecting low energy Wilson coefficients to cross-sections in the UV. Unlike their dimension 8 counterparts which are amenable to a positivity bound, the discussion here is more involved due to the weaker convergence and indefinite signs of the dispersion integrals. We illustrate this by providing examples with weakly coupled UV completions leading to opposite signs of the Wilson coefficients for both convergent and non-convergent dispersion integrals. We further decompose dispersion integrals under weak isospin and color groups which lead to a tighter relation between IR measurements and UV models. These sum rules can become an effective tool for constructing consistent UV completions for SMEFT following the prospective measurement of these Wilson coefficients.

   hep-phhep-thPRD(2022)·18 citations
4. 04*

   Next to SV resummed prediction for pseudoscalar Higgs boson production at NNLO$+\overline{\text{NNLL}}$

   Arunima Bhattacharya🇮🇳 · M. C. Kumar🇮🇳 · Prakash Mathews🇮🇳 · V. Ravindran🇮🇳

   We present first results on the resummation of Next-to-Soft Virtual (NSV) logarithms for the threshold production of pseudoscalar Higgs boson through gluon fusion at the LHC. These results are presented after resumming the NSV logarithms of the kind ${\log }^i(1-z)$ to $\overline{\text{NNLL}}$ accuracy and matching them systematically to the fixed order NNLO cross-sections. These results are obtained using collinear factorization, renormalization group invariance and recent developments in the NSV resummation techniques. The phenomenological implications of these NSV resummed results for 13 TeV LHC are studied and it is observed that these NSV logarithms are quite large. We also evaluate theory uncertainties and find that the renormalization scale uncertainties get reduced further with the inclusion of NSV corrections at various orders in QCD. We further study the impact of QCD corrections on mixed scalar-pseudoscalar states for different values of the mixing angle $\alpha$.

   hep-phPRD(2022)·15 citations
5. 05*

   Supersymmetric and Other Novel Features of Hadron Physics from Light-Front Holography

   Stanley J. Brodsky🇺🇸

   I survey recent developments in hadron physics which follow from the application of superconformal quantum mechanics and light-front holography. This includes new insights into the physics of color confinement, chiral symmetry, the spectroscopy and dynamics of hadrons, as well as surprising supersymmetric relations between the masses of mesons, baryons, and tetraquarks. I also will discuss some novel features of QCD -- such as color transparency, hidden color, and asymmetric intrinsic heavy-quark phenomena. The elimination of renormalization scale ambiguities and the modification of QCD sum rules due to diffractive phenomena are also briefly reviewed.

   hep-phhep-th5 citations
6. 06*

   Searching for the axion-like particle at the EIC

   Yandong Liu🇨🇳 · Bin Yan🇺🇸

   The axion-like particle (ALP) is a well motivated new particle candidate of beyond the Standard Model. In this work, we propose to probe the ALP through the photon fusion scattering at the upcoming Electron-Ion Collider (EIC) with electron and proton energy $E_e=20\mathrm{GeV}$ and $E_p=250\mathrm{GeV}$. It shows that we could constrain the effective coupling strength between ALP and photons to be $0.2{\mathrm{TeV}}^{-1}$ at $2\sigma$ confidence level with the integrated luminosity of $300{\mathrm{fb}}^{-1}$ for the mass range $m_a\in [5,40]\mathrm{GeV}$. Such bound could be much improved if we consider the nucleus beam at the EIC. We also demonstrate that the limits from the EIC could be stronger than the off $Z$-pole measurement at the LEP and the Light-by-Light scattering with pp collision at the LHC.

   hep-phhep-exnucl-exCPC(2023)·39 citations
7. 07*

   Restudy of the color-allowed two-body nonleptonic decay of bottom baryons ${\Xi }_b$ and ${\Omega }_b$ supported by hadron spectroscopy

   Yu-Shuai Li🇨🇳 · Xiang Liu🇨🇳

   In this work, we calculate the branching ratios of the color-allowed two-body nonleptonic decays of the bottom baryons, which include the ${\Xi }_b\to {\Xi }_c^{(\ast )}$ and ${\Omega }_b\to {\Omega }_c^{(\ast )}$ weak transitions by emitting a pseudoscalar meson (${\pi }^{-}$, $K^{-}$, $D^{-}$, and $D_s^{-}$) or a vector meson (${\rho }^{-}$, $K^{\ast -}$, $D^{\ast -}$, and $D_s^{\ast -}$). For achieving this aim, we adopt the three-body light-front quark model with the support of hadron spectroscopy, where the spatial wave functions of these heavy baryons involved in these weak decays are obtained by a semirelativistic potential model associated with the Gaussian expansion method. Our results show that these decays with the ${\pi }^{-}$, ${\rho }^{-}$, and $D_s^{(\ast )-}$-emitted mode have considerable widths, which could be accessible at the ongoing LHCb and Belle II experiments.

   hep-phhep-exPRD(2022)·19 citations
8. 08*

   Where are the hidden-charm hexaquarks?

   Zhe Liu🇨🇳 · Hong-Tao An🇨🇳 · Zhan-Wei Liu🇨🇳 · Xiang Liu🇨🇳

   In this work, we carry out the study of hidden-charm hexaquark states with the typical configurations $qqc\bar{q}\bar{q}\bar{c}$ ($q=u,d,s$). The mass spectra of hidden-charm hexaquark states are obtained within the chromo-magnetic interaction model. In addition to the mass spectra analysis, we further illustrate their two-body strong decay behaviors. There exist some compact bound states which cannot decay through the strong interaction. Hopefully our results will help to search for such types of the exotic states in the future experiments.

   hep-phPRD(2022)·23 citations
9. 09*

   Exploring Fermionic Multiplet Dark Matter through Precision Measurements at the CEPC

   Lin-Qing Gao🇨🇳 · Xiao-Jun Bi🇨🇳 · Jin-Wei Wang🇮🇹 · Qian-Fei Xiang🇨🇳 · Peng-Fei Yin🇨🇳

   New physics could be explored through loop effects by the precision measurements at the Circular Electron Positron Collider due to its clean collision environment and high luminosity. In this work, we focus on two dark matter models that involve additional electroweak fermionic multiplets. We calculate their one-loop corrections to five processes, i.e. $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-},Zh,ZZ,W^{+}{W}^{-}$, and $Z\gamma$, and investigate the corresponding signatures at CEPC with the projected sensitivity. We find that the detectable parameter regions of these processes are complementary. The combined analysis shows that the mass of dark matter $m_{{\chi }_1^0}$ in these two models can be probed up to $\sim 150\mathrm{GeV}$ and $\sim 450$ GeV at a 95\% confidence level, respectively.

   hep-phCPC(2022)·3 citations
10. 10*

    Analysis of $e^{+}{e}^{-}\to H^{\pm }{W}^{\mp }$ in the presence of a circularly polarized laser field

    J. Ou aali🇲🇦 · M. Ouhammou🇲🇦 · M. Ouali🇲🇦 · L. Rahili🇲🇦 · S. Taj🇲🇦 · B. Manaut🇲🇦

    In this study, we have investigated the production of a charged Higgs boson in assiciation with a charged weak $W$-boson ($H^{\pm }{W}^{\mp }$) at tree level via $e^{+}{e}^{-}$ annihilation in the presence of a laser field with circular polarization. At first step and by using analytical techniques, we have derived the expression of the differential cross section involving both $Z$ and $\gamma$ diagrams. Next, we have shown that the cross section of this process inside the laser field is proportional to the form factor $F_{HWV}$, and it depends on the mass of the charged Higgs boson and the energy of the center of mass. Then, we have analyzed the dependence of the total laser-assisted cross section on the number of photons exchanged for two different cases of form factor. Finally, we have found that the maximum number of photons that can be transferred depends only on the laser parameters.

    hep-phChin.J.Phys.(2022)·5 citations
11. 11*

    Production of $\Omega NN$ and $\Omega \Omega N$ in ultra-relativistic heavy ion collisions

    Liang Zhang🇨🇳 · Song Zhang🇨🇳 · Yu-Gang Ma🇨🇳

    Even though lots of $\Lambda$-hypernuclei have been found and measured, multi-strangeness hypernuclei consisting of $\Omega$ are not yet discovered. The studies of multi-strangeness hypernuclei help us further understand the interaction between hyperons and nucleons. Recently the $\Omega N$ and $\Omega \Omega$ interactions as well as binding energies were calculated by the HAL-QCD's lattice Quantum Chromo-Dynamics (LQCD) simulations and production rates of $\Omega$-dibaryon in Au + Au collisions at RHIC and Pb + Pb collisions at LHC energies were estimated by a coalescence model. The present work discusses the production of more exotic triple-baryons including $\Omega$, namely $\Omega NN$ and $\Omega \Omega N$ as well as their decay channels. A variation method is used in calculations of bound states and binding energy of $\Omega NN$ and $\Omega \Omega N$ with the potentials from the HAL-QCD's results. The productions of $\Omega NN$ and $\Omega \Omega N$ are predicted by using a blast-wave model plus coalescence model in ultra-relativistic heavy-ion collisions at $\sqrt{s_{NN}}=200$ GeV and $2.76$ TeV. Furthermore, plots for baryon number dependent yields of different baryons ($N$ and $\Omega$), their dibaryons and hypernuclei are made and the production rate of a more exotic tetra-baryon ($\Omega \Omega NN$) is extrapolated.

    hep-phnucl-exnucl-thEPJC(2022)·25 citations
12. 12*

    Leptophobic dark photon interpretation of the ${\eta }^{\left(\prime \right)}\to {\pi }^0\left(\eta \right)\gamma \gamma$ puzzle

    Yaroslav Balytskyi🇺🇸

    The decays of $\eta$ and ${\eta }^{\prime }$ mesons provide unique opportunities for testing the properties of low energy Quantum Chromodynamics and for the search of new physics beyond the Standard Model. However, recent experimental results on the rare decays of ${\eta }^{\left(\prime \right)}\to {\pi }^0\left(\eta \right)\gamma \gamma$ cannot be self-consistently described by the combination of the Vector Meson Dominance and Linear Sigma Model employing the same set of parameters. We show that this tension can be attributed to the presence of a leptophobic dark photon $\mathcal{B}$, and find representative values of the parameters which provide consistent description of these three decays, simultaneously. Unlike existing strategies of Dalitz analysis searching for the bump at $m_{\mathcal{B}}$, we propose the usage of mismatch between these decays to constrain the parameters of the hypothetical dark photon.

    hep-phnucl-thPLB(2023)·7 citations
13. 13*

    Exclusive hadronic $\tau$ decays, within $\&$ beyond the Standard Model

    P. Roig🇲🇽

    Semileptonic exclusive tau decays in the Standard Model are reviewed. As it is well-known, they are a privileged arena to learn about low-energy hadronization. They also allow for a number of clean new physics tests, which have attracted much attention recently, probing scales as high as a few TeV. In light of forthcoming Belle-II data, perspectives on this area are bright.

    hep-phhep-exSciPost Phys.Proc.(2025)·3 citations
14. 14*

    Effect of thermal shear on longitudinal spin polarization in a thermal model

    Wojciech Florkowski🇵🇱 · Avdhesh Kumar🇮🇳 · Aleksas Mazeliauskas🇨🇭 · Radoslaw Ryblewski🇵🇱

    By including the recently introduced thermal shear term that contributes to the spin polarization vector at local equilibrium, we determine longitudinal polarization of $\Lambda$ hyperons emitted from a hot and rotating hadronic medium using the thermal model with single freeze-out. In our analysis, we consider the RHIC top energies and use the model parameters which were determined in the earlier analyses of particle spectra and elliptic flow. We confirm that, unlike the previous calculations done by using only the thermal vorticity, the thermal shear term alone leads to the correct sign of the quadrupole structure of the longitudinal component of the polarization three-vector measured in experiments. However, we find almost complete cancellation between thermal shear and vorticity terms, which eventually leads to disagreement with the data. To clarify the role played by velocity and temperature gradient terms, we present a systematic analysis of different contributions to the longitudinal polarization.

    hep-phnucl-thPRC(2022)·61 citations
15. 15*

    Autoencoders for Semivisible Jet Detection

    Florencia Canelli🇨🇭 · Annapaola de Cosa🇨🇭 · Luc Le Pottier🇺🇸 · Jeremi Niedziela🇨🇭 · Kevin Pedro🇺🇸 · Maurizio Pierini🇨🇭

    The production of dark matter particles from confining dark sectors may lead to many novel experimental signatures. Depending on the details of the theory, dark quark production in proton-proton collisions could result in semivisible jets of particles: collimated sprays of dark hadrons of which only some are detectable by particle collider experiments. The experimental signature is characterised by the presence of reconstructed missing momentum collinear with the visible components of the jets. This complex topology is sensitive to detector inefficiencies and mis-reconstruction that generate artificial missing momentum. With this work, we propose a signal-agnostic strategy to reject ordinary jets and identify semivisible jets via anomaly detection techniques. A deep neural autoencoder network with jet substructure variables as input proves highly useful for analyzing anomalous jets. The study focuses on the semivisible jet signature; however, the technique can apply to any new physics model that predicts signatures with anomalous jets from non-SM particles.

    hep-phcs.LGhep-exJHEP(2022)·56 citations
16. 16*

    Solution of lepton $g-2$ anomalies with nonlocal QED

    Hang Li🇨🇳 · P. Wang🇨🇳

    The explanation for lepton $g-2$ anomalies is provided with the nonlocal QED which is the simple extension of the standard model. This solution is based on the same gauge symmetry as QED without introducing any new particles and interactions. The correlation functions in the nonlocal strength tension and lepton-photon interaction make it possible to explain the discrepancies of both $\Delta a_{\mu }$ and $\Delta a_e$. With the same approach, the discrepancy of anomalous magnetic moment of $\tau$ lepton from standard model is estimated in the range $1.19\times 10^{-5}$ to $3.21\times 10^{-3}$ which is covered by the current experimental uncertainty.

    hep-phJ.Phys.G(2023)·12 citations
17. 17*

    On the short-range behavior of neutrino forces beyond the Standard Model: from $1/r^5$ to $1/r^4$, $1/r^2$, and $1/r$

    Xun-jie Xu🇨🇳 · Bingrong Yu🇨🇳

    The exchange of a pair of neutrinos between two objects, seperated by a distance $r$, leads to a long-range effective potential proportional to $1/r_{}^5$, assuming massless neutrinos and four-fermion contact interactions. In this paper, we investigate how this known form of neutrino-mediated potentials might be altered if the distance $r$ is sufficiently short, corresponding to a sufficiently large momentum transfer which could invalidate the contact interactions. We consider two possible scenarios to open up the contact interactions by introducing a $t$-channel or an $s$-channel mediator. We derive a general formula that is valid to describe the potential in all regimes as long as the external particles remain non-relativistic. In both scenarios, the potential decreases as $1/r_{}^5$ in the long-range limit as expected. In the short-range limit, the $t$-channel potential exhibits the Coulomb-like behavior (i.e. proportional to $1/r$), while the $s$-channel potential exhibits $1/r_{}^4$ and $1/r_{}^2$ behaviors.

    hep-phastro-ph.COhep-thJHEP(2022)·23 citations
18. 18*

    Higher Order Corrections To The Lifetime Of Heavy Hadrons

    Maria Laura Piscopo🇩🇪

    In this work we discuss the theoretical status for the study of the lifetime of heavy hadrons. After presenting some introductory topics like the effective weak Hamiltonian and the heavy quark effective theory (HQET), we describe the construction of the heavy quark expansion (HQE), which constitutes the theoretical framework to systematically compute the total decay width of heavy hadrons, in terms of an expansion in inverse powers of the heavy quark mass. The structure of the HQE is discussed in detail, and the computation of the lowest dimensional contributions, explicitly outlined. Particular emphasis is put in describing the expansion of the quark propagator in the external gluon field using the Fock-Schwinger (FS) gauge, which represents a fundamental ingredient of the calculation. Moreover, the main result is the computation of the dimension-six contribution due to the Darwin operator, only recently determined and found to have a sizeable effect. Finally, we consider two phenomenological applications of the HQE in the charm sector, namely the study of the lifetime of charmed mesons and the analysis of the Glashow-Iliopoulos-Maiani (GIM) cancellations in neutral $D$-meson mixing. By comparing our results with recent measurements performed by the LHCb, Belle-II and BESIII collaborations, we conclude that the HQE is able to reproduce, within large theoretical uncertainties, the experimental pattern for the lifetimes of charmed mesons and we discuss a potential solution for the discrepancy of previous theoretical determinations of $D$-mixing with data.

    hep-ph11 citations
19. 19*

    The $D_{s}D{K}^{\ast }$ vertex in QCD Sum Rules: form factors and coupling constant

    A. Cerqueira Jr🇧🇷 · B. Osório Rodrigues🇧🇷 · M. E. Bracco🇧🇪 · C. M. Zanetti🇧🇪

    In this work we study the meson vertex $D_{s}D{K}^{\ast }$ using the QCD sum rules. We compute the three point correlation functions for the three cases of different off-shell mesons. The form factors for each case are fitted to the numerical calculation of the correlation functions and the coupling constant of the vertex is obtained by comparing the form factors at their respective off-shell meson pole. The result obtained for the coupling constant is $g_{D_{s}D{K}^{\ast }}=2.29_{-0.41}^{+0.65}$.

    hep-phBraz.J.Phys.(2022)·3 citations
20. 20*

    Massive quarks at one loop in the dipole picture of Deep Inelastic Scattering

    G. Beuf🇵🇱 · T. Lappi🇫🇮 · R. Paatelainen🇫🇮

    We calculate the light cone wave functions for a virtual photon to split into quark-antiquark states, including for the first time quark masses at one loop accuracy. These wave functions can be used to calculate cross sections for several precision probes of perturbative gluon saturation at the Electron-Ion Collider. Using these wave functions we derive, for the first time, the dipole picture DIS cross sections at one loop for longitudinal and transverse virtual photons including quark masses. The quark masses are renormalized in the pole mass scheme, satisfying constraints from the requirement of Lorentz invariance of the quark Dirac and Pauli form factors.

    hep-phhep-thPRL(2022)·55 citations
21. 21*

    Study of pT spectra of light particles using modified Hagedorn function and cosmic rays Monte Carlo event generators in proton-proton collisions at 900 GeV center of mass energy

    Muhammad Ajaz🇵🇰 · Muhammad Waqas🇨🇳 · Guang-Xiong Peng🇨🇳 · Zafar Yasin🇵🇰 · Hannan Younis🇵🇰 · Abd Al Karim Haj Ismai l🇦🇪

    Transverse momentum spectra of charged particles including pions, kaons and (anti-)protons measured by ALICE experiment in the pT range of 0.1-2.5 GeV/c and pseudorapidity less than 0.5 are studied in pp collisions at 900 GeV center of mass energy using modified Hagedorn function with embedded transverse flow velocity and are compared to the predictions of EPOS-LHC, Pythia, QGSJET and Sibyll models. We find that the average transverse flow velocity decreases with increasing the mass of the particle while the kinetic freeze-out temperature extracted from the function increases with the particle's mass. The former varies from 0.36 c to 0.25 c for pions to protons while the latter from 76 MeV to 95 MeV respectively. The fit of the models predictions also yield the same values for T0 and beta as the experimental data. The only difference is in the values of n, and N0 which yields different values for different models. The EPOS-LHC, Pythia, and QGSJET models reproduce the data in most of the pT range for pions, EPOS-LHC and Sibyll for kaons up to 1.5 GeV/c and EPOS-LHC for protons up to 1.6 GeV/c. The model simulations also reproduced the behavior of increasing average transverse momentum with mass reported by the ALICE experiment.

    hep-phEur.Phys.J.Plus(2022)·27 citations
22. 22*

    Resonances in ${\bar{\nu }}_e-e^{-}$ scattering below a TeV

    Vedran Brdar🇺🇸 · André de Gouvêa🇺🇸 · Pedro A. N. Machado🇺🇸 · Ryan Plestid🇺🇸

    We consider the resonant production and detection of charged mesons in existing and near-future neutrino scattering experiments with $E_{\nu }\lesssim 1$ TeV, characteristic of high-energy atmospheric neutrinos or collider-sourced neutrino beams. The most promising candidate is the reaction ${\bar{\nu }}_e{e}^{-}\to {\rho }^{-}\to {\pi }^{-}{\pi }^0$. We discuss detection prospects at FASER$\nu$, the LHC's forward physics facility with nuclear emulsion (FASER$\nu$2) and liquid argon detectors (FLArE) and estimate the number of expected resonance-mediated events in the existing data set of IceCube. We also outline possible detection strategies for the different experimental environments. We predict dozens of events at the forward physics facility and identify cuts with order one signal efficiency that could potentially suppress backgrounds at FASER$\nu$, yielding a signal-to-background ratio larger than 1. Antineutrino-induced $s$-channel meson resonances are yet unobserved Standard Model scattering processes which offer a realistic target for near-term experiments.

    hep-phhep-exPRD(2022)·11 citations
23. 23*

    The effective $\beta$ value in a Simple Harmonic Oscillator wave function

    Chao-hui Wang🇨🇳 · Long Tang🇺🇸 · Ting-yan Li🇨🇳 · Gong-ping Zheng🇨🇳 · Jing-fu Hu🇨🇳 · Cheng-qun Pang🇨🇳

    When a Simple Harmonic Oscillator (SHO) wave function is used as an effective wave function, a very important parameter in the SHO wave function is the effective $\beta$ value. We obtain the analytical expression of ${\beta }_{eff}$ (${\beta }_{effective}$) of the SHO wave function in coordinate space and momentum space. The expression is applied to the light meson system $(u\bar{u},u\bar{s})$ to compare the behavior of ${\beta }_{eff}$. The results show that ${\beta }_{eff,\mathbf{r}}$ in coordinate space and ${\beta }_{eff,\mathbf{p}}$ in momentum space are significantly different in the ground state, however, similar in the highly excited states with Cornell potential.

    hep-phquant-phNucl.Phys.Rev.(2022)·6 citations
24. 24*

    New approach to lattice QCD at finite density: reweighting without an overlap problem

    Attila Pasztor🇭🇺 · Szabolcs Borsanyi🇩🇪 · Zoltan Fodor🇩🇪 · Kornel Kapas🇭🇺 · Sandor D. Katz🇭🇺 · Matteo Giordano🇭🇺 · Daniel Nogradi🇭🇺 · Chik Him Wong🇩🇪

    Approaches to finite baryon density lattice QCD usually suffer from uncontrolled systematic uncertainties in addition to the well-known sign problem. We test a method - sign reweighting - that works directly at finite chemical potential and is yet free from any such uncontrolled systematics: with this approach the only problem is the sign problem itself. In practice the approach involves the generation of configurations with the positive fermionic weights given by the absolute value of the real part of the quark determinant, and a reweighting by a sign. There are only two sectors, +1 and -1 and as long as the average $⟨\pm ⟩\ne 0$ (with respect to the positive weight) this discrete reweighting has no overlap problem - unlike reweighting from $\mu =0$ - and the results are reliable. We also present results based on this algorithm on the phase diagram of lattice QCD with two different actions: as a first test, we apply the method to calculate the position of the critical endpoint with unimproved staggered fermions at $N_{\tau }=4$; as a second application, we study the phase diagram with 2stout improved staggered fermions at $N_{\tau }=6$. This second one is already a reasonably fine lattice - relevant for phenomenology. We demonstrate that the method penetrates the region of the phase diagram where the Taylor and imaginary chemical potential methods lose predictive power.

    ↳ hep-lathep-phnucl-thPoS(2022)·4 citations
25. 25*

    Lattice QCD Determination of the Bjorken-$x$ Dependence of Parton Distribution Functions at Next-to-next-to-leading Order

    Xiang Gao🇨🇳 · Andrew D. Hanlon🇺🇸 · Swagato Mukherjee🇺🇸 · Peter Petreczky🇺🇸 · Philipp Scior🇺🇸 · Sergey Syritsyn🇺🇸 · Yong Zhao🇺🇸

    We report the first lattice QCD calculation of pion valence quark distribution with next-to-next-to-leading order perturbative matching correction, which is done using two fine lattices with spacings $a=0.04$ fm and $0.06$ fm and valence pion mass $m_{\pi }=300$ MeV, at boost momentum as large as $2.42$ GeV. As a crucial step to control the systematics, we renormalize the pion valence quasi distribution in the recently proposed hybrid scheme, which features a Wilson-line mass subtraction at large distances in coordinate space, and develop a procedure to match it to the $\overline{\mathrm{MS}}$ scheme. We demonstrate that the renormalization and the perturbative matching in Bjorken-$x$ space yield a reliable determination of the valence quark distribution for $0.03\lesssim x\lesssim 0.80$ with 5-20\% uncertainties.

    ↳ hep-lathep-exhep-phnucl-ex+1PRL(2022)·96 citations
26. 26*

    Finite temperature QCD with physical $(u/d,s,c)$ domain-wall quarks

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

    In order to understand the role of QCD in the early universe, we perform hybrid Monte-Carlo simulation of lattice QCD with $N_f=2+1+1$ optimal domain-wall quarks at the physical point, on the $64^3\times (6,8,10,12,16,20,64)$ 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 Proceeding, we present our first result on the topological susceptibility of the QCD vacuum. 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.

    ↳ hep-lathep-phhep-thPoS(2022)·1 citation
27. 27*

    Laser-coolable AcOH${}^{+}$ ion for $\mathcal{C}\mathcal{P}$-violation searches

    Alexander V. Oleynichenko🇷🇺 · Leonid V. Skripnikov🇷🇺 · Andréi V. Zaitsevskii🇷🇺 · Victor V. Flambaum🇦🇺

    The AcOH${}^{+}$ molecular ion is identified as a prospective system to search for $\mathcal{C}\mathcal{P}$-violation effects. According to our study AcOH${}^{+}$ belongs to the class of laser-coolable polyatomic molecular cations implying the large coherence time in the experiments to study symmetry violating effects of fundamental interactions. We perform both nuclear and high level relativistic coupled cluster electronic structure calculations to express experimentally measurable $\mathcal{T}$,$\mathcal{P}$-violating energy shift in terms of fundamental quantities such as the nuclear magnetic quadrupole moment (MQM), electron electric dipole moment ($e$EDM) and dimensionless scalar-pseudoscalar nuclear-electron interaction constant. We further express nuclear MQM in terms of the strength constants of $\mathcal{C}\mathcal{P}$-violating nuclear forces: quantum chromodynamics vacuum angle $\bar{\theta }$ and quark chromo-EDMs. The equilibrium geometry of AcOH${}^{+}$ in the ground and the four lowest excited electronic states was found to be linear. The calculated Franck-Condon factors and transition dipole moments indicate that the laser cooling using optical cycle involving the first excited state is possible for the trapped AcOH${}^{+}$ ions with the Doppler limit estimated to be~$\sim 4$~nK. The lifetime of the (0,1${}^1$,0) excited vibrational state considered as a working one for MQM and $e$EDM search experiments is estimated to be $\sim 0.4$ sec.

    ↳ physics.atom-phhep-phnucl-thPRA(2022)·13 citations
28. 28*

    Magnetars as Laboratories for Strong Field QED

    Chul Min Kim (IBS, CoReLS and GIST)🇰🇷 · Sang Pyo Kim (Kunsan Natl U.)🇰🇷

    A strong electromagnetic field polarizes the vacuum and in the presence of an electric field creates pairs of a charged particle and its anti-particle. Magnetars, highly magnetized neutron stars with magnetic field comparable to or greater than the Schwinger field, give a significant amount of the vacuum polarization and vacuum birefringence and the induced electric field can create the electron-positron pairs, which are strong field quantum electrodynamics (QED) processes. In this paper, we use a closed formula for the one-loop effective action in the presence of a supercritical magnetic field and a subcritical electric field, find the vacuum birefringence analytically and numerically, and then discuss possible measurements in magnetars.

    ↳ astro-ph.HEhep-phAIP Conf.Proc.(2024)·16 citations
29. 29*

    Search for tetraquark states $X_{cc\bar{s}\bar{s}}$ in $D_s^{+}{D}_s^{+}(D_s^{\ast +}{D}_s^{\ast +})$ final states at Belle

    Belle Collaboration: X. Y. Gao · Y. Li · C. P. Shen · I. Adachi · H. Aihara · D. M. Asner · H. Atmacan · T. Aushev · R. Ayad · P. Behera · K. Belous · M. Bessner and 196 other authors

    A search for double-heavy tetraquark state candidates $X_{cc\bar{s}\bar{s}}$ decaying to $D_s^{+}{D}_s^{+}$ and $D_s^{\ast +}{D}_s^{\ast +}$ is presented for the first time using the data samples of 102 million ${\rm Y}(1S)$ and 158 million ${\rm Y}(2S)$ events, and the data samples at $\sqrt{s}$ = 10.52~GeV, 10.58~GeV, and 10.867~GeV corresponding to integrated luminosities of 89.5~fb${}^{-1}$, 711.0~fb${}^{-1}$, and 121.4~fb${}^{-1}$, respectively, accumulated with the Belle detector at the KEKB asymmetric energy electron-positron collider. The invariant-mass spectra of the $D_s^{+}{D}_s^{+}$ and $D_s^{\ast +}{D}_s^{\ast +}$ are studied to search for possible resonances. No significant signals are observed, and the 90\% confidence level upper limits on the product branching fractions [$\mathcal{B}({\rm Y}(1S,2S)\to X_{cc\bar{s}\bar{s}}+anything)\times \mathcal{B}(X_{cc\bar{s}\bar{s}}\to D_s^{+}{D}_s^{+}(D_s^{\ast +}{D}_s^{\ast +}))$] in ${\rm Y}(1S,2S)$ inclusive decays and the product values of Born cross section and branching fraction [$\sigma (e^{+}{e}^{-}\to X_{cc\bar{s}\bar{s}}+anything)\times \mathcal{B}(X_{cc\bar{s}\bar{s}}\to D_s^{+}{D}_s^{+}(D_s^{\ast +}{D}_s^{\ast +}))$] in $e^{+}{e}^{-}$ collisions at $\sqrt{s}$ = 10.52~GeV, 10.58~GeV, and 10.867~GeV under different assumptions of $X_{cc\bar{s}\bar{s}}$ masses and widths are obtained.

    ↳ hep-exhep-phPRD(2022)·16 citations
30. 30*

    Primordial Black Holes in Matter-Dominated Eras: the Role of Accretion

    V. De Luca🇨🇭 · G. Franciolini🇮🇹 · A. Kehagias🇬🇷 · P. Pani🇮🇹 · A. Riotto🇨🇭

    We consider the role of secondary infall and accretion onto an initially overdense perturbation in matter-dominated eras, like the one which is likely to follow the end of inflation. We show that primordial black holes may form through post-collapse accretion, namely the accretion onto an initial overdensity whose collapse has not given rise to a primordial black hole. Accretion may be also responsible for the growth of the primordial black hole masses by orders of magnitude till the end of the matter-dominated era.

    ↳ astro-ph.COgr-qchep-phPLB(2022)·43 citations
31. 31*

    Bifurcated symmetry breaking in scalar-tensor gravity

    M. Yoshimura🇯🇵

    We present models that simultaneously predict presence of dark energy and cold dark matter along with slow-roll inflation. The dark energy density is found to be of order $(\mathrm{a}\mathrm{few}\mathrm{meV}{)}^4$, and the mass of dark matter constituent is $\approx 1$ meV. These numbers are given in terms of the present value of Hubble constant $H_0$ and the Plank energy $1/\sqrt{16\pi G_N}$: they are $(H_0{M}_{\mathrm{P}}{)}^2$ for the energy density and $(H_0{M}_{\mathrm{P}}{)}^{1/2}$ for the dark matter constituent mass. The basic framework is a multi-scalar tensor gravity with non-trivial conformal coupling to the Ricci scalar curvature in the lagrangian density. The key for a right amount of dark energy is to incorporate in a novel way the spatially homogeneous kinetic contribution of Nambu-Goldstone modes in a spontaneously broken multi-scalar field sector. Proposed theories are made consistent with general relativity tests at small cosmological distances, yet are different from general relativity at cosmological scales. Dark matter is generated as spatially inhomogeneous component of the scalar system, with roughly comparable amount to the dark energy. In some presented models a cosmological bifurcation of symmetry breaking of scalar sector is triggered by the spontaneous breaking of electroweak SU(2) $\times$ U(1) gauge symmetry, hence the separation occurring simultaneously at the electroweak phase transition. The best experimental method to test presented models is to search for the fifth-force type of scalar exchange interaction with a force range, $O(10^{-2})$ cm, whose coupling to matter is basically of gravitational strength.

    ↳ gr-qcastro-ph.COhep-phhep-thPRD(2022)·6 citations
32. 32*

    Neutrino Mass Bounds in the era of Tension Cosmology

    Eleonora Di Valentino🇬🇧 · Alessandro Melchiorri🇮🇹

    The measurements of Cosmic Microwave Background anisotropies made by the Planck satellite provide extremely tight upper bounds on the total neutrino mass scale ($\Sigma m_{\nu }<0.26eV$ at $95\%$ C.L.). However, as recently discussed in the literature, Planck data show anomalies that could affect this result. Here we provide new constraints on neutrino masses using the recent and complementary CMB measurements from the Atacama Cosmology Telescope DR4 and the South Polar Telescope SPT-3G experiments. We found that both the ACT-DR4 and SPT-3G data, when combined with WMAP, mildly suggest a neutrino mass with $\Sigma m_{\nu }=0.68\pm 0.31$ eV and $\Sigma m_{\nu }=0.46_{-0.36}^{+0.14}$ eV at $68\%$ C.L, respectively. Moreover, when CMB lensing from the Planck experiment is included, the ACT-DR4 data now indicates a neutrino mass above the two standard deviations, with $\Sigma m_{\nu }=0.60_{-0.50}^{+0.44}$ eV at $95\%$, while WMAP+SPT-3G provides a weak upper limit of $\Sigma m_{\nu }<0.37$ eV at $68\%$ C.L.. Interestingly, these results are consistent with the Planck CMB+Lensing constraint of $\Sigma m_{\nu }=0.41_{-0.25}^{+0.17}$ eV at $68\%$ C.L. when variation in the $A_{\mathrm{lens}}$ parameter are considered. We also show that these indications are still present after the inclusion of BAO or SN-Ia data in extended cosmologies that are usually considered to solve the so-called Hubble tension. A combination of ACT-DR4, WMAP, BAO and constraints on the Hubble constant from the SH0ES collaboration gives $\Sigma m_{\nu }=0.39_{-0.25}^{+0.13}$ eV at $68\%$ C.L. in extended cosmologies. We conclude that a total neutrino mass above the $0.26$ eV limit still provides an excellent fit to several cosmological data and that future data must be considered before safely ruling it out.

    ↳ astro-ph.COgr-qchep-phApJL(2022)·97 citations
33. 33*

    First Glimpse into the Kaon Gluon Parton Distribution Using Lattice QCD

    Alejandro Salas-Chavira🇺🇸 · Zhouyou Fan🇺🇸 · Huey-Wen Lin🇺🇸

    In this work, we present the first results on the gluon parton distribution of the kaon from lattice quantum chromodynamics. We carry out the lattice calculation at pion mass around 310~MeV and two lattice spacings, 0.15 and 0.12~fm, using $2+1+1$-flavor HISQ ensembles generated by MILC Collaboration. The kaon correlators are calculated using clover fermions and momentum-smearing sources with maximum boost momentum around 2~GeV and high statistics (up to 324,000 measurements). We study the dependence of the resulting reduced Ioffe-time pseudo-distributions at multiple boost momenta and lattice spacings. We then extract the kaon gluon distribution function in the $\overline{\text{MS}}$ scheme at $\mu =2$~GeV, neglecting the mixing between the gluon and singlet-quark sectors. Our results at the smaller lattice spacing are consistent with phenomenological determinations.

    ↳ hep-lathep-phnucl-thPRD(2022)·49 citations
34. 34*

    Octet and decuplet baryon $\sigma$-terms and mass decompositions

    P. M. Copeland🇺🇸 · Chueng-Ryong Ji🇺🇸 · W. Melnitchouk🇺🇸

    We present a comprehensive analysis of the SU(3) octet and decuplet baryon masses and $\sigma$-terms using high-precision lattice QCD data and chiral SU(3) effective theory with finite range regularization. The effects of various systematic uncertainties, including from the scale setting of the lattice data and the regularization prescriptions, are quantified. We find the pion-nucleon and strange nucleon $\sigma$-terms to be ${\sigma }_{\pi N}=44(3)(3)$ MeV and ${\sigma }_{Ns}=50(6)(1)$ MeV, respectively. The results provide constraints on the energy-momentum tensor mass decompositions of the SU(3) octet and decuplet baryons, where we find the trace anomaly and quark/gluon energies decrease for strange baryons due to their larger strange $\sigma$-terms.

    ↳ nucl-thhep-lathep-phPRD(2023)·10 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.