Tue·Jul 13, 2021Tuesday·July 13, 2021

1. 01*

   Dark matter and lepton flavour phenomenology in a singlet-doublet scotogenic model

   Maud Sarazin🇫🇷 · Jordan Bernigaud🇩🇪 · Björn Herrmann🇫🇷

   We study the dark matter phenomenology of scotogenic frameworks through a rather illustrative model extending the Standard Model by scalar and fermionic singlets and doublets. Such a setup is phenomenologically attractive since it provides the radiative generation of neutrino masses, while also including viable candidates for cold dark matter. We employ a Markov Chain Monte Carlo algorithm to explore the associated parameter space in view of numerous constraints stemming from the Higgs mass, the neutrino sector, dark matter, and lepton-flavour violating processes. After a general discussion of the results, we focus on the case of fermionic dark matter, which remains rather uncovered in the literature so far. We discuss the associated phenomenology and show that in this particular case a rather specific mass spectrum is expected with fermion masses just above 1 TeV. Our study may serve as a guideline for future collider studies.

   hep-phJHEP(2021)·25 citations
2. 02*

   Sub-GeV $U(1{)}_R$ gauge boson to address the proton radius discrepancy

   Carlos Alvarado🇲🇽 · Alfredo Aranda🇲🇽 · Cesar Bonilla🇨🇱

   We propose a Standard Model extension by a $U(1{)}_R$ gauge symmetry where only right-handed chiral fermions can carry a non-trivial charge. Here we show that the simplest anomaly-free solution to accommodate the proton charge radius discrepancy takes right-handed muons ${\mu }_R$ and first generation quarks, $u_R$ and $d_R$. Consistency with the latest muon's $(g-2)$ measurements is achieved through an extra light scalar, which itself must lie in the tens of MeV mass range to be viable.

   hep-phhep-exPRD(2021)·2 citations
3. 03*

   Study of ${\Lambda }_c$${\Lambda }_c$ dibaryon and ${\Lambda }_c$${\bar{\Lambda }}_c$ baryonium states via QCD sum rules

   Xiu-Wu Wang🇨🇳 · Zhi-Gang Wang🇨🇳 · Guo-liang Yu🇨🇳

   In this article, we construct the six-quark currents with the $J^P=0^{+}$, $0^{-}$, $1^{+}$ and $1^{-}$ to study the ${\Lambda }_c$${\Lambda }_c$ dibaryon and ${\Lambda }_c$${\bar{\Lambda }}_c$ baryonium states via QCD sum rules. We consider the vacuum condensates up to dimension 16 and truncation of the order $\mathcal{O}({\alpha }_s^k)$ with $k\le 3$. The predicted masses are $5.11_{-0.12}^{+0.15}$GeV, $4.66_{-0.06}^{+0.10}$GeV, $4.99_{-0.09}^{+0.10}$GeV $4.68_{-0.08}^{+0.08}$GeV for the $J^P=0^{+}$, $0^{-}$, $1^{+}$ and $1^{-}$ states, respectively, which can be confronted to the experimental data in the future considering the high integrated luminosity at the center-of-mass energy about $4.8\mathrm{GeV}$ at the BESIII. We find the terms with $\frac{3}{2}<k\le 3$ do play a tiny role, and we can ignore these terms safely in the QCD sum rules.

   hep-phEPJA(2021)·38 citations
4. 04*

   Higgs boson decays to a fermion pair and a polarized $Z$ boson at NLO accuracy

   Zi-Qiang Chen🇨🇳 · Qi-Ming Feng🇨🇳 · Cong-Feng Qiao🇨🇳

   In this paper, we investigate the Higgs boson decay process $H\to f\bar{f}Z\to f\bar{f}{\mu }^{-}{\mu }^{+}$, where $f$ denotes any light fermions, at the next-to-leading order (NLO) accuracy. The calculation is performed within the framework of single-pole approximation, in which the contributions of different polarization states of the $Z$ boson are considered separately. Numerical results show that, by taking appropriate cut, the non-resonant background is negligible, and the NLO corrections are $1\%$--$4\%$ of the LO contributions. We also find that the inclusion of NLO corrections can greatly reduce the dependence on the electroweak coupling scheme, and enhance the prediction reliability. We formulate a method for the extraction of the pseudo-observable ${\Gamma }^{H\to ffZ}$ from the $f\bar{f}{\mu }^{-}{\mu }^{+}$ signal.

   hep-phPRD(2025)·3 citations
5. 05*

   Novel coupled channel framework connecting quark model and lattice QCD: an investigation on near-threshold $D_s$ states

   Zhi Yang🇨🇳 · Guang-Juan Wang🇯🇵 · Jia-Jun Wu🇨🇳 · Makoto Oka🇯🇵 · Shi-Lin Zhu🇨🇳

   A novel framework is proposed to extract near-threshold resonant states from finite-volume energy levels of lattice QCD and is applied to elucidate structures of the positive parity $D_s$. The quark model, the quark-pair-creation mechanism and $D^{(\ast )}K$ interaction are incorporated into the Hamiltonian effective field theory. The bare $1^{+}$ $c\bar{s}$ states are almost purely given by the states with heavy-quark spin bases. The physical $D_{s0}^{\ast }(2317)$ and $D_{s1}^{\ast }(2460)$ are the mixtures of bare $c\bar{s}$ core and $D^{(\ast )}K$ component, while the $D_{s1}^{\ast }(2536)$ and $D_{s2}^{\ast }(2573)$ are almost dominated by bare $c\bar{s}$. Furthermore, our model reproduces the clear level crossing of the $D_{s1}^{\ast }(2536)$ with the scattering state at a finite volume.

   hep-phhep-latPRL(2022)·86 citations
6. 06*

   The second-class current decays $\tau \to \pi \eta ({\eta }^{\prime }){\nu }_{\tau }$ in the NJL model including the interaction of mesons in the final state

   M.K. Volkov🇷🇺 · K. Nurlan🇷🇺 · A.A. Pivovarov🇷🇺

   The effect of the interaction of mesons in the final state is additionally considered within the description of $\tau \to \pi \eta ({\eta }^{\prime }){\nu }_{\tau }$ decays. This interaction is taken into account at the level of production of intermediate pions. One of them, in turn, might be transited into $\eta$ or ${\eta }^{\prime }$ mesons. Our results do not exceed the experimentally established branching fractions, and they are in agreement with the results of other theoretical studies.

   hep-phInt.J.Mod.Phys.A(2021)·3 citations
7. 07*

   Configuration mixing in strange tetraquarks $Z_{cs}$

   Marek Karliner🇮🇱 · Jonathan L. Rosner🇺🇸

   The BESIII Collaboration has observed a candidate for a $c\bar{c}s\bar{u}$ tetraquark $Z_{cs}$ at $(3982.5_{-2.6}^{+1.8}\pm 2.1)$ MeV and width $(12.8_{-4.4}^{+5.3}\pm 3.0)$ MeV, while the LHCb Collaboration has observed a $Z_{cs}$ candidate in the $\text{jpsi}{K}^{-}$ channel with mass of $(4003\pm 6_{-14}^{+4})$ MeV and width $(131\pm 15\pm 26)$ MeV. In this note we examine the possibility that these two states are distinct eigenstates of a mixing process similar to that which gives rise to two axial-vector mesons labeled by the Particle Data Group $K_1(1270)$ and $K_1(1400)$. The main point is that on top of a $\bar{c}c$ pair, the $Z_{cs}$ states have the same light quark content as the $K_1$-s. In the compact tetraquark picture this implies several additional states, analogous to members of the $K_1$ nonet. These states have not yet been observed, nor are they required in the molecular approach. Thus experimental discovery or exclusion of these extra states will be a critical test for competing models of exotic mesons with hidden charm.

   hep-phPRD(2021)·21 citations
8. 08*

   Lorentz-symmetry violation in the electroweak sector: scattering processes in future $e^{+}{e}^{-}$ colliders

   P. De Fabritiis🇧🇷 · P. C. Malta🇧🇷 · M. J. Neves🇧🇷

   We study CPT-odd non-minimal Lorentz-symmetry violating couplings in the electroweak sector modifying the interactions between leptons, gauge mediators and the Higgs boson. The tree-level (differential) cross sections for three important electroweak processes are discussed: $e^{+}{e}^{-}\to ZH$, $e^{+}{e}^{-}\to ZZ$ and $\gamma \gamma \to W^{+}{W}^{-}$. By considering next-generation $e^{+}{e}^{-}$ colliders reaching center-of-mass energies at the TeV scale and the estimated improved precision for the measurements of the respective cross sections, we are able to project upper bounds on the purely time-like background 4-vector as strict as $\lesssim 10^{-5}\text{mbox}{GeV}^{-1}$, in agreement with previous work on similar Lorentz-violating couplings.

   hep-phhep-thNPB(2022)·1 citation
9. 09*

   (3+1)-D viscous hydrodynamics CLVisc at finite net baryon density: identified particle spectra, anisotropic flows and flow fluctuations across BES energies

   Xiang-Yu Wu🇨🇳 · Guang-You Qin🇨🇳 · Long-Gang Pang🇨🇳 · Xin-Nian Wang🇨🇳

   To study the bulk properties of the quark-gluon-plasma (QGP) produced at the beam energy scan (BES) energies at the Relativistic Heavy Ion Collider (RHIC), we extend the (3+1)-dimensional viscous hydrodynamics CLVisc to include net baryon number conservation and Israel-Stewart-like equation for baryon diffusion with the NEOS-BQS equation of state, fluctuating initial conditions from Monte-Carlo Glauber model, and the afterburner SMASH. This integrated framework is shown to provide a good description of identified particle spectra, mean transverse momenta and anisotropic flows for different centralities and over a wide range of collision energies (7.7-62.4 GeV). It is found that the mean momenta of identified particles and anisotropic flows increases mildly with the collision energy due to larger radial flow. We further compute the multiple-particle cumulant ratio $v_2\{4\}/v_2\{2\}$ of elliptic flow across BES energies, and find that the relative fluctuations of elliptic flow are insensitive to the collision energy, consistent with the preliminary STAR data. Our model provides a benchmark for understanding the RHIC-BES data and studying the critical properties and phase structure of hot and dense QCD matter.

   hep-phnucl-exnucl-thPRC(2022)·101 citations
10. 10*

    Prediction of an ${\Omega }_{bbb}{\Omega }_{bbb}$ dibaryon in the extended one-boson exchange model

    Ming-Zhu Liu🇨🇳 · Li-Sheng Geng🇨🇳

    Ever since Yukawa proposed that the pion is responsible for mediating the nucleon-nucleon interaction, meson exchanges have been widely used in understanding hadron-hadron interactions. The most studied mesons are the $\sigma$, $\pi$, $\rho$, and $\omega$, while other heavier mesons are often argued to be less relevant because they lead to short range interactions. However, the ranges of interactions should be compared with the size of the system under study but not in absolute terms. In this work, we propose that one charmoninium exchange is responsible for the formation of the ${\Omega }_{ccc}{\Omega }_{ccc}$ dibaryon, recently predicted by lattice QCD simulations. The same approach can be extended to the strangeness and bottom sectors, leading to the prediction on the existence of $\Omega \Omega$ and ${\Omega }_{bbb}{\Omega }_{bbb}$ dibaryons, while the former is consistent with existing lattice QCD results, the latter remains to checked. In addition, we show that the Coulomb interaction may break up the ${\Omega }_{ccc}{\Omega }_{ccc}$ pair but not the ${\Omega }_{bbb}{\Omega }_{bbb}$ and $\Omega \Omega$ dibaryons, particularly, the latter.

    hep-phhep-exhep-latChin.Phys.Lett.(2021)·27 citations
11. 11*

    Can electron and muon $g-2$ anomalies be jointly explained in SUSY?

    Song Li🇨🇳 · Yang Xiao🇨🇳 · Jin Min Yang🇨🇳

    The FNAL+BNL measurements for muon $g-2$ is $4.2\sigma$ above the SM prediction, and the Berkeley ${}^{133}$Cs measurement for the fine-structure constant ${\alpha }_{\mathrm{em}}$ leads to the SM prediction for electron $g-2$ which is $2.4\sigma$ above the experimental value. Hence, a joint explanation of both anomalies requires a positive contribution to muon $g-2$ and a negative contribution to electron $g-2$, which is rather challenging. In this work we explore the possibility of such a joint explanation in the minimal supersymmetric standard model (MSSM). Assuming no universality between smuon and selectron soft masses, we find out a part of parameter space for a joint explanation at $2\sigma$ level, i.e., $\mu M_1,\mu M_2<0$, $m_{L1},m_{E2}<200$ GeV, $m_{L2}$ being much larger than the soft masses of other sleptons, $|M_1|<125$ GeV and $\mu <400$ GeV. This part of parameter space can survive LHC and LEP constraints, but gives an over-abundance for dark matter if the bino-like lightest neutralino is assumed to be the dark matter candidate. With the assumption that the dark matter candidate is a superWIMP (say a pseudo-goldstino in multi-sector SUSY breaking scenarios, whose mass can be as light as GeV and produced from the late-decay of the thermally freeze-out lightest neutralino), the dark matter problem can be avoided. So, we conclude that the MSSM may give a joint explanation for the muon and electron $g-2$ anomalies at $2\sigma$ level (the muon $g-2$ anomaly can be even ameliorated to $1\sigma$).

    hep-phhep-exEPJC(2022)·41 citations
12. 12*

    Time-dependent study of $K_S\to {\pi }^{+}{\pi }^{-}$ decays for flavour physics measurements

    P. Pakhlov🇷🇺 · V. Popov🇷🇺

    Nowadays High Energy Physics experiments can accumulate unprecedented statistics of heavy flavour decays that allows to apply new methods, based on the study of very rare phenomena, which used to be just desperate. In this paper we propose a new method to measure composition of $K^0$-${\overline{K}}^0$, produced in a decay of heavy hadrons. This composition contains important information, in particular about weak and strong phases between amplitudes of the produced $K^0$ and ${\overline{K}}^0$. We consider possibility to measure these parameters with time-dependent $K^0\to {\pi }^{+}{\pi }^{-}$ analysis. Due to $CP$-violation in kaon mixing time-dependent decay rates of $K^0$ and ${\overline{K}}^0$ differ, and the initial amplitudes revealed in the $CP$-violating decay pattern. In particular we consider cases of charmed hadrons decays: $D^{+}\to K^0{\pi }^{+}$, $D_s^{+}\to K^0{K}^{+}$, ${\Lambda }_c\to p{K}^0$ and with some assumptions $D^0\to K^0{\pi }^0$. This can be used to test the sum rule for charmed mesons and to obtain input for the full constraint of the two body amplitudes of $D$-mesons.

    hep-phJHEP(2021)·3 citations
13. 13*

    Bremsstrahlung photons from stopping in heavy-ion collisions

    Sohyun Park🇨🇭 · Urs Achim Wiedemann🇨🇭

    We examine the spectrum of bremsstrahlung photons that results from the stopping of the initial net charge distributions in ultrarelativistic nucleus-nucleus collisions at the CERN Large Hadron Collier (LHC). This effect has escaped detection so far since it becomes sizable only at very low transverse momentum and at sufficiently forward rapidity. We argue that it may be within reach of the next-generation LHC heavy-ion detector ALICE-3 that is currently under study, and we comment on the physics motivation for measuring it.

    hep-phhep-exnucl-thPRC(2021)·5 citations
14. 14*

    Properties of spin-1/2 heavy baryons at nonzero temperature

    A. Türkan🇹🇷 · G. Bozkır🇹🇷 · K. Azizi🇮🇷

    The spectroscopic properties of single heavy spin-1/2 ${\Lambda }_Q$, ${\Sigma }_Q$, ${\Xi }_Q^{(\prime )}$ and ${\Omega }_Q$ baryons are investigated at finite temperature in the framework of thermal QCD sum rule. We discuss the behavior of the mass and residue of these baryons with respect to temperature taking into account contributions of non-perturbative operators up to dimension eight. We include additional operators coming from the Wilson expansion due to breaking the Lorentz invariance at non-zero temperature. The obtained results show that the mass of these baryons remain stable up to roughly $T=108$ MeV while their residue are unchanged up to $T=93$ MeV. After these points, the mass and residue start to diminish by increasing the temperature. The shifts in the mass and residue for both the bottom and charm channels are considerably large and we observe the melting of these baryons near to the pseudo-critical temperature determined by recent lattice QCD calculations. We present our results for the mass of these baryons with both the positive and negative parity at $T\to 0$ limit, which are consistent with the existing theoretical predictions as well as experimental data.

    hep-phhep-exhep-latPRD(2021)·3 citations
15. 15*

    Two- and three-gluon glueballs of $C=+$

    Hua-Xing Chen🇨🇳 · Wei Chen🇨🇳 · Shi-Lin Zhu🇨🇳

    We study two- and three-gluon glueballs of $C=+$ using the method of QCD sum rules. We systematically construct their interpolating currents, and find that all the spin-1 currents of $C=+$ vanish. This suggests that the ``ground-state'' spin-1 glueballs of $C=+$ do not exist within the relativistic framework. We calculate masses of the two-gluon glueballs with $J^{PC}=0^{\pm +}/2^{\pm +}$ and the three-gluon glueballs with $J^{PC}=0^{\pm +}/2^{\pm +}$. We propose to search for the $J^{PC}=0^{-+}/2^{-\pm }/3^{\pm -}$ three-gluon glueballs in their three-meson decay channels in future BESIII, GlueX, LHC, and PANDA experiments.

    hep-phhep-exhep-latPRD(2021)·35 citations
16. 16*

    A complete description of P- and S-wave contributions to the $B^0\to K^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ decay

    Marcel Algueró🇪🇸 · Paula Alvarez Cartelle🇬🇧 · Alexander Mclean Marshall🇬🇧 · Pere Masjuan🇪🇸 · Joaquim Matias🇪🇸 · Michael Andrew McCann🇬🇧 · Mitesh Patel🇬🇧 · Konstantinos A. Petridis🇬🇧 · Mark Smith🇬🇧

    In this paper we present a detailed study of the four-body decay $B^0\to K^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$, where tensions with the Standard Model predictions have been observed. Our analysis of the decay with P- and S-wave contributions to the $K^{+}{\pi }^{-}$ system develops a complete understanding of the symmetries of the distribution, in the case of massless and massive leptons. In both cases, the symmetries determine relations between the observables in the $B^0\to K^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ decay distribution. This enables us to define the complete set of observables accessible to experiments, including several that have not previously been identified. The new observables arise when the decay rate is written differentially with respect to $m_{K\pi }$. We demonstrate that experiments will be able to fit this full decay distribution with currently available data sets and investigate the sensitivity to new physics scenarios given the experimental precision that is expected in the future. The symmetry relations provide a unique handle to explore the behaviour of S-wave observables by expressing them in terms of P-wave observables, therefore minimising the dependence on poorly-known S-wave form factors. Using this approach, we construct two theoretically clean S-wave observables and explore their sensitivity to new physics. By further exploiting the symmetry relations, we obtain the first bounds on the S-wave observables using two different methods and highlight how these relations may be used as cross-checks of the experimental methodology. We identify a zero-crossing point that would be at a common dilepton invariant mass for a subset of P- and S-wave observables, and explore the information on new physics and hadronic effects that this zero point can provide.

    hep-phhep-exJHEP(2021)·21 citations
17. 17*

    Study of CP violation in $B^{\pm }$ decays to $\overline{D^0}(D^0)K^{\pm }$ at FCCee

    R. Aleksan🇫🇷 · L. Oliver🇫🇷 · E. Perez🇨🇭

    The great progress made recently in the sector of Flavor Physics has enabled to establish CP violation in the B-meson decays. The unitarity triangle derived from the unitarity relation $V_{ub}^{\ast }{V}_{ud}+V_{cb}^{\ast }{V}_{cd}+V_{tb}^{\ast }{V}_{td}=0$ has been measured very precisely. To further asses our understanding of CP violation, it would be useful to carry out similar measurement of other triangles. In this note, we investigate the triangle derived from the relation $V_{ub}^{\ast }{V}_{us}+V_{cb}^{\ast }{V}_{cs}+V_{tb}^{\ast }{V}_{ts}=0$. Two angles of this triangle (${\alpha }_s$ and ${\beta }_s$) could be measured very accurately at FCCee using the decays $B_s(\overline{B_s})\to D_s^{\pm }{K}^{\mp }$ and $B_s(\overline{B_s})\to J/\psi \varphi$ respectively, as discussed elsewhere by us. This note concentrates on the measurement of the third angle ${\gamma }_s$ using the modes $B^{\pm }\to \overline{D^0}(D^0)K^{\pm }$. We show that a direct measurement of the angle ${\gamma }_s$ is possible with some specific $B^{\pm }$ decays with an estimated resolution of the order of 1${}^{\circ }$.

    hep-phhep-ex15 citations
18. 18*

    On mass generation in Landau-gauge Yang-Mills theory

    Gernot Eichmann🇵🇹 · Jan M. Pawlowski🇩🇪 · João M. Silva🇵🇹

    A longstanding question in QCD is the origin of the mass gap in the Yang-Mills sector of QCD, i.e., QCD without quarks. In Landau gauge QCD this mass gap, and hence confinement, is encoded in a mass gap of the gluon propagator, which is found both in lattice simulations and with functional approaches. While functional methods are well suited to unravel the mechanism behind the generation of the mass gap, a fully satisfactory answer has not yet been found. In this work we solve the coupled Dyson-Schwinger equations for the ghost propagator, gluon propagator and three-gluon vertex. We corroborate the findings of earlier works, namely that the mass gap generation is tied to the longitudinal projection of the gluon self-energy, which acts as an effective mass term in the equations. Because an explicit mass term is in conflict with gauge invariance, this leaves two possible scenarios: If it is viewed as an artifact, only the scaling solution survives; if it is dynamical, gauge invariance can only be preserved if there are longitudinal massless poles in either of the vertices. We find that there is indeed a massless pole in the ghost-gluon vertex, however in our approximation with the assumption of complete infrared dominance of the ghost this pole is only present for the scaling solution. We also put forward a possible mechanism that may reconcile the scaling solution, with an infrared dominance of the ghost, with the decoupling solutions based on longitudinal poles in the three-gluon vertex as seen in the PT-BFM scheme.

    hep-phhep-lathep-thPRD(2021)·56 citations
19. 19*

    Can $E_8$ unification at low energies be consistent with proton decay?

    Alfredo Aranda🇲🇽 · Francisco J. de Anda🇲🇽 · António P. Morais🇵🇹 · Roman Pasechnik🇸🇪

    A model is presented that achieves unification of the full Standard Model (SM) field content into a single superfield. It has $E_8$ as a gauge group and simple SUSY in ten spacetime dimensions. The extra dimensions are orbifolded such that they reduce the gauge symmetry directly to the SM one. At low energies, only the SM field content remains with viable unified Yukawa couplings. Full unification can be achieved at energies as low as $10^6\mathrm{GeV}$ with controlled proton decay.

    hep-ph3 citations
20. 20*

    Coupled-channel meson-meson scattering in the diabatic framework

    R. Bruschini🇪🇸 · P. González🇪🇸

    We apply the diabatic framework, a QCD-based formalism for the unified study of quarkoniumlike systems in terms of heavy quark-antiquark and open-flavor meson-meson components, to the description of coupled-channel meson-meson scattering. For this purpose, we first introduce a numerical scheme to find the solutions of the diabatic Schrödinger equation for energies in the continuum, then we derive a general formula for calculating the meson-meson scattering amplitudes from these solutions. We thus obtain a completely nonperturbative procedure for the calculation of open-flavor meson-meson scattering cross sections from the diabatic potential, which is directly connected to lattice QCD calculations. A comprehensive analysis of various elastic cross sections for open-charm and open-bottom meson-meson pairs is performed in a wide range of the center-of-mass energies. The relevant structures are identified, showing a spectrum of quasi-conventional and unconventional quarkoniumlike states. In addition to the customary Breit-Wigner peaks we obtain nontrivial structures such as threshold cusps and minimums. Finally, our results are compared with existing data and with results from our previous bound-state--based analysis, finding full compatibility with both.

    hep-phPRD(2021)·18 citations
21. 21*

    Sculpting the Standard Model from low-scale Gauge-Higgs-Matter $E_8$ Grand Unification in ten dimensions

    Alfredo Aranda🇲🇽 · Francisco J. de Anda🇲🇽 · António P. Morais🇵🇹 · Roman Pasechnik🇸🇪

    The construction and general implications of a model with complete supersymmetric unification of the Standard Model matter content, interactions and families' replication into a single $E_8$ gauge superfield in ten dimensions is presented. The gauge and extended Poincaré symmetries are broken through compactification of the ${\mathbb{T}}^6/({\mathbb{Z}}_3\times {\mathbb{Z}}_3)$ orbifold with Wilson lines, which reduces the original symmetry and matter content into those of the Standard Model plus additional heavier states. Proton decay can be suppressed automatically while the compactification scale may be as low as $10^9\mathrm{GeV}$, so that the corresponding GUT-scale physics may be potentially accessible and testable by future collider measurements.

    hep-phNPB(2023)·8 citations
22. 22*

    Following the trail of new physics via VBF Higgs signal at the Large Hadron Collider

    Tisa Biswas🇮🇳 · Anindya Datta🇮🇳 · Biswarup Mukhopadhyaya🇮🇳

    We investigate the modification of the Higgs signals from vector boson fusion at the LHC arising from higher-dimensional effective operators involving quarks, electroweak gauge bosons and the 125-GeV scalar discovered in 2012. Taking a few of the admissible dimension-6 operators as illustration, we work within the framework of the Standard Model Effective Field Theory (SMEFT) and identify kinematic variables that can reflect the presence of such effective operators. The useful variables turn out to be the geometric mean of the transverse momenta of the two forward jets produced in VBF and the rapidity difference between the two forward jets. We identify the shift in event population caused by the effective operators in the same, spanned by the above kinematic variables. Minimum values of the Wilson coefficients of the chosen dimension-6 operators are identified, for which they can be probed at the $3\sigma$ level in the high luminosity run of the LHC at 14 TeV. Projected exclusion limits on some of the couplings, obtained from our analysis, can significantly improve the limits on such couplings derived from electroweak precision data.

    hep-phPRD(2022)·11 citations
23. 23*

    Critical endpoint of QCD in a finite volume

    Julian Bernhardt🇩🇪 · Christian S. Fischer🇩🇪 · Philipp Isserstedt🇩🇪 · Bernd-Jochen Schaefer🇩🇪

    We investigate the impact of finite volume and the corresponding restrictions on long-range correlations on the location of the critical endpoint in the QCD phase diagram. To this end, we employ a sophisticated combination of lattice Yang--Mills theory and a (truncated) version of Dyson--Schwinger equations in Landau gauge for $2+1$ quark flavors that has been studied extensively in the past. In the infinite-volume limit, this system predicts a critical endpoint at moderate temperature and large chemical potential. We study this system at small and intermediate volumes and determine the dependence of the location of the critical endpoint on the boundary conditions and the volume of a three-dimensional cube with edge length $L$. We demonstrate that noticeable volume effects of more than five percent only occur for $L\lesssim 5\text{fm}$ and that volumes as large as $L^3\gtrsim (8\text{fm}{)}^3$ are very close to the infinite-volume limit.

    hep-phPRD(2021)·39 citations
24. 24*

    Defect Theory of Positronium and Nontrivial QED Relations

    David M. Jacobs🇺🇸

    An effective theory of the excited states of positronium is derived and some of its consequences are explored. At large physical separation, the binding of the electron and positron is assumed to be described completely by QED, whereas all short-ranged phenomena, including those within and beyond QED, can be accounted for with energy-dependent quantum defects. This theory has at least two practical applications. First, it provides an accurate and economical, yet largely QED-independent, means to fit the positronium spectrum in order to predict and compare the outcome of experiments. Second, matching the spectrum in this effective theory to that predicted by QED reveals nontrivial relationships that exist \emph{within} bound-state QED; some higher order contributions to the spectrum may be obtained from lower order contributions. These relations are verified up to order $m{\alpha }^6$, and predictions are made for the order $m{\alpha }^7$ and $m{\alpha }^8$ corrections. This theory and its extensions to other hydrogenic systems may provide a useful complement to bound-state QED.

    hep-phhep-thphysics.atom-phquant-phPRA(2021)·4 citations
25. 25*

    Polarization effects at finite temperature and magnetic field

    Pok Man Lo🇵🇱 · Michal Szymanski🇵🇱 · Krzysztof Redlich🇵🇱 · Chihiro Sasaki🇵🇱

    We study the screening of four-quark interaction by the ring diagram in an effective chiral quark model. This entails a medium dependent coupling which naturally reduces the chiral transition temperature in a class of models, and is capable of generating an inverse magnetic catalysis at finite temperature. These results are the first coherent description of inverse magnetic catalysis, anchored to a reliable field-theoretical basis.

    hep-phhep-latnucl-th3 citations
26. 26*

    An equation-of-state-meter for CBM using PointNet

    Manjunath Omana Kuttan🇩🇪 · Kai Zhou🇩🇪 · Jan Steinheimer🇩🇪 · Andreas Redelbach🇩🇪 · Horst Stoecker🇩🇪

    A novel method for identifying the nature of QCD transitions in heavy-ion collision experiments is introduced. PointNet based Deep Learning (DL) models are developed to classify the equation of state (EoS) that drives the hydrodynamic evolution of the system created in Au-Au collisions at 10 AGeV. The DL models were trained and evaluated in different hypothetical experimental situations. A decreased performance is observed when more realistic experimental effects (acceptance cuts and decreased resolutions) are taken into account. It is shown that the performance can be improved by combining multiple events to make predictions. The PointNet based models trained on the reconstructed tracks of charged particles from the CBM detector simulation discriminate a crossover transition from a first order phase transition with an accuracy of up to 99.8%. The models were subjected to several tests to evaluate the dependence of its performance on the centrality of the collisions and physical parameters of fluid dynamic simulations. The models are shown to work in a broad range of centralities (b=0-7 fm). However, the performance is found to improve for central collisions (b=0-3 fm). There is a drop in the performance when the model parameters lead to reduced duration of the fluid dynamic evolution or when less fraction of the medium undergoes the transition. These effects are due to the limitations of the underlying physics and the DL models are shown to be superior in its discrimination performance in comparison to conventional mean observables.

    hep-phnucl-exnucl-thJHEP(2021)·32 citations
27. 27*

    Constraints on Gluon Distribution Functions in the Nucleon and Nucleus from Open Charm Hadron Production at the Electron-Ion Collider

    Matthew Kelsey🇺🇸 · Reynier Cruz-Torres🇺🇸 · Xin Dong🇺🇸 · Yuanjing Ji🇺🇸 · Sooraj Radhakrishnan🇺🇸 · Ernst Sichtermann🇺🇸

    The Electron-Ion Collider (EIC) at Brookhaven National Laboratory will be a precision Quantum Chromodynamics machine that will enable a vast physics program with electron+proton/ion collisions across a broad center-of-mass range. Measurements of hard probes such as heavy flavor in deep inelastic scatterings will be an essential component to the EIC physics program and are one of the detector R\&D driving aspects. In this paper we study the projected statistical precision of open charm hadron production through exclusive hadronic channel reconstruction with a silicon detector concept currently being developed using a PYTHIA-based simulation. We further study the impact of possible intrinsic charm in the proton on projected data, and estimate the constraint on the nuclear gluon parton distribution function (PDF) from the charm structure functions $F_2^{c\overline{c}}$ in $e$+Au collisions using a Bayesian PDF re-weighting technique. Our studies show the EIC will be capable delivering an unprecedented measurement of charm hadron production across a broad kinematic region and will provide strong constraints to both intrinsic charm and nuclear gluon PDFs.

    hep-phhep-exnucl-exPRD(2021)·17 citations
28. 28*

    Cornering the Two Higgs Doublet Model Type II

    Oliver Atkinson🇬🇧 · Matthew Black🇩🇪 · Alexander Lenz🇩🇪 · Aleksey Rusov🇩🇪 · James Wynne🇬🇧

    We perform a comprehensive study of the allowed parameter space of the Two Higgs Doublet Model of Type II (2HDM-II). Using the theoretical framework flavio we combine the most recent flavour, collider and electroweak precision observables with theoretical constraints to obtain bounds on the mass spectrum of the theory. In particular we find that the 2HDM-II fits the data slightly better than the Standard Model (SM) with best fit values of the heavy Higgs masses around 2 TeV and a value of $\tan \beta \approx 4$. Moreover, we conclude that the wrong-sign limit is disfavoured by Higgs signal strengths and excluded by the global fit by more than five standard deviations and potential deviations from the alignment limit can only be tiny. Finally we test the consequences of our study on electroweak baryogenesis via the program package BSMPT and we find that the allowed parameter space strongly discourages a strong first order phase transition within the 2HDM-II.

    hep-phJHEP(2022)·64 citations
29. 29*

    Test of the hyperon-nucleon interaction within leading order covariant chiral effective field theory

    Jing Song🇨🇳 · Zhi-Wei Liu🇨🇳 · Kai-Wen Li🇨🇳 · Li-Sheng Geng🇨🇳

    Motivated by the recent experimental measurements of differential cross sections of the ${\Sigma }^{-}p$ elastic scattering in the momentum range of $470$ to $850$ MeV$/c$ by the J-PARC E$40$ experiment, we extend our previous studies of $S=-1$ hyperon-nucleon interactions to relatively higher energies up to $900$ MeV$/c$ for both the coupled-channel $\Lambda p\to (\Lambda p,{\Sigma }^{+}n,{\Sigma }^{0}p)$, ${\Sigma }^{-}p\to (\Lambda n,{\Sigma }^{0}n,{\Sigma }^{-}p)$ and single-channel ${\Sigma }^{+}p\to {\Sigma }^{+}p$ reactions. We show that although the leading order covariant chiral effective field theory is only constrained by the low energy data, it can describe the high energy data reasonably well, in particular, the J-PARC E40 differential cross sections. The predicted cusp structure close to the $\Sigma N$ threshold in the $\Lambda p\to \Lambda p$ reaction agrees with the latest ALICE observation as well as with the results of the next-to-leading order heavy baryon chiral effective theory. On the other hand, the comparison with the latest CLAS data on the $\Lambda p$ cross sections between 0.9 and 2.0 GeV$/c$ clearly indicates the need of higher order chiral potentials for such high momenta. This is also the case for the latest J-PARC data on the $\Sigma p\to \Lambda n$ differential cross sections. Nevertheless, even for these cases, the predictions are in qualitative agreement with the data, albeit with large uncertainties, implying that the predicted total and differential cross sections are of relevance for ongoing and planned experiments.

    ↳ nucl-thhep-exhep-lathep-ph+1PRC(2022)·32 citations
30. 30*

    Standard Model Physics and the Digital Quantum Revolution: Thoughts about the Interface

    Natalie Klco🇺🇸 · Alessandro Roggero🇺🇸 · Martin J. Savage🇺🇸

    Advances in isolating, controlling and entangling quantum systems are transforming what was once a curious feature of quantum mechanics into a vehicle for disruptive scientific and technological progress. Pursuing the vision articulated by Feynman, a concerted effort across many areas of research and development is introducing prototypical digital quantum devices into the computing ecosystem available to domain scientists. Through interactions with these early quantum devices, the abstract vision of exploring classically-intractable quantum systems is evolving toward becoming a tangible reality. Beyond catalyzing these technological advances, entanglement is enabling parallel progress as a diagnostic for quantum correlations and as an organizational tool, both guiding improved understanding of quantum many-body systems and quantum field theories defining and emerging from the Standard Model. From the perspective of three domain science theorists, this article compiles thoughts about the interface on entanglement, complexity, and quantum simulation in an effort to contextualize recent NISQ-era progress with the scientific objectives of nuclear and high-energy physics.

    ↳ quant-phhep-lathep-phnucl-thRept.Prog.Phys.(2022)·233 citations
31. 31*

    Flavor Anomalies in Heavy Quark Decays

    Johannes Albrecht🇩🇪 · Danny van Dyk🇩🇪 · Christoph Langenbruch🇩🇪

    Recent measurements of $b$-hadron decays show a pattern of consistent tensions with the respective Standard Model (SM) predictions. These tensions appear both in the sector of rare flavour-changing neutral currents and in tree-level semileptonic $b$-hadron decays. Flavour-changing neutral-current decays are loop-suppressed in the SM and are thus very susceptible to contributions from new heavy particles and/or new interactions beyond the SM. In rare semileptonic decays tensions are observed in measurements of branching fractions and angular observables, as well as in lepton flavour universality tests. Lepton flavour universality is also tested by comparing tree-level $b\to c{\ell }^{-}{\bar{\nu }}_{\tau }$ processes involving third generation leptons $\ell =\tau$ to semileptonic decays with light leptons $\ell =e,\mu$ in the final state. These tests also show tensions between measurements and the SM prediction. Taken together, these tensions constitute the so-called flavour anomalies in $b$-hadron decays, and could be first signs of New Physics (NP) beyond the SM, if established beyond any reasonable doubt. This article reviews both the current experimental status of the flavour anomalies and developments for the relevant theoretical predictions. The review concludes with a discussion of future prospects for the field.

    ↳ hep-exhep-phPPNP(2021)·88 citations
32. 32*

    ERLC (Twin LC) and LHC/FCC Based Electron-Proton Colliders

    B. Dagli🇹🇷 · B. Ketenoglu🇹🇷 · S. Sultansoy🇹🇷

    Construction of the ERLC (twin LC) collider tangential to LHC or FCC will give opportunity to realize ep collisions at multi-TeV center-of-mass energies. Luminosity estimations show that values well exceeding 10^34 cm^-2s^-1 can be achieved for HL-LHC, HE-LHC and FCC based ep colliders. Certainly, proposed ep colliders have great potential for clarifying QCD basics and new physics search in addition to providing precise PDFs for adequate interpretation of LHC and FCC experimental data.

    ↳ hep-exhep-phphysics.acc-ph3 citations
33. 33*

    Photon polarization effects in polarized electron-positron pair production in a strong laser field

    Ya-Nan Dai🇨🇳 · Bai-Fei Shen🇩🇪 · Jian-Xing Li🇨🇳 · Rashid Shaisultanov🇩🇪 · Karen Z. Hatsagortsyan🇩🇪 · Christoph H. Keitel🇩🇪 · Yue-Yue Chen🇨🇳

    Deep understanding of photon polarization impact on pair production is essential for the efficient creation of laser driven polarized positron beams, and demands a complete description of polarization effects in strong-field QED processes. We investigate, employing fully polarization resolved Monte Carlo simulations, the correlated photon and electron (positron) polarization effects in multiphoton Breit-Wheeler pair production process during the interaction of an ultrarelativistic electron beam with a counterpropagating elliptically polarized laser pulse. We showed that the polarization of e^-e^+ pairs is degraded by 35\%, when the polarization of the intermediate photon is resolved, accompanied with an approximately 13\% decrease of the pair yield. Moreover, the polarization direction of energetic positrons in small angle region is reversed, which originates from the pair production of hard photons with polarization parallel with electric field.

    ↳ physics.plasm-phhep-phMatter Radiat.Extremes(2022)·27 citations
34. 34*

    Quark anomalous magnetic moment and its effects on the $\rho$ meson properties

    Zanbin Xing🇨🇳 · Khépani Raya🇨🇳 · Lei Chang🇨🇳

    A symmetry-preserving treatment of mesons, within a Dyson-Schwinger and Bethe-Salpeter equations approach, demands an interconnection between the kernels of the quark gap equation and meson Bethe-Salpeter equation. Appealing to those symmetries expressed by the vector and axial-vector Ward-Green-Takahashi identitiges (WGTI), we construct a two-body Bethe-Salpeter kernel and study its implications in the vector channel; particularly, we analyze the structure of the quark-photon vertex, which explicitly develops a vector meson pole in the timelike axis and the quark anomlaous magnetic moment term, as well as a variety of $\rho$ meson properties: mass and decay constants, electromagnetic form factors, and valence-quark distribution amplitudes.

    ↳ nucl-thhep-phPRD(2021)·21 citations
35. 35*

    Could macroscopic dark matter (macros) give rise to mini-lightning flashes out of a blue sky without clouds?

    Vernon Cooray🇸🇪 · Gerald Cooray🇸🇪 · Marcos Rubinstein🇨🇭 · Farhad Rachidi🇨🇭

    A recent study pointed out that macroscopic dark matter (macros) traversing through the earth's atmosphere can give rise to hot and ionized channels similar to those associated with lightning leaders. The authors of the study investigated the possibility that when such channels created by macros pass through a thundercloud, lightning leaders may locked into these ionized channels creating lightning discharges with perfectly straight channels. They suggested the possibility of detecting such channels as a means of detecting the passage of macros through the atmosphere. In this paper, we show that macros crossing the atmosphere under fair weather conditions could also give rise to mini lightning flashes with current amplitudes in the order of few hundreds of Amperes. These mini lightning flashes would generate a thunder signature similar to or stronger than those of long laboratory sparks and they could also be detected by optical means. As in the case of thunderstorm assisted macro lightning, these mini-lightning flashes are also associated with straight channels. Moreover, since the frequency of mini lightning flashes are about three hundred times more frequent than the macro generated lightning flashes which were assisted by thunderstorms, they could be used as a means to look for the paths of macroscopic dark matter crossing the atmosphere.

    ↳ physics.ao-phastro-ph.IMhep-phAtmosphere 2021, 12, 1230·9 citations
36. 36*

    Vacuum bubble collisions: from microphysics to gravitational waves

    Oliver Gould🇬🇧 · Satumaaria Sukuvaara🇫🇮 · David Weir🇫🇮

    We comprehensively study the effects of bubble wall thickness and speed on the gravitational wave emission spectrum of collisions of two vacuum bubbles. We numerically simulate a large dynamical range, making use of symmetry to reduce the dimensionality. The high-frequency slope of the gravitational wave spectrum is shown to depend on the thickness of the bubble wall, becoming steeper for thick-wall bubbles, in agreement with recent fully 3+1 dimensional lattice simulations of many-bubble collisions. This dependence is present, even for highly relativistic bubble wall collisions. We use the reduced dimensionality as an opportunity to investigate dynamical phenomena which may underlie the observed differences in the gravitational wave spectra. These phenomena include `trapping', which occurs most for thin-wall bubbles, and oscillations behind the bubble wall, which occur for thick-wall bubbles.

    ↳ astro-ph.COgr-qchep-phPRD(2021)·28 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.