Tue·Jul 27, 2021Tuesday·July 27, 2021

1. 01*

   Exploring Uncharted Soft Displaced Vertices in Open Data

   Haipeng An🇨🇳 · Zhen Hu🇨🇳 · Zhen Liu🇺🇸 · Daneng Yang🇨🇳

   A cluster of soft displaced tracks corresponds to the dark matter co-annihilation regime. The long-lived regime is, in particular, motivated by the unexplored top partner physics. The background in this regime is extremely challenging to model using a traditional simulation method. We demonstrate the feasibility of handling the formidable background using the CMS Open Data. We perform this analysis to search for compressed and long-lived top partners in the 8 TeV CMS Open Data events with the integrated luminosity of 11.6 fb${}^{-1}$ and obtain new limits. With 15-30 GeV mass splitting between the top partner and the DM candidate, we exclude the top partner mass below 350 GeV, which is more stringent than the ATLAS and CMS results using 8 TeV data with 20 fb${}^{-1}$ luminosity. Our study also shows that the CMS Open Data can be a powerful tool to help physicists explore non-conventional new physics and even enable deriving new limits on exotic signals from data directly.

   hep-phhep-ex7 citations
2. 02*

   Geometric and Majorana phases in neutrino oscillations

   Lucas Johns🇺🇸

   Geometric (Aharonov--Anandan) phases in neutrino oscillations have been claimed [Phys. Lett. B 780 (2018) 216] to be sensitive to the Majorana phases in neutrino mixing. More recently, however, it has been pointed out [Phys. Lett. B 818 (2021) 136376] that the proposed phases are not gauge invariant. Using both kinematic and geometric approaches, we show that all gauge-invariant Aharonov--Anandan phases (including the off-diagonal geometric phases associated with flavor transitions) are independent of the Majorana phases. This finding, which generalizes the well-known fact that conventional oscillation experiments cannot discern the Dirac or Majorana nature of the neutrino, implies that a hypothetical interference experiment cannot distinguish between the two either.

   hep-phquant-phPRD(2022)·8 citations
3. 03*

   Axially symmetric particlelike solutions with the flux of a magnetic field in the non-Abelian Proca-Higgs theory

   Vladimir Dzhunushaliev🇰🇿 · Vladimir Folomeev🇰🇬

   Within the non-Abelian SU(2) Proca-Higgs theory, we study localised axially symmetric solutions possessing a finite field energy. It is shown that in a certain sense such solutions are analogues of the Nielsen-Olesen tube, since they have a longitudinal magnetic field creating a flux of this field over the central cross-section of the Proca tube. The main difference between the Proca tube and the Nielsen-Olesen tube is that the Proca tube is described by a topologically trivial solution and has finite size, since its energy density decreases exponentially with distance. The dependence of the total field mass of the Proca tube on the value of one of the parameters determining the solution is examined in detail. The solutions are obtained both in the presence and in the absence of external sources (charge and current densities).

   hep-phhep-thPRD(2021)·10 citations
4. 04*

   Quantum field-theoretical description of neutrino oscillations in magnetic field

   Vadim Egorov🇷🇺 · Igor Volobuev🇷🇺

   It is shown that the processes of neutrino oscillations in a magnetic field can be consistently described in the framework of a new quantum field-theoretical approach without use of the neutrino flavor states. It is based on the Feynman diagram technique with a modified distance-dependent propagator, which takes into account the geometry of neutrino oscillation experiments. Processes of neutrino oscillations in a magnetic field, where the neutrinos are detected through the weak charged- and neutral-current interaction, have been studied and numerical calculations have been carried out for some specific examples. Implications for the solar neutrinos are briefly discussed, and formulas for the asymptotic values of the normalized probability of solar neutrino oscillation processes are derived, which coincide with the observable ratio of the measurable neutrino flux to that predicted by the standard solar model.

   hep-phnucl-thJ.Exp.Theor.Phys.(2022)·10 citations
5. 05*

   Differentiating Dilatons from Axions by their mixing with photons

   Ankur Chaubey🇮🇳 · Manoj K. Jaiswal🇮🇳 · Damini Singh🇮🇳 · Venktesh Singh🇮🇳 · Avijit K. Ganguly🇮🇳

   According to the model ($\Lambda$CDM), based on deep cosmological observations, the current universe is constituted of 5$\%$ baryonic matter and 25 $\%$ non-baryonic cold dark matter (of speculative origin). These include quanta of scalar filed like dilaton($\varphi$) of scale symmetry origin and quanta of pseudoscalar field of extra standard model symmetry ( Peccei-Quinn) origin, like axion (${\varphi }^{\prime }$). These fields couple to di-photons through dim-5 operators. In magnetized medium, they in principle can interact with the three degrees of freedom (two transverse ($A_{\parallel ,\perp }$) and one longitudinal ($A_L$)) of photon($\gamma$) as long as the total spin is conserved. Because of intrinsic spin being zero, both $\varphi$ and ${\varphi }^{\prime }$ could in principle have interacted with $A_L$, (having $s_z=0$). However, out of $\varphi$ and ${\varphi }^{\prime }$ only one interacts with $A_L$. Furthermore, the ambient external magnetic field and media, breaks the intrinsic Lorentz symmetry of the system invoking Charge conjugation, Parity and Time reversal symmetries, we analyse the mixing dynamics of $\varphi \gamma$ and ${\varphi }^{\prime }\gamma$ systems and the structural {\it difference} of their mixing pattern. The strength of electromagnetic (EM) signals due to $\varphi \gamma$ and ${\varphi }^{\prime }\gamma$ mixing as a result would be {\it different}. We conclude by commenting on the possibility of detecting this {\it difference} -- in polarimetric observables the EMS -- using the existing space-borne detectors.

   hep-phastro-ph.HEhep-exEPJC(2024)·3 citations
6. 06*

   Analysis of kinetic freeze out temperature and transverse flow velocity in nucleus-nucleus and proton-proton collisions at same center of mass energy

   M. Waqas🇨🇳 · G.X Peng🇨🇳 · Z. Wazir🇵🇰 · Hailing Lao🇨🇳

   Transverse momentum spectra of different types of identified charged particles in central Gold-Gold (Au-Au) collisions, and inelastic (INEL) or non-single-diffrative (NSD) proton-proton (pp) collisions at the Relativistic Heavy Ion Collider (RHIC), as well as in central and peripheral Lead-Lead (Pb-Pb) collisions, and INEL or NSD pp collisions at the Large Hadron Collider (LHC) are analyzed by the blast wave model with Tsallis statistics. The model results are approximately in agreement with the experimental data measured by STAR, PHENIX and ALICE Collaborations in special transverse momentum ranges. Kinetic freeze out temperature and transverse flow velocity are extracted from the transverse momentum spectra of the particles. It is shown that kinetic freeze out temperature of the emission source depends on mass of the particles, which reveals the mass differential kinetic freeze out scenario in collisions at RHIC and LHC. Furthermore, the kinetic freeze out temperature and transverse flow velocity in central nucleus-nucleus (AA) collisions are larger than in peripheral collisions, and both of them are slightly larger in peripheral nucleus-nucleus collisions or almost equivalent to that in pp proton-proton collisions at the same center of mass energy which shows their similar thermodynamic nature.

   hep-phIJMPE(2021)·15 citations
7. 07*

   Prompt hadroproduction of C-even quarkonia in the light-front $k_T$ -factorization approach

   Wolfgang Schäfer🇵🇱 · Izabela Babiarz🇵🇱 · Roman Pasechnik🇸🇪 · Antoni Szczurek🇵🇱

   We present a new approach for the prompt production of quarkonia which is based on the $k_T$-factorization method. The production of even C-parity quarkonia proceeds via the fusion of two (off-shell) gluons. Especially in the kinematics of the LHCb experiment these processes are thus expected to be a sensitive probe of the small-$x$ gluon distribution. We calculate the relevant off-shell matrix elements in terms of the light-front wave functions of the quarkonium states. We present our results for scalar and pseudoscalar charmonia and discuss photon transition form factors as well as cross sections for prompt hadroproduction. We compare our results for the ${\eta }_c$ to recent LHCb data.

   hep-phSciPost Phys.Proc.(2022)·1 citation
8. 08*

   Primordial black holes and lepton flavor violation with scotogenic dark matter

   Teruyuki Kitabayashi🇯🇵

   We show that if the lepton flavor violating $\mu \to e\gamma$ process is observed in the MEG II experiment, the initial density of primordial black holes (PBHs) can be constrained with the scotogenic dark matter. As a benchmark case, if the PBH evaporation occurs in the radiation dominated era, the initial density may be $2\times 10^{-17}\lesssim \beta \lesssim 3\times 10^{-16}$ for $\mathcal{O}$ (TeV) scale dark sector in the scotogenic model where $\beta ={\rho }_{\mathrm{PBH}}/{\rho }_{\mathrm{rad}}$ is the ratio of the PBH density ${\rho }_{\mathrm{PBH}}$ to the radiation density ${\rho }_{\mathrm{rad}}$ at the time of PBH formation. As an other benchmark case, if PBHs evaporate in the PBH dominated era, the initial density may be $1\times 10^{-8}\lesssim \beta \lesssim 3\times 10^{-7}$ for $\mathcal{O}$ (GeV) scale dark matter with other $\mathcal{O}$ (TeV) scale particles in the scotogenic model.

   hep-phPTEP(2022)·9 citations
9. 09*

   QLBT: A linear Boltzmann transport model for heavy quarks in a quark-gluon plasma of quasi-particles

   Feng-Lei Liu🇨🇳 · Wen-Jing Xing🇨🇳 · Xiang-Yu Wu🇨🇳 · Guang-You Qin🇨🇳 · Shanshan Cao🇨🇳 · Xin-Nian Wang🇨🇳

   We develop a new heavy quark transport model, QLBT, to simulate the dynamical propagation of heavy quarks inside the quark-gluon plasma (QGP) created in relativistic heavy-ion collisions. Our QLBT model is based on the linear Boltzmann transport (LBT) model with the ideal QGP replaced by a collection of quasi-particles to account for the non-perturbative interactions among quarks and gluons of the hot QGP. The thermal masses of quasi-particles are fitted to the equation of state from lattice QCD simulations using the Bayesian statistical analysis method. Combining QLBT with our advanced hybrid fragmentation-coalescence hadronization approach, we calculate the nuclear modification factor $R_{\mathrm{AA}}$ and the elliptic flow $v_2$ of $D$ mesons at the Relativistic Heavy-Ion Collider and the Large Hadron Collider. By comparing our QLBT calculation to the experimental data on the $D$ meson $R_{\mathrm{AA}}$ and $v_2$, we extract the heavy quark transport parameter $\hat{q}$ and diffusion coefficient $D_{\mathrm{s}}$ in the temperature range of $1-4T_{\mathrm{c}}$, and compare them with the lattice QCD results and other phenomenological studies.

   hep-phnucl-exnucl-thEPJC(2022)·42 citations
10. 10*

    Jet shape and redistribution of the lost energy from jets in Pb+Pb collisions at the LHC in a multiphase transport model

    Ao Luo🇨🇳 · Ya-Xian Mao🇨🇳 · Guang-You Qin🇨🇳 · En-Ke Wang🇨🇳 · Han-Zhong Zhang🇨🇳

    Jet-medium interaction involves two important effects: jet energy loss and medium response. The search for jet-induced medium excitations is one of the hot topics in jet quenching study in relativistic nuclear collisions. In this work, we perform a systematic study on how the lost energy from hard jets evolves with the bulk medium and redistributes in the final state of heavy-ion collisions via a multi-phase transport model. In particular, the ($\Delta \eta ,\Delta \varphi$) distribution of charged particles with respect to the jet axis and jet shape function are studied for various Pb+Pb collision centralities and for different transverse momentum intervals of charged particles. Our numerical result shows a strong enhancement of soft particles at large angles for Pb+Pb collisions relative to p+p collisions at the LHC, qualitatively consistent with recent CMS data. This indicates that a significant fraction of the lost energy from hard jets is carried by soft particles at large angles away from the jet axis.

    hep-phnucl-exnucl-thEPJC(2022)·17 citations
11. 11*

    Laser-assisted kaon decay and CPT symmetry violation

    M. Baouahi🇲🇦 · M. Ouali🇲🇦 · M. Jakha🇲🇦 · S. Mouslih🇲🇦 · Y. Attaourti🇲🇦 · B. Manaut🇲🇦 · S. Taj🇲🇦

    In this paper, we have investigated the charged kaons decay at the lowest order in the presence of a circularly polarized laser field. To be more precise, we have examined the leptonic decay of both positive (matter) and negative (antimatter) kaon which weakly decay via the exchange of $W$ boson. Indeed, we have derived the expression of the leptonic decay width, the leptonic branching ratio, the leptonic ratio and the charged kaon lifetime by using the decay matrix approach. In addition, by using numerical computation, we have presented and discussed how the laser field influences these physical quantities. Moreover, we have analyzed the effect of the laser field on the parameter associated with the CPT symmetry. Then, we have concluded that, in the presence of an electromagnetic field and based on this CPT symmetry parameter, it is possible to control the dominance of matter over antimatter or vice-versa by applying an external field to either violate or conserve the CPT symmetry.

    hep-phquant-phLaser Phys.Lett.(2021)·21 citations
12. 12*

    Non-Abelian Vector Dark Matter and Lepton $g-2$

    Talal Ahmed Chowdhury🇧🇩 · Shaikh Saad🇨🇭

    The mystery of dark matter remains an unsettled problem of particle physics. On top of that, experiments show a persistent contention of the muon anomalous magnetic moment (AMM) relative to the Standard Model (SM) prediction. In this work, we consider the possibility of extending the SM with a non-Abelian gauge symmetry $SU(2{)}_X$, under which SM leptons transform non-trivially. SM leptons receive corrections to their AMMs of right order via one-loop processes mediated by beyond SM (BSM) fermions required to cancel anomalies, and BSM gauge bosons that play the role of dark matter. We show that simultaneous explanation of the the muon AMM along with reproducing correct relic abundance allows rather a narrow range of 0.5 - 2 TeV dark matter mass, consistent with current experimental constraints. However, a concurrent description that also includes electron AMM is challenging in this set-up.

    hep-phJCAP(2021)·31 citations
13. 13*

    The three point asymmetric cumulants in high multiplicity pp collisions

    B. Blok🇮🇱 · R. Segev (Technion)🇮🇱

    We study the influence of quantum interference and colour flow on three point correlations described by asymmetric cumulants in high multiplicity events in pp collisions. We use the model previously developed for the study of the collectivity in symmetric cumulants. We show that the resulting three point asymmetric cumulant is in qualitative agreement with the experimental data for the same parameters of the model as it was with the symmetric cumulants. Our results show that the initial state correlations must play a major role and may be even dominant in the explanation of the correlations in high multiplicity pp events.

    hep-phhep-exnucl-exnucl-thEPJC(2021)·1 citation
14. 14*

    Hilbert Series for Leptonic Flavor Invariants in the Minimal Seesaw Model

    Bingrong Yu🇨🇳 · Shun Zhou🇨🇳

    In this paper, we examine the leptonic flavor invariants in the minimal seesaw model (MSM), in which only two right-handed neutrino singlets are added into the Standard Model in order to accommodate tiny neutrino masses and explain cosmological matter-antimatter asymmetry via leptogenesis mechanism. For the first time, we calculate the Hilbert series (HS) for the leptonic flavor invariants in the MSM. With the HS we demonstrate that there are totally 38 basic flavor invariants, among which 18 invariants are CP-odd and the others are CP-even. Moreover, we explicitly construct these basic invariants, and any other flavor invariants in the MSM can be decomposed into the polynomials of them. Interestingly, we find that any flavor invariants in the effective theory at the low-energy scale can be expressed as rational functions of those in the full MSM at the high-energy scale. Practical applications to the phenomenological studies of the MSM, such as the sufficient and necessary conditions for CP conservation and CP asymmetries in leptogenesis, are also briefly discussed.

    hep-phJHEP(2021)·35 citations
15. 15*

    Spectral signatures of axionlike dark matter

    Alexander V. Gramolin🇺🇸 · Arne Wickenbrock🇩🇪 · Deniz Aybas🇺🇸 · Hendrik Bekker🇩🇪 · Dmitry Budker🇩🇪 · Gary P. Centers🇩🇪 · Nataniel L. Figueroa🇩🇪 · Derek F. Jackson Kimball🇺🇸 · Alexander O. Sushkov🇺🇸

    We derive spectral line shapes of the expected signal for a haloscope experiment searching for axionlike dark matter. The knowledge of these line shapes is needed to optimize an experimental design and data analysis procedure. We extend the previously known results for the axion-photon and axion-gluon couplings to the case of gradient (axion-fermion) coupling. A unique feature of the gradient interaction is its dependence not only on magnitudes but also on directions of velocities of galactic halo particles, which leads to the directional sensitivity of the corresponding haloscope. We also discuss the daily and annual modulations of the gradient signal caused by the Earth's rotational and orbital motions. In the case of detection, these periodic modulations will be an important confirmation that the signal is sourced by axionlike particles in the halo of our Galaxy.

    hep-phastro-ph.COhep-exphysics.atom-phPRD(2022)·41 citations
16. 16*

    Excitation spectra of heavy baryons in diquark models

    Kento Kumakawa🇯🇵 · Daisuke Jido🇯🇵

    The excitation energy spectra of heavy baryons consisting of a heavy quark and two light quarks are investigated by using diquark models in order to examine the nature of the diquark as a constituent of single heavy baryons. We consider two diquark models; in model A the diquark is treated as a point-like particle, while it has a spatial size in model B. We determine the masses of scalar and axial vector diquarks by the mass difference of the ground state charmed baryons to the ${\Lambda }_c$ baryon, while the mass of the $ud$ scalar diquark in the ${\Lambda }_c$ baryon is assumed to be 500 MeV as a reference. The parameters of these models are fixed by the $1p$ excitation energy of ${\Lambda }_c$. We find that model A reproduces well the excitation energy spectra of the charmed and bottomed baryons, although the string tension of the confinement potential in model A should be a half of that of the charmonium, while Model B suggests degeneracy of the $2s$ and $1d$ states, which is not seen in the ${\Lambda }_c$ spectrum.

    hep-phnucl-thPTEP(2022)·6 citations
17. 17*

    TeV Scale Modified Type-II Seesaw and Dark Matter in a Gauged $U(1{)}_{\mathrm{B}-\mathrm{L}}$ Symmetric Model

    Purusottam Ghosh (1)🇮🇳 · Satyabrata Mahapatra (2)🇮🇳 · Nimmala Narendra (3)🇮🇳 · Narendra Sahu (2) ((1) Harish-Chandra Research Institute, India (2) Indian Institute of Technology Hyderabad, India (3) Physical Research Laboratory, India)🇮🇳

    In an endeavor to explain the light neutrino masses and dark matter (DM) simultaneously, we study a gauged $U(1{)}_{\mathrm{B}-\mathrm{L}}$ extension of the standard model (SM). The neutrino masses are generated through a variant of type-II seesaw mechanism in which one of the scalar triplets has a mass in a scale that is accessible at the present generation colliders. Three SM singlet right chiral fermions ${\chi }_{iR}$($i=e,\mu ,\tau$) with $\mathrm{B}-\mathrm{L}$ charges -4, -4, +5 are invoked to cancel the $\mathrm{B}-\mathrm{L}$ gauge anomalies and the lightest one among these three fermions becomes a viable DM candidate as their stability is guaranteed by a remnant ${\mathcal{Z}}_2$ symmetry to which $U(1{)}_{\mathrm{B}-\mathrm{L}}$ gauge symmetry gets spontaneously broken. Interestingly in this scenario, the neutrino mass and the co-annihilation of DM are interlinked through the breaking of $U(1{)}_{\mathrm{B}-\mathrm{L}}$ symmetry. Apart from giving rise to the observed neutrino mass and dark matter abundance, the model also predicts exciting signals at the colliders. Especially we see a significant enhancement in the production cross-section of the TeV scale doubly charged scalar in presence of the $Z_{\mathrm{BL}}$ gauge boson. We discuss all the relevant constraints on model parameters from observed DM abundance and null detection of DM at direct and indirect search experiments as well as the constraints on the $\mathrm{B}-\mathrm{L}$ gauge boson from recent colliders.

    hep-phastro-ph.COPRD(2022)·16 citations
18. 18*

    Symmetry Finder applied to the 1-3 mass eigenstate exchange symmetry

    Hisakazu Minakata🇺🇸

    In a previous paper, Symmetry Finder (SF) method is proposed to find the reparametrization symmetry of the state-exchange type in neutrino oscillation in matter. It has been applied successfully to the 1-2 state exchange symmetry in the DMP perturbation theory, yielding the eight symmetries. In this paper, we apply the SF method to the atmospheric-resonance perturbation theory to uncover the 1-3 state relabeling symmetries. The pure 1-3 state symmetry takes the unique position that it is practically impossible to formulate in vacuum under the conventional choice of the flavor mixing matrix. In contrast, our SF method produces the sixteen 1-3 state exchange symmetries in matter. The relationship between the symmetries in the original (vacuum plus matter) Hamiltonian and the ones in the diagonalized system is discussed.

    hep-phEPJC(2021)·6 citations
19. 19*

    Hybrid high-energy/collinear factorization in a heavy-light dijets system reaction

    Andrèe Dafne Bolognino🇮🇹 · Francesco Giovanni Celiberto🇮🇹 · Michael Fucilla🇮🇹 · Dmitry Yu. Ivanov🇷🇺 · Alessandro Papa🇮🇹

    We propose the inclusive hadroproduction of a heavy-light dijet system, as a new channel for the investigation of high energy QCD. We build up a hybrid factorization that incorporates a partial next-to-leading BFKL resummation inside the standard collinear description of observables. We present a detailed analysis of different observables: cross-section summed over azimuthal angles and differential in rapidity and azimuthal distribution. The stability that these distributions show under higher-order corrections motivates our interest in future studies, doable at new generation colliding machines.

    hep-phSciPost Phys.Proc.(2022)·24 citations
20. 20*

    Complete One-loop Matching of the Type-I Seesaw Model onto the Standard Model Effective Field Theory

    Di Zhang🇨🇳 · Shun Zhou🇨🇳

    In this paper, we accomplish the complete one-loop matching of the type-I seesaw model onto the Standard Model Effective Field Theory (SMEFT), by integrating out three heavy Majorana neutrinos with the functional approach. It turns out that only 31 dimension-six operators (barring flavor structures and Hermitian conjugates) in the Warsaw basis of the SMEFT can be obtained, and most of them appear at the one-loop level. The Wilson coefficients of these 31 dimension-six operators are computed up to $\mathcal{O}\left(M^{-2}\right)$ with $M$ being the mass scale of heavy Majorana neutrinos. As the effects of heavy Majorana neutrinos are encoded in the Wilson coefficients of these higher-dimensional operators, a complete one-loop matching is useful to explore the low-energy phenomenological consequences of the type-I seesaw model. In addition, the threshold corrections to the couplings in the Standard Model and to the coefficient of the dimension-five operator are also discussed.

    hep-phhep-exJHEP(2021)·62 citations
21. 21*

    Semi-inclusive lepto-production of hidden-charm exotic hadrons

    Zhi Yang🇨🇳 · Feng-Kun Guo🇨🇳

    We investigate the semi-inclusive production of hidden-charm exotic states, including $X(3872)$, $Z_c$, $Z_{cs}$ and the pentaquark $P_c$ states, in lepton-proton scattering processes. These hadrons are close to the thresholds of a pair of charm and anticharm hadrons, and are assumed to have hadronic molecular structure as their main components. In order to give order-of-magnitude estimates of the cross sections, we use Pythia to simulate the short-distance productions of the constituent hadrons, which then rescatter to form the exotic hadrons. The estimates for the $X(3872)$ and $Z_c(3900{)}^{\pm }$ are not in conflict with the upper limits measured at the COMPASS experiment for the exclusive photoproduction process. The results here indicate that the considered hidden-charm states can be copiously produced at the proposed electron-ion colliders EicC and US-EIC.

    hep-phhep-exCPC(2021)·16 citations
22. 22*

    On the absence of shock waves and vacuum birefringence in Born--Infeld electrodynamics

    Hedvika Kadlecová🇨🇿

    We study the interaction of two counter-propagating electromagnetic waves in vacuum in the Born-Infeld electrodynamics. First we investigate the Born case for linearly polarized beams, $\mathbf{E}\cdot \mathbf{B}=0$, i. e. ${\mathfrak{G}}^2=0$ (crossed field configuration), which is identical for Born-Infeld and Born electrodynamics; subsequently we study the general Born-Infeld case for beams which are nonlinearly polarized, ${\mathfrak{G}}^2\ne 0$. In both cases, we show that the nonlinear field equations decouple using self-similar solutions and investigate the shock wave formation. We show that the only nonlinear solutions are exceptional travelling wave solutions which propagate with constant speed and which do not turn into shocks for our approximation. We obtain two types of exceptional wave solutions, then we numerically analyze which phase velocities correspond to the counter- or co-propagating beams and subsequently we determine the direction of propagation of the exceptional waves.

    hep-phphysics.plasm-phquant-phJ.Math.Phys.(2024)·8 citations
23. 23*

    Spinless mesons and glueballs mixing patterns in SU(3) flavor limit

    Amir H. Fariborz🇺🇸 · Mars Lyukova🇺🇸

    We present a detailed study of the interactions among scalar and pseudoscalar mesons and glueballs within the framework of the generalized linear sigma model in the SU(3) flavor limit. The basis of our approach is to develop a global understanding of light scalar and pseudoscalar mesons (up to around 2 GeV) and thereby explore the underlying mixings among composite quark matter fields and glueballs. The chiral sector of the Lagrangian is formulated in terms of two chiral nonets representing quark-antiquarks and tetraquarks (in the leading order, this sector contains terms with eight or fewer number of quak or antiquark lines). The Lagrangian also contains a sector that represents scalar and pseudoscalar glueballs and their interactions with the matter chiral fields, in a manner that the axial and trace anomalies of QCD are exactly realized. In this construct, the model has two scalar octets and two pdeudoscalar octets (each a linear combination of two- and four-quark components), as well as three scalar SU(3) singlets and three pseudoscalar SU(3) singlets (each a linear combination of two- and four-quark components as well as a glueball component). With the inputs of the experimental masses of $a_0(980)$, $a_0(1450)$, and the masses of $\pi (137)$, $\pi (1300)$ and their decay constants, we perform an extensive numerical simulation to determine the boundaries of the parameter space of the model. We further incorporate experimental data on the mass spectrum of eta states as well as on several decay widths and decay ratios of $f_0$ states to zoom in on the parameter space and make predictions for the substructure of pseudoscalar and scalar SU(3) octets and singlets as well as for the pseudoscalar and scalar glueball masses. We find the scalar and pseudoscalar glueball masses around 1.6 and 2.0 GeV, respectively.

    hep-phhep-exhep-latnucl-ex+1NPA(2021)·7 citations
24. 24*

    $CP$ asymmetry in the angular distributions of $\tau \to K_S\pi {\nu }_{\tau }$ decays -- II: general effective field theory analysis

    Feng-Zhi Chen🇨🇳 · Xin-Qiang Li🇨🇳 · Shi-Can Peng🇨🇳 · Ya-Dong Yang🇨🇳 · Hong-Hao Zhang🇨🇳

    We proceed to study the $CP$ asymmetry in the angular distributions of $\tau \to K_S\pi {\nu }_{\tau }$ decays within a general effective field theory framework including four-fermion operators up to dimension-six. It is found that, besides the commonly considered scalar-vector interference, the tensor-scalar interference can also produce a non-zero $CP$ asymmetry in the angular distributions. Bounds on the effective couplings of the non-standard scalar and tensor interactions are obtained under the combined constraints from the measured $CP$ asymmetries and the branching ratio of ${\tau }^{-}\to K_S{\pi }^{-}{\nu }_{\tau }$ decay, with $\mathrm{Im}[{\widehat{ϵ}}_S]=-0.008\pm 0.027$ and $\mathrm{Im}[{\widehat{ϵ}}_T]=0.03\pm 0.12$, at the scale ${\mu }_{\tau }=2\mathrm{GeV}$ in the $\overline{\mathrm{MS}}$ scheme. Using the best-fit values, we also find that the distributions of the $CP$ asymmetries can deviate significantly from the SM expectation in almost the whole $K\pi$ invariant-mass region. Nevertheless, the current bounds are still plagued by large experimental uncertainties, but will be improved with more precise measurements from Belle II as well as the proposed Tera-Z and STCF facilities. Assuming further that the non-standard scalar and tensor interactions originate from a weakly-coupled heavy new physics well above the electroweak scale, the $SU(2{)}_L$ invariance of the resulting SMEFT Lagrangian would indicate that very strong limits on $\mathrm{Im}[{\widehat{ϵ}}_S]$ and $\mathrm{Im}[{\widehat{ϵ}}_T]$ could also be obtained from the neutron electric dipole moment and the $D^0-{\bar{D}}^0$ mixing. With the bounds from these processes taken into account, it is then found that, unless there exist extraordinary cancellations between the new physics contributions, neither the scalar nor the tensor interaction can produce any significant effects on the $CP$ asymmetries in the processes considered.

    hep-phhep-exJHEP(2022)·28 citations
25. 25*

    Møller scattering at NNLO

    Pulak Banerjee🇨🇭 · Tim Engel🇨🇭 · Nicolas Schalch🇨🇭 · Adrian Signer🇨🇭 · Yannick Ulrich🇬🇧

    We present a calculation of the full set of next-to-next-to-leading-order QED corrections to unpolarised Møller scattering. This encompasses photonic, leptonic, and non-perturbative hadronic corrections and includes electron mass effects as well as hard photon radiation. The corresponding matrix elements are implemented in the Monte Carlo framework McMule allowing for the computation of fully-differential observables. As a first application we show results tailored to the kinematics and detector design of the PRad II experiment where a high-precision theory prediction for Møller scattering is required to achieve the targeted precision. We observe that the corrections become essential to reliably calculate the corresponding differential distributions especially in regions where the leading-order contribution is absent.

    hep-phhep-exPRD(2022)·25 citations
26. 26*

    Gluon saturation in proton and its contribution to single inclusive soft gluon production in high energy proton-nucleus collisions

    Ming Li🇺🇸

    The leading order single inclusive soft gluon production in high energy proton-nucleus (pA) collisions has been studied by various approaches for more than two decades. The first correction due to the gluon saturation in proton was analytically attempted recently through a diagrammatic approach in which only partial results were obtained. An important feature of the first saturation correction is that it includes both initial state and final state interactions. In this paper, we present the complete result derived from the Color Glass Condensate framework. Our approach is to analytically solve the classical Yang-Mills equations in the dilute-dense regime and then use the Lehmann-Symanzik-Zimmermann (LSZ) reduction formula to obtain gluon production from classical gluon fields.

    hep-phSciPost Phys.Proc.(2022)·0 citations
27. 27*

    Anomaly Ratio Distributions of Hadronic Axion Models with Multiple Heavy Quarks

    Vaisakh Plakkot🇩🇪 · Sebastian Hoof🇩🇪

    We consider hadronic axion models that extend the Standard Model by one complex scalar field and one or more new heavy quarks, i.e. $N_{\mathcal{Q}}\ge 1$. We review previously suggested selection criteria as well as categorize and catalog all possible models for $N_{\mathcal{Q}}\le 9$. In particular, allowing for $N_{\mathcal{Q}}>1$ can introduce models that spoil the axion solution of the strong CP problem. Demanding that Landau poles do not appear below some energy scale limits the number of preferred models to a finite number. For our choice of criteria, we find that $N_{\mathcal{Q}}\le 28$ and only 820 different anomaly ratios $E/N$ exist (443 when considering additive representations, 12 when all new quarks transform under the same representation). We analyze the ensuing $E/N$ distributions, which can be used to construct informative priors on the axion-photon coupling. The hadronic axion model band may be defined as the central region of one of these distributions, and we show how the band for equally probable, preferred models compares to present and future experimental constraints.

    hep-phPRD(2021)·38 citations
28. 28*

    Unsupervised Hadronic SUEP at the LHC

    Jared Barron🇨🇦 · David Curtin🇨🇦 · Gregor Kasieczka🇩🇪 · Tilman Plehn🇩🇪 · Aris Spourdalakis🇨🇦

    Confining dark sectors with pseudo-conformal dynamics produce SUEP, or Soft Unclustered Energy Patterns, at colliders: isotropic dark hadrons with soft and democratic energies. We target the experimental nightmare scenario, SUEPs in exotic Higgs decays, where all dark hadrons decay promptly to SM hadrons. First, we identify three promising observables, the charged particle multiplicity, the event ring isotropy, and the matrix of geometric distances between charged tracks. Their patterns can be exploited through a cut-and-count search, supervised machine learning, or an unsupervised autoencoder. We find that the HL-LHC will probe exotic Higgs branching ratios at the per-cent level, even without a detailed knowledge of the signal features. Our techniques can be applied to other SUEP searches, especially the unsupervised strategy, which is independent of overly specific model assumptions and the corresponding precision simulations.

    hep-phhep-exJHEP(2021)·42 citations
29. 29*

    Searching for pseudo Nambu-Goldstone boson dark matter production in association with top quarks

    Ulrich Haisch🇩🇪 · Giacomo Polesello🇮🇹 · Stefan Schulte🇩🇪

    Pseudo Nambu-Goldstone bosons (pNGBs) are attractive dark matter (DM) candidates, since they couple to the Standard Model (SM) predominantly through derivative interactions. Thereby they naturally evade the strong existing limits inferred from DM direct detection experiments. Working in an effective field theory that includes both derivative and non-derivative DM-SM operators, we perform a detailed phenomenological study of the Large Hadron Collider reach for pNGB DM production in association with top quarks. Drawing on motivated benchmark scenarios as examples, we compare our results to other collider limits as well as the constraints imposed by DM (in)direct detection experiments and the relic abundance. We furthermore explore implications on the viable parameter space of pNGB DM. In particular, we demonstrate that DM direct detection experiments become sensitive to many pNGB DM realisations once loop-induced interactions are taken into account. The search strategies and pNGB DM benchmark models that we discuss can serve as a starting point for dedicated experimental analyses by the ATLAS and the CMS collaborations.

    hep-phhep-exJHEP(2021)·18 citations
30. 30*

    BSM Master Formula for ${\epsilon }^{\prime }/\epsilon$ in the WET Basis at NLO in QCD

    Jason Aebischer🇺🇸 · Christoph Bobeth🇩🇪 · Andrzej J. Buras🇩🇪 · Jacky Kumar🇩🇪

    As an important step towards a complete next-to-leading order (NLO) QCD analysis of the ratio ${\epsilon }^{\prime }/\epsilon$ within the Standard Model Effective Field Theory (SMEFT), we present for the first time the NLO master formula for the BSM part of this ratio expressed in terms of the Wilson coefficients of all contributing operators evaluated at the electroweak scale. To this end we use the common Weak Effective Theory (WET) basis (the so-called JMS basis) for which tree-level and one-loop matching to the SMEFT are already known. The relevant hadronic matrix elements of BSM operators at the electroweak scale are taken from Dual QCD approach and the SM ones from lattice QCD. It includes the renormalization group evolution and quark-flavour threshold effects at NLO in QCD from hadronic scales, at which these matrix elements have been calculated, to the electroweak scale.

    hep-phhep-exhep-latJHEP(2021)·27 citations
31. 31*

    Supernova bound on Axion-Like Particles coupled with electrons

    Giuseppe Lucente🇮🇹 · Pierluca Carenza🇮🇹

    Axion-Like Particles (ALPs) coupled with electrons would be produced in a Supernova (SN) via electron-proton bremsstrahlung and electron-positron fusion. We evaluate the ALP emissivity from these processes by taking into account the ALP mass and thermal effects on electrons in the strongly degenerate and relativistic SN plasma. Using a state-of-the-art SN simulation, we evaluate the SN 1987A cooling bound on ALPs for masses in the range $1-200$ MeV, which excludes currently unprobed regions down to $g_{ae}\sim 2.5\times 10^{-10}$ at $m_a\sim 120$ MeV.

    hep-phastro-ph.HEPRD(2021)·75 citations
32. 32*

    Three-dimensional imaging in nuclei

    Mishary Alrashed🇺🇸 · Daniele Anderle🇨🇳 · Zhong-Bo Kang🇺🇸 · John Terry🇺🇸 · Hongxi Xing🇨🇳

    We perform the first simultaneous global QCD extraction of the transverse momentum dependent (TMD) parton distribution functions and the TMD fragmentation functions in nuclei. We have considered the world set of data from semi-inclusive electron-nucleus deep inelastic scattering and Drell-Yan di-lepton production. In total, this data set consists of 126 data points from HERMES, Fermilab, RHIC and LHC. Working at next-to-leading order and next-to-next-to-leading logarithmic accuracy, we achieve a ${\chi }^2/dof=1.045$. In this analysis, we quantify the broadening of TMDs in nuclei comparing with those in free nucleons for the first time. We also make predictions for the ongoing JLab 12 GeV program and future EIC measurements.

    hep-phhep-exnucl-exnucl-thPRL(2022)·33 citations
33. 33*

    Vector-Like top quark production via a chromo-magnetic moment at the LHC

    Alexander Belyaev🇬🇧 · R. Sekhar Chivukula🇺🇸 · Benjamin Fuks🇫🇷 · Elizabeth H. Simmons🇺🇸 · Xing Wang🇺🇸

    Theories which provide a dynamical explanation for the large top-quark mass often include TeV-scale vector-like top-quark and bottom-quark partner states which can be potentially discovered at the LHC. These states are currently probed through model-independent searches for pair-production via gluon fusion, as well as through model-dependent complementary electroweak single production. In this paper we study the potential to extend those searches for the partners of the third-generation Standard Model quarks on the basis of their expected chromomagnetic interactions. We discuss how current searches for "excited" bottom-quarks produced via $b$-gluon fusion through chromomagnetic interactions are relevant, and provide significant constraints. We then explore the region of the parameter space in which the bottom-quark partner is heavier than the top-quark partner, in which case the top-partner can be primarily produced via the decay of the bottom-partner. Next, we probe the potential of the production of a single top-quark partner in association with an ordinary top-quark by gluon-fusion. Kinematically these two new processes are similar, and they yield the production of a heavy top partner and a lighter Standard Model state, a pattern which allows for the rejection of the associated dominant Standard Model backgrounds. We examine the sensitivity of these modes in the case where the top-partner subsequently decays to a Higgs boson and an ordinary top-quark, and we demonstrate that these new channels have the potential of extending and complementing the conventional strategies at LHC run III and at the high-luminosity phase of the LHC. In this last case, we find that partner masses that range up to about 3 TeV can be reached. This substantially expands the expected mass reach for these new states, including regions of parameter space that are inaccessible by traditional searches.

    hep-phhep-exPRD(2021)·19 citations
34. 34*

    Implications of Quantum Gravity for Dark Matter

    Xavier Calmet🇬🇧 · Folkert Kuipers🇬🇧

    In this essay we show that quantum gravity and the spin-statistics theorem have very interesting consequences for dark matter candidates. Quantum gravity can lead to fifth force type interactions that lead to a lower bound on the masses of bosonic candidates. In the case of fermions, the spin-statistics theorem leads to a lower bound on fermion masses. For both bosonic and fermionic dark matter candidates, quantum gravity leads to a decay of dark matter particles. A comparison of their lifetime with the age of the universe leads to an upper bound on their masses. For singlet scalar dark matter fields, we find $10^{-3}\mathrm{eV}\lesssim m\lesssim 10^7\mathrm{eV}$.

    hep-phhep-thInt.J.Mod.Phys.D(2021)·11 citations
35. 35*

    Nuclear and electronic contributions to Coulomb correction for Moliere screening angle

    M.V. Bondarenco🇺🇦

    The Coulomb correction (difference from the 1st Born approximation) to the Molière screening angle in multiple Coulomb scattering theory is evaluated with the allowance for inelastic contribution. The controversy between dominance of close- or remote-collision contributions to Coulomb correction is discussed. For scattering centres represented by a Coulomb potential with a generic (not necessarily spherically symmetric) creening function, the Coulomb correction is proven to be screening-independent, by virtue of the eikonal phase cancellation in regions distant from the Coulomb singularity. Treating the atom %more self-consistently, as an assembly of pointlike electrons and the nucleus, and summing the scattering probability over all the final atom states, it is shown that besides the Coulomb correction due to close encounters of the incident charged particle with atomic nuclei, there are similar corrections due to close encounters with atomic electrons (an analog of Bloch correction). For low $Z\ne 1$ the latter contribution can reach $\sim 25\%$, but its observation is partly obscured by multiple scattering effects.

    ↳ physics.atom-phhep-phquant-ph0 citations
36. 36*

    Thermalization of Gauge Theories from their Entanglement Spectrum

    Niklas Mueller🇺🇸 · Torsten V. Zache🇦🇹 · Robert Ott🇩🇪

    Using dual theories embedded into a larger unphysical Hilbert space along entanglement cuts, we study the Entanglement Structure of ${\mathbf{Z}}_2$ lattice gauge theory in $(2+1)$ spacetime dimensions. We demonstrate Li and Haldane's conjecture, and show consistency of the Entanglement Hamiltonian with the Bisognano-Wichmann theorem. Studying non-equilibrium dynamics after a quench, we provide an extensive description of thermalization in ${\mathbf{Z}}_2$ gauge theory which proceeds in a characteristic sequence: Maximization of the Schmidt rank and spreading of level repulsion at early times, self-similar evolution with scaling coefficients $\alpha =0.8\pm 0.2$ and $\beta =0.0\pm 0.1$ at intermediate times, and finally thermal saturation of the von Neumann entropy.

    ↳ quant-phhep-lathep-phPRL(2022)·70 citations
37. 37*

    Dark Matter Neutrino Scattering in the Galactic Center with IceCube

    Adam McMullen🇨🇦 · Aaron Vincent🇨🇦 · Carlos Arguelles🇺🇸 · Austin Schneider (for the IceCube Collaboration)🇺🇸

    While there is evidence for the existence of dark matter, its properties have yet to be discovered. Simultaneously, the nature of high-energy astrophysical neutrinos detected by IceCube remains unresolved. If dark matter and neutrinos are coupled to each other, they may exhibit a non-zero elastic scattering cross section. Such an interaction between an isotropic extragalactic neutrino flux and dark matter would be concentrated in the Galactic Centre, where the dark matter column density is greatest. This scattering would attenuate the flux of high-energy neutrinos, which could be observed in IceCube. Using the seven-year Medium Energy Starting Events sample, we perform an unbinned likelihood analysis, searching for a signal based on a possible DM-neutrino interaction scenario. We search for a suppression of the high-energy astrophysical neutrino flux in the direction of the Galactic Centre, and compare these constraints to complementary low-energy information from large scale structure surveys and the cosmic microwave background.

    ↳ astro-ph.HEhep-phJINST(2021)·10 citations
38. 38*

    Mori-Zwanzig formalism for general relativity: a new approach to the averaging problem

    Michael te Vrugt🇩🇪 · Sabine Hossenfelder🇩🇪 · Raphael Wittkowski🇩🇪

    Cosmology relies on a coarse-grained description of the universe, assumed to be valid on large length scales. However, the nonlinearity of general relativity makes coarse-graining extremely difficult. We here address this problem by extending the Mori-Zwanzig projection operator formalism, a highly successful coarse-graining method from statistical mechanics, towards general relativity. Using the Buchert equations, we derive a new dynamic equation for the Hubble parameter which captures the effects of averaging through a memory function. This gives an empirical prediction for the cosmic jerk.

    ↳ gr-qcastro-ph.COcond-mat.stat-mechhep-phPRL(2021)·10 citations
39. 39*

    Emergent Cosmology from Matrix Theory

    Suddhasattwa Brahma🇨🇦 · Robert Brandenberger🇨🇦 · Samuel Laliberte🇨🇦

    Matrix theory is a proposed non-perturbative definition of superstring theory in which space is emergent. We begin a study of cosmology in the context of matrix theory. Specifically, we show that matrix theory can lead to an emergent non-singular cosmology which, at late times, can be described by an expanding phase of Standard Big Bang cosmology. The horizon problem of Standard Big Bang cosmology is automatically solved. We show that thermal fluctuations in the emergent phase source an approximately scale-invariant spectrum of cosmological perturbations and a scale-invariant spectrum of gravitational waves. Hence, it appears that matrix theory can lead to a successful scenario for the origin of perturbations responsible for the currently observed structure in the universe while providing a consistent UV-complete description.

    ↳ hep-thastro-ph.COgr-qchep-phJHEP(2022)·53 citations
40. 40*

    A Data-Directed Paradigm for BSM searches: the bump-hunting example

    Sergey Volkovich🇮🇱 · Federico De Vito Halevy🇮🇱 · Shikma Bressler🇮🇱

    We propose a data-directed paradigm (DDP) to search for new physics. Focusing on the data without using simulations, exclusive selections which exhibit significant deviations from known properties of the standard model can be identified efficiently and marked for further study. Different properties can be exploited with the DDP. Here, the paradigm is demonstrated by combining the promising potential of neural networks (NN) with the common bump-hunting approach. Using the NN, the resource-consuming tasks of background and systematic uncertainty estimation are avoided, allowing rapid testing of many final states with only a minor degradation in the sensitivity to bumps relative to standard analysis methods.

    ↳ hep-exhep-phEPJC(2022)·24 citations
41. 41*

    Scaling solutions of wiggly cosmic strings

    A. R. R. Almeida🇵🇹 · C. J. A. P. Martins🇵🇹

    Cosmic strings may have formed in the early universe due to the Kibble mechanism. While string networks are usually modeled as being of Nambu-Goto type, this description is understood to be a convenient approximation, which neglects the typically expected presence of additional degrees of freedom on the string worldsheet. Previous simulations of cosmic strings in expanding universes have established beyond doubt the existence of a significant amount of short-wavelength propagation modes (commonly called wiggles) on the strings, and a wiggly string extension of the canonical velocity-dependent one-scale model has been recently developed. Here we improve the physical interpretation of this model, by studying the possible asymptotic scaling solutions of this model, and in particular how they are affected by the expansion of the universe and the available energy loss or transfer mechanisms -- e.g., the production of loops and wiggles. In addition to the Nambu-Goto solution, to which the wiggly model reduces in the appropriate limit, we find that there are also solutions where the amount of wiggliness can grow as the network evolves or, for specific expansion rates, become a constant. Our results show that full scaling of the network, including the wiggliness, is much more likely in the matter era than in the radiation era, which is in agreement with numerical simulation results.

    ↳ astro-ph.COgr-qchep-phPRD(2021)·11 citations
42. 42*

    Nuclear Effective Field Theories: Reverberations of the early days

    U. van Kolck🇫🇷

    Effective field theories are recognized nowadays as the framework to describe low-energy nuclear structure and reactions consistently with the underlying theory of the strong interactions, QCD. It was not always so. As we celebrate the 30 years of the first publications, I collect here some memories from those early days. I also discuss some of the key issues that were raised back then and, despite all progress, are still with us. Dedicated to the memory of Steven Weinberg, whose ideas will not die, wherever they may lead.

    ↳ nucl-thhep-phphysics.hist-phFew Body Syst.(2021)·16 citations
43. 43*

    Covariant Chiral Kinetic Equation in Non-Abelian Gauge field from "covariant gradient expansion"

    Xiao-Li Luo🇨🇳 · Jian-Hua Gao🇨🇳

    We derive the chiral kinetic equation in 8 dimensional phase space in non-Abelian $SU(N)$ gauge field within the Wigner function formalism. By using the "covariant gradient expansion", we disentangle the Wigner equations in four-vector space up to the first order and find that only the time-like component of the chiral Wigner function is independent while other components can be explicit derivative. After further decomposing the Wigner function or equations in color space, we present the non-Abelian covariant chiral kinetic equation for the color singlet and multiplet phase-space distribution functions. These phase-space distribution functions have non-trivial Lorentz transformation rules when we define them in different reference frames. The chiral anomaly from non-Abelian gauge field arises naturally from the Berry monopole in Euclidian momentum space in the vacuum or Dirac sea contribution. The anomalous currents as non-Abelian counterparts of chiral magnetic effect and chiral vortical effect have also been derived from the non-Abelian chiral kinetic equation.

    ↳ hep-thhep-phnucl-thJHEP(2021)·17 citations
44. 44*

    Analytic solutions of relativistic dissipative spin hydrodynamics with Bjorken expansion

    Dong-Lin Wang🇨🇳 · Shuo Fang🇨🇳 · Shi Pu🇨🇳

    We have studied analytically the longitudinally boost-invariant motion of a relativistic dissipative fluid with spin. We have derived the analytic solutions of spin density and spin chemical potential as a function of proper time $\tau$ in the presence of viscous tensor and the second order relaxation time corrections for spin. Interestingly, analogous to the ordinary particle number density and chemical potential, we find that the spin density and spin chemical potential decay as $\sim {\tau }^{-1}$ and $\sim {\tau }^{-1/3}$, respectively. It implies that the initial spin density may not survive at the freezeout hyper-surface. These solutions can serve both to gain insight on the dynamics of spin polarization in relativistic heavy-ion collisions and as testbeds for further numerical codes.

    ↳ nucl-thhep-phPRD(2021)·71 citations
45. 45*

    Probing criticality with deep learning in relativistic heavy-ion collisions

    Yige Huang🇨🇳 · Long-Gang Pang🇨🇳 · Xiaofeng Luo🇨🇳 · Xin-Nian Wang🇨🇳

    Systems with different interactions could develop the same critical behaviour due to the underlying symmetry and universality. Using this principle of universality, we can embed critical correlations modeled on the 3D Ising model into the simulated data of heavy-ion collisions, hiding weak signals of a few inter-particle correlations within a large particle cloud. Employing a point cloud network with dynamical edge convolution, we are able to identify events with critical fluctuations through supervised learning, and pick out a large fraction of signal particles used for decision-making in each single event.

    ↳ nucl-thhep-exhep-phnucl-exPLB(2022)·20 citations
46. 46*

    First direct lattice calculation of the chiral perturbation theory low-energy constant ${\ell }_7$

    R. Frezzotti🇮🇹 · G. Gagliardi🇮🇹 · V. Lubicz🇮🇹 · G. Martinelli🇮🇹 · F. Sanfilippo🇮🇹 · S. Simula🇮🇹

    We evaluate by means of lattice QCD calculations the low-energy constant ${\ell }_7$ which parametrizes strong isospin effects at NLO in $\mathrm{SU}(2)$ chiral perturbation theory. Among all low-energy constants at NLO, ${\ell }_7$ is the one known less precisely, and its uncertainty is currently larger than $50\%$. Our strategy is based on the RM123 approach in which the lattice path-integral is expanded in powers of the isospin breaking parameter $\Delta m=(m_d-m_u)/2$. In order to evaluate the relevant lattice correlators we make use of the recently proposed rotated twisted-mass (RTM) scheme. Within the RM123 approach, it is possible to cleanly extract the value of ${\ell }_7$ from either the pion mass splitting $M_{{\pi }^{+}}-M_{{\pi }^0}$ induced by strong isospin breaking at order $\mathcal{O}\left((\Delta m{)}^2\right)$ (mass method), or from the coupling of the neutral pion ${\pi }^0$ to the isoscalar operator $\left(\bar{u}{\gamma }_{5}u+\bar{d}{\gamma }_{5}d\right)/\sqrt{2}$ at order $\mathcal{O}(\Delta m)$ (matrix element method). In this pilot study we limit the analysis to a single ensemble generated by the Extended Twisted Mass Collaboration (ETMC) with $N_f=2+1+1$ dynamical quark flavours, which corresponds to a lattice spacing $a\simeq 0.095\mathrm{fm}$ and to a pion mass $M_{\pi }\simeq 260\mathrm{MeV}$. We find that the matrix element method outperforms the mass method in terms of resulting statistical accuracy. Our determination, ${\ell }_7=2.5(1.4)\times 10^{-3}$, is in agreement and improves previous calculations.

    ↳ hep-lathep-phPRD(2021)·11 citations
47. 47*

    Lattice QCD calculation of the Collins-Soper kernel from quasi TMDPDFs

    Phiala Shanahan🇺🇸 · Michael Wagman🇺🇸 · Yong Zhao🇺🇸

    This work presents a lattice quantum chromodynamics (QCD) calculation of the nonperturbative Collins-Soper kernel, which describes the rapidity evolution of quark transverse-momentum-dependent parton distribution functions. The kernel is extracted at transverse momentum scales in the range 400 MeV $<q_T<1.7$ GeV in a calculation with dynamical fermions and quark masses corresponding to a larger-than-physical pion mass, $m_{\pi }=538(1)$ MeV. It is found that different approaches to extract the Collins-Soper kernel from the same underlying lattice QCD matrix elements yield significantly different results and uncertainty estimates, revealing that power corrections, such as those associated with higher-twist effects, and perturbative matching between quasi and light-cone beam functions, cannot be neglected.

    ↳ hep-lathep-phnucl-thPRD(2021)·99 citations
48. 48*

    4D effective action from non-Abelian DBI action with magnetic flux background

    Yoshihiko Abe🇯🇵 · Tetsutaro Higaki🇯🇵 · Tatsuo Kobayashi🇯🇵 · Shintaro Takada🇯🇵 · Rei Takahashi🇯🇵

    We study a systematic derivation of four dimensional $\mathcal{N}=1$ supersymmetric effective theory from ten dimensional non-Abelian Dirac-Born-Infeld action compactified on a six dimensional torus with magnetic fluxes on the D-branes. We find a new type of matter Kähler metric while gauge kinetic function and superpotential are consistent with previous studies. For the ten dimensional action, we use a symmetrized trace prescription and focus on the bosonic part up to $\mathcal{O}(F^4)$. In the presence of the supersymmetry, four dimensional chiral fermions can be obtained via index theorem. The new matter Kähler metric is independent of flavor but depends on the fluxes, 4D dilaton, Kähler moduli and complex structure moduli, and will be always positive definite if an induced Ramond-Ramond charge of the D-branes on which matters are living are positive. We read the superpotential from an F-term scalar quartic interaction derived from the ten dimensional action and the contribution of the new matter Kähler metric to the scalar potential which we derive turns out to be consistent with the supergravity formulation.

    ↳ hep-thhep-phPRD(2021)·7 citations
49. 49*

    Probing the in-medium $P_T$-broadening by $\gamma$+HF angular de-correlations

    Sa Wang🇨🇳 · Jin-Wen Kang🇨🇳 · Wei Dai🇨🇳 · Ben-Wei Zhang🇨🇳 · Enke Wang🇨🇳

    Angular correlations between vector boson and heavy flavors~(HF) are potentially new effective tools to gain insight into the partonic interactions in the quark-gluon plasma (QGP). In this paper, we present the theoretical study of the azimuthal angular de-correlations of $\gamma +$HF in nucleus-nucleus collisions as a new probe of the in-medium $P_T$-broadening effect. The initial production of $\gamma +$HF in p+p is generated by SHERPA which matches the next-to-leading hard processes with parton shower. The in-medium heavy quark evolution is implemented by a Monte Carlo Langevin simulation, which takes into account the collisional and radiative energy loss. We observe considerable suppression at $\Delta {\varphi }_{\gamma D}\sim \pi$ and enhancement at $\Delta {\varphi }_{\gamma D}<2.8$ in $\gamma +$D azimuthal angular distribution in $0-10\%$ Pb+Pb collisions at $\sqrt{s_{NN}}=$5.02 TeV compared to the p+p baseline, which indicates evident in-medium $P_T$-broadening of charm quarks. We also find that the overall modification patterns of $\gamma +$D angular distribution are sensitive to the selection cut of D meson $p_T$. Furthermore, by constructing the 2D ($x_J^{\gamma D},\Delta {\varphi }_{\gamma D}$) correlation diagram, it's possible to display the respective impacts of the two aspects of jet quenching, energy loss and $P_T$-broadening, on the final-state $\gamma +$D observable simultaneously. Additionally, we find weaker angular de-correlations of $\gamma +$B compared to $\gamma +$D which may be helpful to understand the mass hierarchy in heavy-ion collisions. Finally, the nuclear modification of $\Delta {\varphi }_{\gamma D}$ distributions in central $0-10\%$ Au+Au collisions at RHIC energy is provided for completeness.

    ↳ nucl-thhep-phEur.Phys.J.A 58 (2022) 7, 135·14 citations
50. 50*

    Mimetic Tensor-Vector-Scalar Cosmology: Incorporating Dark Matter, Dark Energy and Stiff Matter

    David Benisty🇬🇧 · Masud Chaichian🇫🇮 · Markku Oksanen🇫🇮

    Phenomenological implications of the Mimetic Tensor-Vector-Scalar theory (MiTeVeS) are studied. The theory is an extension of the vector field model of mimetic dark matter, where a scalar field is also incorporated, and it is known to be free from ghost instability. In the absence of interactions between the scalar field and the vector field, the obtained cosmological solution corresponds to the General theory of Relativity (GR) with a minimally-coupled scalar field. However, including an interaction term between the scalar field and the vector field yields interesting dynamics. There is a shift symmetry for the scalar field with a flat potential, and the conserved Noether current, which is associated with the symmetry, behaves as a dark matter component. Consequently, the solution contains a cosmological constant, dark matter and a stiff matter fluid. Breaking the shift symmetry with a non-flat potential gives a natural interaction between dark energy and dark matter.

    ↳ gr-qcastro-ph.COhep-phhep-thPhys.Dark Univ.(2023)·11 citations
51. 51*

    Yang-Mills at Strong vs. Weak Coupling: Renormalons, OPE And All That

    M. Shifman🇺🇸

    I discuss various situations in which perturbative expansions are used in Yang-Mills theories with asymptotic freedom and establish the limits of its applicability.

    ↳ hep-thhep-phEur.Phys.J.ST(2021)·5 citations
52. 52*

    Constraining spinning primordial black holes with global 21-cm signal

    Pravin Kumar Natwariya🇮🇳 · Alekha C. Nayak🇮🇳 · Tripurari Srivastava🇮🇳

    We study the upper projected bounds on the dark matter fraction in the form of the primordial black holes (PBHs) with a non-zero spin by using the absorption feature in the global 21-cm signal at redshift z ~ 17. The mass and spin are fundamental properties of a black hole, and they can substantially affect the evaporation rate of the black hole. The evaporating black hole can inject energy into the intergalactic medium and heat the gas. Subsequently, it can modify the absorption amplitude in the global 21-cm signal. Therefore, the absorption feature in the 21-cm signal can provide a robust bound on PBHs. We analyse the projected constraints on the dark matter fraction in the form of both spinning and non-spinning PBHs. The constraints are more stringent for spinning PBHs than non-spinning ones. We also compare these bounds with other observations and find the most stringent lower constraint on PBHs mass, which is allowed to constitute the entire dark matter to 6.7 x 10^17 g for extremal spinning PBHs.

    ↳ astro-ph.COhep-phMNRAS(2021)·32 citations
53. 53*

    Cosmological Constraints on Dark Matter Interactions with Ordinary Matter

    Manuel A. Buen-Abad🇺🇸 · Rouven Essig🇺🇸 · David McKeen🇨🇦 · Yi-Ming Zhong🇺🇸

    Dark matter interactions with electrons or protons during the early Universe leave imprints on the cosmic microwave background and the matter power spectrum, and can be probed through cosmological and astrophysical observations. These interactions lead to momentum and heat exchange between the ordinary and dark matter components, which in turn results in a transfer of pressure from the ordinary to the dark matter. We explore these interactions using a diverse suite of data: cosmic microwave background anisotropies, baryon acoustic oscillations, the Lyman-$\alpha$ forest, and the abundance of Milky-Way subhalos. We derive constraints using model-independent parameterizations of the dark matter--electron and dark matter--proton interaction cross sections and map these constraints onto concrete dark matter models. Our constraints are complementary to other probes of dark matter interactions with ordinary matter, such as direct detection, big bang nucleosynthesis, various astrophysical systems, and accelerator-based experiments. They exclude sufficiently large cross sections for a large range of dark matter masses, which cannot be accessed by direct-detection experiments due to the overburden from the Earth's atmosphere or crust.

    ↳ astro-ph.COhep-phPhys.Rept.(2022)·125 citations
54. 54*

    Observational constraints on dark matter scattering with electrons

    David Nguyen🇺🇸 · Dimple Sarnaaik🇺🇸 · Kimberly K. Boddy🇺🇸 · Ethan O. Nadler🇺🇸 · Vera Gluscevic🇺🇸

    We present new observational constraints on the elastic scattering of dark matter with electrons for dark matter masses between 10 keV and 1 TeV. We consider scenarios in which the momentum-transfer cross section has a power-law dependence on the relative particle velocity, with a power-law index $n\in \{-4,-2,0,2,4,6\}$. We search for evidence of dark matter scattering through its suppression of structure formation. Measurements of the cosmic microwave background temperature, polarization, and lensing anisotropy from \textit{Planck} 2018 data and of the Milky Way satellite abundance measurements from the Dark Energy Survey and Pan-STARRS1 show no evidence of interactions. We use these data sets to obtain upper limits on the scattering cross section, comparing them with exclusion bounds from electronic recoil data in direct detection experiments. Our results provide the strongest bounds available for dark matter--electron scattering derived from the distribution of matter in the Universe, extending down to sub-MeV dark matter masses, where current direct detection experiments lose sensitivity.

    ↳ astro-ph.COhep-phPRD(2021)·79 citations
55. 55*

    Searching for time-dependent high-energy neutrino emission from X-ray binaries with IceCube

    Qinrui Liu · Ali Kheirandish (for the IceCube Collaboration)

    X-ray binaries are long-standing source candidates of Galactic cosmic rays and neutrinos. The compact object in a binary system can be the site for cosmic-ray acceleration, while high-energy neutrinos can be produced by the interactions of cosmic rays in the jet of the compact object, the stellar wind, or the atmosphere of the companion star. We report a time-dependent study of high-energy neutrinos from X-ray binaries with IceCube using 7.5 years of muon neutrino data and X-ray observations. In the absence of significant correlation, we report upper limits on the neutrino fluxes from these sources and provide a comparison with theoretical predictions.

    ↳ astro-ph.HEhep-phPoS(2021)·2 citations
56. 56*

    A Fake Instability in String Inflation

    Michele Cicoli🇮🇹 · Veronica Guidetti🇩🇪 · Francesco Muia🇬🇧 · Francisco G. Pedro🇮🇹 · Gian Paolo Vacca🇮🇹

    In type IIB Fibre Inflation models the inflaton is a Kaehler modulus which is kinetically coupled to the corresponding axion. In this setup the curvature of the field space induces tachyonic isocurvature perturbations normal to the background inflationary trajectory. However we argue that the associated instability is unphysical since it is due to the use of ill-defined entropy variables. In fact, upon using the correct relative entropy perturbation, we show that in Fibre Inflation axionic isocurvature perturbations decay during inflation and the dynamics is essentially single-field.

    ↳ hep-thastro-ph.COgr-qchep-phClass.Quant.Grav.(2022)·9 citations
57. 57*

    Constraining dark matter annihilation with cosmic ray antiprotons using neural networks

    Felix Kahlhoefer🇩🇪 · Michael Korsmeier🇸🇪 · Michael Krämer🇩🇪 · Silvia Manconi🇩🇪 · Kathrin Nippel🇩🇪

    The interpretation of data from indirect detection experiments searching for dark matter annihilations requires computationally expensive simulations of cosmic-ray propagation. In this work we present a new method based on Recurrent Neural Networks that significantly accelerates simulations of secondary and dark matter Galactic cosmic ray antiprotons while achieving excellent accuracy. This approach allows for an efficient profiling or marginalisation over the nuisance parameters of a cosmic ray propagation model in order to perform parameter scans for a wide range of dark matter models. We identify importance sampling as particularly suitable for ensuring that the network is only evaluated in well-trained parameter regions. We present resulting constraints using the most recent AMS-02 antiproton data on several models of Weakly Interacting Massive Particles. The fully trained networks are released as DarkRayNet together with this work and achieve a speed-up of the runtime by at least two orders of magnitude compared to conventional approaches.

    ↳ astro-ph.HEcs.LGhep-phJCAP(2021)·27 citations
58. 58*

    Estimating Microscopic Nuclear Data by Compact Star Observations

    Balázs Endre Szigeti🇭🇺 · Gergely Gábor Barnaföldi🇭🇺 · Péter Pósfay🇭🇺 · Antal Jakovác🇭🇺

    We studied recent observation data of pulsar masses and radii of PSR J0740$+$6620, PSR J0348$+$0432, and PSR J1614$-$2230 from different measurements, based on the extended version of $\sigma$-$\omega$ model. Throughout our analysis, we assumed that these pulsars are maximal-mass compact stars, thus we applied the core approximation. Based on the linear relation between the microscopic and macroscopic parameters of compact stars evaluated by our model, we estimated the average Landau mass $m_L=752.46_{-42.5}^{+49.1}$ MeV and compressibility $K=261.7_{-28.0}^{+57.2}$ MeV.

    ↳ nucl-thastro-ph.HEhep-phEPJ Web Conf.(2022)·2 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.