Fri·Jun 23, 2023Friday·June 23, 2023

1. 01*

   Softening the UV without New Particles

   Anson Hook🇺🇸 · Riccardo Rattazzi🇨🇭

   We explore an odd class of QFTs where a hierarchy problem is resolved with new dynamics as opposed to new particles. The essential element of our construction is a $U(1)$ pseudo-NG boson with symmetry breaking interactions all characterized by a large number $N$ of units of the fundamental charge. In the resulting effective theory, quantum corrections, like those to the effective potential and mass, which are normally power divergent and saturated at the UV cut-off, are instead saturated at a much lower scale. This critical scale, which does not involve any new particle, corresponds to the onset of unsuppressed multiparticle production in scattering processes. Remarkably this all happens within the tractable domain of weak coupling. Terms involving arbitrarily high powers of the Goldstone field must however be taken into account. In particular, a truncation to the renormalizable part of the effective Lagrangian would completely miss the physics.

   hep-phhep-thPRD(2023)·11 citations
2. 02*

   Tree-level UV completions for $N_R$SMEFT $d=6$ and $d=7$ operators

   Rebeca Beltrán🇪🇸 · Ricardo Cepedello🇩🇪 · Martin Hirsch🇪🇸

   We study ultra-violet completions for operators in standard model effective field theory extended with right-handed neutrinos ($N_R$SMEFT). Using a diagrammatic method, we generate systematically lists of possible tree-level completions involving scalars, fermions or vectors for all operators at $d=6$ and $d=7$, which contain at least one right-handed neutrino. We compare our lists of possible UV models to the ones found for pure SMEFT. We also discuss how the observation of LNV processes via $N_R$SMEFT operators at the LHC can be related to Majorana neutrino masses of the standard model neutrinos.

   hep-phJHEP(2023)·18 citations
3. 03*

   Neutrino deep-inelastic scattering cross sections from 100 GeV to 1000 EeV

   Daniel R. Stump🇺🇸

   The CTEQ-TEA Collaboration has calculated neutrino-nucleon cross sections, based on CTEQ18 NNLO parton distribution functions.

   hep-ph0 citations
4. 04*

   The semi-inclusive deeply inelastic scattering in the eN collinear frame

   W. Yang🇨🇳

   The deeply inelastic scattering is one of the most important processes in studying the nucleon structure. Theoretical calculations for both the inclusive one and the semi-inclusive one are generally carried out in the virtual photon-nucleon collinear frame in which virtual photon does not have the transverse components. Expressions in this frame are written in relatively simple forms. Nevertheless, it is also meaningful to calculate the scattering process in the electron-nucleon collinear frame where new measurement schemes are obtained. In the present paper, we reconsider the semi-inclusive deeply inelastic scattering process in the electron-nucleon collinear frame and present the results of azimuthal asymmetries and quark intrinsic asymmetries. We find that the differential cross sections in these two frames are the same at leading twist level but different at higher twist level. Azimuthal asymmetries and intrinsic asymmetries in these two frames have the same forms but different kinematic factors. For the sake of completeness, both the electromagnetic and weak interactions are considered in our calculations. The neutral current measurements in the scattering process could be used as electroweak precision tests which can provide new accurate determinations of the electroweak couplings.

   hep-phPRD(2023)·8 citations
5. 05*

   The $b$ quark fragmentation fractions at LHCb and meson decays with heavy quark spectators

   C. O. Dib🇨🇱 · C. S. Kim🇰🇷 · N. A. Neill🇨🇱

   We study the current estimates of $B_c\to B_s\pi$ to extract the fragmentation fraction $f_c/f_s$ at the LHCb. A rather robust estimate of $Br(B_c\to B_s\pi )$ based on factorization and lattice results for the form factor gives $f_c/f_s\sim 0.056$ with a $16\%$ error. We also revisit the extraction of $f_s/f_d$ using $B\to D\pi$ instead of the theoretical cleaner but more suppressed channel $B\to DK$. We also find a tension on the predictions of $Br(B_c\to J/\psi \pi )$ and $Br(B_c\to B_s\pi )$ considering the measurements of these modes at LHCb, and find that, within a $23\%$ uncertainty, only the lower end of the current prediction range $Br(B_c\to J/\psi )\sim 0.4\%-1.7\%$ would be consistent with the LHCb measurements.

   hep-phEPJC(2023)·4 citations
6. 06*

   The twist-3 gluon contribution to Sivers asymmetry in $J/\psi$ production in semi-inclusive deep inelastic scattering

   Longjie Chen🇨🇳 · Hongxi Xing🇨🇳 · Shinsuke Yoshida🇨🇳

   We carry out the first calculation for the twist-3 gluon contribution to the single transverse-spin asymmetry(SSA) in $J/\psi$ production in semi-inclusive deep inelastic scattering. Our result shows that the $J/\psi$ SSA is an ideal observable to pin down the $C$-even type twist-3 gluon distribution that has a direct relationship with the gluon transverse-momentum-dependent distribution function. We also perform some numerical simulations of the $J/\psi$ SSA for the kinematics accessible at the future electron-ion-collider experiment. For color-singlet contribution, the hadronization effect of $J/\psi$ is completely canceled at the level of the SSA and the spin-dependent structure functions directly reflect the behavior of the $C$-even twist-3 gluon distribution.

   hep-phPRD(2023)·8 citations
7. 07*

   Exclusive $J/\Psi$ plus jet associated production in ultraperipheral $PbPb$ collisions

   Victor P. Goncalves🇧🇷 · Michael Klasen🇩🇪 · Bruno D. Moreira🇧🇷

   The study of exclusive processes in ultraperipheral collisions at the Large Hadron Collider (LHC) has allowed us to test several aspects of the Standard Model and to search for New Physics. In this letter, we investigate the possibility of using these processes to improve our understanding of the quarkonium production mechanism through the study of the exclusive $J/\Psi$ plus jet associate production in ultraperipheral $PbPb$ collisions. We estimate the transverse - momentum and rapidity distributions considering that the $\gamma \gamma \to J/\Psi +X$ ($X=\gamma ,g$) subprocess is described by the Non - Relativistic QCD (NRQCD) formalism and present predictions for the rapidity ranges covered by central and forward detectors. The experimental separation of these events is discussed and the results indicate that a future experimental analysis is, in principle, feasible in future runs of the LHC and the Future Circular Collider (FCC).

   hep-phnucl-thEPJC(2023)·3 citations
8. 08*

   Quark flavour physics: status and future prospects

   Vladimir V. Gligorov🇫🇷

   Quark flavour physics is the study of hadrons, their properties, and their decays into other particles. As a discipline it simultaneously catalogues the nature of physical states within the Standard Model of particle physics, and in doing so tests the consistency and completeness of the Standard Model's description of reality. Following the discovery of the Higgs field, it is more essential than ever to critically examine the Standard Model's own coherence. Precision studies of quark flavour are one of the most sensitive experimental instruments for this task. I give a brief and necessarily selective overview of recent developments in quark flavour physics and discuss prospects for the next generation of experiments and facilities, with an emphasis on the energy scales of beyond Standard Model physics probed by these types of measurements.

   hep-phhep-exInt.J.Mod.Phys.A(2023)·4 citations
9. 09*

   Production of fully-heavy tetraquark states through the double parton scattering mechanism in $pp$ and $pA$ collisions

   L. M. Abreu🇧🇷 · F. Carvalho🇧🇷 · J. V. C. Cerqueira · V. P. Goncalves🇧🇷

   The production of fully-heavy tetraquark states in proton-proton ($pp$) and proton-nucleus ($pA$) collisions at the center-of-mass energies of the Large Hadron Collider (LHC) and at the Future Circular Collider (FCC) is investigated considering that these states are produced through the double parton scattering mechanism. We estimate the cross sections for the $T_{4c}$, $T_{4b}$ and $T_{2b2c}$ states and present predictions for $pp$, $pCa$ and $pPb$ collisions considering the rapidity ranges covered by central and forward detectors. We demonstrate that the cross sections for $pA$ collisions are enhanced in comparison to the $pp$ predictions scaled by the atomic number. Moreover, our results indicate that a search of these exotic states is, in principle, feasible in the future runs of the LHC and FCC.

   hep-phnucl-thEPJC(2024)·17 citations
10. 10*

    On the possibility of observing tetraquarks in the K+ beam

    A.S. Gerasimov🇷🇺 · A.K. Likhoded🇷🇺 · V.A. Petrov🇷🇺 · V.D. Samoylenko🇷🇺

    Various models of tetraquark generation in the reaction $K^{+}p\to T(us;\bar{s}\bar{s})X$ are considered. The predictions for corresponding inclusive spectra were evaluated at the energy 32 and 250 GeV.

    hep-phhep-exMoscow Univ.Phys.Bull.(2023)·2 citations
11. 11*

    Searching for supermassive charged gravitinos in underground experiments

    Krzysztof A. Meissner🇵🇱 · Hermann Nicolai🇩🇪

    We examine possible experimental signatures that may be exploited to search for stable supermassive particles with electric charges of $O(1)$ in future underground experiments, and the upcoming JUNO experiment in particular. The telltale signal providing a unique signature of such particles, would be a correlated sequence of three or more nuclear recoils along a straight line, corresponding to the motion of a non-relativistic ($\beta \lesssim 10^{-2}$) particle that could enter the detector from any direction. We provide some preliminary estimates for the expected event rates.

    hep-phhep-thEPJC(2024)·1 citation
12. 12*

    Exploring kaon induced reactions for unraveling the nature of the scalar meson $a_0(1817)$

    Xiao-Yun Wang🇨🇳 · Hui-Fang Zhou🇨🇳 · Xiang Liu🇨🇳

    In this study, we comprehensively investigate the production of isovector scalar meson $a_0(1817)$ using the effective Lagrangian approach. Specifically, we employ the Reggeized $t$ channel Born term to calculate the total and differential cross sections for the reaction $K^{-}p\to a_0(1817)\Lambda$. Our analysis reveals that the optimal energy range for detecting the $a_0(1817)$ meson lies between $W=3.4$ GeV and $W=3.6$ GeV, where the predicted total cross section reaches a minimum value of 112 nb. Notably, the $t$ channel, as predicted by the Regge model, significantly enhances the differential cross sections, particularly at extreme forward angles. Furthermore, we investigate the Dalitz processes of $2\to 3$ and discuss the feasibility of detecting the $a_0(1817)$ meson in experiments such as J-PARC.

    hep-phPRD(2023)·15 citations
13. 13*

    Collective modes of a collisional anisotropic quark-gluon plasma

    Ruizhe Zhao🇨🇳 · Luhua Qiu🇨🇳 · Yun Guo🇨🇳 · Michael Strickland🇺🇸

    In this paper we consider the collective modes of a momentum-space anisotropic quark-gluon plasma taking into account the effect of collisions between the plasma constituents. Our analysis is carried out using a collisional kernel of Bhatnagar-Gross-Krook form and extends prior analyses in the literature by considering all possible angles of propagation of the gluonic modes relative to the momentum-anisotropy axis. We extract both the stable and unstable modes as a function of the collision rate and confirm prior findings that gluonic unstable modes can be eliminated from the spectrum if the collision rate is sufficiently large. In addition, we discuss the conditions necessary for the existence of unstable modes and present evidence that unstable mode growth rates are maximal for modes with momentum along the anisotropy direction. Finally, we demonstrate that when there is a finite collisional rate, gluonic unstable modes are absent from the spectrum at both small and large momentum anisotropy. These results pave the way for understanding the impact of collisions on a variety of non-equilibrium quark-gluon plasma observables.

    hep-phPRD(2023)·8 citations
14. 14*

    Holographic description of elastic photon-proton and photon-photon scattering

    Akira Watanabe🇨🇳 · Zabihullah Ahmadi🇨🇳 · Zhibo Liu🇨🇳 · Wei Xie🇨🇳

    We investigate the elastic photon-proton and photon-photon scattering in a holographic QCD model, focusing on the Regge regime. Considering contributions of the Pomeron and Reggeon exchange, the total and differential cross sections are calculated. While our model involves several parameters, by virtue of the universality of the Pomeron and Reggeon, for most of them the values determined in the preceding study on the proton-proton and proton-antiproton scattering can be employed. Once the two adjustable parameters, the Pomeron-photon and Reggeon-photon coupling constant, are determined with the experimental data of the total cross sections, predicting the both cross sections in a wide kinematic region, from the GeV to TeV scale, becomes possible. We show that the total cross section data can be well described within the model, and our predictions for the photon-proton differential cross section are consistent with the data.

    hep-phhep-exnucl-exnucl-thPLB(2024)·2 citations
15. 15*

    Reviving sub-TeV $SU(2{)}_L$ lepton doublet Dark Matter

    Purusottam Ghosh🇮🇳 · Sk Jeesun🇮🇳

    In this work we study the hybrid kind of dark matter(DM) production mechanism where both thermal and non-thermal contribution at two different epochs set the DM relic abundance. This hybrid set up in turn shifts the parameter space of DM in contrast to pure thermal DM scenario. We review such production mechanism in the context of the $SU(2{)}_L$ lepton doublet dark matter ($\Psi$) augmented with an additional singlet dark scalar ($S$). The neutral component of the dark doublet can serve as a stable DM candidate and in pure thermal scenario, it is under-abundant as well as excluded from direct detection constraints due to its strong gauge interactions in the sub-TeV mass regime. However, in addition to the thermal contribution, the late time non-thermal DM production from the decay of the long-lived dark scalar $S$ helps to fulfill the deficit in DM abundance. On the other hand, the strong gauge mediated direct detection constraint can be evaded with the help of a $SU(2{)}_L$ triplet scalar(with $Y=2$), resulting a pseudo-Dirac DM. To realize our proposed scenario we impose a discrete ${\mathcal{Z}}_2$ symmetry under which both $\Psi$ and $S$ are odd while rest of the fields are even. We find the lepton doublet pseudo-Dirac DM with mass $\sim 450-1200$ GeV, compatible with the observed relic density, direct, indirect, and existing collider search constraints.

    hep-phEPJC(2023)·7 citations
16. 16*

    Disentangle Neutrino Electromagnetic Properties with Atomic Radiative Pair Emission

    Shao-Feng Ge🇨🇳 · Pedro Pasquini🇨🇳

    We elaborate the possibility of using the atomic radiative emission of neutrino pair (RENP) to probe the neutrino electromagnetic properties, including magnetic and electric dipole moments, charge radius, and anapole. With the typical O(eV) momentum transfer, the atomic RENP is sensitive to not just the tiny neutrino masses but also very light mediators to which the massless photon belongs. The neutrino EM properties introduce extra contribution besides the SM one induced by the heavy W/Z gauge bosons. Since the associated photon spectrum is divided into several sections whose boundaries are determined by the final-state neutrino masses, it is possible to identify the individual neutrino EM form factor elements. Most importantly, scanning the photon spectrum inside the particular section with deviation from the SM prediction once observed allows identification of the neutrino EM form factor type. The RENP provides an ultimate way of disentangling the neutrino EM properties to go beyond the current experimental searches or observations.

    hep-phhep-exJHEP(2023)·6 citations
17. 17*

    Quantum decay of scalar and vector boson stars and oscillons into gravitons

    Kazunori Nakayama🇯🇵 · Fuminobu Takahashi🇯🇵 · Masaki Yamada🇯🇵

    We point out that a soliton such as an oscillon or boson star inevitably decays into gravitons through gravitational interactions. These decay processes exist even if there are no apparent self-interactions of the constituent field, scalar or vector, since they are induced by gravitational interactions. Hence, our results provide a strict upper limit on the lifetime of oscillons and boson stars including the dilute axion star. We also calculate the spectrum of the graviton background from decay of solitons.

    hep-phastro-ph.COhep-thJCAP(2023)·4 citations
18. 18*

    Inclusive probability to record an electron in elastic electromagnetic scattering by a spin one-half hadron wave packet

    P.O. Kazinski🇷🇺 · D.I. Rubtsova🇷🇺 · A.A. Sokolov🇷🇺

    The inclusive probability to record an electron in elastic electromagnetic scattering of an electron by a spin one-half hadron is obtained, the initial quantum states of the electron and the hadron being described by the density matrices of a general form. Contrary to the Rosenbluth formula for the differential cross-section for this process, the first nontrivial contribution to the inclusive probability turns out to be of order $\alpha$ and not ${\alpha }^2$. This contribution describes the interference between the trivial contribution to the $S$-matrix and the leading contribution to its connected part. The explicit expression for this interference terms is derived. For example, for Gaussian wave packets the interference contribution to the inclusive probability is of relative order $2\times 10^{-2}$ in comparison with the contribution of the free passed particle for the nonrelativistic proton and the $10$ MeV electron with the normal deviation of momenta in the electron and hadron wave packets of order $10$ keV. It is shown that the same interference term arises when the electron is scattered by the classical electromagnetic field produced by the hadron electromagnetic current averaged with respect to the free evolving density matrix of the hadron, even in the case of a single hadron. The interference term describes coherent scattering of the electron by the hadron wave packet and is immune to the quantum recoil experienced by a hadron due to scattering. The effective electron mass operator is found on the mass-shell.

    hep-phPRD(2023)·4 citations
19. 19*

    Transversity distributions and tensor charges of the nucleon: extraction from dihadron production and their universal nature

    C. Cocuzza🇺🇸 · A. Metz🇺🇸 · D. Pitonyak🇺🇸 · A. Prokudin🇺🇸 · N. Sato🇺🇸 · R. Seidl🇺🇸

    We perform the first global quantum chromodynamics (QCD) analysis of dihadron production for a comprehensive set of data in electron-positron annihilation, semi-inclusive deep-inelastic scattering, and proton-proton collisions, from which we extract simultaneously the transversity distributions of the nucleon and ${\pi }^{+}{\pi }^{-}$ dihadron fragmentation functions. We incorporate in our fits known theoretical constraints on transversity, namely, its small-$x$ asymptotic behavior and the Soffer bound. We furthermore show that lattice-QCD results for the tensor charges can be successfully included in the analysis. This resolves the previously reported incompatibility between the tensor charges extracted from dihadron production data and lattice QCD. We also find agreement with results for the transversity and tensor charges obtained from measurements on single-hadron production. Overall, our work demonstrates for the first time the universal nature of all available information for the transversity distributions and the tensor charges of the nucleon.

    hep-phhep-exhep-latPRL(2024)·56 citations
20. 20*

    Collider Signatures of Near-Continuum Dark Matter

    Steven Ferrante🇺🇸 · Seung J. Lee🇰🇷 · Maxim Perelstein🇺🇸

    In this paper we study a near-continuum dark matter model, in which dark sector consists of a tower of closely spaced states with weak-scale masses. We construct a five-dimensional model which naturally realizes this spectrum. The dark matter is described by a bulk field, which interacts with the brane-localized Standard Model sector via a Z portal. We then study collider signatures of this model. Near-continuum dark matter states produced in a collider undergo cascade decays, resulting in events with high multiplicity of jets and leptons, large missing energy, and displaced vertices. A custom-built Monte Carlo tool described in this paper allows for detailed simulation of the signal events. We present results of such simulations for the case of electron-positron collisions.

    hep-phJHEP(2024)·8 citations
21. 21*

    Impact of recent MINERvA measurement of the antineutrino-proton scattering cross-section on the generalized parton distributions

    Fatemeh Irani🇮🇷 · Muhammad Goharipour🇮🇷 · Hadi Hashamipour🇮🇷 · K. Azizi🇮🇷

    We investigate the impact of the new measurement of the antineutrino-proton scattering cross-section from the MINERvA Collaboration on generalized parton distributions (GPDs), particularly the polarized GPDs denoted as ${\tilde{H}}^q$. To achieve this, we perform some QCD analyses of the MINERvA data, in addition to all available data of the proton's axial form factors. We demonstrate that MINERvA data lead to consistent results with other related experimental data, confirming the universality of GPDs. Our results indicate that MINERvA data can impose new constraints on GPDs, particularly on ${\tilde{H}}^q$. Our predictions for the proton's axial charge radius, WACS cross-section, and axial form factor show good consistency with those of other studies and measurements. This leads us to conclude that the result of a more comprehensive analysis, considering all related experimental data, is not only reasonable but also more reliable, even in light of existing tensions among the data. The present study can be considered as a guideline for performing a new and comprehensive QCD global analysis of GPDs including the MINERvA measurements like that presented in Phys. Rev. D \textbf{107}, 096005 (2023).

    hep-phhep-exhep-latPRD(2023)·19 citations
22. 22*

    Freeze-in at stronger coupling

    Catarina Cosme🇵🇹 · Francesco Costa🇩🇪 · Oleg Lebedev🇫🇮

    Predictivity of many non-thermal dark matter (DM) models is marred by the gravitational production background. This problem is ameliorated in models with lower reheating temperature $T_R$, which allows for dilution of gravitationally produced relics. We study the freeze-in dark matter production mechanism in the thermal bath with the electroweak scale temperature. The process is Boltzmann-suppressed if the dark matter mass is above $T_R$. In this case, the coupling to the thermal bath has to be significant to account for the observed dark matter relic density. As a result, the direct DM detection experiments already probe such freeze-in models, excluding significant parts of parameter space. The forthcoming experiments will explore this framework further, extending to lower couplings and higher reheating temperatures.

    hep-phastro-ph.COPRD(2024)·68 citations
23. 23*

    Vector-like symmetries and parity conservation in gauge theories with Yukawa couplings

    Alessandro Valenti🇮🇹 · Luca Vecchi🇮🇹

    Non-perturbative results in QCD-like theories can be derived employing positivity of the Euclidean path integral measure, as pioneered by Weingarten, Vafa, Witten. We show that positivity of the measure can be generalized to parity-invariant theories with Yukawa couplings to fundamental scalars, provided the fermions are Dirac and carry a real representation of the gauge group. This result allows us to demonstrate the conservation of parity and vector-like flavor symmetries in such theories, as well as to derive exact inequalities among hadrons' masses.

    hep-phhep-lathep-thJHEP(2024)·3 citations
24. 24*

    Real Time Quarkonium Transport Coefficients in Open Quantum Systems from Euclidean QCD

    Bruno Scheihing-Hitschfeld🇺🇸 · Xiaojun Yao🇺🇸

    Recent open quantum system studies showed that quarkonium time evolution inside the quark-gluon plasma is determined by transport coefficients that are defined in terms of a gauge invariant correlator of two chromoelectric field operators connected by an adjoint Wilson line. We study the Euclidean version of the correlator for quarkonium evolution and discuss the extraction of the transport coefficients from this Euclidean correlator, highlighting its difference from other problems that also require reconstructing a spectral function, such as the calculation of the heavy quark diffusion coefficient. Along the way, we explain why the transport coefficient ${\gamma }_{\mathrm{adj}}$ differs from ${\gamma }_{\mathrm{fund}}$ at finite temperature at $\mathcal{O}(g^4)$, in spite of the fact that their corresponding spectral functions differ only by a temperature-independent term at the same order. We then discuss how to evaluate the Euclidean correlator via lattice QCD methods, with a focus on reducing the uncertainty caused by infrared renormalons in determining the renormalization factor nonperturbatively.

    hep-phhep-latnucl-thPRD(2023)·43 citations
25. 25*

    CMB Spectral Distortions from an Axion-Dark Photon-Photon Interaction

    Anson Hook🇺🇸 · Gustavo Marques-Tavares🇺🇸 · Clayton Ristow🇺🇸

    The presence of a plethora of light spin 0 and spin 1 fields is motivated in a number of BSM scenarios, such as the axiverse. The study of the interactions of such light bosonic fields with the Standard Model has focused mostly on interactions involving only one such field, such as the axion ($\varphi$) coupling to photons, $\varphi F\tilde{F}$, or the kinetic mixing between photon and the dark photon, $F{F}_D$. In this work, we continue the exploration of interactions involving two light BSM fields and the standard model, focusing on the mixed axion-photon-dark-photon interaction $\varphi F{\tilde{F}}_D$. If either the axion or dark photon are dark matter, we show that this interaction leads to conversion of the CMB photons into a dark sector particle, leading to a distortion in the CMB spectrum. We present the details of these unique distortion signatures and the resulting constraints on the $\varphi F{\tilde{F}}_D$ coupling. In particular, we find that for a wide range of masses, the constraints from these effect are stronger than on the more widely studied axion-photon coupling.

    hep-phastro-ph.COJHEP(2024)·18 citations
26. 26*

    Nonlinear photon-plasma interaction and the black hole superradiant instability

    Enrico Cannizzaro🇮🇹 · Fabrizio Corelli🇮🇹 · Paolo Pani🇮🇹

    Electromagnetic field confinement due to plasma near accreting black holes can trigger superradiant instabilities at the linear level, limiting the spin of black holes and providing novel astrophysical sources of electromagnetic bursts. However, nonlinear effects might jeopardize the efficiency of the confinement, rending superradiance ineffective. Motivated by understanding nonlinear interactions in this scenario, here we study the full $3+1$ nonlinear dynamics of Maxwell equations in the presence of plasma by focusing on regimes that are seldom explored in standard plasma-physics applications, namely a generic electromagnetic wave of very large amplitude but small frequency propagating in an inhomogeneous, overdense plasma. We show that the plasma transparency effect predicted in certain specific scenarios is not the only possible outcome in the nonlinear regime: plasma blow-out due to nonlinear momentum transfer is generically present and allows for significant energy leakage of electromagnetic fields above a certain threshold. We argue that such effect is sufficient to dramatically quench the plasma-driven superradiant instability around black holes even in the most optimistic scenarios.

    ↳ gr-qcastro-ph.HEhep-phphysics.plasm-phPRD(2024)·23 citations
27. 27*

    Efficient solver of relativistic hydrodynamics with implicit Runge-Kutta method

    Nathan Touroux🇯🇵 · Masakiyo Kitazawa🇯🇵 · Koichi Murase🇯🇵 · Marlene Nahrgang🇫🇷

    We propose a new method to solve the relativistic hydrodynamic equations based on implicit Runge-Kutta methods with a locally optimized fixed-point iterative solver. For numerical demonstration, we implement our idea for ideal hydrodynamics using the one-stage Gauss-Legendre method as an implicit method. The accuracy and computational cost of our new method are compared with those of explicit ones for the (1+1)-dimensional Riemann problem, as well as the (2+1)-dimensional Gubser flow and event-by-event initial conditions for heavy-ion collisions generated by TrENTo. We demonstrate that the solver converges with only one iteration in most cases, and as a result, the implicit method requires a smaller computational cost than the explicit one at the same accuracy in these cases, while it may not converge with an unrealistically large $\Delta t$. By showing a relationship between the one-stage Gauss-Legendre method with the iterative solver and the two-step Adams-Bashforth method, we argue that our method benefits from both the stability of the former and the efficiency of the latter.

    ↳ nucl-thhep-phphysics.comp-phphysics.flu-dynPTEP(2024)·1 citation
28. 28*

    Decays of $1^{-+}$ Charmoniumlike Hybrid

    Chunjiang Shi🇨🇳 · Ying Chen🇨🇳 · Ming Gong🇨🇳 · Xiangyu Jiang🇨🇳 · Zhaofeng Liu🇨🇳 · Wei Sun🇨🇳

    By extracting the transition amplitudes, we give the first lattice QCD prediction of the two-body decay partial widths of the $1^{-+}$ charmoniumlike hybrid ${\eta }_{c1}$. Given the calculated mass value $m_{{\eta }_{c1}}=4.329(36)$ GeV, the ${\eta }_{c1}$ decay is dominated by the open charm modes $D_1\bar{D}$, $D^{\ast }\bar{D}$ and $D^{\ast }{\bar{D}}^{\ast }$ with partial widths of $258(133)$ MeV, $88(18)$ MeV and $150(118)$ MeV, respectively. The coupling of ${\eta }_{c1}$ to ${\chi }_{c1}$ plus a flavor singlet pseudoscalar is not small, but ${\chi }_{c1}\eta$ decay is suppressed by the small $\eta -{\eta }^{\prime }$ mixing angle. The partial width of ${\eta }_{c1}\to {\eta }_c{\eta }^{\prime }$ is estimated to be around 1 MeV. We suggest experiments to search for ${\eta }_{c1}$ in the $P$-wave $D^{\ast }\bar{D}$ and $D^{\ast }{\bar{D}}^{\ast }$ systems. Especially, the polarization of $D^{\ast }{\bar{D}}^{\ast }$ can be used to distinguish the $1^{-+}$ product (total spin $S=1$) from $1^{--}$ products ($S=0$).

    ↳ hep-lathep-exhep-phPRD(2024)·14 citations
29. 29*

    Future accelerator projects: new physics at the energy frontier

    Anadi Canepa🇺🇸 · Monica D'Onofrio ((1) Fermilab, (2) Liverpool)🇬🇧

    High-energy colliders provide direct access to the energy frontier, allowing to search for new physics at scales as high as the machine's center-of-mass energy, perform precision measurements of the Standard Model (SM) parameters, including those related to the flavor sector, and determine the Higgs boson properties and their connection to electroweak symmetry breaking. Each proposed future collider option has its own specific science goals and capabilities, depending on the designed running energy (energies) amongst other parameters. In this paper, an overview of the discovery potential of future circular and linear colliders is presented. Results from searches for beyond the Standard Model (BSM) phenomena at proton-proton, proton-electron, electron-positron, and muon-antimuon colliders are summarized.

    ↳ physics.acc-phhep-phFront.in Phys.(2022)·13 citations
30. 30*

    Dilatons Improve (Non)-Goldstones

    Roman Zwicky🇬🇧

    Shift symmetry forbids conformal coupling of Goldstone bosons from internal symmetries, but not for spontaneously broken conformal symmetry. Its Goldstone boson, the dilaton $D$, admits and indeed requires, an improvement term ${\mathcal{L}}_R\propto R{e}^{-2D/F_D}$ as it realises the Goldstone matrix element in the effective theory. The improvement, combined with Weyl-gauging, enables conformal coupling to Goldstone bosons and other particles of arbitrary Weyl-weight. While improvement does not affect scattering amplitudes in flat space, it impacts gravitational form factors decisively, giving rise to the dilaton pole in the spin-zero channel. We compute leading-order scalar, fermion, pion, and dilaton form factors, confirming low-energy constraints. The dilaton decoupling limit further implies that the operator driving spontaneous chiral symmetry breaking has scaling dimension $\Delta =d-2$.

    ↳ hep-thgr-qchep-lathep-phNPB(2026)·25 citations
31. 31*

    Radiation Emission during the Erasure of Magnetic Monopoles

    Maximilian Bachmaier🇩🇪 · Gia Dvali🇩🇪 · Juan Sebastián Valbuena-Bermúdez🇩🇪

    We study the interactions between 't Hooft-Polyakov magnetic monopoles and the domain walls formed by the same order parameter within an $SU(2)$ gauge theory. We observe that the collision leads to the erasure of the magnetic monopoles, as suggested by Dvali, Liu, and Vachaspati. The domain wall represents a layer of vacuum with un-Higgsed $SU(2)$ gauge symmetry. When the monopole enters the wall, it unwinds, and the magnetic charge spreads over the wall. We perform numerical simulations of the collision process and in particular analyze the angular distribution of the emitted electromagnetic radiation. As in the previous studies, we observe that erasure always occurs. Although not forbidden by any conservation laws, the monopole never passes through the wall. This is explained by entropy suppression. The erasure phenomenon has important implications for cosmology, as it sheds a very different light on the monopole abundance in post-inflationary phase transitions and provides potentially observable imprints in the form of electromagnetic and gravitational radiation. The phenomenon also sheds light on fundamental aspects of gauge theories with coexisting phases, such as confining and Higgs phases. Additionally to the figures, the results of the numerical simulations can be found in the following video: https://youtu.be/JZaXUYikQbo

    ↳ hep-thgr-qchep-lathep-phPRD(2023)·23 citations
32. 32*

    Mass spectra in $\mathcal{N}=1SU(N_c)$ SQCD with $N_F=N_c$ and problems with S-confinement

    Victor L. Chernyak🇷🇺

    The low energy mass spectra of the direct $SU(N_c)$, $N_F=N_c$ $\mathcal{N}=1$ SQCD theory and its N.Seiberg's dual variant [1], are calculated in sections 2 and 3. It is shown that these two mass spectra are parametrically different, both for equal or unequal small quark masses $m_{Q,i}\ne 0$. In [17] the very special non-SUSY lattice $SU(N_c)$ QCD theory with $N_F=N_c$ scalar defective "quarks" was considered by E.Fradkin and S.H.Shenker. The conclusion of [17] was that the transition between the confinement and higgs regimes in this theory is the analytic crossover, not the non-analytic phase transition. And although the theory considered in [17] was very specific, the experience shows that up to now there is a widely spread opinion that this conclusion has general applicability. This model used in [17] is criticized in section 5 of this paper as incompatible with and qualitatively different from the standard non-SUSY $SU(N_c)$ $N_F=N_c$ QCD theory with standard scalar quarks ${\varphi }_{\beta }^i$ with all their $2N_F^2$ real degrees of freedom. It is emphasized that this model [17] is really the Stuckelberg $SU(N_c)$ YM-theory with no dynamical electric quarks and with massive all $N_c^2-1$ electric gluons with fixed by hands nonzero masses. There is no genuine confinement in this theory, it stays permanently in the completely higgsed phase only. And this is a reason for a crossover in this theory. While in the theory with standard scalar quarks there is the phase transition between the confinement and higgs phases. Besides, in section 5, the arguments presented in [2] by K.Intriligator and N.Seiberg for the standard direct $SU(N_c)$, $N_F=N_c$ $\mathcal{N}=1$ SQCD in support of the crossover from [17] are criticized as erroneous. Besides, in section 5 a qualitative mechanism of confinement in our ordinary (i.e. not SUSY) QCD is proposed.

    ↳ hep-thhep-lathep-ph1 citation
33. 33*

    Macroscopic Dark Matter Detection with Gravitational Wave Experiments

    Yufeng Du🇺🇸 · Vincent S. H. Lee🇺🇸 · Yikun Wang🇺🇸 · Kathryn M. Zurek🇺🇸

    We study signatures of macroscopic dark matter (DM) in current and future gravitational wave (GW) experiments. Transiting DM with a mass of $\sim 10^5-10^{15}$ kg that saturates the local DM density can be potentially detectable by GW detectors, depending on the baseline of the detector and the strength of the force mediating the interaction. In the context of laser interferometers, we derive the gauge invariant observable due to a transiting DM, including the Shapiro effect (gravitational time delay accumulated during the photon propagation), and adequately account for the finite photon travel time within an interferometer arm. In particular, we find that the Shapiro effect can be dominant for short-baseline interferometers such as Holometer and GQuEST. We also find that proposed experiments such as Cosmic Explorer and Einstein Telescope can constrain a fifth force between DM and baryons, at the level of strength $\sim 10^3$ times stronger than gravity for, e.g., kg mass DM with a fifth-force range of $10^6$ m.

    ↳ astro-ph.COgr-qchep-phPRD(2023)·13 citations
34. 34*

    Savior Curvatons and Large non-Gaussianity

    Jackie Lodman🇺🇸 · Qianshu Lu🇺🇸 · Lisa Randall🇺🇸

    Curvatons are light (compared to the Hubble scale during inflation) spectator fields during inflation that potentially contribute to adiabatic curvature perturbations post-inflation. They can alter CMB observables such as the spectral index $n_s$, the tensor-to-scalar ratio $r$, and the local non-Gaussianity $f_{\mathrm{NL}}^{(\mathrm{loc})}$. We systematically explore the observable space of a curvaton with a quadratic potential. We find that when the underlying inflation model does not satisfy the $n_s$ and $r$ observational constraints but can be made viable with a significant contribution from what we call a savior curvaton, a large $f_{\mathrm{NL}}^{(\mathrm{loc})}$ is inevitable. On the other hand, when the underlying inflation model already satisfies the $n_s$ and $r$ observational constraints, so significant curvaton contribution is forbidden, a large $f_{\mathrm{NL}}^{(\mathrm{loc})}$ is possible in the exceptional case when the isocurvature fluctuation in the curvaton fluid is much greater than the global curvature fluctuation.

    ↳ astro-ph.COhep-phJHEP(2023)·6 citations
35. 35*

    Coupling Metric-Affine Gravity to the Standard Model and Dark Matter Fermions

    Claire Rigouzzo🇬🇧 · Sebastian Zell🇧🇪

    General Relativity (GR) exists in different formulations, which are equivalent in pure gravity. Once matter is included, however, observable predictions generically depend on the version of GR. In order to quantify the resulting ambiguity, we employ metric-affine gravity, which encompasses as special cases the metric, Palatini, Einstein-Cartan and Weyl formulations. We first discuss the interaction of fermions with torsion and non-metricity, also commenting on projective symmetry. With a view towards the Standard Model, we then construct a generic model of (complex) scalar, fermionic and gauge fields coupled to GR and derive an equivalent metric theory, which features numerous new interaction terms. As a first observable consequence, we point out that a gravitational mechanism for producing dark matter in the form of singlet fermions can be used to distinguish between metric gravity and other formulations of GR.

    ↳ gr-qchep-phhep-thPRD(2023)·44 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.