Tue·Apr 12, 2022Tuesday·April 12, 2022

1. 01*

   The ultra-high-energy neutrino-nucleon cross section: measurement forecasts for an era of cosmic EeV-neutrino discovery

   Victor Branco Valera🇩🇰 · Mauricio Bustamante🇩🇰 · Christian Glaser🇸🇪

   Neutrino interactions with protons and neutrons probe their deep structure and may reveal new physics. The higher the neutrino energy, the sharper the probe. So far, the neutrino-nucleon ($\nu N$) cross section is known across neutrino energies from a few hundred MeV to a few PeV. Soon, ultra-high-energy (UHE) cosmic neutrinos, with energies above 100 PeV, could take us farther. So far, they have evaded discovery, but upcoming UHE neutrino telescopes endeavor to find them. We present the first detailed measurement forecasts of the UHE $\nu N$ cross section, geared to IceCube-Gen2, one of the leading detectors under planning. We use state-of-the-art ingredients in every stage of our forecasts: in the UHE neutrino flux predictions, the neutrino propagation inside Earth, the emission of neutrino-induced radio signals in the detector, their propagation and detection, and the treatment of backgrounds. After 10 years, if at least a few tens of UHE neutrino-induced events are detected, IceCube-Gen2 could measure the $\nu N$ cross section at center-of-mass energies of $\sqrt{s}\approx 10-100$ TeV for the first time, with a precision comparable to that of its theory prediction.

   hep-phastro-ph.HEhep-exJHEP(2022)·61 citations
2. 02*

   Generation and detection of axions using guided structures

   D. D. Yavuz🇺🇸 · S. Inbar🇺🇸

   We propose a new experimental technique to generate and detect axions in the lab with a good experimental sensitivity over a broad axion mass range. The scheme relies on using laser-based four-wave mixing, which is mediated by the hypothetical axion field. Intense pump and Stokes laser beams that are confined to a waveguide (i.e., for example, an optical fiber) with appropriately chosen frequencies resonantly drive axion generation. Under such a geometry, we predict the existence of guided axion waves, which we refer to as "axitons". These are solutions of the axion Klein-Gordon field equation that are spatially guided by the profiles of the driving pump and Stokes laser beams. These guided axitons can then couple to a nearby fiber and mix with another laser, affecting the propagation of a probe laser beam. A key advantage of the scheme is that the mass range of the hypothetical axion can be scanned by varying the frequencies of the pump and the Stokes laser beams. We predict that, using reasonable parameters, the technique will be able to detect axions in the mass range $10^{-6}$eV $<m<$ $10^{-2}$eV with a sensitivity at the level of $10^{-12}$ GeV${}^{-1}$ for the axion-photon coupling constant.

   hep-phhep-exPRD(2022)·5 citations
3. 03*

   Explaining The Muon $g-2$ Anomaly and New CDF II W-Boson Mass in the Framework of (Extra)Ordinary Gauge Mediation

   Xiao Kang Du🇨🇳 · Zhuang Li🇨🇳 · Fei Wang🇨🇳 · Ying Kai Zhang🇨🇳

   The SUSY contributions $\Delta a_{\mu }$ to muon $g-2$ anomaly can not even reach $3\sigma$ in ordinary gauge mediated SUSY breaking (GMSB) scenarios because of the strong correlations between the colored sparticle masses and the uncolored EW sparticle masses. An interesting extension to GMSB is the (Extra)Ordinary Gauge Mediation (EOGM), which can relax the correlations between squarks and sleptons with non-universal choices for $N_{eff,3}$ and $N_{eff,2}$. We find that EOGM scenarios with $N_{eff,3}\ll N_{eff,2}$ can explain the muon $g-2$ anomaly within $3\sigma$ range, however can not explain the new W-boson mass by CDF II. We also propose to extend EOGM with additional adjoint ${\Sigma }_8$ and ${\Sigma }_3$ messengers at a high scale of order $1.0\times 10^{14}$ GeV, which can shift the gauge coupling unification scale to the string scale. Such EOGM extension scenarios with adjoint messengers could spoil the unwanted gaugino mass ratios and give large SUSY contributions to $\Delta a_{\mu }$ for $N_{eff,3}\ll N_{eff,2}$, which can explain the muon $g-2$ anomaly up to $1\sigma$. Besides, because of the large messenger scale of order $1.0\times 10^{14}$ GeV, such scenarios will in general lead to large $|A_t|$ at the EW scale, which can accommodate the 125 GeV Higgs easily and possibly lead to smaller EWFT as well as BGFT. We discuss the possibility to explain the new CDF II W-boson mass in the GMSB-type framework. We find that SUSY contributions can marginally account for the new W-boson mass in the region with sleptons and wino both being light.

   hep-phNPB(2023)·68 citations
4. 04*

   NMSSM neutralino dark matter for CDF II $W$-boson mass and muon $g-2$ and the promising prospect of direct detection

   Tian-Peng Tang🇨🇳 · Murat Abdughani🇨🇳 · Lei Feng🇨🇳 · Yue-Lin Sming Tsai🇨🇳 · Jian Wu🇨🇳 · Yi-Zhong Fan🇨🇳

   Two experiments from the Fermilab, E989 and CDF II, have reported two anomalies for muon $g-2$ and $W$-boson mass that may indicate the new physics at the low energy scale. Here we examine the possibility of a common origin of these two anomalies in the Next-to-Minimal Supersymmetric Standard Model. Considering various experimental and astrophysical constraints such as the Higgs mass, collider data, flavor physics, dark matter relic density, and direct detection experiments, we find that lighter electroweakinos and sleptons can generate sufficient contributions to muon $g-2$ and $m_W$. Moreover, the corresponding bino-like neutralino dark matter mass is in the $\sim 180-280$ GeV range. Interestingly, the favored DM mass region can soon be entirely probed by ongoing direct detection experiments like PandaX-4T, XENONnT, LUX-ZEPLIN, and DARWIN.

   hep-phastro-ph.COastro-ph.HESCPMA(2023)·79 citations
5. 05*

   Scrutinizing New Physics in Semi-leptonic $B_c\to J/\psi \tau \nu$ Decay

   Ru-Ying Tang🇨🇳 · Zhuo-Ran Huang🇰🇷 · Cai-Dian Lü🇨🇳 · Ruilin Zhu🇨🇳

   We perform a global analysis of the $b\to c\tau \nu$ data using the recent lattice results on the $B_c\to J/\psi$ vector and axial-vector form factors. To explore the effects from the tensor operator of new physics beyond the standard model, we determine the tensor form factors by using the non-relativistic QCD (NRQCD) relations between tensor and (axial-)vector form factors. Based on the lattice+NRQCD form factors, we fit the Wilson coefficients and the new physics couplings in $R_2$, $S_1$ and $U_1$ leptoquark models by including the recently measured $R({\Lambda }_c)$ and imposing the relaxed constraint $\mathcal{B}(B_c\to J/\psi )<30\%$ in light of the recent studies on LEP1 data and $B_c$ lifetime. We give predictions for the experimental observables including $R(J/\psi )$, $P_{\tau }(J/\psi )$, $F_L(J/\psi )$ and ${\mathcal{A}}_{FB}(J/\psi )$ as well as their $q^2$ distribution in new physics scenarios/models. Our results suggest that the longitudinal $\tau$ polarization fraction $P_{\tau }(J/\psi )$ and the forward-backward asymmetry ${\mathcal{A}}_{FB}(J/\psi )$ are useful for testing the $R_2$ leptoquark model.

   hep-phJ.Phys.G(2022)·16 citations
6. 06*

   Collapsing domain walls beyond $Z_2$

   Yongcheng Wu🇺🇸 · Ke-Pan Xie🇺🇸 · Ye-Ling Zhou🇨🇳

   Discrete symmetries are widely imposed in particle theories. It is well-known that the spontaneous breaking of discrete symmetries leads to domain walls. Current studies of domain walls have focused on those from the spontaneous breaking of a $Z_2$ symmetry. Larger discrete symmetries have multiple degenerate vacua, leading to the domain walls in principle different from the simplest $Z_2$ domain wall. We take domain walls from $Z_N$ symmetry breaking as an illustrative study, and study in detail the $Z_3$ case, in which semi-analytical results for the tension and thickness of domain walls are derived. Explicit symmetry breaking terms lead to the dynamics of domain walls collapsing more complicated than the $Z_2$ case. Gravitational wave signals deviate from those from $Z_2$ domain walls.

   hep-phastro-ph.COPRD(2022)·26 citations
7. 07*

   Probing the electroweak symmetry breaking history with Gravitational waves

   Zizhuo Zhao🇨🇳 · Yuefeng Di🇨🇳 · Ligong Bian🇨🇳 · Rong-Gen Cai🇨🇳

   We perform a three dimensional lattice simulation of the electroweak symmetry breaking process through a two-step phase transition, where one of the two steps is a first order phase transition. Our results show that: 1) when the electroweak symmetry breaking is driven by the beyond Standard Model sector around $\sim \mathcal{O}(10^{2-3})$ GeV, the gravitational wave spectra produced from the phase transitions are of broken power-law double-peak shapes; 2) when the electroweak symmetry breaking is induced by a first-order phase transition of a high-scale global U(1) theory, cosmic strings can form and then disappear through particle radiation, and the yielded gravitational wave spectra are of plateau shapes. The two scenarios can be distinguished through probing gravitational wave spectra. Our study suggests that the stochastic gravitational waves provide an alternative way to probe the beyond Standard Model sector relevant to the electroweak symmetry breaking pattern in the early Universe.

   hep-phastro-ph.COJHEP(2023)·16 citations
8. 08*

   Search for lepton-flavor-violating decays of the tau lepton at a future muon collider

   Gholamhossein Haghighat🇮🇷 · Mojtaba Mohammadi Najafabadi🇮🇷

   Tau leptons can have lepton-flavor-violating (LFV) couplings to a muon or an electron and an Axion-Like Particle (ALP). ALPs are pseudo Nambu-Goldstone bosons associated with spontaneously broken global U(1) symmetries. LFV ALPs have been of a great interest in the last several decades as they can address some of the SM long-lasting problems. Assuming a future muon collider proposed by the Muon Accelerator Program (MAP), we search for LFV decays $\tau \to \ell a$ ($\ell =e,\mu$) of one of the tau leptons produced in the muon-anti muon annihilation. The ALP mass is assumed to be in the range 100 eV to 1 MeV and three different chiral structures are considered for the LFV coupling. Using a multivariate technique and performing a parameterized simulation based on the ideal target performance, we obtain expected 95$\%$ confidence level upper limits on the LFV couplings tau-electron-ALP and tau-muon-ALP. Limits are computed assuming the center-of-mass energies of 126, 350 and 1500 GeV which the future muon collider is supposed to operate at. We study the two cases of unpolarized and polarized muon beams and show that taking advantage of tau polarization-induced effects, the main background $\tau \to e/\mu +\nu \bar{\nu }$ can be significantly reduced. Results indicate that current limits on the LFV couplings can be improved by roughly one order of magnitude using the present analysis.

   hep-phSciPost Phys.Proc.(2025)·4 citations
9. 09*

   Exclusive semileptonic $B_c$-meson decays to radially excited charmonium and charm meson states

   Lopamudra Nayak🇮🇳 · P. C. Dash🇮🇳 · Susmita Kar🇮🇳 · N. Barik🇮🇳

   In the wake of recent measurements of ratios of semileptonic branching fractions: ${\mathcal{R}}_{J/\psi },{\mathcal{R}}_D$ and ${\mathcal{R}}_{D^{\ast }}$ reported by the LHCb, BELLE and HFLAV Collaborations, we calculate invariant form factors for the exclusive semileptonic $B_c$-meson decays to radially excited charmonium and charm meson states in the full kinematical region within the framework of relativistic independent quark (RIQ)model. We evaluate the lepton mass effect in the decay processes induced by $b\to c,u$ transition at the quark level. Our predictions on branching fractions for $B_c\to {\eta }_c/\psi (nS)$ are found $\sim 10^{-2}-10^{-4}$ and that for $B_c\to D^{\ast }(nS)$ are $\sim 10^{-4}$ in their $e^{-}$ decay modes, which lie within the detection accuracy of current experiment. Our predictions on branching fractions, forward backward asymmetry and asymmetry parameter are found in reasonable agreement with other model predictions; which can hopefully be tested in future experiments at LHC and Tevatron. Our predicted observable $\mathcal{R}$ in this sector are found comparable to other standard model (SM) predictions that violate the lepton flavor universality hinting at new physics beyond SM.

   hep-phEPJC(2022)·12 citations
10. 10*

    Primary photons, boson star and phase transition

    G.A. Kozlov🇷🇺

    We analyse the possibility that the dark matter candidate is from the approximate scale symmetry theory of the hidden scalar sector. The study includes the warm dark matter scenario and the Bose-Einstein condensation which may lead to the scalar boson stars (BS) giving rise to direct detection through the observation of the primary (direct) photons. The dynamical system of the scalar particles, the dilatons, at finite temperature and chemical potential is considered. The fluctuation of the particle density increases sharply within the increasing of the temperature. When the phase transition approaches, the fluctuation of the particle density has the non-monotonous rising when the ground state of the relative chemical potential tends to the critical value equal to one accompanying by the infinite number of particles. Our results suggest that the phase transition in the BS may be identified through the fluctuation in yield of primary photons induced directly by the conformal anomaly. The fluctuation rate of the photons grows up intensively in the infra-red to become very large at the phase transition.

    hep-phPoS(2022)·0 citations
11. 11*

    The W boson mass weighs in on the non-standard Higgs

    Giacomo Cacciapaglia🇫🇷 · Francesco Sannino🇩🇰

    We consider the implications of the CDF collaboration high-precision measurement of the W boson mass on models with a non-standard Higgs. We show that this requires an enhancement of 3-10% in the non-standard Higgs coupling to the gauge bosons. This is naturally accommodated in dynamical models such as the dilaton Higgs, the Technicolor and glueball Higgs. The needed composite scale between 2 and 3 TeV can also explain the muon g-2 anomaly, as well as possible violations of lepton flavour universality.

    hep-phhep-exhep-latPLB(2022)·68 citations
12. 12*

    Right-handed neutrinos and the CDF II anomaly

    Mattias Blennow🇸🇪 · Pilar Coloma🇪🇸 · Enrique Fernández-Martínez🇪🇸 · Manuel González-López🇪🇸

    We point out that right-handed neutrinos can resolve the tension between the latest CDF II measurement of the $W$-boson mass, $M_W$, and the standard model. Integrating out the new states yields a single $d=6$ operator, which induces a deviation from unitarity in the PMNS matrix. This alters the extraction of the Fermi constant from muon decay and increases the prediction for $M_W$, in line with the CDF II result. Non-unitarity of the PMNS matrix would also affect beta, meson, and tau decays. We find that the CDF II value for $M_W$ can be explained without conflicting with lepton flavour universality constraints or the invisible decay width of the $Z$. However, the so-called Cabibbo angle anomaly is worsened if right-handed neutrinos are the origin of the $d=6$ operator. The situation improves if the operator coefficient is left unconstrained, implying additional sources of new physics, but a common explanation of both anomalies is in tension with universality bounds.

    hep-phPRD(2022)·87 citations
13. 13*

    Production of Higgs boson in association with a pair of fermions in the presence of a circularly polarized laser field

    M. Ouali🇲🇦 · M. Ouhammou🇲🇦 · R. Benbrik🇲🇦 · S. Taj🇲🇦 · B. Manaut🇲🇦

    In the centre of mass frame, we have investigated the process of Higgs production in association with a pair of fermions, $e^{+}{e}^{-}\to f\bar{f}H$, at the leading order inside an intense electromagnetic field with circular polarization. Our analytical calculations are based on the Narrow Width Approximation (NWA), which is valid in the leading order. We have considered only the initial particles inside the laser field as a first step. In the second part, we have embedded both initial and final particles in the laser field. We have analyzed the angular distribution of the produced Higgs boson as a function of the laser parameters in both cases. We have found that in the case where both initial and final particles are embedded in the laser field, the order of magnitude of the differential cross-section of the process $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}H$ is reduced more significantly, while that of the process $e^{+}{e}^{-}\to \nu \bar{\nu }H$ is enhanced.

    hep-phIndian J.Phys.(2024)·3 citations
14. 14*

    Dynamical Minimal Flavour Violating Inverse Seesaw

    Fernando Arias-Aragón🇫🇷 · Enrique Fernández-Martínez🇪🇸 · Manuel González-López🇪🇸 · Luca Merlo🇪🇸

    The Inverse Seesaw mechanism is dynamically realised within the Minimal Lepton Flavour Violation context. Lepton number, whose breaking is spontaneously realised, is generalised to a global Abelian factor of the whole flavour symmetry, that also plays the role of the Peccei-Quinn symmetry. The associated Goldstone boson is a Majoraxion that solves the Strong CP problem and represents a Dark Matter candidate. Three distinct scenarios are identified in terms of flavour symmetry and transformation properties of the exotic neutral leptons that enrich the Standard Model spectrum. The associated phenomenology is studied, focusing on the deviations from unitarity of the PMNS mixing matrix. The strongest constraints arise from the determination of the number of active neutrinos through the invisible width of the $Z$, the comparison of the measured $W$ boson mass with its prediction in terms of the Fermi constant from muon decay, and the null searches for the radiative rare muon decay and $\mu \to e$ conversion in nuclei. The heavy neutral leptons may have masses of a few TeV, leaving open the possibility for a direct detection at future colliders. The impact of the recent measurement of the $W$ mass at the CDF II detector has also been considered, which, in one of the scenarios, points to a sharp prediction for the masses of the heavy neutral leptons at about $2-3$ TeV.

    hep-phJHEP(2022)·61 citations
15. 15*

    Prospects for detecting axion-like particles via the decay $Z\to af\bar{f}$ at future $Z$ factories

    Chong-Xing Yue🇨🇳 · Shuo Yang🇨🇳 · Han Wang🇨🇳 · Nan Zhang🇨🇳

    We investigate the prospects for detecting axion-like particles (ALPs, dubbed as "a") via the decay $Z\to af\bar{f}$ at future $Z$ factories. Considering the decay channels $a\to {\mu }^{+}{\mu }^{-}$ and $a\to b\bar{b}$ , four types of signals ${\mu }^{+}{\mu }^{-}/E$, $bb/E$, $e^{+}{e}^{-}{\mu }^{+}{\mu }^{-}$ and $e^{+}{e}^{-}bb$ are explored. We demonstrate that these channels are promising for detecting ALPs at $Z$ factories and obtain the sensitivity bounds on the couplings $g_{aZZ}$ and $g_{a\gamma Z}$.

    hep-phPRD(2022)·14 citations
16. 16*

    Impact of LHC probes of SUSY and recent measurement of $(g-2{)}_{\mu }$ on ${\mathbb{Z}}_3$-NMSSM

    Junjie Cao🇨🇳 · Fei Li🇨🇳 · Jingwei Lian🇨🇳 · Yusi Pan🇨🇳 · Di Zhang🇨🇳

    It is well known that excessively heavy supersymmetric particles (sparticles) are disfavored to explain the $(g-2{)}_{\mu }$ anomaly, but some people overlook that moderately light sparticles are also disfavored by the LHC probes of supersymmetry. We take the Next-to-Minimal Supersymmetric Standard Model as an example to emphasize the latter point. It is found that, if the theory is required to explain the anomaly at $2\sigma$ level and meanwhile keep consistent with the LHC results, the following lower bounds may be set: $\tan \beta \gtrsim 20$, $|M_1|\gtrsim 275\mathrm{GeV}$, $M_2\gtrsim 300\mathrm{GeV}$, $\mu \gtrsim 460\mathrm{GeV}$, $m_{{\tilde{\mu }}_L}\gtrsim 310\mathrm{GeV}$, and $m_{{\tilde{\mu }}_R}\gtrsim 350\mathrm{GeV}$, where $M_1$ and $M_2$ denote gaugino masses, $\mu$ represents the Higgsino mass, and $m_{{\tilde{\mu }}_L}$ and $m_{{\tilde{\mu }}_R}$ are the mass of Smuons with $L$ and $R$ denoting their dominant chiral component. This observation has significant impacts on dark matter (DM) physics, e.g., the popular $Z$- and Higgs-funnel regions have been excluded, and the Bino-dominated neutralino DM has to co-annihilate with the Wino-dominated electroweakinos (in most cases) and/or Smuons (in few cases) to obtain the correct density. It is also inferred that these conclusions should apply to the Minimal Supersymmetric Standard Model since the underlying physics for the bounds are the same.

    hep-phSCPMA(2022)·29 citations
17. 17*

    Neutron-neutral particle mixing and its observable consequences

    Yongliang Hao🇨🇳 · Dongdong Ni🇨🇳

    In this work, we explore the mixing between neutron ($n$) and elementary neutral particle ($\eta$), which violates both the baryon number ($\mathcal{B}$) and the lepton number ($\mathcal{L}$) by one unit but conserves their difference $(\mathcal{B}-\mathcal{L})$. Such mixing may give rise to non-trivial effects that are different from the Standard Model predictions. We organize our discussions based on two scenarios, roughly depending on whether an interference between oscillation and decay occurs, or whether the new-physics effects associated with the $n$-$\eta$ mixing contribute to the absorptive mixing amplitude. If an oscillation process is not accompanied by an interference between oscillation and decay, or the new-physics interactions do not contribute to the absorptive mixing amplitude, such a process can be classified as pure oscillation. Otherwise, it can be classified as impure oscillation. In the scenario of pure oscillation, CP-violation arising from the Majorana phase can manifest itself through the $n$-$\bar{n}$ oscillation process and may lead to observable effects. In the scenario of impure oscillation, we analyze the testable implications on the masses and lifetimes of the mass eigenstates formed as a result of the $n$-$\bar{n}$ oscillation mediated by $\eta$. In this scenario, we also suggest a unified interpretation of the neutron lifetime anomaly and the $n$-$\bar{n}$ oscillation measurements based on the $n$-$\eta$ mixing. In both scenarios, we present the lower bounds imposed by the experimental searches for $n$-$\bar{n}$ oscillations on the masses of the color multiplet bosons and point out that they could be within the reach of a direct detection at the LHC or future high-energy experiments.

    hep-phnucl-thPRD(2022)·6 citations
18. 18*

    Pseudo-Goldstone Dark Matter Model with CP violation

    Neda Darvishi🇺🇸 · Bohdan Grzadkowski🇵🇱

    We consider an explicitly CP-violating model with two Higgs doublets and one complex singlet scalar. The singlet $S$ is charged under a global $\mathrm{U}(1)$ symmetry which is softly broken by a mass term ${\mu }^2{S}^2+\text{hc}$. Imaginary part of $S$ is a stable dark matter candidate which at the tree level, in the limit of zero momentum transfer, decouples from nucleons naturally satisfying all existing direct detection limits on dark matter scattering cross-section. It is explicitly shown that within this framework in the alignment limit CP-violation is still present in contrast to a popular version of a 2-Higgs doublet model with softly broken $Z_2$ symmetry. In this context, we investigate dark matter implications of the model both with and without CP violation in the scalar sector. In particular, dark matter relic abundance is calculated and the possibility for its indirect detection is discussed.

    hep-phJHEP(2022)·9 citations
19. 19*

    Singlet extensions and W boson mass in the light of the CDF II result

    Kodai Sakurai🇯🇵 · Fuminobu Takahashi🇯🇵 · Wen Yin🇯🇵

    Recently, the CDF collaboration has reported the precise measurement of the W boson mass, $M_W=80433.5\pm 9.4$MeV, based on $8.8$ fb${}^{-1}$ of $\sqrt{s}=1.96$ TeV $p\bar{p}$ collision data from the CDF II detector at the Fermilab Tevatron. This is about $7\sigma$ away from the Standard Model prediction, $M_W^{\mathrm{SM}}=80357\pm 6$MeV. Such a large discrepancy may be partially due to exotic particles that radiatively alter the relation between the W and Z boson masses. In this Letter, we study singlet extensions of the Standard Model focusing on the shift of the W boson mass. In the minimal extension with a real singlet field, using the bounds from the electroweak oblique parameters, B meson decays, LEP, and LHC, we find that the W boson mass shift is at most a few MeV, and therefore it does not alleviate the tension between the CDF II result and the SM prediction. We then examine how much various bounds are relaxed when the singlet is allowed to decay invisibly and find that the increase of the W boson mass does not exceed $5$ MeV due to the bound from the Higgs signal strength. We also discuss phenomenological and cosmological implications of the singlet extensions such as the muon $g-2$ anomaly, axion/hidden photon dark matter, and self-interacting dark radiation as a possible alleviation of the Hubble tension.

    hep-phastro-ph.COhep-exPLB(2022)·93 citations
20. 20*

    Dispersive determination of low energy $\pi K$ interactions

    A. Rodas🇺🇸 · J.R. Peláez🇪🇸

    We summarize the application of dispersion relations for the determination of low energy $\pi K$ interactions. In particular, we present our recent dispersive analyses for the complete study of both $\pi K\to \pi K$ and $\pi \pi \to K\bar{K}$ channels. First, we summarize our approach, we study both channels by using several families of dispersion relations and present the most relevant partial waves. Then we apply the dispersive formalism to the threshold region, where we extract many different low-energy parameters.

    hep-phPoS(2024)·0 citations
21. 21*

    $W$-Boson Mass, Electroweak Precision Tests and SMEFT

    JiJi Fan🇺🇸 · Lingfeng Li🇺🇸 · Tao Liu🇨🇳 · Kun-Feng Lyu🇺🇸

    Recently the CDF collaboration at the Tevatron reported a significant discrepancy between the direct measurement of the $W$-boson mass and its Standard Model (SM) prediction based on electroweak precision tests (EWPTs). In this paper we explore the potential origin of this discrepancy from physics beyond the SM. Explicitly, we work on a set of six-dimensional operators in the SM effective field theory (SMEFT) which are relevant to the EWPTs. By fitting to the data, we demonstrate that an upward shift in $m_W$ is driven by the operator \mathcal{O}_{T}=\frac{1}{2}(H^{\dagger}\overset{\text{\leftrightarrow}}{D}_{\mu}H)^2 with a coefficient $c_T(\mathrm{TeV}/\Lambda {)}^2\gtrsim 0.01$. This suggests that the new physics scale favored by the CDF data should be multiple TeV for tree-level effects and sub TeV for loop-level effects. One simple example is to introduce a hypercharge-free electroweak triplet scalar which can raise the $c_T$ value at tree level. We also study the potential to further test the relevant SMEFT by measuring Higgs-coupling, $m_W$ and other EWPTs at future circular $e^{-}{e}^{+}$ colliders.

    hep-phhep-exPRD(2022)·84 citations
22. 22*

    Correlating Gravitational Waves with $W$-boson Mass, FIMP Dark Matter, and Majorana Seesaw Mechanism

    Xuewen Liu🇨🇳 · Shu-Yuan Guo🇨🇳 · Bin Zhu🇨🇳 · Ying Li🇨🇳

    We study a minimal extension of the Standard Model by introducing three right-handed neutrinos and a new scotogenic scalar doublet, in which the mass splittings between neutral and charged components are responsible for the $W$-boson mass newly measured by the CDF collaboration. This model can not only generate non-vanishing Majorana neutrino masses via the interaction of right-handed neutrinos and scotogenic scalars, but also explain the Universe's missing matter in the form of FIMP dark matter. We also study the influence of the mass splitting on the first order electroweak phase transition, and find that it can further enhance the transition strength and thus induce gravitational waves during the phase transition, which may be detected in the forthcoming detectors such as U-DECIGO.

    hep-phSci.Bull.(2022)·71 citations
23. 23*

    Muon $(g-2)$ and Thermal WIMP DM in ${\mathrm{U}(1)}_{L_{\mu }-L_{\tau }}$ Models

    Seungwon Baek🇰🇷 · Jongkuk Kim🇰🇷 · P. Ko🇰🇷

    The ${\mathrm{U}(1)}_{L_{\mu }-L_{\tau }}$ model is anomaly-free with the Standard Model (SM) fermion content, and can make substantial contributions to the muon $(g-2)$ at the level of $\Delta a_{\mu }\sim O(10)\times 10^{-10}$ for $M_{Z^{\prime }}\sim O(10-100)$ MeV and $g_X\sim (4-8)\times 10^{-4}$. In this light $Z^{\prime }$ region, it was claimed that the model can also incorporate thermal WIMP dark matter (DM) if $M_{\mathrm{DM}}\sim M_{Z^{\prime }}/2$. This setup relies on DM particles annihilating into SM particles through a $Z^{\prime }$-mediated $s$-channel. In this work, we show that this tight relationship between $M_{Z^{\prime }}$ and $M_{\mathrm{DM}}$ can be evaded or nullified both for scalar and spin-1/2 DM by considering the contributions from the dark Higgs boson ($H_1$). The dark Higgs boson plays an important role, not only because it gives mass to the dark photon but also because it introduces additional DM annihilation channels, including new final states such as $H_1{H}_1$, $Z^{\prime }{Z}^{\prime }$, and $Z^{\prime }{H}_1$. As a result, the model does not require a close mass correlation between the $Z^{\prime }$ boson and dark matter $M_{\mathrm{DM}}\sim M_{Z^{\prime }}/2$ any longer, allowing for a broader range of mass possibilities for both scalar and fermionic dark matter types. We explore in great details various scenarios where the $U(1)$ symmetry is either fully broken or partially remains as discrete symmetries, $Z_2$ or $Z_3$. This approach broadens the model's capacity to accommodate various WIMP dark matter phenomena in the light $Z^{\prime }$ region where the muon $(g-2{)}_{\mu }$ makes a sensitive probe of the model.

    hep-phJHEP(2025)·12 citations
24. 24*

    A Model of Vector-like Leptons for the Muon $g-2$ and the $W$ Boson Mass

    Hyun Min Lee🇰🇷 · Kimiko Yamashita🇰🇷

    We consider a simple extension of the Standard Model (SM) with a vector-like lepton and a local $U(1{)}^{\prime }$ symmetry, motivated by the recent experimental anomalies in the muon $g-2$ and the $W$ boson mass. The $U(1{)}^{\prime }$ symmetry is spontaneously broken by the VEVs of the dark Higgs scalar and the second Higgs doublet, giving rise to the mixing between the muon and the vector-like lepton. As a result, we obtain the desirable corrections to the muon $g-2$ and the $W$ boson mass simultaneously, dominantly due to the $Z^{\prime }$ gauge interactions for the vector-like lepton and the second Higgs doublet, respectively. We also discuss the consistency of the model with the $Z$ boson decay width, the Higgs couplings and the dilepton bounds.

    hep-phEPJC(2022)·83 citations
25. 25*

    Type-II Seesaw Triplet Scalar Effects on Neutrino Trident Scattering

    Yu Cheng🇨🇳 · Xiao-Gang He🇹🇼 · Zhong-Lv Huang🇨🇳 · Ming-Wei Li🇨🇳

    In Type-II seesaw model, an electroweak triplet scalar field $\Delta$ with a non-zero vacuum expectation value (vev) $v_{\Delta }$ is introduced to facilitate the generation of small neutrino masses. A non-zero $v_{\Delta }$ also affects the W mass through the electroweak $\rho$ parameter, making it to be less than 1 as predicted by standard model (SM). The component fields in $\Delta$ come along introduce additional contributions to reduce the SM rare neutrino trident scattering cross section. These fields also induce new processes not existed in SM, such as $l_i\to \overline{l_j}{l}_k{l}_l$ and $l_i\to l_j\gamma$. There are severe constraints on these processes which limit the effects on neutrino trident scattering and the $\rho$ parameter and therefore the W mass. The newly measured W mass by CDF makes the central value of $\rho$ parameter to be larger than 1, even larger than previously expected. Combining neutrinoless double beta decay, direct neutrino mass and oscillation data, we find a lower limit for $v_{\Delta }$ as a function of the triplet scalar mass $m_{\Delta }$, $v_{\Delta }>(6.3\sim 8.4)\mathrm{eV}(100\mathrm{GeV}/m_{\Delta })$. To have significant effect on $\rho$ in this model, $v_{\Delta }$ needs to be in the range of a GeV or so. However this implies a very small $m_{\Delta }$ which is ruled out by data. We conclude that the effect of triplet vev $v_{\Delta }$ on the W mass can be neglected. We also find that at 3$\sigma$ level, the deviation of the ratio for Type-II Seesaw to SM neutrino trident scattering cross section predictions is reduced to be below 1, but is restricted to be larger than 0.98.

    hep-phPLB(2022)·82 citations
26. 26*

    Chiral spin symmetry and the QCD phase diagram

    Leonid Ya. Glozman🇦🇹 · Owe Philipsen🇩🇪 · Robert D. Pisarski🇺🇸

    Lattice QCD simulations with chirally symmetric quarks have recently established approximate $SU(2{)}_{CS}$ and $SU(2N_F)$ symmetries of the quantum effective action in a temperature range above the chiral crossover $T_{\mathrm{ch}}$, in which color-electric interactions between quarks dominate the dynamics. We show that such an intermediate temperature range between the chirally broken and plasma regimes is fully consistent with published screening mass spectra, which demonstrate the breakdown of thermal perturbation theory at the crossover between the partonic and the chiral spin symmetric regime at $T_s\sim (2-3)T_{\mathrm{ch}}$. From the known behavior of screening masses with baryon chemical potential, we deduce qualitatively how this chiral spin symmetric band extends into the QCD phase diagram. In the cold and dense region, we propose parity doubled baryons as possible candidates for chiral spin symmetric matter. This represents a special case of quarkyonic matter with confinement and restored chiral symmetry, and can smoothly transform to quark matter at sufficiently high densities. Finally, we discuss the potential of dilepton spectra to identify such matter forms.

    hep-phhep-latnucl-thEPJA(2022)·59 citations
27. 27*

    Electroweak Phase Transition in 2HDM under Higgs, Z-pole, and W precision measurements

    Huayang Song🇨🇳 · Wei Su🇰🇷 · Mengchao Zhang🇨🇳

    In this work we revisit the existence of a strong first order electroweak phase transition (SFOEWPT) and recent $m_W$ precision measurement in the Type-I and Type-II 2HDMs. The O(100) GeV new scalars in 2HDMs are favored by SFOEWPT, which is necessary for electroweak baryogenesis, and observed $m_W$ shift as well. % We find that under current constraints, both Type-I and Type-II 2HDM can explain the SFOEWPT, Z-pole, Higgs precision measurements and $m_W$ precision measurement of CDF-II at same time, and all these precision measurements are sensitive to heavy Higgs mass splitting in 2HDM. The allowed regions are $\Delta m_{A/C}\in (-400,400)GeV,\text{tanb}\in (1,50)$, and $\Delta m_{A/C}\in (-200,300)GeV,\text{tanb}\in (1,12)$ for Type-I and Type-II 2HDM respectively. Furthermore future lepton collider measurements on Higgs and $Z$ boson properties can explore this scenario in more detail or even rule out it.

    hep-phJHEP(2022)·96 citations
28. 28*

    Meson and Glueball spectroscopy within the Graviton Soft-Wall model

    Matteo Rinaldi🇮🇹

    In this contribution we present results of the calculations of several hadronic spectra within the holographic graviton soft-wall (GSW) model. In particular, we studied and compared with data for the ground state and excitations of: glueballs, scalar, vector, axial and pseudo-scalar mesons. The GSW model is found to be capable to describe these observable with only few parameters.

    hep-phhep-thRev.Mex.Fis.Suppl.(2022)·3 citations
29. 29*

    Compared analysis of time-like hyperon form factors

    Andrea Bianconi🇮🇹 · Egle Tomasi-Gustafsson🇫🇷

    Data on hyperon form factors recently obtained from annihilation reactions are compared each other, and to proton and neutron form factors, in terms of two kinematical variables: the transferred momentum square, $q^2$, and the modulus $P$ of the relative momentum between the outgoing baryons. They are critically discussed in terms of possible correlated structures. The present status of the time-like form factor data for baryons is described and suggestions are given on the reactions and the kinematical range where data are desirable in order to clarify the arisen questions.

    hep-phPRC(2022)·7 citations
30. 30*

    ZH production in gluon fusion at NLO in QCD

    Long Chen🇩🇪 · Joshua Davies🇬🇧 · Gudrun Heinrich🇩🇪 · Stephen P. Jones🇬🇧 · Matthias Kerner🇩🇪 · Go Mishima🇯🇵 · Johannes Schlenk🇨🇭 · Matthias Steinhauser🇩🇪

    We present fully differential next-to-leading order results for Higgs production in association with a $Z$ boson in gluon fusion. Our two-loop virtual contributions are evaluated numerically using sector decomposition, including full top-quark mass effects, and supplemented at high $p_T$ by an analytic high-energy expansion to order ($m_Z^4,m_H^4,m_t^{32}$). Using the expanded results we also present a study of the top-quark mass scheme uncertainty at large $p_T$.

    hep-phJHEP(2022)·38 citations
31. 31*

    Full one-loop radiative corrections to $e^{+}{e}^{-}\to H^{+}{H}^{-}$ in the inert doublet model

    Hamza Abouabid🇲🇦 · Abdesslam Arhrib🇲🇦 · Jaouad El Falaki🇲🇦 · Bin Gong🇨🇳 · Wenhai Xie🇨🇳 · Qi-Shu Yan🇨🇳

    We compute the full one-loop radiative corrections for charged scalar pair production $e^{+}{e}^{-}\to H^{+}{H}^{-}$ in the inert doublet model. The on-shell renormalization scheme has been used. We take into account both the weak contributions as well as the soft and hard QED corrections. We compute both the real emission and the one-loop virtual corrections using the Feynman diagrammatic method. The resummed cross section is introduced to cure the Coulomb singularity which occurs in the QED corrections. We have analyzed the parameter space of the inert doublet model in three scenarios after taking into account theoretical constraints, the collider experimental bounds, and dark matter search bounds as well. It is found that the weak interaction dominates the radiative corrections, and its size is determined by the triple Higgs coupling ${\lambda }_{h^0{H}^{+}{H}^{-}}$, which is further connected to the mass of the charged scalar. In the scenario where all the constraints are taken into account, we find that for $\sqrt{s}=250$ GeV and $\sqrt{s}=500$ GeV, the weak corrections are around $-6\%\sim -5\%$ and $-10\%\sim -3\%$, respectively. While for $\sqrt{s}=1000$ GeV, the weak corrections can reach $-15\%\sim +25\%$. The new feature is that the weak corrections can be positive near the threshold when the charged scalar is heavier than 470 GeV. Six benchmark points for future collider searches have been proposed.

    hep-phPRD(2024)·9 citations
32. 32*

    SMEFT Analysis of $m_W$

    Emanuele Bagnaschi🇨🇭 · John Ellis🇬🇧 · Maeve Madigan🇬🇧 · Ken Mimasu🇬🇧 · Veronica Sanz🇪🇸 · Tevong You🇬🇧

    We use the Fitmaker tool to incorporate the recent CDF measurement of $m_W$ in a global fit to electroweak, Higgs, and diboson data in the Standard Model Effective Field Theory (SMEFT) including dimension-6 operators at linear order. We find that including any one of the SMEFT operators ${\mathcal{O}}_{HWB}$, ${\mathcal{O}}_{HD}$, ${\mathcal{O}}_{\ell \ell }$ or ${\mathcal{O}}_{H\ell }^{(3)}$ with a non-zero coefficient could provide a better fit than the Standard Model, with the strongest pull for ${\mathcal{O}}_{HD}$ and no tension with other electroweak precision data. We then analyse which tree-level single-field extensions of the Standard Model could generate such operator coefficients with the appropriate sign, and discuss the masses and couplings of these fields that best fit the CDF measurement and other data. In particular, the global fit favours either a singlet $Z^{\prime }$ vector boson, a scalar electroweak triplet with zero hypercharge, or a vector electroweak triplet with unit hypercharge, followed by a singlet heavy neutral lepton, all with masses in the multi-TeV range for unit coupling.

    hep-phhep-exJHEP(2022)·124 citations
33. 33*

    Violation of custodial symmetry from W-boson mass measurements

    Ayan Paul🇩🇪 · Mauro Valli🇺🇸

    The new measurement of the $W$-boson mass from the CDF collaboration shows a significant tension with the Standard Model prediction. We quantify this discrepancy within a state-of-the-art analysis of electroweak precision data and scrutinize the leading deformations of the Standard Model Effective Field Theory arising at dimension six. We find evidence for a non-zero value of the $T$ parameter, i.e. for a novel source of violation of custodial symmetry, pointing to physics beyond the Standard Model at the 4.5$\sigma$ level. We contextualize the implications of our findings in light of other present anomalies in Particle Physics.

    hep-phhep-exPRD(2022)·75 citations
34. 34*

    New physics effects on the $W$-boson mass from a doublet extension of the SM Higgs sector

    Henning Bahl🇺🇸 · Johannes Braathen🇩🇪 · Georg Weiglein🇩🇪

    Recently, the CDF collaboration has reported a new precision measurement of the $W$-boson mass, $M_W$, showing a large deviation from the value predicted by the Standard Model (SM). In this paper, we analyse possible new physics contributions to $M_W$ from extended Higgs sectors. We focus on the Two-Higgs-Doublet Model (2HDM) as a concrete example. Employing predictions for the electroweak precision observables in the 2HDM at the two-loop level and taking into account further theoretical and experimental constraints, we identify parameter regions of the 2HDM in which the prediction for $M_W$ is close to the new CDF value. We assess the compatibility of these regions with precision measurements of the effective weak mixing angle and the total width of the $Z$ boson.

    hep-phPLB(2022)·105 citations
35. 35*

    Oblique Lessons from the $W$ Mass Measurement at CDF II

    Pouya Asadi🇺🇸 · Cari Cesarotti🇺🇸 · Katherine Fraser🇺🇸 · Samuel Homiller🇺🇸 · Aditya Parikh🇺🇸

    The CDF collaboration recently reported a new precise measurement of the $W$ boson mass $M_W$ with a central value significantly larger than the SM prediction. We explore the effects of including this new measurement on a fit of the Standard Model (SM) to electroweak precision data. We characterize the tension of this new measurement with the SM and explore potential beyond the SM phenomena within the electroweak sector in terms of the oblique parameters $S$, $T$ and $U$. We show that the large $M_W$ value can be accommodated in the fit by a large, nonzero value of $U$, which is difficult to construct in explicit models. Assuming $U=0$, the electroweak fit strongly prefers large, positive values of $T$. Finally, we study how the preferred values of the oblique parameters may be generated in the context of models affecting the electroweak sector at tree- and loop-level. In particular, we demonstrate that the preferred values of $T$ and $S$ can be generated with a real SU(2)${}_L$ triplet scalar, the humble "swino," which can be heavy enough to evade current collider constraints, or by (multiple) species of a singlet-doublet fermion pair. We highlight challenges in constructing other simple models, such as a dark photon, for explaining a large $M_W$ value, and several directions for further study.

    hep-phPRD(2023)·121 citations
36. 36*

    Higgs physics confronts the $M_W$ anomaly

    Luca Di Luzio🇮🇹 · Ramona Gröber🇮🇹 · Paride Paradisi🇮🇹

    The recent high-precision measurement of the $W$ mass by the CDF collaboration is in sharp tension with the Standard Model prediction as obtained by the electroweak fit. If confirmed, this finding can only be explained in terms of new physics effects. In this work, we point out a generic connection between the $M_W$ anomaly and Higgs physics observables such as $h\to \gamma \gamma ,Z\gamma$ and the ratio $h\to ZZ/WW$. Moreover, we systematically classify new physics scenarios which can address the $M_W$ anomaly via a tree-level contribution to the $\hat{T}$ parameter. These include a real scalar triplet, a scalar quadruplet with the same hypercharge of the Higgs doublet, a $Z^{\prime }$ boson, a vector triplet with unit hypercharge and a vector boson with the gauge quantum numbers of the Higgs doublet. These solutions to the $M_W$ anomaly are characterized by new physics states which are typically too heavy to be discovered in direct searches, but which might leave their imprints in Higgs physics.

    hep-phhep-exPLB(2022)·87 citations
37. 37*

    Precise calculation of the W boson pole mass beyond the Standard Model with FlexibleSUSY

    Peter Athron🇨🇳 · Markus Bach🇩🇪 · Douglas H.J. Jacob🇦🇺 · Wojciech Kotlarski🇵🇱 · Dominik Stöckinger🇩🇪 · Alexander Voigt🇩🇪

    We present an updated calculation of the W boson pole mass in models beyond the Standard Model with FlexibleSUSY. The calculation has a decoupling behaviour and allows for a precise W pole mass prediction up to large new physics scales. We apply the calculation to several Standard Model extensions, including the MRSSM where we show that it can be compatible with large corrections to the W boson mass that would be needed to fit the recent 2022 CDF measurement.

    hep-phPRD(2022)·112 citations
38. 38*

    Relativistic nonlinear axion magnetohydrodynamics

    Timur Yu. Alpin🇷🇺 · Alexander B. Balakin🇷🇺 · Alexei V. Vorohov🇷🇺

    The new nonlinear axionically extended version of the general relativistic magnetohydrodynamics is formulated. The self-consistent formalism of this theory is based on the introduction into the Lagrangian of the new unified scalar invariant, which is quadratic in the Maxwell tensor, and contains two periodic functions of the pseudoscalar (axion) field. The constructed unified invariant and the elaborated nonlinear theory as a whole, are invariant with respect to two symmetries: first, the discrete symmetry associated with the properties of the axion field; second, the Jackson's SO(2) type symmetry intrinsic for the electromagnetism. The subsystem of the master equations, which describes the velocity four-vector of the hydrodynamic flow, is constructed in the framework of Eckart's theory of viscous heat-conducting fluid. The axionically extended nonlinear Faraday, Gauss and Ampere equations are supplemented by the ansatz about the large electric conductivity of the medium, which is usually associated with vanishing of the electric field. We have suggested two essentially new nonlinear models, in the framework of which the anomalous electric conductivity is being compensated by the appropriate behavior of the finite pseudoscalar (axion) field, providing the electric field in the magnetohydrodynamic flow to be finite (either to be proportional to the magnetic field, or to the angular velocity of the medium rotation)

    hep-phgr-qcSpace Time and Fundamental Interactions, …·0 citations
39. 39*

    Speculations on the W-Mass Measurement at CDF

    Jiayin Gu🇨🇳 · Zhen Liu🇺🇸 · Teng Ma🇮🇱 · Jing Shu🇨🇳

    The W Mass determination at the Tevatron CDF experiment reported a deviation from the SM expectation at 7$\sigma$ level. We discuss a few possible interpretations and their collider implications. We perform electroweak global fits under various frameworks and assumptions. We consider three types of electroweak global fits in the effective-field-theory framework: the $S$-$T$, the $S$-$T$-$\delta G_F$, and the eight-parameter flavor-universal one. We discuss the amounts of tensions between different $m_W$ measurements reflected in these fits and the corresponding shifts in central values of these parameters. With these electroweak fit pictures in hand, we present a few different classes of models and discuss their compatibility with these results. We find that while explaining the $m_W$ discrepancy, the single gauge boson extensions face strong LHC direct search constraints unless the $Z^{\prime }$ is fermiophobic (leptophobic) which can be realized if extra vector fermions (leptons) mix with the SM fermions (leptons). Vector-like top partners can partially generate the needed shift to the electroweak observables. The compatibility with top squark is also studied in detail. We find non-degenerate top squark soft masses enhance the needed operator coefficients, enabling an allowed explanation compatible with current LHC measurements. Overall, more theory and experimental developments are highly in demand to reveal the physics behind this discrepancy.

    hep-phhep-exCPC(2022)·73 citations
40. 40*

    Extra $W$-Boson Mass from a D3-Brane

    Jonathan J. Heckman🇺🇸

    Motivated by the recent CDF measurement of the $W$-boson mass, we study string-based particle physics models which can accommodate this deviation from the Standard Model. We consider an F-theory GUT in which the visible sector is realized on intersecting 7-branes, and extra sector states arise from a probe D3-brane near an E-type Yukawa point. The D3-brane worldvolume naturally realizes a strongly coupled sector which mixes with the Higgs. In the limit where some extra sector states get their mass solely from Higgs vevs, this leads to a contribution to the $\rho$ parameter which is too large, but as the D3-brane is separated from the 7-brane stack, this effect is suppressed, leading to O(1) - O(10) TeV scale extra sector states and a correction to $\rho$ which would be in accord with the CDF result. We also estimate the contribution to the oblique electroweak parameter $S$, and find that it is compatible with existing constraints. This also leads to additional signatures, including diphoton resonances (as well as other diboson final states) in the O(1) - O(10) TeV range.

    hep-phhep-exhep-thPLB(2022)·79 citations
41. 41*

    Correlating $W$-Boson Mass Shift with Muon $g-2$ in the 2HDM

    K.S. Babu (Oklahoma State University)🇺🇸 · Sudip Jana (Max Planck Institute, Heidelberg)🇩🇪 · Vishnu P.K. (Oklahoma State University)

    We show an interesting correlation between the recent high precision measurement of the $W$-boson mass by the CDF collaboration and the muon $(g-2)$ anomaly in the context of the two Higgs doublet model. One-loop diagrams involving the exchange of neutral scalar bosons can explain the muon $(g-2)$, which however requires significant mass splittings among members of the second Higgs doublet. These splittings also generate a positive shift in the mass of the $W$-boson, consistent with the recent CDF measurement. The charged and neutral scalars of the model cannot be heavier than about 600 GeV for a simultaneous explanation of the two anomalies. The entire parameter space of the model can be tested at the LHC by a combination of same sign dimuon signals in $pp\to ({\mu }^{+}{\mu }^{+}jj+{E/}_T)$ and $pp\to ({\mu }^{+}{\mu }^{-}{\tau }^{+}{\tau }^{-}+X)$ signals.

    hep-phhep-exPRL(2022)·118 citations
42. 42*

    Octions: An $E_8$ description of the Standard Model

    Corinne A. Manogue🇺🇸 · Tevian Dray🇺🇸 · Robert A. Wilson🇬🇧

    We interpret the elements of the exceptional Lie algebra ${\mathfrak{e}}_{8(-24)}$ as objects in the Standard Model, including lepton and quark spinors with the usual properties, the Standard Model Lie algebra $\mathfrak{su}(3)+\mathfrak{su}(2)+\mathfrak{u}(1)$, and the Lorentz Lie algebra $\mathfrak{so}(3,1)$. Our construction relies on identifying a complex structure on spinors and then working in the enveloping algebra. The resulting model naturally contains GUTs based on $SO(10)$ (Georgi--Glashow), $SU(5)$ (Georgi), and $SU(4)\times SU(2)\times SU(2)$ (Pati--Salam). We then briefly speculate on the role of the remaining elements of ${\mathfrak{e}}_8$, and propose a mechanism leading to exactly three generations of particles.

    hep-phhep-thJ.Math.Phys.(2022)·31 citations
43. 43*

    Asymmetric transverse momentum broadening in an inhomogeneous medium

    Yu Fu🇨🇳 · Jorge Casalderrey-Solana🇪🇸 · Xin-Nian Wang🇨🇳

    Gradient jet tomography in high-energy heavy-ion collisions utilizes the asymmetric transverse momentum broadening of a propagating parton in an inhomogeneous medium. Such broadening is studied within a path integral description of the evolution of the Wigner distribution for a propagating parton in medium. Going beyond the eikonal approximation of multiple scattering, the evolution operator in the transverse direction can be expressed as the functional integration over all classical trajectories of a massive particle with the light-cone momentum $\omega$ as its mass. With a dipole approximation of the Wilson line correlation function, evolution with the light-cone time $t$ is determined by the jet transport coefficient $\hat{q}$ that can vary with space and time. In a uniform medium with a constant ${\hat{q}}_0$, the analytical solution to the Wigner distribution becomes a typical drifted Gaussian in both transverse momentum and coordinate with the diffusion width $\sqrt{{\hat{q}}_{0}t}$ and $\sqrt{{\hat{q}}_0{t}^3/3{\omega }^2}$, respectively. In the case of a simple Gaussian-like transverse inhomogeneity with a spatial width $\sigma$ on top of a uniform medium, the final asymmetrical momentum distribution can be calculated semi-analytically. The transverse asymmetry defined for jet gradient tomography that characterizes the asymmetrical distribution is found to linearly correlate with the initial transverse position of the propagating parton within the domain of the inhomogeneity. It decreases with the parton energy $\omega$, increases with the propagation time initially and saturates when the diffusion distance is much larger than the size of the inhomogeneity or $t^3\gg 3{\omega }^2{\sigma }^2/{\hat{q}}_0$. The transverse momentum broadening due to the inhomogeneity also saturates at late time in contrast to the continued increase with time if the drifted diffusion in space is ignored.

    hep-phnucl-thPRD(2023)·32 citations
44. 44*

    Self-tuning inflation

    Polina Petriakova🇷🇺 · Sergey G. Rubin🇷🇺

    We develop an inflationary model without small parameters on the basis of multidimensional $f(R)$ gravity with a minimally coupled scalar field. The model is described by two stages of space expansion. The first one begins at energy scales about the D-dimensional Planck mass and ends with the de Sitter metric of our space and the maximally symmetric extra dimensions. In the following, the quantum fluctuations produce a wide set of inhomogeneous extra metrics in causally disconnected regions quickly generated in the de Sitter space. We find a specific extra space metric that leads to the effective Starobinsky model that fits the observational data.

    ↳ gr-qchep-phhep-thEPJC(2022)·5 citations
45. 45*

    Using $\gamma$-ray observations of dwarf spheroidal galaxies to test the possible common origin of the W-boson mass anomaly and the GeV $\gamma$-ray/antiproton excesses

    Ben-Yang Zhu🇨🇳 · Shang Li🇨🇳 · Ji-Gui Cheng🇨🇳 · Xiao-Song Hu🇨🇳 · Rong-Lan Li🇨🇳 · Yun-Feng Liang🇨🇳

    A recent result from Fermilab suggests that the measured W-boson mass deviates from the prediction of the Standard Model (SM) with a significance of $>7\sigma$, and there may exist new physics beyond the SM. It is proposed that the inert two Higgs doublet model (i2HDM) can well explain the new W-boson mass. Meanwhile, the lightest neutral scalar $S$ in the i2HDM can be stable and play the role of dark matter with a preferred dark matter mass of $\sim 54-74$ GeV. It is also found that part of the parameter space of this model can explain both the Galactic center GeV gamma-ray excess detected by $Fermi$-LAT and the GeV antiproton excess detected by AMS-02 through a $SS\to W{W}^{\ast }$ annihilation. In this paper, we aim to test the possible common i2HDM origin of the three anomaly/excesses using the $Fermi$-LAT observations of Milky Way dwarf spheroidal (dSph) galaxies. We perform single and stacking analyses on 19 dSphs that have J-factor measurements. We find that our upper limits are below the favored parameters and seems to be able to exclude the possibility of a common origin of the three anomaly/excesses. However, because the J-factor measurements include relatively large uncertainties, which come from the measurements of stellar kinematics, whether this model could be reliably excluded needs to be further confirmed by future observations.

    ↳ astro-ph.HEhep-phPRD(2023)·42 citations
46. 46*

    Spurious poles in a finite volume

    Jin-Yi Pang🇨🇳 · Martin Ebert🇩🇪 · Hans-Werner Hammer🇩🇪 · Fabian Müller🇩🇪 · Akaki Rusetsky🇩🇪 · Jia-Jun Wu🇨🇳

    Using effective-range expansion for the two-body amplitudes may generate spurious sub-threshold poles outside of the convergence range of the expansion. In the infinite volume, the emergence of such poles leads to the inconsistencies in the three-body equations, e.g., to the breakdown of unitarity. We investigate the effect of the spurious poles on the three-body quantization condition in a finite volume and show that it leads to a peculiar dependence of the energy levels on the box size $L$. Furthermore, within a simple model, it is demonstrated that the procedure for the removal of these poles, which was recently proposed in Ref.[1] in the infinite volume, can be adapted to the finite-volume calculations. The structure of the exact energy levels is reproduced with an accuracy that systematically improves order by order in the EFT expansion.

    ↳ hep-lathep-phnucl-thJHEP(2022)·9 citations
47. 47*

    Very High-energy Afterglow Emission of GRB 190829A: Evidence for Its Hadronic Origin?

    Sarira Sahu🇲🇽 · Isabel Abigail Valadez Polanco🇲🇽 · Subhash Rajpoot🇺🇸

    The detection of multi-TeV gamma-rays from the afterglow phase of GRB 190829A by High Energy Stereoscopic System (H.E.S.S.) telescope is an addition to the already existing list of two more GRBs observed in the very high energy (VHE) gamma-rays in recent years. Jets of blazars and GRBs have many similarities and the photohadronic model is very successful in explaining the VHE gamma-ray spectra from the high energy blazars. Recently, the photohadronic model has been successfully applied to study the sub-TeV gamma-rays from the afterglow phases of GRB 180720B and GRB 190114C. We employed this model again to explain the VHE spectra observed for the two consecutive nights from GRB 190829A. We show that the spectra of GRB 190829A can be due to the interactions of high energy protons with the synchrotron self-Compton photons in the forward shock region of the GRB jet, similar to the low emission state of the VHE flaring events of high energy blazars. We speculate that, if in future, it is possible to observe the VHE gamma-ray spectra from nearby GRBs in their afterglow phases, then some of them could only be explained by employing two different spectral indices. If confirmed, such VHE spectra could be interpreted as a result of the interactions of the high energy protons with the photons, both from the synchrotron background and the synchrotron self-Compton background in the forward shock region.

    ↳ astro-ph.HEhep-phApJ(2022)·19 citations
48. 48*

    Exploring the Fate of Stellar Core Collapse with Supernova Relic Neutrinos

    Yosuke Ashida🇺🇸 · Ken'ichiro Nakazato🇯🇵

    Core collapse of massive stars leads to different fates for various physical factors, which gives different spectra of the emitted neutrinos. We focus on the supernova relic neutrinos (SRNs) as a probe to investigate the stellar collapse fate. We present the SRN fluxes and event rate spectra at a detector for three resultant states after stellar core collapse, the typical mass neutron star, the higher mass neutron star, or the failed supernova forming a black hole, based on different nuclear equations of state. Then possible SRN fluxes are formed as mixtures of the three components. We also show the expected sensitivities at the next-generation water-based Cherenkov detectors, SK-Gd and Hyper-Kamiokande, as constraining the mixture fractions. This study provides a practical example of extracting astrophysical constraints through SRN measurement.

    ↳ astro-ph.HEhep-phApJ(2022)·22 citations
49. 49*

    Hyperons, deconfinement and the speed of sound in neutron stars

    R. M. Aguirre🇦🇷

    The effects of the presence of hyperons and a phase transition to deconfined quark matter on the speed of sound in neutron stars is investigated. For this purpose a composite description consisting of a model of the covariant field theory of hadrons and one for unbound quarks are used. A phase transition with continuous and monotonous variation of the equation of state is assumed. The predictions are contrasted with recent observational data on isolated neutron stars as well as on binary systems. Only one candidate is finally obtained from six different descriptions. According to the present calculations the onset of the hyperons causes the equilibrium speed of sound to exceed the conformal limit. Qualitative agreement with recent work about the influence of the speed of sound on the g-modes of oscillation in neutron stars is obtained.

    ↳ nucl-thgr-qchep-phPRD(2022)·10 citations
50. 50*

    Entanglement in interacting quenched two-body coupled oscillator system

    Sayantan Choudhury🇮🇳 · Rakshit Mandish Gharat🇮🇳 · Saptarshi Mandal🇮🇳 · Nilesh Pandey🇮🇳 · Abhishek Roy🇮🇳 · Partha Sarker🇧🇩

    In this work, we explore the effects of a quantum quench on the entanglement measures of a two-body coupled oscillator system having quartic interaction. We use the invariant operator method, under a perturbative framework, for computing the ground state of this system. We give the analytical expressions for the total and reduced density matrix of the system having non-Gaussian, quartic interaction terms. Using this reduced density matrix, we show the analytical calculation of two entanglement measures viz., Von Neumann entanglement entropy using replica trick and Renyi entanglement entropy. Further, we give a numerical estimate of these entanglement measures with respect to the dimensionless parameter $(t/\delta t$) and show its behaviour in the three regimes, i.e; late time behaviour, around the quench point and the early time behaviour. We comment on the variation of these entanglement measures for different orders of coupling strength. The variation of Renyi entropy of different orders has also been discussed.

    ↳ hep-thcond-mat.stat-mechgr-qchep-ph+1PRD(2022)·10 citations
51. 51*

    Exploring the landscape of (anti-) de Sitter and Minkowski solutions: group manifolds, stability and scale separation

    David Andriot🇫🇷 · Ludwig Horer🇦🇹 · Paul Marconnet🇫🇷

    We classified in arXiv:2201.04152 certain 10d supergravity solutions with a 4d de Sitter, Minkowski or anti-de Sitter spacetime. We then found new solutions in previously unexplored classes. In this paper we study their properties, compare them to swampland conjectures, and make new observations. Using new numerical tools, we first identify all Lie algebras underlying the 6d group manifolds, allowing us to discuss their compactness. We then investigate scale separation, and prove related no-go theorems. Last but not least, we automatize and analyze the stability of all solutions. This leads us to propose the Massless Minkowski Conjecture, claiming the systematic presence of a 4d massless scalar field.

    ↳ hep-thgr-qchep-phmath-ph+1JHEP(2022)·37 citations
52. 52*

    First principles cosmology of the Standard Model epoch

    Daniel Friedan🇺🇸

    This is a short summary of a project to construct a first principles cosmology of the Standard Model epoch, the period starting shortly before the electro-weak transition. The cosmology is derived from a simple initial state entirely within the SM and General Relativity. The initial state is semi-classical -- concentrated near a classical solution of the SM equations of motion -- and is precisely specified by a few simple conditions. The dark matter is a classical effect, a coherent state of the SU(2)-weak gauge field and the Higgs field. The leading order, classical universe contains only the dark matter. Ordinary matter is a correction due to the fluctuations of the SM fields around the classical trajectory. The initial state produces a homogeneous, isotropic, flat universe. There are no adjustable parameters. No physics beyond the SM is invoked. Only the classical calculations have been done so far. The time evolution of the fluctuations remains to be calculated.

    ↳ astro-ph.COhep-phhep-th1 citation

* 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.