Thu·Aug 17, 2023Thursday·August 17, 2023

1. 01*

   Probing new physics with charge asymmetries in 2 same-sign leptons plus jets final states at the LHC

   Ernesto Arganda🇪🇸 · Leandro Da Rold🇦🇷 · Aurelio Juste🇪🇸 · Anibal D. Medina🇦🇷 · Rosa M. Sandá Seoane🇪🇸

   We study the impact of new physics models in the charge asymmetry defined for LHC final states consisting of two same-sign leptons (2SS$l$, with $l=e,\mu$) plus jets ($N_{\text{jets}}\ge 2$), with a center-of-mass energy of $\sqrt{s}=13$ TeV, where the main SM contribution is $t\bar{t}W$ production. Concretely, we consider three different new physics sources for the charge asymmetries: a heavy neutral scalar/pseudoscalar arising from the general two Higgs doublet model, an effective theory with dimension-6 four-quark operators, and a simplified $R$-parity-violating supersymmetric model with electroweakino production (higgsino-like or wino-like). We propose measuring the charge asymmetries differentially with respect to several kinematic observables, and inclusively/exclusively with the number of $b$-tagged jets in the final state ($N_b\ge \{1,2,3\}$). Results are compared with the SM prediction using the ${\chi }^2$ criteria, expressing sensitivity in terms of the normal Gaussian significance. We show that some of the proposed new physics scenarios can be probed at the LHC even for the already recorded integrated luminosity of 139 fb${}^{-1}$. Finally, we also estimate the prospects for the potential LHC sensitivity to the considered new physics models in its high-luminosity phase.

   hep-phJHEP(2024)·3 citations
2. 02*

   ${\tau }^{-}\to {\pi }^{-}\eta {\nu }_{\tau }$ decay induced by QED one-loop effects

   Gerardo Hernández-Tomé🇲🇽 · Gabriel López Castro🇲🇽 · Diego Portillo-Sánchez🇲🇽

   The ${\tau }^{-}\to {\pi }^{-}\eta {\nu }_{\tau }$ decay is forbidden in the Standard Model in the limit of exact $G$-parity, it becomes a rare decay due to isospin symmetry breaking and it is very sensitive to the effects of effective scalar interactions. Since the parameters driving isospin breaking, $(m_d-m_u)/(m_s-\bar{m})$ and $\alpha$, are of the same order, one may expect their $G$-parity breaking effects in this decay can be of similar magnitudes. In this work, we evaluate the effects of isospin-breaking amplitudes originated from a virtual photon at one-loop in a resonance dominance model to describe photon-hadron interactions. We find that these effects can shift the leading SM predictions based on the $u-d$ quark mass difference by roughly $12\%$, and should be taken into consideration in a precision comparison of theory and experiment in order to draw meaningful conclusions on New Physics. The effects in the rate of the analogous ${\tau }^{-}\to {\pi }^{-}{\eta }^{\prime }{\nu }_{\tau }$ decay can be larger ($\sim$ $78\%$), under the approximations assumed in this model.

   hep-phPRD(2023)·4 citations
3. 03*

   Hidden Sector Dark Matter Realized as a Twin of the Visible Universe With Zero Higgs Vacuum Expectation

   Stephen L. Adler🇺🇸

   We propose that the universe contains two identical sets of particles and gauge interactions, coupling only through gravitation, which differ by their Higgs potentials. We postulate that because of underlying symmetries, the two sectors when uncoupled have Higgs potentials that lie at the boundary between phases with nonzero and zero Higgs vacuum expectation. Turning on the coupling between the two sectors can break the degeneracy, pushing the Higgs potential in one sector into the domain of nonzero Higgs expectation (giving the visible sector), and pushing the Higgs potential in the other sector into the domain of zero Higgs expectation (giving the dark sector). The least massive baryon in the dark sector will then be a candidate self-interacting dark matter particle.

   hep-phastro-ph.COastro-ph.GAgr-qc+1International Journal of Modern Physics D…·1 citation
4. 04*

   Drag force and heavy quark potential in a rotating background

   Jun-Xia Chen🇨🇳 · De-Fu Hou🇨🇳 · Hai-Cang Ren🇨🇳

   We explored the gravity dual of a rotating quark-gluon plasma by transforming the boundary coordinates of the large black hole limit of Schwarchild-${\text{AdS}}_5$ metric. The Euler-Lagrange equation of the Nambu-Goto action and its solution become more complex than those without rotation. For small angular velocity, we obtained an analytical form of the drag force acting on a quark moving in the direction of the rotation axis and found it stronger than that without rotation. We also calculated the heavy quark potential under the same approximation. For the quarkonium symmetric with respect to the rotation axis, the depth of the potential is reduced by the rotation. For the quarkonium oriented in parallel to the rotation axis, the binding force is weakened and the force range becomes longer. We also compared our holographic formulation with others in the literature.

   hep-phhep-thJHEP(2024)·20 citations
5. 05*

   Chiral kinetic theory with self-energy corrections and neutrino spin Hall effect

   Naoki Yamamoto🇯🇵 · Di-Lun Yang🇹🇼

   We systematically derive the chiral kinetic theory for chiral fermions with collisions, including the self-energy corrections, from quantum field theories. We find that the Wigner functions and chiral kinetic equations receive both the classical and quantum corrections from the self-energies and their spacetime gradients. We also apply this formalism to study nonequilibrium neutrino transport due to the interaction with thermalized electrons and nucleons, as realized in core-collapse supernovae. We derive neutrino currents along magnetic fields and neutrino spin Hall effect induced by the density gradient at first order in the Fermi constant $G_{\mathrm{F}}$ for anisotropic neutrino distributions.

   hep-phastro-ph.HEnucl-thPRD(2024)·12 citations
6. 06*

   Generalized parton distributions of gluon in proton: a light-front quantization approach

   Bolang Lin🇨🇳 · Sreeraj Nair🇨🇳 · Siqi Xu🇨🇳 · Zhi Hu🇨🇳 · Chandan Mondal🇨🇳 · Xingbo Zhao🇨🇳 · James P.Vary🇺🇸

   We solve for the gluon generalized parton distributions (GPDs) inside the proton, focusing specifically on leading twist chiral-even GPDs. We obtain and employ the light-front wavefunctions (LFWFs) of the proton from a light-front quantized Hamiltonian with Quantum Chromodynamics input using basis light-front quantization (BLFQ). Our investigation incorporates the valence Fock sector with three constituent quarks and an additional Fock sector, encompassing three quarks and a dynamical gluon. We examine the GPDs within impact parameter space and evaluate the $x$-dependence of the transverse square radius. We find that the transverse size of the gluon at lower-$x$ is larger than that of the quark, while it exhibits opposite behavior at large-$x$. Using the proton spin sum rule, we also determine the relative contributions of quarks and the gluon to the total angular momentum of the proton.

   hep-phnucl-thPLB(2023)·32 citations
7. 07*

   Hierarchical High-Point Energy Flow Network for Jet Tagging

   Wei Shen🇨🇳 · Daohan Wang🇰🇷 · Jin Min Yang🇨🇳

   Jet substructure observable basis is a systematic and powerful tool for analyzing the internal energy distribution of constituent particles within a jet. In this work, we propose a novel method to insert neural networks into jet substructure basis as a simple yet efficient interpretable IRC-safe deep learning framework to discover discriminative jet observables. The Energy Flow Polynomial (EFP) could be computed with a certain summation order, resulting in a reorganized form which exhibits hierarchical IRC-safety. Thus inserting non-linear functions after the separate summation could significantly extend the scope of IRC-safe jet substructure observables, where neural networks can come into play as an important role. Based on the structure of the simplest class of EFPs which corresponds to path graphs, we propose the Hierarchical Energy Flow Networks and the Local Hierarchical Energy Flow Networks. These two architectures exhibit remarkable discrimination performance on the top tagging dataset and quark-gluon dataset compared to other benchmark algorithms even only utilizing the kinematic information of constituent particles.

   hep-phhep-exJHEP(2023)·15 citations
8. 08*

   Isosinglet vectorlike leptons at $e^{+}{e}^{-}$ colliders

   Prudhvi N. Bhattiprolu🇺🇸 · Stephen P. Martin🇺🇸 · Aaron Pierce🇺🇸

   We study weak isosinglet vectorlike leptons that decay through a small mixing with the tau lepton, for which the discovery and exclusion reaches of the Large Hadron Collider and future proposed hadron colliders are limited. We show how an $e^{+}{e}^{-}$ collider may act as a discovery machine for these ${\tau }^{\prime }$ particles, demonstrate that the ${\tau }^{\prime }$ mass peak can be reconstructed in a variety of distinct signal regions, and explain how the ${\tau }^{\prime }$ branching ratios may be measured.

   hep-phPRD(2024)·7 citations
9. 09*

   Comments on "On the Dirac-Majorana neutrinos distinction in four-body decays" (arXiv:2305.14140 [hep-ph], Phys. Rev. D 109, no.3, 033005 (2024))

   C. S. Kim🇰🇷 · M. V. N. Murthy🇮🇳 · Dibyakrupa Sahoo🇵🇱

   In arXiv:2305.14140 [hep-ph] the authors analyze the radiative leptonic decay ${\ell }^{-}\to {\nu }_{\ell }{\overline{\nu }}_{{\ell }^{\prime }}{\ell }^{\prime -}\gamma$ to distinguish between Dirac and Majorana nature of neutrinos. They utilize the back-to-back kinematics for this purpose, a special kinematic configuration which we first proposed in our paper arXiv:2106.11785 [hep-ph]. Here we point out how and why their analysis of the back-to-back configuration is incorrect. This makes their conclusion and comments invalid and untenable.

   hep-ph1 citation
10. 10*

    Energy dependence of proton-proton elastic scattering at large momentum transfer

    Erasmo Ferreira🇧🇷 · Anderson Kendi Kohara🇵🇱

    The measurements of proton-proton elastic scattering for large momentum transfer at energies in the range $\approx$ 20 to 60 GeV show a simple behaviour of form $d\sigma /dt\approx \mathrm{const}|t{|}^{-8}$, apparently with no energy dependence. In the present work detailed analysis of the data shows a decrease of the magnitude of the tail with the energy, still with preservation of the power $|t{|}^{-8}$. The analysis allows the definition of a band for the energy dependence with the form of a power of the strong coupling ${\alpha }_S^{1.57}$. The rate of decrease describes very well the data at the distant energy $\sqrt{s}$ = 13 TeV, with reduction of the cross section by a factor 5.71. This result gives prediction for new experiments at high energies, and opens important question for theoretical investigation.

    hep-phPLB(2023)·0 citations
11. 11*

    Detecting Quadratically Coupled Ultra-light Dark Matter with Stimulated Annihilation

    Yuanlin Gong🇨🇳 · Xin Liu🇨🇳 · Lei Wu🇨🇳 · Qiaoli Yang🇨🇳 · Bin Zhu🇨🇳

    Ultra-light Dark Matter (ULDM) is one of the most promising DM candidates. Due to the Bose enhancement, we find the annihilation rate of the ULDM in the presence of background photon radiation can be greatly enhanced and produce a distinctive reflected electromagnetic wave with an angular frequency equal to the ULDM mass. We propose to utilize such stimulated annihilation to probe the ULDM with the electromagnetic quadratic coupling by emitting a beam of radio into space. With a power of 50 MW emitter, we forecast the sensitivity of quadratic coupling in different local halo models for low-frequency radio telescopes, such as LOFAR, UTR-2 and ngLOBO.

    hep-phastro-ph.COPRD(2024)·9 citations
12. 12*

    Minimal $SU(5)$ GUTs with vectorlike fermions

    Stefan Antusch🇨🇭 · Kevin Hinze🇨🇭 · Shaikh Saad🇨🇭

    In this work, we attempt to answer the question, "What is the minimal viable renormalizable $SU(5)$ GUT with representations no higher than adjoints?". We find that an $SU(5)$ model with a pair of vectorlike fermions $5_F+{\overline{5}}_F$, as well as two copies of $15_H$ Higgs fields, is the minimal candidate that accommodates for correct charged fermion and neutrino masses and can also address the matter-antimatter asymmetry of the universe. Our results show that the presented model is highly predictive and will be fully tested by a combination of upcoming proton decay experiments, collider searches, and low-energy experiments in search of flavor violations. Moreover, we also entertain the possibility of adding a pair of vectorlike fermions $10_F+{\overline{10}}_F$ or $15_F+{\overline{15}}_F$ (instead of a $5_F+{\overline{5}}_F$). Our study reveals that the entire parameter space of these two models, even with minimal particle content, cannot be fully probed due to possible longer proton lifetime beyond the reach of Hyper-Kamiokande.

    hep-phPRD(2023)·16 citations
13. 13*

    Photon-Dark Photon Conversion with Multiple Level Crossings

    Nirmalya Brahma🇨🇦 · Asher Berlin🇺🇸 · Katelin Schutz🇨🇦

    Dark photons can oscillate into Standard Model (SM) photons via kinetic mixing. The conversion probability depends sensitively on properties of the ambient background, such as the density and electromagnetic field strength, which cause the SM photon to acquire an in-medium effective mass. Resonances can enhance the conversion probability when there is a level-crossing between the dark photon and background-dependent SM photon states. In this work, we show that the widely used Landau-Zener (LZ) approximation breaks down when there are multiple level-crossings due to a non-monotonic SM photon potential. Phase interference effects, especially when the dark photon mass is close to an extremum of the SM photon effective mass, can cause deviations from the LZ approximation at the level of a few orders of magnitude in the conversion probability. We present an analytic approximation that is valid in this regime and that can accurately predict the conversion probabilities in a wide range of astrophysical environments.

    hep-phastro-ph.COPRD(2023)·24 citations
14. 14*

    Searching for axions with kaon decay at rest

    Yohei Ema🇺🇸 · Zhen Liu🇺🇸 · Ryan Plestid🇺🇸

    We describe a novel search strategy for axions (or hadronically coupled axion-like particles) in the mass range of $m_a\lesssim 350\mathrm{MeV}$. The search relies on kaon decay at rest, which produces a mono-energetic signal in a large volume detector (e.g.\ a tank of liquid scintillator) from axion decays $a\to \gamma \gamma$ or $a\to e^{+}{e}^{-}$. The decay modes $K^{+}\to {\pi }^{+}a$ and $a\to \gamma \gamma$ are induced by the axion's coupling to gluons, which is generic to any model which addresses the strong CP problem. We recast a recent search from MicroBooNE for $e^{+}{e}^{-}$ pairs, and study prospects at JSNS${}^2$ and other near-term facilities. We find that JSNS${}^2$ will have world-leading sensitivity to hadronically coupled axions in the mass range of $40\mathrm{MeV}\lesssim m_a\lesssim 350\mathrm{MeV}$.

    hep-phhep-exPRD(2024)·9 citations
15. 15*

    2-index chiral gauge theories

    Mohamed M. Anber🇬🇧 · Samson Y.L. Chan🇬🇧

    We undertake a systematic study of the $4$-dimensional $SU(N)$ $2$-index chiral gauge theories and investigate their faithful global symmetries and dynamics. These are a finite set of theories with fermions in the $2$-index symmetric and anti-symmetric representations, with no fundamentals, and they do not admit a large-$N$ limit. We employ a combination of perturbative and nonperturbative methods, enabling us to constrain their infrared (IR) phases. Specifically, we leverage the 't Hooft anomalies associated with continuous and discrete groups to eliminate a few scenarios. In some cases, the anomalies rule out the possibility of fermion composites. In other cases, the interplay between the continuous and discrete anomalies leads to multiple higher-order condensates, which inevitably form to match the anomalies. Further, we pinpoint the most probable symmetry-breaking patterns by searching for condensates that match the full set of anomalies resulting in the smallest number of IR degrees of freedom. Higher-loop $\beta$-function analysis suggests that a few theories may flow to a conformal fixed point.

    ↳ hep-thhep-lathep-phJHEP(2023)·11 citations
16. 16*

    Slow diffusion around pulsar $\gamma$-ray halos and its impact on cosmic rays propagation

    Xiao-Jun Bi🇨🇳

    The diffusion coefficients around the pulsar $\gamma$-ray halos are highly suppressed compared with the value in the interstellar medium. It is suggested in the literature that the $\gamma$-ray halos can be explained by a ballistic-diffusive (BD) propagation without slow diffusion. However our calculation shows that the BD propagation can not account for the $\gamma$-ray halo profile well. Furthermore the transfer efficiency of the pulsar spin down energy to the high energy electrons and positrons is even larger than 1 in the BD scenario. Therefore slow diffusion is necessary to account for the pulsar $\gamma$-ray halos. Taking the slow diffusion into account the contribution of positron flux originated from nearby pulsars to the AMS-02 data is reexamined. We may also expect a slow diffusion disk of the Milky Way as many such slow diffusion regions exist. The positron contribution to the AMS-02 data from dark matter annihilation in the new propagation model is also reexamined. We find that the dark matter scenario satisfies all the $\gamma$-ray limits in the new propagation model.

    ↳ astro-ph.HEhep-ph3 citations
17. 17*

    Spontaneous Supersymmetry Breaking in Inhomogeneous Supersymmetric Field Theories and BPS Vacua

    Yoonbai Kim🇰🇷 · O-Kab Kwon🇰🇷 · D. D. Tolla🇰🇷

    We study spontaneous supersymmetry breaking in inhomogeneous extensions of $\mathcal{N}=1$ supersymmetric field theory models in 4-dimensions. The $\mathcal{N}=1$ Abelian Higgs model with the inhomogeneous mass parameter and the FI coefficient that are dependent on spatial coordinates, as well as the O'Raifeartaigh model with all its parameters being dependent on spatial coordinates, are studied in detail. In the presence of inhomogeneous parameters, half supersymmetry can be preserved by adding appropriate inhomogeneous deformations to the original Lagrangians. The inhomogeneous deformations often break the R-symmetry explicitly. In cases where the inhomogeneous deformations do not break the R-symmetry explicitly, we demonstrate that spontaneous breaking of the R-symmetry is infeasible. We argue that those models can not be spontaneous supersymmetry breaking models, according to the Nelson-Seiberg argument. We comment on this issue in the context of a generic $\mathcal{N}=1$ supersymmetric model as well.

    ↳ hep-thhep-phJHEP(2023)·4 citations
18. 18*

    An Eight Loop Amplitude via Antipodal Duality

    Lance J. Dixon🇺🇸 · Yu-Ting Liu🇺🇸

    We compute the six-particle maximally-helicity-violating (MHV) amplitude in planar $\mathcal{N}=4$ super-Yang-Mills theory at eight loops, using antipodal duality and the recently computed eight-loop three-point form factor for the chiral stress energy tensor multiplet. Antipodal duality maps the form factor symbol to the amplitude symbol on a two-dimensional parity-preserving surface in the three-dimensional amplitude kinematics. There are remarkably few ambiguities in lifting from two to three dimensions, nor in promoting the symbol to a function. The amplitude passes many tests, including near-collinear, multi-Regge, factorization, self-crossing and origin limits. These checks also constitute a validation of antipodal duality at eight loops.

    ↳ hep-thhep-phJHEP(2023)·43 citations
19. 19*

    First results of the SUPAX Experiment: Probing Dark Photons

    Tim Schneemann🇩🇪 · Kristof Schmieden🇩🇪 · Matthias Schott🇩🇪

    We show the first results of a new cavity based haloscope searching for dark photons with masses around $34\mu \text{eV}$. Dark photons are hypothetical vector particles and a compelling dark matter candidate. Having the same quantum numbers as photons a kinematic mixing between both is expected, leading to conversions from dark photons to standard model photons, where the photon frequency depends on the dark photon mass. For wavelengths in the microwave regime resonators are typically used to enhance the signal. A new experiment is setup at the University of Mainz. In this paper we present the initial results from the new setup searching for dark photons utilising a 8.3 GHz copper cavity at LHe temperatures. Limits on the kinetic mixing parameter $\chi <(6.20\pm 3.15^{\text{(exp.)}}\pm 9.65^{\text{(SG)}})\cdot 10^{-14}$ at 95\% CL are set at a single frequency as proof of concept. Finally the next steps of the experiment and expected sensitivity are detailed.

    ↳ hep-exastro-ph.COhep-ph15 citations
20. 20*

    Wilson Loop Duality and OPE for Super Form Factors of Half-BPS Operators

    Benjamin Basso🇫🇷 · Alexander G. Tumanov🇫🇷

    We propose a dual Wilson loop description for the MHV super form factors of half-BPS operators in planar $\mathcal{N}=4$ super-Yang-Mills theory. In this description, the local operators are represented by on-shell states, made out of zero-momentum particles, that are absorbed by a null periodic super Wilson loop. We present evidence for this duality at weak coupling, by performing an explicit calculation of the Wilson loop matrix elements through one loop. At tree level, the interactions localize at the cusps of the loop, revealing a simple connection between the super form factors and the $m=2$ tree amplituhedron. At loop level, we show that the Wilson loop calculation reproduces the known results for the super form factors. Inspired by this duality, we extend the OPE program developed for the form factors of the Lagrangian to the super form factors of the higher-charge operators. We introduce non-perturbative axioms and conjectures for the main building blocks that govern the exchange of the lightest flux-tube excitations. These blocks appear as simple refinements of the form factor transitions introduced in earlier OPE studies. They are expressed at any value of the 't Hooft coupling in terms of the tilted Beisert-Eden-Staudacher kernel. We carry out checks of our conjectures up to two loops at weak coupling for three- and four-point form factors of half-BPS operators of various lengths, finding perfect agreement with perturbative data.

    ↳ hep-thhep-phJHEP(2024)·19 citations
21. 21*

    Gravitational Wave Emission from a Cosmic String Loop, I: Global Case

    Jorge Baeza-Ballesteros🇪🇸 · Edmund J. Copeland🇬🇧 · Daniel G. Figueroa🇪🇸 · Joanes Lizarraga🇪🇸

    We study the simultaneous decay of global string loops into scalar particles (massless and massive modes) and gravitational waves (GWs). Using field theory simulations in flat space-time of isolated loops with initial length $\sim 80-1700$ times their core width, we determine the power emitted into scalar particles, $P_{\phi }$, and GWs, $P_{\mathrm{GW}}$, and characterize the loop decay timescale as a function of its initial length, energy and angular momentum. We quantify infrared and ultraviolet lattice dependencies of our results. For all type of loops and initial conditions considered, GW emission is always suppressed compared to particles as $P_{\mathrm{GW}}/P_{\phi }\approx \mathcal{O}(10)(v/m_{\text{p}}{)}^2\ll 1$, where $v$ is the vacuum expectation value associated with string formation. These conclusions are robust for the length-to-width ratios considered, with no indication they should change if the ratio is increased. The results suggest that the GW background from a global string network, such as in dark matter axion scenarios, will be suppressed compared to previous expectations.

    ↳ astro-ph.COhep-phPRD(2024)·45 citations
22. 22*

    Dark sector and Axion-like particle search at BESIII

    Vindhyawasini Prasad (On behalf of the BESIII Collaboration)🇨🇱

    Dark matter (DM) refers to a new type of matter that may explain observed rotation curves of galaxies and the composite structure of the Universe. It may couple to the Standard Model particles via portals, which include the possibility of axion-like particle, light Higgs boson, dark photon and spin-1/2 fermions. The axion-like particle and light Higgs boson can be accessible via radiative decays of $J/\psi$ while the dark photon via initial-state radiation process using the data of high-intensity $e^{+}{e}^{-}$ collider experiments, such as the BESIII experiment. DM may be depicted as baryonic matter in an invisible final state. The presence of a massless dark photon, predicted by the spontaneous broken of Abelian group $U(1{)}_D$, may enhance the branching fractions of rare flavor changing neutral current decay processes. BESIII experiment has recently explored the possibility of these DM scenarios using the data samples collected at several energy points, including $J/\psi$ and $\psi (3686)$ resonances. This report summarizes the recent results of the BESIII experiment related to the dark-sector and Axion-like particles.

    ↳ hep-exhep-phhttps://zenodo.org/record/8429648 (2023)·1 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.