Tue·Aug 1, 2023Tuesday·August 1, 2023

1. 01*

   Light Neutrinophilic Dark Matter from a Scotogenic Model

   Johannes Herms🇩🇪 · Sudip Jana🇩🇪 · Vishnu P.K. · Shaikh Saad🇨🇭

   We present a minimal sub-GeV thermal Dark Matter (DM) model where the DM primarily interacts with neutrinos and participates in neutrino mass generation through quantum loop corrections at one-loop level. We discuss the challenges in achieving this in the scotogenic framework and identify a viable variant. Due to minimality and the interplay between obtaining the correct DM relic abundance and neutrino oscillation data, the model predicts (i) a massless lightest neutrino, (ii) enhanced rate of $0\nu \beta \beta$ decay due to loop corrections involving light DM exchange, and (iii) testable lepton flavor-violating signal $\mu \to e\gamma$. Detecting monoenergetic neutrinos from DM annihilation in next-generation neutrino detectors offers a promising way to test this scenario.

   hep-phhep-exPLB(2023)·16 citations
2. 02*

   Old Ideas for New Physicists 2

   T. Banks🇺🇸

   We review ideas relating the breaking of Supersymmetry in de Sitter (dS) space-time to amplitudes in which gravitinos are reflected from the dS horizon. A self consistent evaluation of such amplitudes leads to the estimate $m_{3/2}=K{\Lambda }^{1/4}$, with a constant $K$ that is not easily calculable. LHC bounds on superpartner masses, plus the structure of low energy effective field theory then imply that there must be new superfields with standard model quantum numbers in the region below $100$ TeV. Only one class of models, the Pyramid Schemes, has been found, which is compatible with one loop coupling unification. They have a new strongly coupled gauge sector with a confinement scale in the multi TeV region. We outline the general predictions of these models, which include Dirac gauginos and a novel solution of the strong CP problem. The models all appear to have a "little hierarchy problem": the expectation value of the standard model Higgs field, and its mass, must be a factor of $10$ or more smaller than the masses of the second Higgs doublet or standard model superpartners. Since all of these models contain uncertainties from the strong coupling physics, as well as the physics of the dS horizon, it is difficult to determine how serious this fine tuning problem is.

   hep-phhep-th4 citations
3. 03*

   Light-Quark $SU(3)$ Flavour Splitting of Heavy-Light Constituent Diquark Masses and Doubly-Strange Diquarks from QCD Sum-Rules

   T. de Oliveira🇨🇦 · D. Harnett🇨🇦 · R. Kleiv🇨🇦 · A. Palameta🇨🇦 · T.G. Steele🇨🇦

   QCD Laplace sum-rules are used to examine the constituent mass spectrum of $J^P\in \{0^{+},1^{+}\}$ heavy-light [Qq] diquarks with $Q\in \{c,b\}$ and $q\in \{u,d,s\}$. As in previous sum-rule studies, the negative parity $J^P\in \{0^{-},1^{-}\}$ [Qq] diquark mass predictions do not stabilize, so the sum-rule analysis focuses on positive parity [Qq] diquarks. Doubly-strange $J^P=1^{+}$ [ss] diquarks are also examined, but the resulting sum rules do not stabilize. Hence there is no sum-rule evidence for $J^P=1^{+}$ [ss] diquark states, aiding the interpretation of sum-rule analyses of fully-strange tetraquark states. The SU(3) flavour splitting effects for [Qq] diquarks are obtained by calculating QCD correlation functions of $J^P\in \{0^{+},1^{+}\}$ diquark composite operators up to next-to-leading order in perturbation theory, leading-order in the strange quark mass, and in the chiral limit for non-strange (u,d) quarks with an isospin-symmetric vacuum $<\bar{n}n>=<\bar{u}u>=<\bar{d}d>$. Apart from the strange quark mass parameter $m_s$, the strange quark condensate parameter $\kappa =<\bar{s}s>/<\bar{n}n>$ has an important impact on SU(3) flavour splittings. A Laplace sum-rule analysis methodology is developed for the mass difference $M_{[Qs]}-M_{[Qn]}$ between the strange and non-strange heavy-light diquarks to reduce the theoretical uncertainties from all other QCD input parameters. The mass splitting is found to decrease with increasing $\kappa$, providing an upper bound on $\kappa$ where the $M_{[Qs]}-M_{[Qn]}$ mass hierarchy reverses. In the typical QCD sum-rule range $0.56<\kappa <0.74$, $55MeV<M_{[cs]}-M_{[cn]}<100MeV$ and $75MeV<M_{[bs]}-M_{[bn]}<150MeV$, with a slight tendency for larger splittings for the $J^P=1^{+}$ channels. These constituent mass splitting results are discussed in comparison with values used in constituent diquark models for tetraquark and pentaquark hadronic states.

   hep-phPRD(2023)·9 citations
4. 04*

   Alternative 3-3-1 models with exotic electric charges

   Eduard Suarez🇨🇴 · Richard H. Benavides🇨🇴 · Yithsbey Giraldo🇨🇴 · William A. Ponce🇨🇴 · Eduardo Rojas🇨🇴

   We report the most general classification of 3-3-1 models with $\beta =\sqrt{3}$. We found several solutions where anomaly cancellation occurs among fermions of different families. These solutions are particularly interesting as they generate non-universal heavy neutral vector bosons. Non-universality in the SM fermion charges under an additional gauge group generates Charged Lepton Flavor Violation (CLFV) and Flavor Changing Neutral Currents~(FCNC); we discuss under what conditions the new models can evade constraints coming from these processes. In Addition, we also report LHC constraints.

   hep-phJ.Phys.G(2024)·4 citations
5. 05*

   Correlator webs of massive multiparton amplitudes at four loops: A study of boomerang webs

   Neelima Agarwal · Sourav Pal🇮🇳 · Aditya Srivastav🇮🇳 · Anurag Tripathi🇮🇳

   Logarithm of the soft function can be organized into sets of Feynman diagrams known as Cwebs. We introduced a new formalism in~\cite{Agarwal:2022wyk}, that allows to determine several of the building blocks of Cweb mixing matrices without explicit computations. In~\cite{Agarwal:2022xec} we used this formalism to obtain the diagonal blocks of four general classes of Cwebs to all orders in perturbation theory which also covered all the four loop Boomerang Cwebs connecting four Wilson lines. In this work we present complete mixing matrices and exponentiated colour factors for Boomerang Cwebs at four loops that connect three and four Wilson lines. Also, we present a more efficient version of the algorithm of generating Cwebs that was presented in~\cite{Agarwal:2020nyc}. This new algorithm has been used to generate the Cwebs in the present work.

   hep-phhep-thPRD(2024)·4 citations
6. 06*

   A short overview on low mass scalars at future lepton colliders -- LCWS23 proceedings

   Tania Robens🇭🇷

   I give a short summary on scenarios with new physics scalars that could be investigated at future $e^{+}{e}^{-}$ colliders. I concentrate on cases where at least one of the additional scalar has a mass below 125 GeV, and discuss both models where this could be realized, as well as studies which focus on such scenarios. This work is based on arXiv:2205.09687, and partial results were also presented in arXiv:2211.10231.

   hep-ph3 citations
7. 07*

   Quantum Electrodynamic Corrections to Cyclotron States in a Penning Trap

   Ulrich D. Jentschura🇺🇸 · Christopher Moore🇺🇸

   We analyze the leading and higher-order quantum electrodynamic corrections to the energy levels for a single electron bound in a Penning trap, including the Bethe logarithm correction due to virtual excitations of the reference quantum cyclotron state. The effective coupling parameter alpha_c in the Penning trap is identified as the square root of the ratio of the cyclotron frequency, converted to an energy via multiplication by the Planck constant, to the electron rest mass energy. We find a large, state-independent, logarithmic one-loop self-energy correction of order alpha alpha_c^4 m c^2 ln(alpha_c^(-2)), where m is the electron rest mass and c is the speed of light. Furthermore, we find a state-independent "trapped" Bethe logarithm. We also obtain a state-dependent higher-order logarithmic self-energy correction of order alpha alpha_c^6 m c^2 ln(alpha_c^(-2)). In the high-energy part of the bound-state self energy, we need to consider terms with up to six magnetic interaction vertices inside the virtual photon loop.

   hep-phPRD(2023)·5 citations
8. 08*

   QCD corrections to the Golden decay channel of the Higgs boson

   Mandeep Kaur🇮🇳 · Maguni Mahakhud🇮🇳 · Ambresh Shivaji🇮🇳 · Xiaoran Zhao🇮🇹

   Future colliders aim to provide highly precise experimental measurements of the properties of the Higgs boson. In order to benefit from these precision machines, theoretical errors in the Higgs sector observables have to match at least the experimental uncertainties. The theoretical uncertainties in the Higgs sector observables can be reduced by including missing higher-order terms in their perturbative calculations. In this direction, we compute the mixed QCD-electroweak corrections at $\mathcal{O}(\alpha {\alpha }_s)$ to the Higgs decay into four charged leptons by considering the golden decay channel, $H\to e^{+}{e}^{-}{\mu }^{+}{\mu }^{-}$. Due to color conservation, these corrections receive contributions only from the two-loop virtual diagrams. In the complex mass scheme, we find that the mixed QCD-electroweak corrections to the partial decay width, relative to the leading order predictions, are positive and about $0.27\%$ for ${\alpha }_s(M_Z)$. Relative to the next-to-leading order electroweak corrections, the mixed QCD-electroweak corrections are found to be approximately $18\%$ for ${\alpha }_s(M_Z)$. With respect to the leading order, we observe a flat effect of the mixed QCD-electroweak corrections on the invariant mass distribution of the lepton pairs with fixed QCD coupling. The $\varphi$ distribution, due to the mixed QCD-electroweak corrections, follows a $(1-\cos \varphi )$ dependence.

   hep-phhep-exhep-thJHEP(2024)·4 citations
9. 09*

   Doubly-charged scalars of the Minimal Left-Right Symmetric Model at Muon Colliders

   Mohamed Belfkir🇦🇪 · Talal Ahmed Chowdhury🇧🇩 · Salah Nasri🇦🇪

   We investigate the prospects of probing the doubly-charged scalars of the minimal Left-Right Symmetric model (MLRSM) at a muon collider. We assess its capability by studying the production of doubly-charged scalars and their subsequent decay into four charged lepton final states containing the same-charge lepton pairs. We find that the channels with same-charge electron and muon pairs, i.e., ($e^{\pm }{e}^{\pm }{\mu }^{\mp }{\mu }^{\mp }$ and its charge conjugated pairs), have the largest sensitivity due to the lowest Standard Model background. Besides, we show that the possibility of using fully polarized initial muon beams in the muon collider can enhance the detection sensitivity of doubly-charged scalars of the MLRSM. Furthermore, we show that one can put exclusion limits on the magnitudes of triplet Yukawa couplings that are directly related to the neutrino sector of the MLRSM for the mass range $1.1-5$ TeV of the doubly-charged scalars.

   hep-phhep-exPLB(2024)·20 citations
10. 10*

    Electromagnetic and hadronic decay of fully heavy tetraquark

    Wen-Long Sang (SWU)🇨🇳 · Tao Wang (SWU)🇨🇳 · Yu-Dong Zhang (CCNU)🇨🇳 · Feng Feng (CUMT)🇨🇳

    In this study, we compute the electromagnetic and hadronic decay widths of the S-wave fully heavy tetraquark $T_{4Q}$ ($Q=c$ or $b$) at lowest order in ${\alpha }_s$ and $v$, in the framework of nonrelativistic QCD. The short-distance coefficients are determined through the standard procedure of matching. The nonperturbative long-distance matrix elements are related to the phenomenological four-body Schrödinger wave functions at the origin, whose values are taken from literature. The branching fractions are predicted to be around $10^{-4}$ and $10^{-7}-10^{-6}$ for the $T_{4c}$ hadronic decay and electromagnetic decay, respectively. Combing our results with the $T_{4c}$ production cross sections at the LHC, we also predict the event numbers for various decay channels. With integrated luminosity $\mathcal{L}=100{\mathrm{fb}}^{-1}$, it is expected that the event numbers can reach $10^3$ for $T_{4c}\to \gamma \gamma$, and $10^6$ for $T_{4c}\to \mathrm{LH}$, at the LHC. The detecting prospect is promising. In addition, the decay widths of $T_{4b}$ are estimated based on simple dimensional analysis as well as velocity scaling rule.

    hep-phhep-exPRD(2024)·23 citations
11. 11*

    Bjorken sum rule with analytic coupling at low Q2 values

    I.R. Gabdrakhmanov🇷🇺 · N.A Gramotkov🇷🇺 · A.V. Kotikov🇷🇺 · D.A. Volkova🇷🇺 · I.A. Zemlyakov🇷🇺

    The experimental data obtained for the polarized Bjorken sum rule \Gamma^{(p-n)}_1(Q^2) for small values of Q2 are approximated by the predictions obtained in the framework of analytic QCD up to the 5th order perturbation theory, whose coupling constant does not contain the Landau pole. We found an excellent agreement between the experimental data and the predictions of analytic QCD, as well as a strong difference between these data and the results obtained in the framework of standard QCD.

    hep-phPisma Zh.Eksp.Teor.Fiz.(2023)·16 citations
12. 12*

    On ultrahigh-energy neutrino-nucleon deep-inelastic scattering and the Froissart bound

    A.V. Kotikov🇷🇺 · I.A. Kotikov🇷🇺

    A brief review of the results for the total cross section \sigma^{\nu N} of ultrahigh-energy neutrino deep inelastic scattering on isoscalar nuclear targets is presented. These results are based on simple approximations for \sigma^{\nu N} and are compared with the experimental data of the IceCube Collaboration. The total cross section \sigma^{\nu N} is proportional to the structure function F_2^{\nu N}(M_V^2/s,M_V^2), where M_V is the intermediate boson mass and s is square of the energy of the center of mass. The coefficient in the front of F_2^{\nu N}(M_V^2/s,M_V^2) depends on the asymptotic behavior of F_2^{\nu N} at low values of x. It contains an additional term \sim \ln{s} if F_2^{\nu N} is scaled by the power \ln(1/x). Therefore, the asymptotic behavior of F_2^{\nu N}\propto\ln^2(1/x) for small x often assumed in the literature already leads to violation of the Froissart bound for \sigma^{\nu N}.

    hep-phPhys.Atom.Nucl.(2023)·0 citations
13. 13*

    Bremsstrahlung Cross Section with Polarized Beams for Luminosity Determination at the EIC

    Dhevan Gangadharan🇺🇸

    The bremsstrahlung cross section is calculated at leading order for polarized beams of electrons and ions, which is needed for luminosity measurements at the upcoming Electron Ion Collider (EIC). Analytic expressions, differential in the emitted photon energy and polar angle, are derived. The component of the cross section which depends on the beam polarizations is found to be highly suppressed with respect to the unpolarized Bethe-Heitler component, owing to the low $q^2$ that characterizes the bremsstrahlung process.

    hep-phhep-exnucl-exnucl-thEPJA(2023)·1 citation
14. 14*

    Classical vs. quantum corrections to jet broadening in a weakly coupled QGP

    Eamonn Weitz🇫🇷

    We compute double-logarithmically enhanced corrections to $\hat{q}$ at relative order $O(g^2)$ in the setting of a weakly coupled quark-gluon plasma, observing how the thermal scale affects the region of phase space, which gives rise to these corrections. We furthermore clarify how the region of phase from which these corrections are borne is situated with respect to that from which the classical corrections arise at relative order $O(g)$. This represents a significant step towards our eventual goal of understanding which class of corrections dominate, thereby pushing forward our quantitative grasp on the phenomenon of jet quenching in heavy-ion collisions.

    hep-phnucl-thPoS(2024)·0 citations
15. 15*

    Higher strangeonium decays into light flavor baryon pairs like $\Lambda \bar{\Lambda }$, $\Sigma \bar{\Sigma }$, and $\Xi \bar{\Xi }$

    Zi-Yue Bai🇨🇳 · Qin-Song Zhou🇨🇳 · Xiang Liu🇨🇳

    In this work, we investigate the decay behaviors of several higher strangeonia into $\Lambda \bar{\Lambda }$ through a hadronic loop mechanism, enabling us to predict some physical observables, including the branching ratios. Furthermore, we assess the reliability of our research by successfully reproducing experimental data related to the cross section of $e^{+}{e}^{-}\to \Lambda \bar{\Lambda }$ interactions. In this context, we account for the contributions arising from higher strangeonia, specifically $\varphi (4S)$ and $\varphi (3D)$. Additionally, we extend this study to encompass higher strangeonia decays into other light flavor baryon pairs, such as $\Sigma \bar{\Sigma }$ and $\Xi \bar{\Xi }$. By employing the same mechanism, we aim to gain valuable insights into the decay processes involving these particles. By conducting this investigation, we hope to shed light on the intricate decay mechanisms of higher strangeonia and their interactions with various baryons pairs.

    hep-phhep-exPRD(2023)·11 citations
16. 16*

    Ground states of all mesons and baryons in a quark model with Hidden Local Symmetry

    Bing-Ran He🇨🇳 · Masayasu Harada🇯🇵 · Bing-Song Zou🇨🇳

    We extend the chiral quark model for $u$, $d$, $c$ and $b$ quarks with vector mesons, which we proposed in the previous analysis, to a model with the $s$ quark. We include the nonet pseudo-scalar and vector mesons together with the singlet scalar meson based on the SU(3)${}_L\times$SU(3)${}_R$ chiral symmetry combined with the Hidden Local Symmetry, which mediate force among $u$, $d$ and $s$ quarks. We fit the model parameters to the known ground state mesons and baryons. We show that the mass spectra of those hadrons are beautifully reproduced. We predict the masses of missing ground states, one meson and twenty baryons, which will be tested in the future experiment.

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

    Cosmic Birefringence as a probe of dark matter nature: Sterile neutrino and dipolar dark matter

    Jafar Khodagholizadeh🇮🇷 · S. Mahmoudi🇮🇷 · R. Mohammadi🇮🇷 · M. Sadegh🇮🇷

    Recently, non-zero rotation angle $\beta =0.30^{\circ }\pm 0.11^{\circ }$ $(68\%\text{ C.L.})$ [Phys. Rev. Lett. \textbf{128}, no.9, 091302 (2022)] has been reported for linear polarization of cosmic microwave background (CMB) radiation, which is known as cosmic birefringence (CB). We used this birefringence angle of CMB to study and distinguish different candidates of dark matter (DM), e.g., dipolar and sterile neutrino DM. We calculated CMB forward scattering by those probable candidates of DM to generate $\beta$ in the presence of primordial scalar fluctuations' background. We explicitly plotted bounds on the mass and electromagnetic coupling for different sectors of DM, sterile neutrino, and dipolar DM, and compared them with other experimental bounds. Regarding dipolar DM, our calculations put a bound on the Majorana magnetic dipole moment about $\mathcal{M}⩽1.4\times 10^{-14}\frac{\beta }{0.30^{\circ }}\sqrt{\frac{m_{\text{DM}}}{1GeV}}e.\text{cm}$. In the case of sterile neutrino DM, the bound on the mass and mixing angle was estimated at ${\theta }^2⩽3.3(rad{)}^2\frac{\beta }{0.30^{\circ }}\frac{m_{DM}}{\mathrm{KeV}}$, which can be a new constraint for sterile neutrino DM whose production mechanism is motivated by models with a hidden sector coupled to the sterile neutrino. Based on our results, if the constraint on the mass and the electromagnetic coupling for DM must be within the allowed region, none of the considered candidates can compensate for all the observed CB angles. We also discussed the maximum contribution of the CB angle via CMB forward scattering by different sectors of the dark matter.

    hep-phgr-qcPRD(2023)·6 citations
18. 18*

    Hadronic structure on the light-front VIII. Light scalar and vector mesons

    Wei-Yang Liu🇺🇸 · Edward Shuryak🇺🇸 · Ismail Zahed🇺🇸

    We use the QCD instanton vacuum model to discuss the emergence of the light scalar and vector mesons on the light front. We take into account both the instanton and anti-instanton single and molecular interactions on the light quarks, in the form of non-local effective interactions. Although the molecular induced interactions are suppressed by a power of the packing fraction, they are still sufficient to bind the vector mesons, while keeping most of the scalar spectrum relatively unchanged. We explicitly derive the light front distribution amplitudes (DAs) and partonic functions (PDFs) for the scalar and vector mesons, and compare them after pertinent QCD evolution, to the available empirical and lattice measured counterparts. The Dirac electric form factors for both the pion and rho meson are derived, and shown to compare well with current data.

    hep-phnucl-thPRD(2024)·19 citations
19. 19*

    Cascade of polarized Compton scattering and Breit-Wheeler pair production

    Qian Zhao🇨🇳 · Ting Sun🇨🇳 · Kun Xue🇨🇳 · Feng Wan🇨🇳 · Jian-Xing Li🇨🇳

    Cascaded Compton scattering and Breit-Wheeler (BW) processes play fundamental roles in high-energy astrophysical sources and laser-driven quantum electrodynamics (QED) plasmas. A thorough comprehension of the polarization transfer in these cascaded processes is essential for elucidating the polarization mechanism of high-energy cosmic gamma rays and laser-driven QED plasmas. In this study, we employ analytical cross-sectional calculations and Monte Carlo (MC) numerical simulations to investigate the polarization transfer in the cascade of electron-seeded inverse Compton scattering (ICS) and BW process. Theoretical analysis indicates that the polarization of background photons can effectively transfer to final-state particles in the first-generation cascade due to helicity transfer. Through MC simulations involving polarized background photons and non-polarized seed electrons, we reveal the characteristic polarization curves as a function of particle energy produced by the cascaded processes of ICS and BW pair production. Our results demonstrate that the first-generation photons from ICS exhibit the non-decayed stair-shape polarization curves, in contrast to the linearly decayed ones of the first-generation electrons. Interestingly, this polarization curve trend can be reversed in the second-generation cascade, facilitated by the presence of polarized first-generation BW pairs with fluctuant polarization curves. The cascade culminates with the production of second-generation BW pairs, due to diminished energy of second-generation photons below the threshold of BW process. Our findings provide crucial insights into the cascaded processes of Compton scattering and BW process, significantly contributing to the understanding and further exploration of laser-driven QED plasma creation in laboratory settings and high-energy astrophysics research.

    hep-phPRD(2023)·5 citations
20. 20*

    Investigation on the higher twist TMD $h_3$ for proton in the light-front quark-diquark model

    Shubham Sharma🇮🇳 · Harleen Dahiya🇮🇳

    The higher twist T-even transverse momentum dependent distribution (TMD) $h_3(x,{\mathbf{p}}_{\perp }^2)$ for the proton has been examined in the light-front quark-diquark model (LFQDM). By deciphering the unintegrated quark-quark correlator for semi-inclusive deep inelastic scattering (SIDIS), we have derived explicit equations of the TMD for both the scenarios when the diquark is a scalar or a vector. Average as well as average square transverse momenta have been computed for this TMD. Additionally, we have discussed its transverse momentum dependent parton distribution function (TMDPDF) $h_3(x)$.

    hep-phSpringer Proc.Phys.(2024)·0 citations
21. 21*

    Predictions of $m_{ee}$ and neutrino mass from a consistent Froggatt-Nielsen model

    Yu-Cheng Qiu🇨🇳 · Jin-Wei Wang🇨🇳 · Tsutomu T. Yanagida🇨🇳

    The seesaw mechanism is the most attractive mechanism to explain the small neutrino masses, which predicts the neutrinoless double beta decay ($0\nu \beta \beta$) of the nucleus. Thus the discovery of $0\nu \beta \beta$ is extremely important for future particle physics. However, the present data on the neutrino oscillation is not sufficient to predict the value of $m_{ee}$ as well as the neutrino mass $m_{\nu }^i$. In this short article, by adopting a simple and consistent Froggatt-Nielsen model, which can well explain the observed masses and mixing angles of quark and lepton sectors, we calculate the distribution of $m_{ee}$ and $m_{\nu }^i$. Interestingly, a relatively large part of the preferred parameter space can be detected in the near future.

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

    R-parity Conserving Minimal SUSY U(1)${}_X$ Model

    Satsuki Oda🇯🇵 · Nobuchika Okada🇺🇸 · Nathan Papapietro🇺🇸 · Dai-suke Takahashi🇯🇵

    We propose a minimal gauged U(1)${}_X$ extension of the MSSM with R-parity conservation. In this model, U(1)${}_X$ is a generalization of the well-known U(1) $B-L$. Apart from the MSSM particle content, the model includes three right-handed neutrino (RHN) chiral superfields, each carrying a unit U(1)${}_X$ charge. In the presence of RHNs, the model is free from all gauge and mixed gauge-gravitational anomalies. However, there are no U(1)${}_X$ Higgs chiral superfields with U(1)${}_X$ charge $\pm 2$ involved in the model. Two of the RHN superfields are assigned an odd R-parity, while the last one ($\Psi$) has an even parity. The U(1)${}_X$ symmetry is radiatively broken by the VEV of the scalar component of $\Psi$. As a consequence of the absence of U(1)${}_X$ Higgs fields and the novel R-parity assignment, the three light neutrinos consist of one massless neutrino and two Dirac neutrinos. In the early universe, the right-handed components of the Dirac neutrinos are in thermal equilibrium with the SM particles through the U(1)${}_X$ gauge ($Z^{\prime }$) boson. The extra energy density from the RHNs is constrained to avoid disrupting the success of BBN, leading to a lower bound on the scale of U(1)${}_X$ symmetry breaking. In our model, a mixture of the U(1)${}_X$ gaugino and the fermionic component of $\Psi$ becomes a new dark matter (DM) candidate if it is the lightest sparticle mass eigenstate. We examine this DM phenomenology and identify a parameter region that reproduces the observed DM relic density. Furthermore, we consider constraints from the search for $Z^{\prime }$ boson resonance at the LHC. The three constraints obtained from the success of BBN, the observed DM relic density, and the $Z^{\prime }$ resonance search at the LHC complement each other, narrowing down the allowed parameter region.

    hep-phastro-ph.COhep-ex0 citations
23. 23*

    Rapidity gap distribution of diffractive small-$x_{IP}$ events at HERA and at the EIC

    Tuomas Lappi (1 and 2)🇫🇮 · Anh Dung Le (1 and 2)🇫🇮 · Heikki Mäntysaari (1 and 2) ((1) Department of Physics, University of Jyväskylä, (2) Helsinki Institute of Physics)🇫🇮

    We use the Kovchegov-Levin equation to resum contributions of large invariant mass diffractive final states to diffractive structure functions in the dipole picture of deep inelastic scattering. For protons we use a (modified) McLerran-Venugopalan model as the initial condition for the evolution, with free parameters obtained from fits to the HERA inclusive data. We obtain an adequate agreement to the HERA diffractive data in the moderately high-mass regimes when the proton density profile is fitted to the diffractive structure function data in the low-mass region. The HERA data is found to prefer a proton shape that is steeper than a Gaussian. The initial conditions are generalized to the nuclear case using the optical Glauber model. Strong nuclear modification effects are predicted in diffractive scattering off a nuclear target in kinematics accessible at the future Electron-Ion collider. In particular, the Kovchegov-Levin evolution has a strong effect on the Q 2 -dependence of the diffractive cross section.

    hep-phPRD(2023)·18 citations
24. 24*

    Explainable Equivariant Neural Networks for Particle Physics: PELICAN

    Alexander Bogatskiy🇺🇸 · Timothy Hoffman🇺🇸 · David W. Miller🇺🇸 · Jan T. Offermann🇺🇸 · Xiaoyang Liu🇺🇸

    PELICAN is a novel permutation equivariant and Lorentz invariant or covariant aggregator network designed to overcome common limitations found in architectures applied to particle physics problems. Compared to many approaches that use non-specialized architectures that neglect underlying physics principles and require very large numbers of parameters, PELICAN employs a fundamentally symmetry group-based architecture that demonstrates benefits in terms of reduced complexity, increased interpretability, and raw performance. We present a comprehensive study of the PELICAN algorithm architecture in the context of both tagging (classification) and reconstructing (regression) Lorentz-boosted top quarks, including the difficult task of specifically identifying and measuring the $W$-boson inside the dense environment of the Lorentz-boosted top-quark hadronic final state. We also extend the application of PELICAN to the tasks of identifying quark-initiated vs.~gluon-initiated jets, and a multi-class identification across five separate target categories of jets. When tested on the standard task of Lorentz-boosted top-quark tagging, PELICAN outperforms existing competitors with much lower model complexity and high sample efficiency. On the less common and more complex task of 4-momentum regression, PELICAN also outperforms hand-crafted, non-machine learning algorithms. We discuss the implications of symmetry-restricted architectures for the wider field of machine learning for physics.

    hep-phcs.LGhep-exJHEP(2024)·61 citations
25. 25*

    Measurement of the CPV Higgs mixing angle in ZZ-fusion at 1 TeV ILC

    N. Vukašinović🇷🇸 · I. Božović-Jelisavčić🇷🇸 · G. Kačarević🇷🇸

    Although the studies of tensor structure of the Higgs boson interactions with vector bosons and fermions at CMS and ATLAS experiments have established that the $J^{\mathrm{PC}}$ quantum numbers of the Higgs boson should be $0^{++}$, small CP violation in the Higgs sector (up to 10% contribution of the CP-odd state) cannot be excluded with the current experimental precision. We review possibilities to measure CP violating mixing angle ${\Psi }_{\mathrm{CP}}$ between scalar and pseudoscalar states, at a linear electron-positron collider, at center-of-mass energy of 1 TeV.

    hep-ph0 citations
26. 26*

    Higgs self-coupling measurement at the International Linear Collider

    Julie Munch Torndal🇩🇪 · Jenny List🇩🇪

    The Higgs sector of particle physics is still largely uncovered, where establishing the Higgs mechanism is central to advance the field. The Higgs self-coupling is the key ingredient missing and an important puzzle piece for potentially uncovering new physics beyond the standard model. With the energy reach and precision reach of linear $e^{+}{e}^{-}$ colliders, the Higgs self-coupling can be measured directly and precisely enough that certain BSM scenarios can be evaluated. A new analysis of the capability to measure the Higgs self-coupling at the International Linear Collider (ILC) is ongoing and have identified aspects concerning the reconstruction tools which are expected to improve precision reach and are presented. This ongoing analysis intends to update the state-of-the-art projections for measuring the Higgs self-coupling at ILC which was previously evaluated at a centre-of-mass energy of 500 GeV. Additionally, the ongoing analysis intends to evaluate the choice of centre-of-mass energy and how it influences the reachable precision, as well as to consider how BSM effects might influence the reachable precision.

    hep-phhep-ex8 citations
27. 27*

    Quantum local-equilibrium state with fixed multiplicity constraint and Bose-Einstein momentum correlations

    M.D. Adzhymambetov🇺🇦 · S.V. Akkelin🇺🇦 · Yu.M. Sinyukov🇺🇦

    The one- and two-boson momentum spectra are derived in the quantum local-equilibrium canonical ensemble of noninteracting bosons with a fixed particle number constraint. We define the canonical ensemble as a subensemble of events associated with the grand-canonical ensemble. Applying simple hydro-inspired parametrization with parameter values that correspond roughly to the values at the system's breakup in $p+p$ collisions at the LHC energies, we compare our findings with the treatment which is based on the grand-canonical ensembles where mean particle numbers coincide with fixed particle numbers in the canonical ensembles. We observe a significantly greater sensitivity of the two-particle momentum correlation functions to fixed multiplicity constraint compared to one-particle momentum spectra. The results of our analysis may be useful for interpretation of multiplicity-dependent measurements of $p+p$ collision events.

    hep-phhep-exnucl-exnucl-thPRD(2023)·3 citations
28. 28*

    Equilibration of quantum many-body fast neutrino flavor oscillations

    Joshua D. Martin🇺🇸 · Duff Neill🇺🇸 · A. Roggero🇮🇹 · Huaiyu Duan🇺🇸 · J. Carlson🇺🇸

    Neutrino gases are expected to form in high density astrophysical environments, and accurately modeling their flavor evolution is critical to understanding such environments. In this work we study a simplified model of such a dense neutrino gas in the regime for which neutrino-neutrino coherent forward scattering is the dominant mechanism contributing to the flavor evolution. We show evidence that the generic potential induced by this effect is non-integrable and that the statistics of its energy level spaces are in good agreement with the Wigner surmise. We also find that individual neutrinos rapidly entangle with all of the others present which results in an equilibration of the flavor content of individual neutrinos. We show that the average neutrino flavor content can be predicted utilizing a thermodynamic partition function. A random phase approximation to the evolution gives a simple picture of this equilibration. In the case of neutrinos and antineutrinos, processes like ${\nu }_e{\bar{\nu }}_e\leftrightarrows {\nu }_{\mu }{\bar{\nu }}_{\mu }$ yield a rapid equilibrium satisfying $n({\nu }_e)n({\bar{\nu }}_e)=n({\nu }_{\mu })n({\bar{\nu }}_{\mu })=n({\nu }_{\tau })n({\bar{\nu }}_{\tau })$ in addition to the standard lepton number conservation in regimes where off-diagonal vacuum oscillations are small compared to $\nu -\nu$ interactions.

    hep-phnucl-thPRD(2023)·49 citations
29. 29*

    Impact of NNLO QED corrections on lepton-proton scattering at MUSE

    T. Engel🇩🇪 · F. Hagelstein🇨🇭 · M. Rocco🇨🇭 · V. Sharkovska🇨🇭 · A. Signer🇨🇭 · Y. Ulrich🇬🇧

    We present the complete next-to-next-to-leading order (NNLO) pure pointlike QED corrections to lepton-proton scattering, including three-photon-exchange contributions, and investigate their impact in the case of the MUSE experiment. These corrections are computed with no approximation regarding the energy of the emitted photons and taking into account lepton-mass effects. We contrast the NNLO QED corrections to known next-to-leading order corrections, where we include the elastic two-photon exchange (TPE) through a simple hadronic model calculation with a dipole ansatz for the proton electromagnetic form factors. We show that, in the low-momentum-transfer region accessed by the MUSE experiment, the improvement due to more sophisticated treatments of the TPE, including inelastic TPE, is of similar if not smaller size than some of the NNLO QED corrections. Hence, the latter have to be included in a precision determination of the low-energy proton structure from scattering data, in particular for electron-proton scattering. For muon-proton scattering, the NNLO QED corrections are considerably smaller.

    hep-phnucl-exnucl-thEPJA(2023)·15 citations
30. 30*

    Jet Bundle Geometry of Scalar Field Theories

    Mohammad Alminawi🇨🇭 · Ilaria Brivio🇨🇭 · Joe Davighi🇨🇭

    For scalar field theories, such as those EFTs describing the Higgs, it is well-known that the 2-derivative Lagrangian is captured by geometry. That is, the set of operators with exactly 2 derivatives can be obtained by pulling back a metric from a field space manifold $M$ to spacetime $\Sigma$. We here generalise this geometric understanding of scalar field theories to higher- (and lower-) derivative Lagrangians. We show how the entire EFT Lagrangian with up to 4-derivatives can be obtained from geometry by pulling back a metric to $\Sigma$ from the 1-jet bundle that is (roughly) associated with maps from $\Sigma$ to $M$. More precisely, our starting point is to trade the field space $M$ for a fibre bundle $\pi :E\to \Sigma$, with fibre $M$, of which the scalar field $\varphi$ is a local section. We discuss symmetries and field redefinitions in this bundle formalism, before showing how everything can be `prolongated' to the 1-jet bundle $J^{1}E$ which, as a manifold, is the space of sections $\varphi$ that agree in their zeroth and first derivatives above each spacetime point. Equipped with a notion of (spacetime and internal) symmetry on $J^{1}E$, the idea is that one can write down the most general metric on $J^{1}E$ consistent with symmetries, in the spirit of the effective field theorist, and pull it back to spacetime to build an invariant Lagrangian; because $J^{1}E$ has `derivative coordinates', one naturally obtains operators with more than 2-derivatives from this geometry. We apply this formalism to various examples, including a single real scalar in 4d and a quartet of real scalars with $O(4)$ symmetry that describes the Higgs EFTs. We show how an entire non-redundant basis of 0-, 2-, and 4-derivative operators is obtained from jet bundle geometry in this way. Finally, we study the connection to amplitudes and the role of geometric invariants.

    hep-phhep-thmath-phmath.MPJ.Phys.A(2024)·31 citations
31. 31*

    The Basis Invariant Flavor Puzzle

    Miguel P. Bento🇵🇹 · Joao P. Silva🇵🇹 · Andreas Trautner🇩🇪

    The flavor puzzle of the Standard Model quark sector is formulated in a non-perturbative way, using basis invariants that are independent of the choice of quark field basis. To achieve this, we first derive the algebraic ring of 10 CP even (primary) and 1 CP odd (secondary) basis invariants, using the Hilbert series and plethystic logarithm. An orthogonal basis in the ring of basis invariants is explicitly constructed, using hermitian projection operators derived via birdtrack diagrams. The thereby constructed invariants have well defined CP transformation behavior and give the most direct access to the flavor symmetric alignments of basis covariants. We firstly "measure" the orthogonal basis invariants from experimental data and characterize their location in the available parameter space. The experimentally observed orthogonal basis invariants take very close to maximal values and are highly correlated. Explaining the location of the invariants at close to maximal points, including the associated miniscule and highly correlated deviations, corresponds to solving the flavor puzzle in the invariant language. Once properly normalized, the orthogonal basis invariants are close to scale (RGE) invariant, hence, provide exquisite targets for fits of both, low- and high-scale (bottom-up and top-down) flavor models. Our result provides an entirely new angle on the flavor puzzle, and opens up ample opportunities for its ultimate exploration.

    hep-phhep-exJHEP(2024)·16 citations
32. 32*

    Back-to-back inclusive dijets in DIS at small $x$: Complete NLO results and predictions

    Paul Caucal🇫🇷 · Farid Salazar🇺🇸 · Björn Schenke🇺🇸 · Tomasz Stebel🇵🇱 · Raju Venugopalan🇺🇸

    We compute the back-to-back dijet cross-section in deep inelastic scattering (DIS) at small $x$ to next-to-leading order (NLO) in the Color Glass Condensate effective field theory. Our result can be factorized into a convolution of the Weizsäcker-Williams gluon transverse momentum dependent distribution function (WW gluon TMD) with a universal soft factor and an NLO coefficient function. The soft factor includes both double and single logarithms in the ratio of the relative transverse momentum $P_{\perp }$ of the dijet pair to the dijet momentum imbalance $q_{\perp }$; its renormalization group (RG) evolution is resummed into the Sudakov factor. Likewise, the WW TMD obeys a nonlinear RG equation in $x$ that is kinematically constrained to satisfy both lifetime and rapidity ordering of the projectile. Exact analytical expressions are obtained for the NLO coefficient function of transversely and longitudinally polarized photons. Our results allow for the first quantitative separation of the dynamics of Sudakov suppression from that of gluon saturation. They can be extended to other final states and provide a framework for precision tests of novel QCD many-body dynamics at the Electron-Ion Collider.

    hep-phnucl-thPRL(2024)·83 citations
33. 33*

    On the positivity of MSbar parton distributions

    Alessandro Candido🇮🇹 · Stefano Forte🇮🇹 · Tommaso Giani🇳🇱 · Felix Hekhorn🇮🇹

    We revisit our argument that shows that parton distribution Functions (PDFs) in the MSbar{ scheme are non-negative in the perturbative region, with the main goals of elucidating its domain of validity and clarifying its theoretical underpinnings. We specifically discuss recent results proving that PDFs can turn negative at sufficiently low scale, we clarify quantitatively various aspects of our derivation of positivity in the perturbative region, and we provide an estimate for the scale above which PDF positivity holds.

    hep-phhep-exEPJC(2024)·32 citations
34. 34*

    Returning CP-Observables to The Frames They Belong

    Jona Ackerschott🇩🇪 · Rahool Kumar Barman🇺🇸 · Dorival Gonçalves🇺🇸 · Theo Heimel🇩🇪 · Tilman Plehn🇩🇪

    Optimal kinematic observables are often defined in specific frames and then approximated at the reconstruction level. We show how multi-dimensional unfolding methods allow us to reconstruct these observables in their proper rest frame and in a probabilistically faithful way. We illustrate our approach with a measurement of a CP-phase in the top Yukawa coupling. Our method makes use of key advantages of generative unfolding, but as a constructed observable it fits into standard LHC analysis frameworks.

    hep-phSciPost Phys.(2024)·40 citations
35. 35*

    A Formalism for Extracting Track Functions from Jet Measurements

    Kyle Lee🇺🇸 · Ian Moult🇺🇸 · Felix Ringer🇺🇸 · Wouter J. Waalewijn🇳🇱

    The continued success of the jet substructure program will require widespread use of tracking information to enable increasingly precise measurements of a broader class of observables. The recent reformulation of jet substructure in terms of energy correlators has simplified the incorporation of universal non-perturbative matrix elements, so called "track functions", in jet substructure calculations. These advances make it timely to understand how these universal non-perturbative functions can be extracted from hadron collider data, which is complicated by the use jet algorithms. In this paper we introduce a new class of jet functions, which we call (semi-inclusive) track jet functions, which describe measurements of the track energy fraction in identified jets. These track jet functions can be matched onto the universal track functions, with perturbatively calculable matching coefficients that incorporate the jet algorithm dependence. We perform this matching, and present phenomenological results for the charged energy fraction in jets at the LHC and EIC/HERA at collinear next-to-leading logarithmic accuracy. We show that higher moments of the charged energy fraction directly exhibit non-linear Lorentzian renormalization group flows, allowing the study of these flows with collider data. Our factorization theorem enables the extraction of universal track functions from jet measurements, opening the door to their use for a precision jet substructure program.

    hep-phhep-exnucl-exnucl-thJHEP(2024)·26 citations
36. 36*

    Electroweak mass difference of mesons

    Antonio Pich🇪🇸 · Arthur Platschorre🇬🇧 · Mario Reig🇬🇧

    We consider electroweak (EW) gauge boson corrections to the masses of pseudoscalar mesons to next to leading order (NLO) in ${\alpha }_s$ and $1/N_C$. The pion mass shift induced by the $Z$-boson is shown to be $m_{{\pi }^{\pm }}-m_{{\pi }^0}=-0.00201(12)$ MeV. While being small compared to the electromagnetic mass shift, the prediction lies about a factor of $\sim 4$ above the precision of the current experimental measurement, and a factor $O(10)$ below the precision of current lattice calculations. This motivates future implementations of these EW gauge boson effects on the lattice. Finally, we consider BSM contributions to the pion mass difference.

    hep-phhep-latPRD(2023)·1 citation
37. 37*

    Insights on the current semi-leptonic $B$-decay discrepancies -- and how $B_s\to {\mu }^{+}{\mu }^{-}\gamma$ can help

    Diego Guadagnoli🇫🇷 · Camille Normand🇫🇷 · Silvano Simula🇮🇹 · Ludovico Vittorio🇫🇷

    $B_s\to {\mu }^{+}{\mu }^{-}\gamma$, measured at high $q^2$ as a partially reconstructed decay, can probe the origin of the existing discrepancies in semi-leptonic $b\to s$ and $b\to c$ decays. We perform a complete study of this possibility. We start by reassessing the alleged discrepancies, with a focus on a unified EFT description. Using the SMEFT, we find that the tauonic Wilson coefficient required by $R(D^{(\ast )})$ implies a universal muonic Wilson coefficient of precisely the size required by semi-muonic BR data and, separately, by semi-muonic angular analyses. We thus identify reference scenarios. Importantly, $B_s\to {\mu }^{+}{\mu }^{-}\gamma$ offers a strategy to access them without being affected by the long-distance issues that hamper the prediction of semi-leptonic $B$ decays at low $q^2$. After quantifying to the best of our knowledge the $B_s\to {\mu }^{+}{\mu }^{-}\gamma$ experimental over the long haul, we infer the $B_s\to {\mu }^{+}{\mu }^{-}\gamma$ sensitivity to the couplings relevant to the anomalies. In the example of the real-$\delta C_{9,10}$ scenario, we find significances below 3$\sigma$. Such figure is to be compared with other single-observable sensitivities that one can expect from e.g. BR and angular data, whether at low or high $q^2$, and not affected by long-distance issues such as narrow resonances or intermediate charmed di-meson rescattering.

    hep-phhep-exhep-latJHEP(2023)·29 citations
38. 38*

    EFT matching from analyticity and unitarity

    Stefano De Angelis🇫🇷 · Gauthier Durieux🇨🇭

    We present a new on-shell method for the matching of ultraviolet models featuring massive states onto their massless effective field theory. We employ a dispersion relation in the space of complex momentum dilations to capture, in a single variable, the relevant analytic structure of scattering amplitudes at any multiplicity. Multi-variate complex analysis and crossing considerations are therefore avoided. Remarkably, no knowledge about the infrared effective field theory is required in dimensional regularisation. All matching information is extracted from the residues and discontinuities of the ultraviolet scattering amplitudes, which unitarity expresses in terms of lower-point and lower-loop results, respectively. This decomposition into simpler building blocks could deliver new insights in the structure of the effective field theories obtained from classes of ultraviolet scenarios and facilitate computations at higher loop orders.

    hep-phhep-thSciPost Phys.(2024)·31 citations
39. 39*

    From ray to spray: augmenting amplitudes and taming fast oscillations in fully numerical neutrino codes

    Michele Maltoni🇪🇸

    In this note we describe how to complement the neutrino evolution matrix calculated at a given energy and trajectory with additional information which allows to reliably extrapolate it to nearby energies or trajectories without repeating the full computation. Our method works for arbitrary matter density profiles, can be applied to any propagation model described by an Hamiltonian, and exactly guarantees the unitarity of the evolution matrix. As a straightforward application, we show how to enhance the calculation of the theoretical predictions for experimentally measured quantities, so that they remain accurate even in the presence of fast neutrino oscillations. Furthermore, the ability to "move around" a given energy and trajectory opens the door to precise interpolation of the oscillation amplitudes within a grid of tabulated values, with potential benefits for the computation speed of Monte-Carlo codes. We also provide a set of examples to illustrate the most prominent features of our approach.

    hep-phhep-exJHEP(2023)·7 citations
40. 40*

    The generation of high-energy electron-positron pairs during the Breit-Wheeler resonant process in a strong field of an X-ray electromagnetic wave

    S.P. Roshchupkin🇷🇺 · V.D. Serov🇷🇺 · V.V. Dubov🇷🇺

    The Breith-Wheeler resonant process has been theoretically studied in a strong X-ray electromagnetic wave field under conditions when the energy of one of the initial high-energy gamma quanta passes into the energy of a positron or electron. These resonant conditions have been studied in detail. Analytical formulas for the resonant differential cross-section of channels A and B of the reaction are obtained. It is shown that the resonant differential cross-section significantly depends on the value of the characteristic Breit-Wheeler energy, which is determined by the parameters of the electromagnetic wave and the initial gamma quanta. With a decrease in the characteristic Breit-Wheeler energy, the resonant cross-section increases sharply and may exceed the corresponding non-resonant cross-section by several orders of magnitude.

    hep-phphysics.plasm-phSymmetry(2023)·1 citation
41. 41*

    W0_sample = np.random.normal(0,1)?

    Julian Ebelt🇩🇪 · Sven Krippendorf🇩🇪 · Andreas Schachner🇺🇸

    In this note we explore the distribution of vacuum expectation values of the superpotential $W_0$ in explicit Type IIB flux compactifications. We show that the distribution can be approximated, universally across geometries, by a two-dimensional Gaussian with a model dependent standard deviation. We identify this behaviour in 20 Calabi-Yau orientifold compactifications with between two and five complex structure moduli by constructing a total of $\mathcal{O}(10^7)$ flux vacua. We observe a characteristic scaling behaviour of the width $\sigma$ of our distributions with respect to the D3-charge contributions $N_{\text{flux}}$ from fluxes which can be approximated by $\sigma \sim \sqrt{N_{\text{flux}}}$. This $W_0$ distribution implies that locating small values of $|W_0|$ as a preferred regime associated with classes of string theory solutions typically featuring hierarchies, simplifies to the basic statement of finding small Euclidean norms of normally distributed values. We do also identify small modifications to this Gaussian behaviour in our samples which might be seen as indications for the breakdown of the continuous flux approximation commonly used in the context of statistical analyses of the flux landscape.

    ↳ hep-thhep-phPLB(2024)·18 citations
42. 42*

    Chiral effects: new trends

    G. Yu. Prokhorov🇷🇺 · O. V. Teryaev🇷🇺 · V. I. Zakharov🇷🇺

    By chiral effects one understands manifestations of chiral gauge anomaly and of gravitational chiral anomaly in hydrodynamics. In recent two-three years our understanding of the chiral effects has considerably changed. Here we present mini-review of two topics. First, shift in understanding symmetry which underlies the chiral magnetic effect and, second, interpretation of the chiral kinematical effect uncovered recently.

    ↳ hep-thgr-qchep-phnucl-th0 citations
43. 43*

    Meson-exchange currents in quasielastic electron scattering in a generalized superscaling approach

    Paloma R. Casale🇪🇸 · J.E. Amaro🇪🇸 · M.B. Barbaro🇮🇹

    We present a model that incorporates the effect of two-body currents in quasielastic electron-nucleus scattering within the framework of a consistent superscaling formalism. This is achieved by defining an averaged single-nucleon hadronic tensor based on the 1p1h matrix element of the one-body current plus meson-exchange currents (MEC). The consistent treatment of one- and two-body currents in our model enables the calculation of exchange current effects in the kinematical region where the Fermi gas response is zero, but not the scaling function. The effect of MEC is consistently taken into account when extracting the phenomenological scaling function from electron scattering data. With this model, we investigate the effect of MEC on the response functions taking into account the effective mass of the nucleon, and examine the consequences it has on the inclusive $(e,e^{\prime })$ cross section. We find that 1p1h MEC deplete the quasielastic transverse response, while they not alter significantly the scaling behavior of (e,e') data.

    ↳ nucl-thhep-phSymmetry(2023)·10 citations
44. 44*

    Comment on "Electromagnetic form factors for nucleons in short-range correlations": arXiv:2305.13666

    Dmitry N. Kim (1) · Or Hen (2) · Gerald A. Miller (1) · E. Piasetzky (3) · M. Strikman (4) · L. Weinstein (5) ((1) Department of Physics, University of Washington, Seattle, WA 98195-1560, USA (2) Department of Physics, Massachusetts Institute of Technology, Cambridge Massachusetts 02139, USA (3) School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel (4) Department of Physics, The Pennsylvania State University, Norfolk, Virginia, 23529, USA (5) Department of Physics, Old Dominion University, Norfolk, Virginia, 23529, USA)

    The relationship between medium modifications of nuclear quark structure functions and medium modifications of elastic electromagnetic form factors is shown to be model dependent.

    ↳ nucl-thhep-exhep-phnucl-ex1 citation
45. 45*

    Gauge-independent transition dividing the confinement phase in the lattice SU(2) gauge-adjoint scalar model

    Akihiro Shibata🇯🇵 · Kei-Ichi Kondo🇯🇵

    The lattice SU(2) gauge-scalar model with the scalar field in the adjoint representation of the gauge group has two completely separated confinement and Higgs phases according to the preceding studies based on numerical simulations which have been performed in the specific gauge fixing based on the conventional understanding of the Brout-Englert-Higgs mechanism. In this paper, we re-examine this phase structure in the gauge-independent way based on the numerical simulations performed without any gauge fixing. This is motivated to confirm the recently proposed gauge-independent Brout-Englert-Higgs mechanism for generating the mass of the gauge field without relying on any spontaneous symmetry breaking. For this purpose we investigate correlation functions between gauge-invariant operators obtained by combining the original adjoint scalar field and the new field called the color-direction field which is constructed from the gauge field based on the gauge-covariant decomposition of the gauge field due to Cho-Duan-Ge-Shabanov and Faddeev-Niemi. Consequently, we reproduce gauge-independently the transition line separating confinement phase and Higgs phase, and show surprisingly the existence of a new transition line that divides completely the confinement phase into two parts. Finally, we discuss the physical meaning of the new transition and implications to confinement mechanism.

    ↳ hep-lathep-phhep-thPRD(2024)·5 citations
46. 46*

    Constraining Cosmological Phase Transitions with Chinese Pulsar Timing Array Data Release 1

    Deng Wang🇪🇸

    The Chinese Pulsar Timing Array (CPTA) collaboration has recently reported the observational evidence of a stochastic gravitational wave background. In light of the latest CPTA observation, we aim at exploring the ability of CPTA in probing new physics. Specifically, we constrain the first-order cosmological phase transitions with CPTA data, and find that the constraining result is slightly tighter than that of NANOGrav's 12.5-yr data but weaker than NANOGrav's 15-yr data. Considering the possible complexity of gravitational wave sources, we give the constraint on a mixed scenario of cosmological phase transitions and astrophysical supermassive binary black holes. Our analysis suggests that CPTA has a great potential to probe fundamental physics in the near future.

    ↳ astro-ph.COgr-qchep-phhep-th21 citations
47. 47*

    Spin-Induced Interactions and Heavy-Quark Transport in the QGP

    Zhanduo Tang🇺🇸 · Ralf Rapp🇺🇸

    A previously constructed $T$-matrix approach for studying the quark-gluon plasma (QGP) is improved by incorporating spin-dependent interactions between partons. These interactions arise from the relativistic corrections to the Cornell potential. We first study the vacuum spectroscopy of quarkonia with this potential and find that a significant admixture of a vector component in the confining potential (rather than the previously considered scalar interaction) improves the description of the experimental mass splittings in $S$- and $P$-wave states. The in-medium potential containing the vector component in the confining interaction is constrained by fitting lattice-QCD results for heavy-quark (HQ) free energies and the equation of state (EoS) computed within in the selfconsistent $T$-matrix framework. We subsequently extract the transport coefficients for charm quarks in the QGP with the improved in-medium potentials. The relativistic corrections to the vector component of the confining potential cause a notable increase in the thermal relaxation rate of charm quarks in the QGP in comparison to previous calculations, especially at high momenta. These results are expected to have significant ramifications for the phenomenology of open heavy-flavor observables at RHIC and the LHC.

    ↳ nucl-thhep-phPoS(2024)·1 citation
48. 48*

    Extreme mass-ratio inspirals into black holes surrounded by scalar clouds

    Richard Brito🇵🇹 · Shreya Shah🇩🇪

    We study extreme mass-ratio binary systems in which a stellar mass compact object spirals into a supermassive black hole surrounded by a scalar cloud. Scalar clouds can form through superradiant instabilities of massive scalar fields around spinning black holes and can also serve as a proxy for dark matter halos. Our framework is fully relativistic and assumes that the impact of the cloud on the geometry can be treated perturbatively. As a proof of concept, here we consider a point particle in circular, equatorial motion around a non-spinning black hole surrounded either by a spherically symmetric or a dipolar non-axisymmetric scalar cloud, but the framework can in principle be generalized to generic black hole spins and scalar cloud geometries. We compute the leading-order power lost by the point particle due to scalar radiation and show that, in some regimes, it can dominate over gravitational-wave emission. We confirm the presence of striking signatures due to the presence of a scalar cloud that had been predicted using Newtonian approximations, such as resonances that can give rise to sinking and floating orbits, as well as "sharp features" in the power lost by the particle at given orbital radii. Finally, for a spherically symmetric scalar cloud, we also compute the leading-order corrections to the black-hole geometry and to the gravitational-wave energy flux, focusing only on axial metric perturbations for the latter. We find that, for non-compact clouds, the corrections to the (axial) gravitational-wave fluxes at high frequencies can be understood in terms of a gravitational-redshift effect, in agreement with previous works.

    ↳ gr-qcastro-ph.COastro-ph.HEhep-ph+1PRD(2023)·106 citations
49. 49*

    Cosmological Bounces Induced by a Fermion Condensate

    Giorgi Tukhashvili🇺🇸 · Paul J. Steinhardt🇺🇸

    We show that it is possible for fermion condensation of the Nambu-Jona-Lasinio type to induce a non-singular bounce that smoothly connects a phase of slow contraction to a phase of expansion. A chiral condensate -- a non-zero vacuum expectation value of the spinor bilinear $⟨\bar{\Psi }\Psi ⟩$ -- can form spontaneously after a slow contraction phase smooths and flattens the universe and the Ricci-curvature exceeds a critical value. In this approach, a high density of spin-aligned free fermions is not required, which avoids the problem of generating a large anisotropy and initiating chaotic mixmaster behavior during the bounce phase.

    ↳ gr-qcastro-ph.COhep-phhep-thPRL(2023)·25 citations
50. 50*

    Bose-Einstein Condensation and Black Holes in Dark Matter and Dark Energy

    Kemal Gültekin🇺🇸

    The main aim of this study is to reveal curved space and particle physics effects on the formation of Bose-Einstein condensate (BEC) scalar fields in cosmology and around a black hole. Cosmological scalar fields for dark energy and dark matter may be considered as a result of Bose-Einstein condensation. In this regard, our main attention will be devoted to BECs in curved space. By considering the dynamics of a BEC scalar field at a microscopic level, we first study the initial phase of the formation of condensation in cosmology. To this end, we initially introduce an effective Minkowski space formulation that enables considering only the effect of particle physics processes, excluding the effect of gravitational particle production and enabling us to see cosmological evolution more easily. Then, by using this formulation, we study a model with a trilinear coupling that induces the processes. After considering the phase evolution of the produced particles, we find that they evolve towards the formation of a BEC if some specific conditions are satisfied. In principle, the effective Minkowski space formulation introduced in this study can be applied to particle physics processes in any sufficiently smooth spacetime. In this regard, we also analyse if a BEC scalar field is realized in the spacetime around a Reissner - Nordström black hole. We find that the produced particles of particle physics processes are localized in a region around the black hole and have a tendency toward condensation if the emerged particles are much heavier than ingoing particles. We also find that such a configuration is phenomenologically viable only if the scalars and the black hole have dark electric charges. Finally, we consider gravitational collapse around Schwarzschild black holes and form a first step towards a study in future about the effects of gravitational collapse on Bose-Einstein condensation.

    ↳ gr-qcastro-ph.COhep-phhep-th2 citations
51. 51*

    CMB Polarization by the Asymmetric Template of Scalar Perturbations

    Jafar Khodagholizadeh🇮🇷 · Rohoollah Mohammadi🇮🇷 · S. M. S. Movahed🇮🇷

    Inspired by a dipole asymmetric template for the CMB temperature map in the primordial scalar fluctuations observed by Planck at a large scale, we examine the contribution of a similar template for power asymmetry in modifying the linear polarization pattern of CMB. Replacing un-modulated temperature fluctuation with dipolar modulated one in time evolution equations somehow breaks linear perturbation in the various components of the CMB map. This non-linearity allows deflecting CMB polarization in patterns that contain divergence-free components. The explicit expressions for the angular power spectra of the electric and magnetic-type parities of linear polarization are derived in the form of the line of sight integral solutions. Our results demonstrate that the electric-type polarization is modified and the magnetic-type polarization would be produced. Such imprints depend on the linear and square of the asymmetric amplitude for $E$- and $B$-modes power spectra, respectively. For the observed dipole template, the value of $B$ polarization spectrum at the large scale ($\ell \lesssim 10$) is almost equivalent to the power spectrum obtained from Compton scattering in the presence of tensor perturbation with tensor to scalar ratio about $r\simeq 0.005$.

    ↳ gr-qchep-phEPJC(2023)·3 citations
52. 52*

    Prediction of solar flares using neutrino detectors of the second generation

    Oleg Boyarkin🇧🇾 · Iren Boyarkina🇮🇹

    The physics-based method of forecasting the high energy solar flares (SFs) with the help of the neutrino detectors utilizing the coherent elastic neutrino-nucleus scattering (CE$\nu$NS) is considered. The behavior of the neutrino beams traveling through the coupled sunspots (CSs) being the sources of the future SFs is investigated. Two neutrino beams are included into consideration, namely, the ${\nu }_{eL}$ beam and the ${\nu }_{\mu L}$ beam which have been produced after the passage of the Micheev-Smirnov-Wolfenstein resonance. It is assumed that the neutrinos possess the charge radius, the magnetic and anapole moments while the CS magnetic field is vortex, nonhomogeneous and has twisting. Estimations of the weakening of the neutrino beams after traversing the resonant layers are given. It is demonstrated, that this weakening could be registered by the detectors employing CE$\nu$NS only when the neutrinos have the Dirac nature.

    ↳ astro-ph.SRhep-phProceedings of the National Academy of Sc…·0 citations
53. 53*

    Testing the first law of black hole mechanics with GW150914

    Deng Wang🇪🇸

    Whether the first law of black hole mechanics is correct is an important question in black holes physics. Subjected to current limited gravitational wave events, we propose its weaker version that permits a relatively large perturbation to a black hole system and implement a simple test with the first event GW150914. Confronting the strain data with the theory, we obtain the constraint on the deviation parameter $\alpha =0.07\pm 0.11$, which indicates that this weaker version is valid at the 68\% confidence level. This result implies that the first law of black hole mechanics may be correct.

    ↳ gr-qcastro-ph.COhep-phhep-th0 citations
54. 54*

    Cosmological First-Order Vacuum Phase Transitions in an Expanding Anisotropic Universe

    A. Savaş Arapoğlu🇹🇷 · A. Emrah Yükselci🇹🇷

    We examine the anisotropy originated from a first-order vacuum phase transitions through three-dimensional numerical simulations. We apply Bianchi Type-I metric to our model that has one scalar field minimally coupled to the gravity. We calculate the time evolution of the energy density for the shear scalar and the directional Hubble parameters as well as the power spectra for the scalar field and the gravitational radiation although there are a number of caveats for the tensor perturbations in Bianchi Type-I universe. We run simulations with different mass scales of the scalar field, therefore, in addition to investigation of anisotropy via the shear scalar, we also determine at which mass scale the phase transition completes successfully, hence, neglecting the expansion of the Universe does not significantly affect the results. Finally, we showed that such an event may contribute to the total anisotropy depending on the mass scale of the scalar field and the initial population of nucleated bubbles.

    ↳ gr-qcastro-ph.COhep-phPhys.Dark Univ.(2024)·2 citations
55. 55*

    Numerical analysis of a baryon and its dilatation modes in holographic QCD

    Keiichiro Hori (Kyoto U.)🇯🇵 · Hideo Suganuma (Kyoto U.)🇯🇵 · Hiroki Kanda (YITP, Kyoto U.)🇯🇵

    We investigate a baryon and its dilatation modes in holographic QCD based on the Sakai-Sugimoto model, which is expressed as a 1+4 dimensional U($N_f$) gauge theory in the flavor space. For spatially rotational symmetric systems, we apply a generalized version of the Witten Ansatz, and reduce 1+4 dimensional holographic QCD into a 1+2 dimensional Abelian Higgs theory in a curved space. In the reduced theory, the holographic baryon is described as a two-dimensional topological object of an Abrikosov vortex. We numerically calculate the baryon solution of holographic QCD using a fine and large lattice with spacing of 0.04 fm and size of 10 fm. Using the relation between the baryon size and the zero-point location of the Higgs field in the description with the Witten Ansatz, we investigate a various-size baryon through this vortex description. As time-dependent size-oscillation modes (dilatation modes) of a baryon, we numerically obtain the lowest excitation energy of 577 MeV and deduce the dilatational excitation of a nucleon to be the Roper resonance N${}^{\ast }$(1440).

    ↳ hep-thhep-phnucl-thPRD(2024)·3 citations
56. 56*

    Graph Structure from Point Clouds: Geometric Attention is All You Need

    Daniel Murnane🇺🇸

    The use of graph neural networks has produced significant advances in point cloud problems, such as those found in high energy physics. The question of how to produce a graph structure in these problems is usually treated as a matter of heuristics, employing fully connected graphs or K-nearest neighbors. In this work, we elevate this question to utmost importance as the Topology Problem. We propose an attention mechanism that allows a graph to be constructed in a learned space that handles geometrically the flow of relevance, providing one solution to the Topology Problem. We test this architecture, called GravNetNorm, on the task of top jet tagging, and show that it is competitive in tagging accuracy, and uses far fewer computational resources than all other comparable models.

    ↳ cs.LGhep-exhep-phphysics.comp-ph+12 citations
57. 57*

    Searching for High-Energy Neutrino Emission from Seyfert Galaxies in the Northern Sky with IceCube

    Theo Glauch · Ali Kheirandish · Tomas Kontrimas · Qinrui Liu · Hans Niederhausen (for the IceCube Collaboration)

    The recent detection of TeV neutrino emission from the nearby active galaxy NGC 1068 by IceCube suggests that AGN could make a sizable contribution to the total high-energy cosmic neutrino flux. The absence of TeV gamma rays from NGC 1068, indicates neutrino production originates in the innermost region of the AGN. Disk-corona models predict a correlation between neutrinos and keV X-rays in Seyfert galaxies, a subclass of AGN to which NGC 1068 belongs. Using 10 years of IceCube through-going track events, we report results from searches for neutrino signals from 27 additional sources in the Northern Sky by studying both the generic single power-law spectral assumption and spectra predicted by the disk-corona model. Our results show excesses of neutrinos associated with two sources, NGC 4151 and CGCG 420-015, at 2.7$\sigma$ significance, and at the same time constrain the collective neutrino emission from our source list.

    ↳ astro-ph.HEhep-phPoS(2023)·15 citations
58. 58*

    The geometry of inflationary observables: lifts, flows, equivalence classes

    Georgios K. Karananas🇩🇪 · Marco Michel🇮🇱 · Javier Rubio🇪🇸

    The Eisenhart lift allows to formulate the dynamics of a scalar field in a potential as pure geodesic motion in a curved field-space manifold involving an additional fictitious vector field. Making use of the formalism in the context of inflation, we show that the main inflationary observables can be expressed in terms of the geometrical properties of a two-dimensional uplifted field-space manifold spanned by the time derivatives of the scalar and the temporal component of the vector. This allows to abstract from specific potentials and models and describe inflation solely in terms of the flow of geometric quantities. Our findings are illustrated through several inflationary examples previously considered in the literature.

    ↳ gr-qcastro-ph.COhep-phhep-thPLB(2024)·6 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.