Mon·May 9, 2022Monday·May 9, 2022

1. 01*

   On the normalization of unintegrated parton densities

   Benjamin Guiot🇨🇱

   Recently, the definitions of the Kimber-Martin-Ryskin-Watt (KMRW) unintegrated parton densities (UPDFs) have been discussed by several groups. In the first part of this manuscript, we remind the issues encountered with these definitions and discuss the proposed solutions. In our opinion, none of these solutions is fully satisfactory. We observe that these issues seem to be related to the normalization condition where the UPDFs are related to the collinear PDFs by an integration over transverse momentum cut off by the factorization scale. Then, we build a modified version of the angular-ordering KMRW UPDFs, obeying the normalization condition with the transverse momentum integrated up to infinity and show that the usual issues are absent.

   hep-phPRD(2023)·15 citations
2. 02*

   Generating CP violation from a modified Fridberg-Lee model

   N. Razzaghi🇮🇷 · S. M. M. Rasouli🇵🇹 · P. Parada🇵🇹 · P. V. Moniz🇵🇹

   The overall characteristics of the solar and atmospheric neutrino oscillations are approximately consistent with a tribimaximal form of the mixing matrix $U$ of the lepton sector. Exact tribimaximal mixing leads to ${\theta }_{13}=0$. However, the results from the Daya Bay and RENO experiments have established, such that in comparison to the other neutrino mixing angles, ${\theta }_{13}$ is small. Moreover, the atmospheric and solar mass splitting differ by two orders of magnitude. These significant differences constitutes the great enthusiasm and main motivation for our research herein reported. Keeping the leading behavior of U as tribimaximal. We would make a response to the following questions: at some level, whether or not the small parameters such as the solar neutrino mass splitting and $U_{e3}$, which vanish in a new framework, can be interpreted as a modified FL neutrino mass model? Subsequently, a minimal single perturbation leads to nonzero values for both of them? Our minimal perturbation matrix is constructed solely from computing the third mass eigenstate, using the rules of perturbation theory. Let us point out that in contrast with~\cite{my}, this matrix is not ad hoc assumed, but is instead built following a series of steps we will outline. Also in compared to the original FL neutrino mass model which generalize it by inserting phase factors, our work is more accurate. Subsequently, we produce the following results that add new contributions to the literature: a) we obtain a realistic neutrino mixing matrix with $\delta \ne 0$ and ${\theta }_{23}=45^{\circ }$; b) the solar mass splitting term is dominated by an imaginary term, which could induce the existence of Majorana neutrinos, along with explaining a large CP violation in nature.

   hep-phUniverse(2022)·4 citations
3. 03*

   Inflaton Dark Matter

   Jong-Hyun Yoon🇫🇮

   We discuss a minimal extension of the Standard Model (SM) where a single real scalar field serves as both inflaton and dark matter. The corresponding Lagrangian contains the renormalizable interactions of the inflaton field. Quantum effects generally induce a non-minimal coupling to gravity which facilitates inflation consistent with the PLANCK constraints. A large fraction of the inflaton quanta produced after inflation must be converted into the SM radiation reheating the Universe and the rest remains dark matter today. We consider thermal and non-thermal production of inflaton dark matter. In the non-thermal case, we take into account collective effects with the help of lattice simulations. Combining analytic and numerical results with the unitarity consideration, we find that the inflaton dark matter model is viable only in the thermal case where the inflaton mass is near half the Higgs mass.

   hep-phastro-ph.COPoS(2022)·0 citations
4. 04*

   Model-independent study on the anomalous $ZZ\gamma$ and $Z\gamma \gamma$ couplings at the future muon collider

   A. Senol🇹🇷 · S. Spor🇹🇷 · E. Gurkanli🇹🇷 · V. Cetinkaya🇹🇷 · H. Denizli🇹🇷 · M. Köksal🇹🇷

   In this study, we investigate the potential of ${\mu }^{-}{\mu }^{+}\to Z\gamma \to \nu \bar{\nu }\gamma$ process at the future muon collider with a center-of-mass energy of 3 TeV to examine the anomalous $ZZ\gamma$ and $Z\gamma \gamma$ neutral triple gauge couplings defining $CP$-conserving $C_{\tilde{B}W}/{\Lambda }^4$ coupling and three $CP$-violating $C_{BB}/{\Lambda }^4$, $C_{BW}/{\Lambda }^4$, $C_{WW}/{\Lambda }^4$ couplings. All signal and relevant background events are generated in MadGraph and passed through Pythia for parton showering and hadronization. Detector effects are also considered via tuned muon detector cards in Delphes. The effects of systematic uncertainties of $0\%$, $3\%$ and $5\%$ on the sensitivities are studied. The best sensitivities obtained from the process ${\mu }^{-}{\mu }^{+}\to Z\gamma \to \nu \bar{\nu }\gamma$ are $[-6.53;6.64]\times 10^{-2}$ TeV${}^{-4}$ on $CP$-conserving $C_{\tilde{B}W}/{\Lambda }^4$ coupling and $[-2.47;2.47]\times 10^{-2}$ TeV${}^{-4}$, $[-8.46;8.46]\times 10^{-2}$ TeV${}^{-4}$ and $[-2.20;2.20]\times 10^{-1}$ TeV${}^{-4}$ on $CP$-conserving $C_{BB}/{\Lambda }^4$, $C_{BW}/{\Lambda }^4$, $C_{WW}/{\Lambda }^4$ couplings , respectively. Our obtained results on the anomalous neutral gauge couplings set more stringent sensitivity, ranging between 5 and 15 times than the current experimental results while slightly better than the phenomenological studies at future pp colliders such as the HL-LHC, the HE-LHC and the FCC-hh, respectively. On the other hand, we can see that the bounds on the anomalous neutral gauge couplings expected to be obtained for the future $e^{-}{e}^{+}$ colliders such as the CLIC are roughly 2 times better than our results.

   hep-phEur.Phys.J.Plus(2022)·18 citations
5. 05*

   New physics in $\text{b}\to \text{s}$ transitions in the MF331 model

   N. T. Duy🇻🇳 · P. N. Thu🇻🇳 · D. T. Huong🇻🇳

   There are two sources that help to explain the ${\text{R}}_{\text{K}}$, ${\text{R}}_{{\text{K}}^{\ast }}$ anomalies in the MF331 model. The first is non-LFUV couplings of the new neutral gauge boson ${\text{Z}}^{\prime }$ with leptons, ${\text{g}}^{{\text{Z}}^{\prime }}(e)\ne {\text{g}}^{{\text{Z}}^{\prime }}(\mu ,\tau )$, which causes the ${\text{R}}_{\text{K}}$, ${\text{R}}_{{\text{K}}^{\ast }}$ anomalies via ${\text{Z}}^{\prime }$-penguin diagrams involving newly charged gauge bosons ${\text{X}}_{\mu }^{\pm }$, and exotic U-quarks. The box diagram's contribution is the second source, which induced only the first lepton generation. We show that the penguin diagrams can not explain ${\text{R}}_{\text{K}}$, ${\text{R}}_{{\text{K}}^{\ast }}$ anomalies, and that the box diagram is required. The experimental constraints for ${\text{R}}_{\text{K}}$ and ${\text{R}}_{{\text{K}}^{\ast }}$ result in new particle mass degeneracy. The contributions of NP to the branching ratios $\text{Br}(\text{B}\to {\mu }^{+}{\mu }^{-}),\text{Br}(\text{b}\to s\gamma )$ predict results that agree with the experimental limits in the allowed region of the NP scale.

   hep-phEPJC(2022)·8 citations
6. 06*

   Reduction with Degenerate Gram matrix for One-loop Integrals

   Bo Feng🇨🇳 · Chang Hu🇨🇳 · Tingfei Li🇨🇳 · Yuekai Song🇨🇳

   An improved PV-reduction method for one-loop integrals with auxiliary vector $R$ has been proposed in \cite{Feng:2021enk,Hu:2021nia}. It has also been shown that the new method is a self-completed method in \cite{Feng:2022uqp}. Analytic reduction coefficients can be easily produced by recursion relations in this method, where the Gram determinant appears in denominators. The singularity caused by Gram determinant is a well-known fact and it is important to address these divergences in a given frame. In this paper, we propose a systematical algorithm to deal with this problem in our method. The key idea is that now the master integral of the highest topology will be decomposed into combinations of master integrals of lower topologies. By demanding the cancellation of divergence for obtained general reduction coefficients, we solve decomposition coefficients as a Taylor series of the Gram determinant. Moreover, the same idea can be applied to other kinds of divergences.

   hep-phJHEP(2022)·16 citations
7. 07*

   J-PARC hadron physics and future possibilities on color transparency

   S. Kumano🇯🇵

   The J-PARC is a hadron-accelerator facility to provide secondary beams of kaons, pions, neutrinos, muons, and the others together with the primary proton beam for investigating a wide range of science projects. High-energy hadron physics can be studied by using high-momentum beams of unseparated hadrons, which are essentially pions, and also primary protons. In this report, possible experiments are explained on color transparency and generalized parton distributions (GPDs). These projects are complementary to lepton-scattering experiments at JLab, COMPASS/AMBER, and future electron-ion colliders. Because of hadron-beam energies up to 30 GeV, the J-PARC is a unique facility to investigate the transition region from the hadron degrees of freedom to the quark-gluon one. It is suitable for finding mechanisms of the color transparency. Such color-transparency studies are also valuable for clarifying factorization of hadron-production processes in extracting the GPDs from actual measurements. These studies will lead to the understanding of basic high-energy hadron interactions in nuclear medium and to clarifications on the origins of hadron spins, masses, and internal pressure mechanisms.

   hep-phhep-exhep-latnucl-ex+1MDPI Physics(2022)·9 citations
8. 08*

   Thermodynamics and quark condensates of three-flavor QCD at low temperature

   Jens O. Andersen🇳🇴 · Qing Yu🇨🇳 · Hua Zhou🇨🇳

   We use three-flavor chiral perturbation theory ($\chi$PT) to calculate the pressure, light and $s$-quark condensates of QCD in the confined phase at finite temperature to $\mathcal{O}(p^6)$ in the low-energy expansion. We also include electromagnetic effects to order $e^2$, where the electromagnetic coupling $e$ counts as order $p$. Our results for the pressure and the condensates suggest that $\chi$PT converges very well for temperatures up to approximately 150 MeV. We combine $\chi$PT and the Hadron Resonance Gas (HRG) model by adding heavier baryons and mesons. Our results are compared with lattice simulations an d the agreement is very good for temperatures below {170} MeV, in contrast to the results from $\chi$PT which agree with the lattice only up to $T\approx 120$ MeV. Our value for the chiral crossover temperature is 160.1 MeV, which compares favorably to the lattice result of $157.3$ MeV.

   hep-phhep-latPRD(2023)·2 citations
9. 09*

   Fermion mass hierarchy and lepton flavor violation using $CP$ symmetry

   Joy Ganguly🇮🇳

   We present a model which employs $CP\times Z_3$ symmetries where quark mixing and charged leptons masses are explained by following some texture. To achieve neutrino mass and mixing, we write a non-renormalizable Lagrangian using type-II seesaw mechanism by assuming $\mathcal{O}(1)$ couplings predicting no $CP$ violation. Then, we calculate the value of the couplings for both normal and inverted ordering of neutrino masses. We propose a mechanism of ultra-violet (UV) completion that motivates the higher dimensional Lagrangian in the neutrino sector. We also calculate the branching fraction of lepton flavor violating decays driven by triplet scalar for the model. Later, it is shown that the model can also accommodate maximal $CP$ violation by breaking the $CP$ symmetry spontaneously.

   hep-phInt.J.Mod.Phys.A(2022)·4 citations
10. 10*

    Rapidity evolution of TMDs with running coupling

    Ian Balitsky🇺🇸 · Giovanni A. Chirilli🇩🇪

    The scale of a coupling constant for rapidity-only evolution of transverse-momentum dependent (TMD) operators in the Sudakov kinematic region is calculated using the Brodsky-Lepage-Mackenzie (BLM) optimal scale setting. The effective argument of a coupling constant is halfway in the logarithmical scale between the transverse momentum and energy of TMD distribution. The resulting rapidity-only evolution equation is solved for quark and gluon TMDs.

    hep-phhep-thPRD(2022)·11 citations
11. 11*

    False vacuum decay: an introductory review

    Federica Devoto🇬🇧 · Simone Devoto🇮🇹 · Luca Di Luzio🇮🇹 · Giovanni Ridolfi🇮🇹

    We review the description of tunnelling phenomena in the semi-classical approximation in ordinary quantum mechanics and in quantum field theory. In particular, we describe in detail the calculation, up to the first quantum corrections, of the decay probability per unit time of a metastable ground state. We apply the relevant formalism to the case of the standard model of electroweak interactions, whose ground state is metastable for sufficiently large values of the top quark mass. Finally, we discuss the impact of gravitational interactions on the calculation of the tunnelling rate.

    hep-phhep-thJ.Phys.G(2022)·63 citations
12. 12*

    Conductivity, diffusivity, and violation of Wiedemann-Franz Law in a hadron resonance gas with van der Waals interactions

    Kshitish Kumar Pradhan🇮🇳 · Dushmanta Sahu🇮🇳 · Ronald Scaria🇮🇳 · Raghunath Sahoo🇮🇳

    In this work, a hadron resonance gas under van der Waals (VDW) interactions has been studied. Both attractive and repulsive interactions between the meson-meson and (anti)baryon-(anti)baryon have been taken into consideration. Various transport properties such as electrical conductivity (${\sigma }_{\mathrm{el}}$) and thermal conductivity (${\kappa }_{\mathrm{th}}$) have been estimated by solving the Boltzmann transport equation under the relaxation time approximation. The effect of baryochemical potential (${\mu }_{\mathrm{B}}$) and temperature is also explicitly explored for the mentioned observables. Comparisons have been made with the results obtained from other existing theoretical models. We observe the violation of Wiedemann-Franz law in a hadron resonance gas at a high-temperature regime. The corresponding diffusivities have also been estimated, which can help us to understand the system in a better way.

    hep-phhep-exnucl-exnucl-thPRC(2023)·32 citations
13. 13*

    Matter effects on flavor transitions of high-energy astrophysical neutrinos based on typical propagation schemes

    Ding-Hui Xu🇨🇳 · Shu-Jun Rong🇨🇳

    Precise measurements of the flavor ratio of high energy astronomical neutrinos (HANs) would be promising in the following decades. Then matter effects and new physics effects on the flavor transition of HANs could be tested. In this paper, we examine matter effects on the flavor composition of HANs. The effects are dependent on propagation schemes and sources of neutrinos. We consider propagations in environments with adiabatically varying and constant electron density. In the adiabatic case, the matter influence on the flavor composition of HANs at Earth is noticeable at the electron density 10${}^{10}$ cm${}^{-3}$ in the cases of muon damping and neutron decaying sources. In contrast, in the constant density case, the matter effect can be neglected even at the density 10${}^{18}$ cm${}^{-3}$. Thus, observations from next-generation neutrino telescopes may set stringent constraints on the adiabatic propagation scheme.

    hep-phMod.Phys.Lett.A(2025)·2 citations
14. 14*

    Scrutinizing the 95-100 GeV di-tau excess in the top associated process

    Syuhei Iguro🇩🇪 · Teppei Kitahara🇯🇵 · Yuji Omura🇯🇵

    Recently, the CMS collaboration has reported a di-tau excess with a local significance of 2.6-3.1$\sigma$ where the invariant mass is $m_{\tau \tau }=$95-100 GeV. This excess can be interpreted as a light scalar boson that couples to the third generation fermions, particularly top and $\tau$. Based on the simplest model that can account for the CMS di-tau excess, we evaluate experimental sensitivities to the additional light resonance, using the results reported by the ATLAS collaboration. We see that a search for the top-quark associated production of the SM Higgs boson that decays into $\tau \bar{\tau }$ sets a strong model-independent limit. We also find that the CP-even scalar interpretation of the light resonance is excluded by the ATLAS results, while the CP-odd interpretation is not.

    hep-phhep-exEPJC(2022)·38 citations
15. 15*

    The decay widths of the $Z_{cs}(3985/4000)$ based on rigorous quark-hadron duality

    Zhi-Gang Wang🇨🇳

    In this work, we explore the hadronic coupling constants $G_{ZJ/\psi K}$, $G_{Z{\eta }_c{K}^{\ast }}$, $G_{Z{D}^{\ast }{\bar{D}}_s}$ of the exotic states $Z_{cs}(3985/4000)$ both in the pictures of the tetraquark states and molecular states with the tentative assignments $J^{PC}=1^{+-}$ based on the rigorous quark-hadron duality. Then we obtain the total widths ${\Gamma }_{Z_{cs}}^T=15.31\pm 2.06\mathrm{MeV}$ and ${\Gamma }_{Z_{cs}}^M=83.51\pm 21.09\mathrm{MeV}$, which are consistent with the experimental data $13.8_{-5.2}^{+8.1}\pm 4.9\mathrm{MeV}$ from the BESIII collaboration and $131\pm 15\pm 26\mathrm{MeV}$ from the LHCb collaboration, respectively, and support assigning the $Z_{cs}(3985)$ and $Z_{cs}(4000)$ to be the hidden-charm tetraquark state and molecular state with the $J^{PC}=1^{+-}$, respectively.

    hep-phCPC(2022)·18 citations
16. 16*

    Vacuum material properties and Cherenkov radiation in Logarithmic Electrodynamics

    P. Gaete🇨🇱 · J. A. Helayël-Neto🇧🇷

    We study some observational signatures of nonlinearities of the electromagnetic field. First to all we show the vital role played by nonlinearities in triggering a material behavior of the vacuum with $(\epsilon >0,\mu <0)$, which corresponds to a ferrimagnetic material. Secondly, the permittivity and susceptibility induced by nonlinearities are considered in order to obtain the refractive index via the dispersion relation for logarithmic electrodynamics. Finally, we consider the electromagnetic radiation produced by a moving charged particle interacting with a medium characterized by nonlinearities of the electromagnetic field. To this end we consider logarithmic electrodynamics. The result shows that the radiation is driven by the medium through which the particle travels like the one that happens in the Cherenkov effect.

    hep-phphysics.opticsEPJC(2023)·9 citations
17. 17*

    Towards the renormalisation of the Standard Model effective field theory to dimension eight: Bosonic interactions II

    Supratim Das Bakshi🇪🇸 · Mikael Chala🇪🇸 · Álvaro Díaz-Carmona🇪🇸 · Guilherme Guedes🇪🇸

    We calculate the renormalisation group running of the bosonic Standard Model (SM) effective operators at one loop and to order $v^4/{\Lambda }^4$, with $v\sim 246$ GeV being the electroweak scale and $\Lambda$ the unknown new physics threshold. We focus on contributions driven by one dimension-eight term and SM couplings, thus extending (and completing) the effort initiated in arXiv:2106.05291, in which quantum corrections from pairs of dimension-six interactions were considered. We highlight some interesting consequences, including the renormalisation of loop-induced interactions by tree-level generated terms and, more importantly, the validity of positivity bounds on different operators inducing anomalous gauge quartic couplings.

    hep-phhep-thEur.Phys.J.Plus(2022)·64 citations
18. 18*

    Composite two-Higgs doublet model from dilaton effective field theory

    Thomas Appelquist🇺🇸 · James Ingoldby🇮🇹 · Maurizio Piai🇬🇧

    We construct a composite two-Higgs-doublet model (2HDM) within the context of dilaton effective field theory. This EFT describes the particle spectrum observed in lattice simulations of a near-conformal $SU(3)$ gauge field theory. A second Higgs doublet is naturally accommodated within the EFT, used previously to construct a one-Higgs-doublet model. We explore the interplay of phenomenological and EFT requirements, supplemented by information from numerical lattice studies of the $SU(3)$ gauge theory with eight fundamental (Dirac) fermions. We build a viable model with moderate parameter tuning. In the relevant portion of parameter space, we match the model to a conventional general description of 2HDMs, and comment on the role of custodial symmetry (breaking) in the scalar potential. Contributions to the precision electroweak parameter $T$ provide a possible explanation for the recent measurement of the W-boson mass by CDF II.

    hep-phhep-latNPB(2022)·39 citations
19. 19*

    Evaluation of Feynman integrals with arbitrary complex masses via series expansions

    Tommaso Armadillo🇧🇪 · Roberto Bonciani🇮🇹 · Simone Devoto🇮🇹 · Narayan Rana🇮🇹 · Alessandro Vicini🇮🇹

    We present an algorithm to evaluate multiloop Feynman integrals with an arbitrary number of internal massive lines, with the masses being in general complex-valued, and its implementation in the \textsc{Mathematica} package \textsc{SeaSyde}. The implementation solves by series expansions the system of differential equations satisfied by the Master Integrals. At variance with respect to other existing codes, the analytical continuation of the solution is performed in the complex plane associated to each kinematical invariant. We present the results of the evaluation of the Master Integrals relevant for the NNLO QCD-EW corrections to the neutral-current Drell-Yan processes.

    hep-phComput.Phys.Commun.(2023)·111 citations
20. 20*

    Phonon-mediated Migdal effect in semiconductor detectors

    Zheng-Liang Liang🇨🇳 · Chongjie Mo🇨🇳 · Fawei Zheng🇨🇳 · Ping Zhang🇨🇳

    The Migdal effect inside detectors provides a new possibility of probing the sub-GeV dark matter (DM) particles. While there has been well-established methods treating the Migdal effect in isolated atoms, a coherent and complete description of the valence electrons in semiconductor is still absent. The bremstrahlung-like approach is a promising attempt, but it turns invalid for DM masses below a few tens of MeV. In this paper, we lay out a framework where phonon is chosen as an effective degree of freedom to describe the Migdal effect in semiconductors. In this picture, a valence electron is excited to the conduction state via exchange of a virtual phonon, accompanied by a multi-phonon process triggered by an incident DM particle. Under the incoherent approximation, it turns out that this approach can effectively push the sensitivities of the semiconductor targets further down to the MeV DM mass region.

    hep-phPRD(2022)·30 citations
21. 21*

    A first glance to the kinematic moments of $B\to X_c\ell \nu$ at third order

    Matteo Fael🇩🇪 · Kay Schönwald🇩🇪 · Matthias Steinhauser🇩🇪

    We study the impact of third-order QCD corrections for several kinematic moments of the inclusive semileptonic $B$ decays, to first order in the $1/m_b$ expansion. We consider the first four moments of the charged-lepton energy $E_{\ell }$ spectrum, the total leptonic invariant mass $q^2$ and the hadronic invariant mass $M_X^2$. No experimental cuts are applied. Our analytic results are obtained via an asymptotic expansion around the limit $m_b\simeq m_c$. After converting the scheme for the bottom mass to the kinetic scheme we compare the size of higher QCD corrections to the contributions from $1/m_b^2$ and $1/m_b^3$ power corrections and to the relative uncertainties.

    hep-phJHEP(2022)·39 citations
22. 22*

    Learning Uncertainties the Frequentist Way: Calibration and Correlation in High Energy Physics

    Rikab Gambhir🇺🇸 · Benjamin Nachman🇺🇸 · Jesse Thaler🇺🇸

    Calibration is a common experimental physics problem, whose goal is to infer the value and uncertainty of an unobservable quantity Z given a measured quantity X. Additionally, one would like to quantify the extent to which X and Z are correlated. In this paper, we present a machine learning framework for performing frequentist maximum likelihood inference with Gaussian uncertainty estimation, which also quantifies the mutual information between the unobservable and measured quantities. This framework uses the Donsker-Varadhan representation of the Kullback-Leibler divergence -- parametrized with a novel Gaussian Ansatz -- to enable a simultaneous extraction of the maximum likelihood values, uncertainties, and mutual information in a single training. We demonstrate our framework by extracting jet energy corrections and resolution factors from a simulation of the CMS detector at the Large Hadron Collider. By leveraging the high-dimensional feature space inside jets, we improve upon the nominal CMS jet resolution by upwards of 15%.

    hep-phhep-exphysics.data-anPRL(2022)·16 citations
23. 23*

    Conformal Colliders Meet the LHC

    Kyle Lee🇺🇸 · Bianka Meçaj🇺🇸 · Ian Moult🇺🇸

    The remarkably high energies of the Large Hadron Collider (LHC) have allowed for the first measurements of the shapes and scalings of multi-point correlators of energy flow operators, $⟨\Psi |\mathcal{E}({\vec{n}}_1)\mathcal{E}({\vec{n}}_2)\cdots \mathcal{E}({\vec{n}}_k)|\Psi ⟩$, providing new insights into the Lorentzian dynamics of quantum chromodynamics (QCD). In this Letter, we use recent advances in effective field theory to derive a rigorous factorization theorem for the light-ray density matrix, $\rho =|\Psi ⟩⟨\Psi |$, inside high transverse momentum jets at the LHC. Using the light-ray operator product expansion, the scaling behavior of multi-point correlators can be computed from the expectation value of the twist-2 spin-$J$ light-ray operators, ${\mathbb{O}}^{[J]}$, in this state, $\text{Tr}[\rho {\mathbb{O}}^{[J]}]$. We compute the light-ray density matrix at next-to-leading order, and combine this with results for the next-to-leading logarithmic scaling behavior of the correlators up to six-points, comparing with CMS Open Data. This theoretical accuracy allows us to resolve the quantum scaling dimensions of QCD light-ray operators inside jets at the LHC. Our factorization theorem for the light-ray density matrix at the LHC completes the link between recent developments in the study of energy correlators and LHC phenomenology, opening the door to a wide variety of precision jet substructure studies.

    hep-phhep-exnucl-exnucl-thPRD(2025)·133 citations
24. 24*

    Vortex String Formation in Black Hole Superradiance of a Dark Photon with the Higgs Mechanism

    William E. East🇨🇦

    Black hole superradiance, which only relies on gravitational interactions, can provide a powerful probe of the existence of ultralight bosons that are weakly coupled to ordinary matter. However, as a boson cloud grows through superradiance, nonlinear effects from interactions with itself or other fields may become important. As a representative example of this, we use nonlinear evolutions to study black hole superradiance of a vector boson that attains a mass, via a coupling to a complex scalar, through the Higgs mechanism. For the cases considered, we find that the superradiant instability can lead to a transient period where the scalar field reaches its symmetry restoration value, leading to the formation of closed vortex strings, the temporary disruption of the exponential growth of the cloud, and an explosive outburst of energy. After the cloud loses sufficient mass, the superradiant growth resumes, and the cycle repeats. Thus, the black hole will be spun down but, potentially, at a much lower rate compared to when nonlinear effects are unimportant, and with the liberated energy going primarily into bosonic radiation instead of gravitational waves.

    hep-phgr-qcPRL(2022)·58 citations
25. 25*

    Yang-Mills stars in Higgsed non-Abelian dark matter

    Mudit Jain🇺🇸

    Bosonic field theories with self interactions alongside gravity, generally admit bound states known as solitons. Depending upon the spin nature of the field, they can even carry macroscopic intrinsic spin polarization. Focusing on the SU($2$) case, we describe polarized solitons in non-Abelian theories with a heavy Higgs, which we refer to as `Yang-Mills stars'. Owing to both kinds of self-interactions; repulsive ones arising due to the Yang-Mills structure, while attractive ones arising due to the Higgs exchange; we can have a diverse zoo of solitons. Depending upon various parameters of the theory such as the mass of the Yang-Mills vector fields $m$, mass of the dark Higgs field $M_{\phi }$, and the gauge coupling constant $g$, these objects can be astrophysically large with varying size and mass, and carry large intrinsic spin and/or iso-spin giving rise to interesting phenomenological implications. Even for vector mass as large as $m\simeq 10$ eV, we can accommodate gauge couplings $g\lesssim 10^{-4}-10^{-5}$, still evading Bullet cluster constraints. For these parameters, there may exist cosmologically long lived solitons having radii as large as $r_s\sim 10^5{R}_{\odot }$ and masses $M_s\sim 10M_{\odot }$, carrying $M_s/m\sim 10^{66}$ amounts of intrinsic spin and iso-spin polarization. As a subset of the space of soliton solutions in the SU($2$) Higgs model, in the end we also explicitly discuss solitons in the Abelian Higgs model.

    hep-phastro-ph.COhep-thPRD(2022)·26 citations
26. 26*

    Probing High Scale Dirac Leptogenesis via Gravitational Waves from Domain Walls

    Basabendu Barman🇨🇴 · Debasish Borah🇮🇳 · Arnab Dasgupta🇺🇸 · Anish Ghoshal🇵🇱

    We propose a novel way of probing high scale Dirac leptogenesis, a viable alternative to canonical leptogenesis scenario where the total lepton number is conserved, keeping light standard model (SM) neutrinos purely Dirac. The simplest possible seesaw mechanism for generating light Dirac neutrinos involve heavy singlet Dirac fermions and a singlet scalar. In addition to unbroken global lepton number, a discrete $Z_2$ symmetry is imposed to forbid direct coupling between right and left chiral parts of light Dirac neutrino. Generating light Dirac neutrino mass requires the singlet scalar to acquire a vacuum expectation value (VEV) that also breaks the $Z_2$ symmetry, leading to formation of domain walls in the early universe. These walls, if made unstable by introducing a soft $Z_2$ breaking term, generate gravitational waves (GW) with a spectrum characterized by the wall tension or the singlet VEV, and the soft symmetry breaking scale. The scale of leptogenesis depends upon the $Z_2$-breaking singlet VEV which is also responsible for the tension of the domain wall, affecting the amplitude of GW produced from the collapsing walls. We find that most of the near future GW observatories will be able to probe Dirac leptogenesis scale all the way upto $10^{11}$ GeV.

    hep-phastro-ph.COPRD(2022)·59 citations
27. 27*

    The forward-backward asymmetry and differences of partial moments in inclusive semileptonic B decays

    Florian Herren🇺🇸

    Global fits to moments of kinematic distributions measured in inclusive semileptonic $B\to X_{c}l{\nu }_l$ enable the determination of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ together with non-perturbative matrix elements of the heavy quark expansion. In current fits, only two distinct kinematic distributions are employed and, as a consequence, higher moments of these distributions need to be taken into account to extract the relevant non-perturbative matrix elements. The moments of a given distribution are highly correlated and experimental uncertainties increase for higher moments. To address these issues, Turczyk suggested the inclusion of the charged lepton forward-backward asymmetry ${\mathcal{A}}_{FB}$ in global fits, since it provides information on non-perturbative parameters beyond the commonly used moments. It is possible to construct differences of partial moments of kinematic distributions, which can provide additional information on the non-perturbative parameters beyond ${\mathcal{A}}_{FB}$ and are studied in this work for the first time. Further, experimental cuts on the four-momentum transfer square are studied and are shown to preserve the shape of the angular distribution, in contrast to commonly used cuts on the lepton energy. Finally, the impact of final-state radiation and experimental lepton identification requirements on measurements of ${\mathcal{A}}_{FB}$ and differences of partial moments are discussed.

    hep-phhep-exSciPost Phys.(2023)·15 citations
28. 28*

    What has been learnt from the analysis of the low-energy pion-nucleon data during the past three decades?

    Evangelos Matsinos

    Over twenty-five years ago, two analyses of the pion-nucleon ($\pi N$) data at low energy (i.e., for pion laboratory kinetic energy $T\le 100$ MeV) reported on the departure of the extracted scattering amplitudes, corresponding to the two elastic-scattering reactions ${\pi }^{\pm }p\to {\pi }^{\pm }p$ and to the ${\pi }^{-}p$ charge-exchange reaction ${\pi }^{-}p\to {\pi }^{0}n$, from the triangle identity, which these amplitudes fulfil if the isospin invariance holds in the hadronic part of the $\pi N$ interaction. This discrepancy indicates that \emph{at least one} of the following assumptions is not valid: first, that the absolute normalisation of the bulk of the low-energy $\pi N$ datasets is correct; second, that any residual contributions to the corrections, which aim at the removal of the effects of electromagnetic (EM) origin from the measurements, are not significant; and third, that the isospin invariance holds in the hadronic part of the $\pi N$ interaction. In view of the incompatibility of the results of the various schemes of removal of the so-called trivial EM effects at the $\pi N$ threshold ($T=0$ MeV), the likelihood of residual effects of EM origin in the extracted $\pi N$ scattering amplitudes (from the data in the scattering region, i.e., above the $\pi N$ threshold) must be reassessed. This work emphasises the importance of the development of a unified scheme for the determination of reliable EM corrections, \emph{applicable at the $\pi N$ threshold and in the scattering region}, in providing a resolution to the established discrepancy at low energy.

    ↳ nucl-thhep-ph3 citations
29. 29*

    CMS PYTHIA 8 colour reconnection tunes based on underlying-event data

    CMS Collaboration

    New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the PYTHIA 8 event generator, are obtained based on the default CMS PYTHIA 8 underlying-event tune, CP5. Measurements sensitive to the underlying event performed by the CMS experiment at centre-of-mass energies $\sqrt{s}$ = 7 and 13 TeV, and by the CDF experiment at 1.96 TeV are used to constrain the parameters of colour reconnection models and multiple-parton interactions simultaneously. The new colour reconnection tunes are compared with various measurements at 1.96, 7, 8, and 13 TeV including measurements of the underlying-event, strange-particle multiplicities, jet substructure observables, jet shapes, and colour flow in top quark pair ($\mathrm{t}\bar{\mathrm{t}}$) events. The new tunes are also used to estimate the uncertainty related to colour reconnection modelling in the top quark mass measurement using the decay products of $\mathrm{t}\bar{\mathrm{t}}$ events in the semileptonic channel at 13 TeV.

    ↳ hep-exhep-phEPJC(2023)·71 citations
30. 30*

    Cosmology-informed neural networks to solve the background dynamics of the Universe

    Augusto T. Chantada🇦🇷 · Susana J. Landau🇦🇷 · Pavlos Protopapas🇺🇸 · Claudia G. Scóccola🇦🇷 · Cecilia Garraffo🇺🇸

    The field of machine learning has drawn increasing interest from various other fields due to the success of its methods at solving a plethora of different problems. An application of these has been to train artificial neural networks to solve differential equations without the need of a numerical solver. This particular application offers an alternative to conventional numerical methods, with advantages such as lower memory required to store solutions, parallelization, and, in some cases, a lower overall computational cost than its numerical counterparts. In this work, we train artificial neural networks to represent a bundle of solutions of the differential equations that govern the background dynamics of the Universe for four different models. The models we have chosen are $\Lambda \mathrm{CDM}$, the Chevallier-Polarski-Linder parametric dark energy model, a quintessence model with an exponential potential, and the Hu-Sawicki $f(R)$ model. We use the solutions that the networks provide to perform statistical analyses to estimate the values of each model's parameters with observational data; namely, estimates of the Hubble parameter from cosmic chronometers, type Ia supernovae data from the Pantheon compilation, and measurements from baryon acoustic oscillations. The results we obtain for all models match similar estimations done in the literature using numerical solvers. In addition, we estimate the error of the solutions that the trained networks provide by comparing them with the analytical solution when there is one, or to a high-precision numerical solution when there is not. Through these estimations we find that the error of the solutions is at most $\sim 1\%$ in the region of the parameter space that concerns the $95\%$ confidence regions that we find using the data, for all models and all statistical analyses performed in this work.

    ↳ astro-ph.COgr-qchep-phPRD(2023)·27 citations
31. 31*

    Stochastic effects on observation of ultralight bosonic dark matter

    Hiromasa Nakatsuka🇯🇵 · Soichiro Morisaki🇺🇸 · Tomohiro Fujita🇯🇵 · Jun'ya Kume🇯🇵 · Yuta Michimura🇯🇵 · Koji Nagano🇯🇵 · Ippei Obata🇩🇪

    Ultralight bosonic particles are fascinating candidates of dark matter (DM). It behaves as classical waves in our Galaxy due to its large number density. There have been various methods proposed to search for the wave-like DM, such as methods utilizing interferometric gravitational-wave detectors. Understanding the characteristics of DM signals is crucial to extract the properties of DM from data. While the DM signal is nearly monochromatic with the angular frequency of its mass, the amplitude and phase are gradually changing due to the velocity dispersion of DMs in our Galaxy halo. The stochastic amplitude and phase should be properly taken into account to accurately constrain the coupling constant of DM from data. Previous works formulated a method to obtain the upper bound on the coupling constant incorporating the stochastic effects. One of these works compared the upper bound with and without the stochastic effect in a measurement time that is much shorter than the variation time scale of the amplitude and phase. In this paper, we extend their formulation to arbitrary measurement time and evaluate the stochastic effects. Moreover, we investigate the velocity-dependent signal for dark photon DM including an uncertainly of the velocity. We demonstrate that our method accurately estimates the upper bound on the coupling constant with numerical simulations. We also estimate the expected upper bound of the coupling constant of axion DM and dark photon DM from future experiments in a semi-analytic way. The stochasticity especially affects constraints on a small mass region. Our formulation offers a generic treatment of the ultralight bosonic DM signal with the stochastic effect.

    ↳ astro-ph.COastro-ph.IMhep-exhep-ph+1PRD(2023)·35 citations
32. 32*

    GRB 201104A: A "Repetitive" Short Gamma-Ray Burst?

    Yun Wang · Lu-Yao Jiang🇨🇳 · Jia Ren🇨🇳

    Gamma-ray bursts (GRBs) are divided into short gamma-ray bursts (SGRBs) and long gamma-ray bursts (LGRBs) based on the bimodal distribution of their durations. LGRBs and SGRBs are typically characterized by different statistical characteristics. Nevertheless, there are some samples that challenge such a framework, such as GRB 060614, a long-duration burst with short-burst characteristics. Furthermore, GRBs are generally considered to be an event with no periodic or repetitive behavior, since the progenitors usually undergo destructive events, such as massive explosions or binary compact star mergers. In this work, we investigated Fermi data for possible quasiperiodic oscillations and repetitive behaviors of GRBs using timing analysis methods and report a special event GRB 201104A, which is a long-duration burst with the characteristics of an SGRB, and it exhibits a "repetitive" behavior. We propose that such a situation may arise from lensed SGRBs and attempt to verify it by Bayesian inference. In addition, we extend the spectral analysis to Bayesian inference. In spite of the existence of at least two distinct time periods with a nearly identical spectrum, there is no strong evidence that they result from a lensing GRB. Taking the gravitational-lensing scenario out of consideration, a long burst would resemble a short burst in its repetitive behavior, which presents a challenge for the current classification scheme.

    ↳ astro-ph.HEhep-phApJ(2022)·5 citations
33. 33*

    On the analytically-improved running coupling in QCD

    F. T. Brandt🇧🇷 · J. Frenkel🇧🇷 · D. G. C. McKeon🇨🇦 · G. S. S. Sakoda🇧🇷

    We examine, in the `t Hooft renormalization scheme, the analytic running coupling ${\bar{\alpha }}_t(Q^2)$ in QCD, using the two-loop $\beta$-function with positive expansion parameters ${\beta }_0$ and ${\beta }_1$. An exact integral representation is derived for this causal coupling, which is fully expressed in terms of the imaginary part of the Lambert function $W$. This integral form manifestly accounts for the universal value of the infrared limit ${\bar{\alpha }}_t(Q^2=0)=4\pi /{\beta }_0$.

    ↳ hep-thhep-phMod.Phys.Lett.A(2022)·1 citation
34. 34*

    Got plenty of nothing: cosmic voids as a probe of particle dark matter

    S. Arcari🇮🇹 · E. Pinetti🇺🇸 · N. Fornengo🇮🇹

    The search for a particle dark matter signal in terms of radiation produced by dark matter annihilation or decay has to cope with the extreme faintness of the predicted signal and the presence of masking astrophysical backgrounds. It has been shown that using the correlated information between the dark matter distribution in the Universe with the fluctuations of the cosmic radiation fields has the potential to allow setting apart a pure dark matter signal from astrophysical emissions, since spatial fluctuations in the radiation field due to astrophysical sources and dark matter emission have different features. The cross-correlation technique has been proposed and adopted for dark matter studies by looking at dark matter halos (overdensities). In this paper we extend the technique by focusing on the information on dark matter distribution offered by cosmic voids, and by looking specifically at the gamma-ray dark matter emission: we show that, while being underdense and therefore producing a reduced emission as compared to halos, nevertheless in voids the relative size of the cross-correlation signal due to decaying dark matter vs. astrophysical sources is significantly more favourable, producing signal-to-background ratios $S/B$ (even significantly) larger than 1 for decay lifetimes up to $2\times 10^{30}$ s. This is at variance with the case of halos, where $S/B$ is typically (even much) smaller than 1. We show that forthcoming galaxy surveys such as Euclid combined with future generation gamma-ray detectors with improved specifications have the ability to provide a hint of such a signal with a predicted significance up to $5.7\sigma$ for galaxies and $1.6\sigma$ for the cosmic shear. The bound on the dark matter lifetime attainable exploiting voids is predicted to improve on current bounds in a mass range for the WIMP of $25÷900$ GeV.

    ↳ astro-ph.COastro-ph.HEhep-phJCAP(2022)·16 citations
35. 35*

    Gravothermal evolution of dark matter halos with differential elastic scattering

    Daneng Yang🇺🇸 · Hai-Bo Yu🇺🇸

    We study gravothermal evolution of dark matter halos in the presence of differential self-scattering that has strong velocity and angular dependencies. We design controlled N-body simulations to model Rutherford and Moller scatterings in the halo, and follow its evolution in both core-expansion and -collapse phases. The simulations show the commonly-used transfer cross section underestimates the effects of dark matter self-interactions, but the viscosity cross section provides an accurate approximation for modeling angular-dependent dark matter scattering. We investigate thermodynamic properties of the halo, and find that the three moments of the Boltzmann equation under the fluid approximation are satisfied. We further propose a constant effective cross section, which integrates over the halo's characteristic velocity dispersion with weighting kernels motivated by kinetic theory of heat conduction. The effective cross section provides a good approximation to differential self-scattering for most of the halo evolution. It indicates that we can map astrophysical constraints on a constant self-interacting cross section to an SIDM model with velocity- and angular-dependent scatterings.

    ↳ astro-ph.COastro-ph.GAhep-phJCAP(2022)·85 citations
36. 36*

    Generalized symmetries and Noether's theorem in QFT

    Valentin Benedetti🇦🇷 · Horacio Casini🇦🇷 · Javier M. Magan🇺🇸

    We show that generalized symmetries cannot be charged under a continuous global symmetry having a Noether current. Further, only non-compact generalized symmetries can be charged under a continuous global symmetry. These results follow from a finer classification of twist operators, which naturally extends to finite group global symmetries. They unravel topological obstructions to the strong version of Noether's theorem in QFT, even if under general conditions a global symmetry can be implemented locally by twist operators (weak version). We use these results to rederive Weinberg-Witten's theorem within local QFT, generalizing it to massless particles in arbitrary dimensions and representations of the Lorentz group. Several examples with local twists but without Noether currents are described. We end up discussing the conditions for the strong version to hold, dynamical aspects of QFT's with non-compact generalized symmetries, scale vs conformal invariance in QFT, connections with the Coleman-Mandula theorem and aspects of global symmetries in quantum gravity.

    ↳ hep-thgr-qchep-phmath-ph+1JHEP(2022)·54 citations
37. 37*

    Multi-messenger High-Energy Signatures of Decaying Dark Matter and the Effect of Background Light

    Barbara Skrzypek · Marco Chianese · Carlos Argüelles Delgado

    The IceCube Neutrino Observatory at the South Pole has measured astrophysical neutrinos using through-going and starting events in the TeV to PeV energy range. The origin of these astrophysical neutrinos is still largely unresolved, and among their potential sources could be dark matter decay. Measurements of the astrophysical flux using muon neutrinos are in slight tension with starting event measurements. This tension is driven by an excess observed in the energy range of 40-200 TeV with respect to the through-going expectation. Previous works have considered the possibility that this excess may be due to heavy dark matter decay and have placed constraints using gamma-ray and neutrino data. However, these constraints are not without caveats since they rely on the modeling of the astrophysical neutrino flux and the sources of gamma-ray emission. In this work, we derive background-agnostic galactic and extragalactic constraints on decaying dark matter by considering Tibet AS${}_{\gamma }$ data, Fermi-LAT diffuse data, and the IceCube high-energy starting event sample. For the gamma-ray limits, we investigate the uncertainties on secondary emission from electromagnetic cascades during propagation arising from the unknown intensity of the extragalactic background light. We find that such uncertainties amount to a variation of up to $\sim 55\%$ in the gamma-ray limits derived with extragalactic data. Our results imply that a significant fraction of the astrophysical neutrino flux could be due to dark matter and that ruling it out depends on the assumptions on the gamma-ray and neutrino background. The latter depends on the yet unidentified sources.

    ↳ astro-ph.HEhep-exhep-phJCAP(2023)·12 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.