Fri·Nov 18, 2022Friday·November 18, 2022

1. 01*

   Rethinking the $P_c(4457{)}^{+}$ as the $P_{\psi }^{{\Delta }^{+}}(4457)$ isoquartet ${\bar{D}}^{\ast }{\Sigma }_c$ molecule

   Fang-Zheng Peng🇨🇳 · Mao-Jun Yan🇨🇳 · Mario Sánchez Sánchez🇫🇷 · Manuel Pavon Valderrama🇨🇳

   The nature of the $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$ pentaquarks is a fascinating theoretical question. Within the molecular picture their more usual interpretation is that of $I=\frac{1}{2}$ $\bar{D}{\Sigma }_c$ and ${\bar{D}}^{\ast }{\Sigma }_c$ bound states. Here we argue in favor of interpreting the $P_c(4457)$ pentaquark as a $I=\frac{3}{2}$ ${\bar{D}}^{\ast }{\Sigma }_c$ bound state (with spin $J=\frac{1}{2}$) instead. Owing to isospin symmetry breaking effects, with this identification the partial decay width of the $P_c(4457{)}^{+}$ into $J/\psi p$ will be of the same order of magnitude as the $P_c(4312{)}^{+}$ and $P_c(4440{)}^{+}$, in contrast with the considerably larger partial decay width in the $I=\frac{1}{2}$ scenario. In turn, this leads to a different hidden-charm molecular pentaquark spectrum, in which there are only four or five $P_{\psi }^N$ bound states instead of the usual seven, which might explain why the predicted $J=\frac{1}{2}$ and $\frac{3}{2}$ ($I=\frac{1}{2}$) ${\bar{D}}^{\ast }{\Sigma }_c^{\ast }$ molecular partners of the $P_c(4312)$ and $P_c(4440)$ have not been observed.

   hep-phhep-exnucl-thPLB(2023)·9 citations
2. 02*

   Shannon entropy of fragmentation functions and their Kullback-Leibler divergence to parton pdfs

   Guillermo Benito-Calviño🇪🇸 · Javier García-Olivares🇪🇸 · Felipe J. Llanes-Estrada🇪🇸

   The flow of information in high-energy collisions has been recently investigated by various groups: this includes the entanglement entropy of the proton becoming classical information entropy of pdfs, jet splitting affecting entropy, or the entropy distribution in hadron decays. Here we examine fragmentation functions in this context, including their entropy as probability distributions, and propose it as one convenient number to characterize progress in their extraction. We also use the Kullback-Leibler divergence to examine relations between FFs and pdfs such as that of Barone, Drago and Ma.

   hep-phEPJ Web Conf.(2022)·1 citation
3. 03*

   Shear viscosity coefficient of magnetized QCD medium near chiral phase transition

   Xueqiang Zhu🇨🇳 · Sheng-Qin Feng🇨🇳

   We study the properties of the shear viscosity coefficient of quark matter at finite temperature and chemical potential near chiral phase transition in a strong background magnetic field. A strong magnetic field induces anisotropic features, phase-space Landau-level quantization, and if the magnetic field is sufficiently strong, interferes with prominent QCD phenomena such as dynamical quark mass generation, likely affecting the quark matter transport characteristics. The modified Nambu-Jona-Lasinio (NJL) model with inverse magnetic catalysis effect by fitting the Lattice QCD (LQCD) results is used to calculate the changes of quasiparticle related thermodynamic quantities, and the shear viscosity of the system medium, which is analyzed under the relaxation time approximation. We quantify the influence of the order of chiral phase transition and the critical endpoint on dissipative phenomena in such a magnetized medium. When the magnetic field exists, the shear viscosity coefficient of the dissipative fluid system can be decomposed into five different components. In strong field limit, we make a detailed study of the dependencies of ${\eta }_2$ and ${\eta }_4$ on temperature and magnetic field for the first order phase transition and critical endpoint transition. respectively. It is found that ${\eta }_2$ and ${\eta }_4$ both decrease with magnetic field and increase with temperature, and the discontinuities of ${\eta }_2$ and ${\eta }_4$ occur at the first order phase transition point.

   hep-phPRD(2023)·10 citations
4. 04*

   Exotic states with triple charm

   M. Bayar🇹🇷 · A. Martinez Torres🇧🇷 · K. P. Khemchandani🇧🇷 · R. Molina🇪🇸 · E. Oset🇪🇸

   In this work we investigate the possibility of the formation of states from the dynamics involved in the $D^{\ast }{D}^{\ast }{D}^{\ast }$ system by considering that two $D^{\ast }$'s generate a $J^P=1^{+}$ bound state, with isospin 0, which has been predicted in an earlier theoretical work. We solve the Faddeev equations for this system within the fixed center approximation and find the existence of $J^P=0^{-}$, $1^{-}$ and $2^{-}$ states with charm $3$, isospin $1/2$, masses $\sim 6000$ MeV, which are manifestly exotic hadrons, i.e., with a multiquark inner structure.

   hep-phnucl-thEPJC(2023)·15 citations
5. 05*

   Large Primordial Fluctuations in Gravitational Waves from Phase Transitions

   Arushi Bodas🇺🇸 · Raman Sundrum🇺🇸

   It is well-known that first order phase transitions in the early universe can be a powerful source of observable stochastic gravitational wave backgrounds. Any such gravitational wave background must exhibit large-scale anisotropies at least as large as those seen in the CMB $\sim 10^{-5}$, providing a valuable new window onto the (inflationary) origins of primordial fluctuations. While significantly larger fractional anisotropies are possible (for example, in multi-field inflation) and would be easier to interpret, it has been argued that these can only be consistent with CMB bounds if the gravitational wave signal is correspondingly smaller. In this paper, we show that this argument, which relies on assuming radiation dominance of the very early universe, can be evaded if there is an era of early matter dominance of a certain robust type. This allows large gravitational wave anisotropies to be consistent with observable signals at proposed future gravitational wave detectors. Constraints from the CMB on large scales, as well as primordial black hole and mini-cluster formation on small scales, and secondary scalar-induced gravitational waves are all taken into account.

   hep-phastro-ph.COJHEP(2023)·16 citations
6. 06*

   Possible charmed-strange molecular pentaquarks in quark delocalization color screening model

   Xuejie Liu🇨🇳 · Yue Tan🇨🇳 · Xiaoyun Chen🇨🇳 · Dianyong Chen🇨🇳 · Hongxia Huang🇨🇳 · Jialun Ping🇨🇳

   Inspired by the states $T_{c\bar{s}0}^a(2900{)}^0$ and $T_{c\bar{s}0}^a(2900{)}^{++}$ reported by the LHCb Collaboration, we carry out a systematical investigation of the charm-strange pentaquark system using resonance group method in the quark delocalization color screening model. The present results predict the existence of some bound states and resonance states with support from the study of the mass spectrum and the decay properties. Both ${\Sigma }_c^{\ast }{K}^{\ast }$ with $I(J^P)=\frac{1}{2}({\frac{5}{2}}^{-})$ and $\Delta D_s^{\ast }$ with $I(J^P)=\frac{3}{2}({\frac{5}{2}}^{-})$ are bounded by channel coupling calculation. Moreover, the resonance state ${\Sigma }_c{K}^{\ast }$ with $I(J^P)=\frac{1}{2}({\frac{1}{2}}^{-})$ and $I(J^P)=\frac{1}{2}({\frac{3}{2}}^{-})$ are available in QDCSM, the masses and the total decay widths of which are ($R^{\prime }=3342\sim 3346$ MeV, ${\Gamma }_{Total}=25.5$ MeV) and ($R^{\prime }=3333$ MeV, ${\Gamma }_{Total}=3.3$ MeV), respectively. In addition, the resonance state $\Delta D_s^{\ast }$ with $I(J^P)=\frac{3}{2}({\frac{1}{2}}^{-})$ is also obtained, the mass and the decay width of this state are 3343 MeV and 0.01 MeV, respectively. These predicted new exotic states may provide new ideas for experimental searches and we sincerely expect more experimental and theoretical research to verify and understand the charm-strange pentaquark states in the future.

   hep-phPRD(2023)·9 citations
7. 07*

   Massive Gauge Theory with Quasigluon for Hot $SU(N)$: Phase Transition and Thermodynamics

   Jiang Zhu🇨🇳 · Jun Guo🇨🇳 · Zhaofeng Kang🇨🇳

   It is challenging to build a model that can correctly and unifiedly account for the deconfinement phase transition and thermodynamics of the hot $SU(N)$ pure Yang-Mills (PYM) system, for any $N$. In this article, we slightly generalize the massive PYM model to the situation with a quasigluon mass $M_g(T)$ varying with temperature, inspired by the quasigluon model. In such a framework, we can acquire an effective potential for the temporal gauge field background by perturbative calculation, rather than adding by hand. The resulting potential works well to describe the behavior of the hot PYM system for all $N$, via the single parameter $M_g(T)$. Moreover, under the assumption of unified eigenvalue distribution, the $M_g(T)$ fitted by machine learning is found to follow $N$-universality.

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

   Transition GPDs and exclusive electroproduction of $\pi -\Delta (1232)$ final states

   Peter Kroll🇩🇪 · Kornelija Passek-Kumerički🇭🇷

   We investigate exclusive electroproduction of ${\pi }^{-}{\Delta }^{++}$ within the handbag approach in which the helicity amplitudes factorize into generalized parton distributions (GPDs) and hard partonic subprocesses. We define the $p-\Delta$ transversity GPDs while the helicity non-flip GPDs are taken from the literature. For the numerical estimates of observables we utilize large-$N_C$ results in order to relate a few of the $p-\Delta$ GPDs to the proton-proton ones and neglect all other GPDs. In the calculation of the twist-2 and twist-3 subprocess amplitudes we take into account quark transverse momenta in combination with Sudakov suppressions. The partial cross sections for ${\gamma }^{\ast }p\to {\pi }^{-}{\Delta }^{++}$ are predicted in the large-$N_C$ limit.

   hep-phhep-exPRD(2023)·24 citations
9. 09*

   Off-shell effects in bound nucleons and parton distributions from ${}^1$H, ${}^2$H, ${}^3$H and ${}^3$He data

   S. I. Alekhin🇩🇪 · S. A. Kulagin🇷🇺 · R. Petti🇺🇸

   We report the results of a new global QCD analysis including deep-inelastic scattering data off ${}^1$H, ${}^2$H, ${}^3$H, and ${}^3$He targets. Nuclear corrections are treated in terms of a nuclear convolution approach with off-shell bound nucleons. The off-shell (OS) corrections responsible for the modification of the structure functions (SFs) of bound nucleons are constrained in a global fit along with the proton parton distribution functions (PDFs) and the higher-twist (HT) terms. We investigate the proton-neutron difference for the OS correction and discuss our predictions for the SF ratio $F_2^n/F_2^p$ and the corresponding PDF ratio $d/u$ in the proton, as well as their correlations with the underlying treatment of the HT terms and of the OS corrections. In particular, we find that the recent MARATHON data are consistent with equal relative OS corrections for both the proton and the neutron.

   hep-phPRD(2023)·16 citations
10. 10*

    Quantification of the hadronic CP violation contribution to the atomic EDMs

    Nodoka Yamanaka🇯🇵

    CP violating interactions are required to realize the matter abundance of our Universe. It is however known that the standard model of particle physics does not contain sufficient CP violation. The electric dipole moment (EDM) of atomic systems is a very sensitive experimental probe of CP violation beyond the standard model, and it is very actively studied in experiments. The atomic EDM has a significant sensitivity to hadronic CP violation, but its quantification has for long been obstructed by the nonperturbative physics of quantum chromodynamics. Quite recently, the contribution of the Weinberg operator (CP violating three-gluon interaction) to the atomic EDM has been analyzed, and we are almost attaining the quantification era of the CP violating hadronic interaction in the leading order of standard model effective field theory. In this proceedings contribution, we summarize the current attempt to quantify the hadronic CP violation contribution to the EDM of atoms.

    hep-phhep-exnucl-thphysics.atom-phAIP Conf.Proc.(2024)·1 citation
11. 11*

    Generalized parton distributions at zero skewness

    Hadi Hashamipour🇮🇷 · Muhammad Goharipour🇮🇷 · K. Azizi🇮🇷 · S.V. Goloskokov🇷🇺

    We present a new determination of the generalized parton distributions (GPDs) with their uncertainties at zero skewness, $\xi =0$, through a simultaneous analysis of all available experimental data of the nucleon electromagnetic form factors (FFs), nucleon charge and magnetic radii, proton axial FFs (AFFs) and wide-angle Compton scattering (WACS) cross sections for the first time, and we investigate whether there is any tension between these data. This can be considered the most comprehensive analysis of GPDs at $\xi =0$ performed so far. We show that such an analysis provides the simultaneous determination of three kinds of GPDs, namely $H^q$, ${\tilde{H}}^q$ and $E^q$, considering also the sea-quark contributions. As a result, we find that the inclusion of the WACS and AFF data at larger values of the momentum transfer squared $Q^2=-t$ can put new constraints on GPDs and change them drastically in some cases. We show that there is a considerable tension between the WACS and the proton magnetic form factor ($G_M^p$) data, especially at larger values of $-t$. However, we indicate that the results for the gravitational FF $M_2$ and the proton total angular momentum $J^p$ calculated using the extracted GPDs are in relatively good agreement with the light-cone QCD sum rules (LCSRs) and lattice QCD predictions when the sea-quark contributions are considered and both WACS and $G_M^p$ data are included in the analyses simultaneously.

    hep-phhep-exPRD(2023)·31 citations
12. 12*

    BSM scenarios with missing energy at future lepton colliders

    Tania Robens🇭🇷

    I will briefly discuss the signatures and discovery prospects of several new physics models containing dark matter candidates at future lepton colliders. In particular, I will discuss the two models that, among other signatures, lead to electroweak gauge bosons and missing energy: the Inert Doublet Model, as well as the THDMa, a two Higgs doublet model with an additional pseudoscalar that serves as a portal to the dark sector. Results are mainly based on a Snowmass Whitepaper arXiv:2203.07913

    hep-phPoS·2 citations
13. 13*

    Shedding light on thermal photon and dilepton production

    Greg Jackson🇺🇸

    Electromagnetic radiation from the quark-gluon plasma (QGP) is an important observable to be considered in heavy ion collision experiments. I will provide an update on recent advancements from perturbation theory and quenched lattice simulations. The resummed next-to-leading order (NLO) emission rate has recently been decomposed into transverse and longitudinal components, and extended to non-zero baryon chemical potential. The associated spectral function has also been tested against the Euclidean correlator, for continuum-extrapolated lattice data (at ${\mu }_{\mathrm{B}}=0$).

    hep-phEPJ Web Conf.(2022)·7 citations
14. 14*

    Definition of gravitational local spatial densities for spin-0 and spin-1/2 systems

    J. Yu. Panteleeva🇩🇪 · E. Epelbaum🇩🇪 · J. Gegelia🇩🇪 · U.-G. Meißner🇩🇪

    We work out details of defining the spatial densities corresponding to the gravitational form factors of spin-0 and spin-1/2 systems using spherically symmetric sharply localized wave packets. The expressions for the spatial densities are provided in the frames with both zero and non-zero expectation values of the momentum operator.

    hep-phhep-thnucl-thEPJC(2023)·29 citations
15. 15*

    SMEFT as a slice of HEFT's parameter space

    Alexandre Salas-Bernardez🇪🇸 · Juan J. Sanz-Cillero🇪🇸 · Felipe J. Llanes-Estrada🇪🇸 · Raquel Gomez-Ambrosio🇮🇹

    The Standard Model Effective Field Theory (SMEFT) is the parametrization chosen to interpret many modern measurements. We have recently discussed, building on the work of other groups, that its overall framework can be experimentally tested, beyond simply constraining its parameters. This is because the Higgs Effective Field Theory (HEFT) is somewhat more general, as it does not assume that the Higgs boson $h$ needs to be embedded in a complex doublet $H$ on which the Standard Model (SM) and SMEFT are built. As a result, the HEFT parameter spaces for the various relevant channels contains hypersurfaces over which one may use SMEFT to describe data. If experimental measurements of HEFT's parameters in any of those various channels yield a point outside of any of the hypersurfaces, SMEFT is falsified; meanwhile, its framework remains appropriate (in particular, as long as the SM remains compatible with data). A common necessity of the various possible tests is that processes involving different number of Higgs bosons (maintaining the number and nature of other particles unchanged) need to be contrasted.

    hep-phhep-exEPJ Web Conf.(2022)·13 citations
16. 16*

    Sensitivity of Resonant Axion Haloscopes to Quantum Electromagnetodynamics

    Michael E. Tobar🇦🇺 · Catriona A. Thomson🇦🇺 · Benjamin T. McAllister🇦🇺 · Maxim Goryachev🇦🇺 · Anton Sokolov🇬🇧 · Andreas Ringwald🇩🇪

    Recently interactions between putative axions and magnetic monopoles have been revisited by two of us [arXiv:2205.02605 [hep-ph]]. It has been shown that significant modifications to conventional axion electrodynamics arise due to these interactions, so that the axion-photon coupling parameter space is expanded from one parameter $g_{a\gamma \gamma }$ to three $(g_{a\gamma \gamma },g_{aAB},g_{aBB})$. We implement Poynting theorem to determine how to exhibit sensitivity to $g_{aAB}$ and $g_{aBB}$ using resonant haloscopes, allowing new techniques to search for axions and a possible indirect way to determine if magnetically charged matter exists.

    hep-phgr-qchep-exphysics.ins-det+1Annalen Phys.·18 citations
17. 17*

    Revisiting leptonic nonunitarity

    Daniel Aloni🇺🇸 · Avital Dery🇺🇸

    In the presence of extra neutrino states at high scales, the low-energy effective $3\times 3$ leptonic mixing matrix (LMM) is in general nonunitary. We revisit the question of what is our current knowledge of individual LMM matrix elements without assuming unitarity. We first demonstrate that a minimal set of experimental constraints suffices in bounding LMM nonunitarity parameters to the level of $\mathcal{O}(10^{-3})$, without the use of neutrino oscillation data. We then revisit oscillation results as a complementary cross-check, using different physics and different experimental techniques to probe a similar parameter space. We correct some common misconceptions in the neutrino nonunitarity literature resulting from an incautious treatment of input parameters. We find that neutrino oscillation experiments can constrain LMM nonclosure, but, contrary to claims in the literature, are completely insensitive to the overall normalization of the LMM. Thus we conclude that oscillation experiments, including the future DUNE experiment, have no power in excluding nonunitarity altogether.

    hep-phPRD(2024)·17 citations
18. 18*

    Physics of warped dimensions: discrete and continuous spectra

    Eugenio Megias · Mariano Quiros

    Using two different warped five-dimensional (5D) models with two branes along the extra dimension, we study the Green's functions and the spectral properties of some of the fields propagating in the bulk. While the first model has a discrete spectrum of Kaluza-Klein (KK) modes, the second one has a continuous spectrum above a mass gap. We also study the positivity of the spectral functions, as well as the coupling of the graviton and the radion with SM matter fields.

    hep-phhep-thEPJ Web Conf.(2022)·0 citations
19. 19*

    An Alternate Left-Right Symmetric Model with Dirac Neutrinos

    Siddharth P. Maharathy🇮🇳 · Manimala Mitra🇮🇳 · Agnivo Sarkar🇮🇳

    We study a different variant of Left-Right Symmetric Model, incorporating Dirac type neutrinos. In the absence of the bi-doublet scalars, the possibility of a universal seesaw type of mass generation mechanism for all the Standard Model charged fermions have been discussed. The model has been constructed by extending the Standard Model particle spectrum with heavy vector-like fermions as well as different scalar multiplets. We have shown that this model can generate non zero neutrino mass through loop mediated processes. The parameters which are involved in neutrino mass generation mechanism can satisfy the neutrino oscillation data for both normal and inverted hierarchy. The lightest charged Higgs plays a crucial role in neutrino mass generation mechanism and can have mass of $\mathcal{O}[\text{GeV}]$. We have systematically studied different constraints which are relevant for the charged Higgs phenomenology. In addition to that we also briefly discuss discovery prospects of the charged Higgs at different colliders.

    hep-phEPJC(2023)·10 citations
20. 20*

    Probing Left-handed Heavy Neutral Leptons in the Vector Scotogenic Model

    Paulo Areyuna C.🇨🇱 · Jilberto Zamora-Saa🇨🇱 · Alfonso R. Zerwekh🇨🇱

    In this work, we consider an extension to the Standard Model composed by a Massive Vector Doublet under SU(2)${}_L$ and a Left-handed Heavy Neutral Lepton. We study the production of these exotic leptons with the Same Flavor Opposite Sign standard lepton pair, and jets, considering Drell-Yan and Vector Boson Fusion as independent cases. We find that for the latter, the dilepton angular distribution is different enough from the background to use it as a smoking-gun for our model. Based on this fact, we establish limits on the parameter space considering previous experimental searches in this final state.

    hep-phJHEP(2024)·2 citations
21. 21*

    Baryon and meson masses in the Nambu--Jona-Lasinio model: A Bayesian approach

    Antoine Pfaff🇫🇷 · Hubert Hansen🇫🇷 · Juan M. Torres-Rincon🇪🇸 · Joerg Aichelin🇫🇷

    We investigate the capabilities of the Nambu--Jona-Lasinio model to describe and reproduce fundamental vacuum properties of Quantum Chromodynamics, notably the hadronic spectrum. Mesons are described as quark-antiquark bound states at the level of the random phase approximation of the Bethe-Salpeter equation, while baryons are characterized as quark-diquark bound states within the static approximation of the Faddeev equation. Within a Bayesian framework, we constrain the model by phenomenologically known quantities and study the implications on its parameters and predictions in vacuum, as well as the correlations between the two. We find that within our framework, the vacuum masses of mesons and baryons can be reasonably well reproduced. Scalar diquarks need to be significantly bound in order to correctly reproduce the masses of the baryon octet, therefore enforcing values of the scalar diquark coupling larger than what is suggested by the canonical Fierz values. These findings could have important implications on the phenomenology of strongly-interacting matter at high temperature and density as well as of compact star physics.

    hep-phnucl-thPRC(2023)·1 citation
22. 22*

    A lower bound on dark matter mass

    Mustafa A. Amin🇺🇸 · Mehrdad Mirbabayi🇮🇹

    We argue that there is a lower bound of order $10^{-19}$ eV on dark matter mass if it is produced after inflation via a process with finite correlation length. We rely on non-detection of free-streaming suppression and white-noise enhancement of density perturbations as the observational inputs.

    hep-phastro-ph.COPRL(2024)·62 citations
23. 23*

    Colliding poles with colliding nuclei

    Alexander Soloviev🇦🇹

    In these proceedings, I will discuss collisions of poles in the complex plane as a signature of phase transitions for theories relevant to the quark gluon plasma. I will begin with an illustrative example, namely the chiral phase transition, which can be characterized by colliding poles as a function of temperature. Then, recognizing the interplay between weak and strong coupling sectors in a typical collision, I will introduce a hybrid model with a weakly broken symmetry, which has a rich quasi-hydrodynamic phenomenological description where hydrodynamic and non-hydrodynamic poles are unified by a common dispersion relation. I will show that energy is transferred initially from the soft to the hard sector before irreversibly transferring back to the soft sector at late times, and that the model reproduces many features common to dissipative systems with a weakly broken symmetry including the k-gap.

    hep-phnucl-thEPJ Web Conf.(2022)·2 citations
24. 24*

    Constraints on Ultralight Scalar Dark Matter with Quadratic Couplings

    Thomas Bouley🇺🇸 · Philip Sørensen🇮🇹 · Tien-Tien Yu🇺🇸

    Ultralight dark matter is a compelling dark matter candidate. In this work, we examine the impact of quadratically-coupled ultralight dark matter on the predictions of Big Bang Nucleosynthesis. The presence of ultralight dark matter can modify the effective values of fundamental constants during Big Bang Nucleosynthesis, modifying the predicted abundances of the primordial elements such as Helium-4. We improve upon the existing literature in two ways: firstly, we take into account the thermal mass acquired by the ultralight dark matter due to its quadratic interactions with the Standard Model bath, which affects the cosmological evolution of the dark matter. Secondly, we treat the weak freeze-out using the full kinetic equations instead of using an instantaneous approximation. Both improvements were shown to impact the Helium-4 prediction in the context of universally-coupled dark matter in previous work. We extend these lessons to more general couplings. We show that with these modifications, Big Bang Nucleosynthesis provides strong constraints of ultralight dark matter with quadratic couplings to the Standard Model for a large range of masses as compared to other probes of this model, such as equivalence principle tests, atomic and nuclear clocks, as well as astrophysical and other cosmological probes.

    hep-phastro-ph.COJHEP(2023)·50 citations
25. 25*

    LHC Benchmark scenarios in the TRSM

    Tania Robens🇭🇷

    The TRSM is a new physics model that extends the scalar sector of the Standard Model by two additional CP even scalars. It leads to a large variety of interesting signatures, some of which have not yet been explored by the LHC experiments. I will also discuss the option to explore the hhh final state within this model.

    hep-phPoS·2 citations
26. 26*

    Resurgence of a de Sitter Glauber-Sudarshan State: Nodal Diagrams and Borel Resummation

    Suddhasattwa Brahma🇬🇧 · Keshav Dasgupta🇨🇦 · Mir-Mehedi Faruk🇨🇦 · Bohdan Kulinich🇨🇦 · Viraj Meruliya🇨🇦 · Brent Pym🇨🇦 · Radu Tatar🇬🇧

    We show that an explicit construction of a four-dimensional de Sitter space may be performed using a diagrammatic approach via nodal diagrams emanating from the path integral representation of the Glauber-Sudarshan state. Sum of these diagrams typically leads to an asymptotic series of Gevrey kind which can then be Borel resummed, thus reproducing the non-perturbative structure of the system. Our analysis shows that four-dimensional de Sitter space is not only possible in string theory overcoming the no-go and the swampland criteria -- albeit as a Glauber-Sudarshan state -- but it may also be non-perturbatively stable within a controlled temporal domain. Somewhat consistently, the Borel resummation of the Gevrey series provides strong hint towards the positivity of the cosmological constant.

    ↳ hep-thgr-qchep-phFortsch.Phys.·18 citations
27. 27*

    Colliding localized, lumpy holographic shocks with a granular nuclear structure

    Sebastian Waeber🇮🇱 · Laurence G. Yaffe🇺🇸

    We apply a recent and simple technique which speeds up the calculation of localized collisions in holography to study more realistic models of heavy ion collisions via the gauge/gravity duality. The initial data takes into account the lumpy nuclear structure of real heavy ions and the projectiles' aspect ratio mimics the Lorentz contraction of nuclei during RHIC collisions. At the hydrodynamization time of the central region of the quark gluon plasma developed during the collision, we find that most of the vorticity three vector's absolute value is deposited far away from the hydrodynamized part of the plasma. Only the relativistic corrections to the thermal vorticity in the hydrodynamized region are non-negligible. We compare the transverse flow after the collision determined in this work with previous results, without granular initial conditions and determine the proper energy density and fluid velocity in a hydrodynamized subregion of the plasma.

    ↳ hep-thgr-qchep-phnucl-thJHEP(2023)·5 citations
28. 28*

    Helicity and vorticity in heavy-ion collisions at NICA energies

    N. S. Tsegelnik🇷🇺 · E. E. Kolomeitsev🇷🇺 · V. Voronyuk🇷🇺

    Heavy-ion collisions at center-of-mass nucleon collision energies 4.5--11.5 GeV are analyzed within the PHSD transport model. Spectator nucleons are separated, and the transfer of the initial angular momentum of colliding nuclei to the fireball formed by participants is studied. The maximal angular momentum is carried by the fireball in gold-gold collisions with the impact parameter about 5 fm corresponding to centrality class 10--20\%. The obtained participant distributions were fluidized and the energy and baryon number densities, temperature, and velocity fields are obtained in the Landau frame. It is shown that the velocity field has dominantly Hubble-like transversal and longitudinal expansion with the vortical motion being only a small correction on top of it. The vorticity field is calculated and illustrated in detail. The formation of two oppositely-rotating vortex rings moving in opposite directions along the $z$ axis is demonstrated. Other characteristics of the vortical motion such as the Lamb vector field and the kinematic vorticity number are considered. The magnitude of the latter one is found to be smaller than that for the Poiseuille flow and close to the pure shear deformation corresponding to just a flattening of fluid cells. The field of hydrodynamic helicity, which is responsible for the axial vortex effect, is calculated. The separation of positive and negative helicities localized upper and lower semi-planes with respect to the reaction plane is shown. It is proved that the areas with various helicity signs can be probed by the selection of $\Lambda$ hyperons with positive and negative projections of their momenta orthogonal to the reaction plane.

    ↳ nucl-thhep-phPRC(2023)·24 citations
29. 29*

    Ending inflation with a bang: Higgs vacuum decay in $R^2$ gravity

    Andreas Mantziris🇬🇧

    According to the current experimental data, the Higgs vacuum appears to be metastable due to the development of a second lower ground state in its potential. Consequently, vacuum decay would induce the nucleation of true vacuum bubbles with catastrophic consequences for our Universe and therefore we are motivated to study possible stabilising mechanisms in the early universe. In our latest investigation (2207.00696), we studied the electroweak metastability in the context of the observationally favoured model of Starobinsky inflation. Following the motivation and techniques from our first study (2011.037633), we obtained constraints on the Higgs curvature coupling $\xi$, while embedding the SM on the modified gravity scenario $R+R^2$, which introduces Starobinsky inflation naturally. This had significant repercussions for the effective Higgs potential in the form of additional negative terms that destabilize the false vacuum. Another important aspect lay in the definition for the end of inflation, as bubble nucleation is most prominent during its very last moments. Our results dictated that these stronger lower $\xi$-bounds are very sensitive to the final moments of inflation, where spacetime deviates increasingly from de Sitter.

    ↳ astro-ph.COgr-qchep-phhep-thPoS·2 citations
30. 30*

    Composite dynamics in Sp($2N$) gauge theories

    Jong-Wan Lee🇰🇷 · Ed Bennett🇬🇧 · Deog Ki Hong🇰🇷 · Ho Hsiao🇹🇼 · C. -J. David Lin🇹🇼 · Biagio Lucini🇬🇧 · Maurizio Piai🇬🇧 · Davide Vadacchino🇬🇧

    Sp($2N$) gauge theories with fermonic matter provide an ideal laboratory to build extensions of the standard model based on novel composite dynamics. Examples include composite Higgs along with top partial compositeness and composite dark matter. Without fermions, their study also complements those based on SU($N_c$) gauge theories with which they share a common sector in the large $N_c=2N$ limit. We report on our recent progress in the numerical studies of Sp($2N$) gauge theories discretised on a four-dimensional Euclidean lattice. In particular, we present preliminary results for the low-lying mass spectra of mesons and chimera baryons in the theories with $N=2$. We also compute the topological susceptibility for various values of $N$, extrapolate the results to the large $N$ limit, and discuss certain universal properties in Yang-Mills theories.

    ↳ hep-lathep-phhep-thEPJ Web Conf.(2022)·3 citations
31. 31*

    Weinberg and few-nucleon forces

    U. van Kolck🇫🇷

    Weinberg's contributions to the power counting and derivation of few-nucleon forces in Chiral EFT are briefly recalled. Subsequent improvements are reviewed, concluding with the recent suggestion of a combinatorial enhancement.

    ↳ nucl-thhep-phJ.Phys.Conf.Ser.(2022)·0 citations
32. 32*

    Simple method for determining asymptotic states of fast neutrino-flavor conversion

    Masamichi Zaizen🇯🇵 · Hiroki Nagakura🇯🇵

    Neutrino-neutrino forward scatterings potentially induce collective neutrino oscillation in dense neutrino gases in astrophysical sites such as core-collapse supernovae (CCSN) and binary neutron star mergers (BNSM). In this paper, we present a detailed study of fast neutrino-flavor conversion (FFC), paying special attention to asymptotic states, by linear stability analysis and local simulations with a periodic boundary condition. We find that asymptotic states can be characterized by two key properties of FFC: (1) the conservation of lepton number for each flavor of neutrinos and (2) the disappearance of ELN(electron neutrino-lepton number)-XLN(heavy-leptonic one) angular crossings in the spatial- or time-averaged distributions. The system which initially has the positive (negative) ELN-XLN density reaches a flavor equipartition in the negative (positive) ELN-XLN angular directions, and the other part compensates it to preserve the conservation laws. These properties of FFCs offer an approximate scheme determining the survival probability of neutrinos in asymptotic states without solving quantum kinetic equations. We also demonstrate that the total amount of flavor conversion can vary with species-dependent neutrino distributions for identical ELN-XLN ones. Our results suggest that even shallow or narrow ELN angular crossings have the ability to drive large flavor conversion, exhibiting the need for including the effects of FFCs in the modeling of CCSN and BNSM.

    ↳ astro-ph.HEhep-phPRD(2023)·88 citations
33. 33*

    Charge diffusion in relativistic resistive second-order dissipative magnetohydrodynamics

    Ashutosh Dash🇩🇪 · Masoud Shokri🇩🇪 · Luciano Rezzolla🇩🇪 · Dirk H. Rischke🇩🇪

    We study charge diffusion in relativistic resistive second-order dissipative magnetohydrodynamics. In this theory, charge diffusion is not simply given by the standard Navier-Stokes form of Ohm's law, but by an evolution equation which ensures causality and stability. This, in turn, leads to transient effects in the charge diffusion current, the nature of which depends on the particular values of the electrical conductivity and the charge-diffusion relaxation time. The ensuing equations of motion are of so-called stiff character, which requires special care when solving them numerically. To this end, we specifically develop an implicit-explicit Runge-Kutta method for solving relativistic resistive second-order dissipative magnetohydrodynamics and subject it to various tests. We then study the system's evolution in a simplified 1+1-dimensional scenario for a heavy-ion collision, where matter and electromagnetic fields are assumed to be transversely homogeneous, and investigate the cases of an initially non-expanding fluid and a fluid initially expanding according to a Bjorken scaling flow. In the latter case, the scale invariance is broken by the ensuing self-consistent dynamics of matter and electromagnetic fields. However, the breaking becomes quantitatively important only if the electromagnetic fields are sufficiently strong. The breaking of scale invariance is larger for smaller values of the conductivity. Aspects of entropy production from charge diffusion currents and stability are also discussed.

    ↳ nucl-thhep-phphysics.flu-dynPRD(2023)·27 citations
34. 34*

    Holographic spacetime from lattice Yang-Mills theory

    Niko Jokela🇫🇮 · Arttu Pönni🇫🇮 · Kari Rummukainen🇫🇮 · Tobias Rindlisbacher🇨🇭 · Ahmed Salami🇫🇮

    Entanglement entropy is a notoriously difficult quantity to compute in strongly interacting gauge theories. Existing lattice replica methods have suffered from a severe signal-to-noise ratio problem, making high-precision studies prohibitively expensive. Our improved lattice method mitigates this situation and allows us to probe holographic predictions for the behavior of entanglement entropies in three- and four-dimensional Yang-Mills theories. We use this data for the numerical reconstruction of holographic bulk metrics.

    ↳ hep-thhep-phEPJ Web Conf.(2022)·5 citations
35. 35*

    Evolution and Possible Forms of Primordial Antimatter and Dark Matter celestial objects

    M.Yu. Khlopov🇷🇺 · O.M. Lecian🇮🇹

    The structure and evolution of Primordial Antimatter domains and Dark matter objects are analysed. Relativistic low-density antimatter domains are described. The Relativistic FRW perfect-fluid solution is found for the characterization of i) ultra-high density antimatter domains, ii) high-density antimatter domains, and iii) dense anti-matter domains. The possible sub-domains structures is analyzed. The structures evolved to the time of galaxy formation are outlined. Comparison is given with other primordial celestial objects. The features of antistars are outlined. In the case of WIMP dark matter clumps, the mechanisms of their survival to the present time are discussed. The cosmological features of neutrino clumping due to fifth force are examined.

    ↳ gr-qcastro-ph.COhep-ph4 citations
36. 36*

    Multi-Representation Dynamics of SU(4) Composite Higgs Models: Chiral Limit and Spectral Reconstructions

    Luigi Del Debbio🇬🇧 · Alessandro Lupo🇬🇧 · Marco Panero🇮🇹 · Nazario Tantalo🇮🇹

    We present a lattice study of the $SU(4)$ gauge theory with two Dirac fermions in the fundamental and two in the two-index antisymmetric representation, a model close to a theory of partial compositeness. Focus of this work are the methodologies behind the computation of the spectrum and the extrapolation of the chiral point for a theory with matter in multiple representations. While being still technical, this study provides important steps towards a non-perturbative understanding of the spectrum of theories of partial compositeness, which present a richer dynamics compared to single-representation theories. The multi-representation features are studied first in perturbation theory, and then non-perturbatively by adopting a dual outlook on lattice data through a joint analysis of time-momentum correlation functions and smeared spectral densities.

    ↳ hep-lathep-phEPJC(2023)·38 citations
37. 37*

    Exposing the threshold structure of loop integrals

    Zeno Capatti🇨🇭

    The understanding of the physical laws determining the infrared behaviour of amplitudes is a longstanding and topical problem. In this paper, we show that energy conservation alone implies strong constraints on the threshold singularity structure of Feynman diagrams. In particular, we show that it implies a representation of loop integrals in terms of Fourier transforms of non-simplicial convex cones. We then engineer a triangulation that has a direct diagrammatic interpretation in terms of a straightforward edge-contraction operation. We use it to develop an algorithmic procedure that performs the Fourier integrations in closed form, yielding the novel Cross-Free Family three-dimensional representation of loop integrals. Contrary to the TOPT and LTD representations, its singularity structure is entirely and elegantly expressed in terms of the graph-theoretic notions of connectedness and crossing. These results can be used to classify infrared-finite scattering theories, numerically evaluate loop integrals and to simplify threshold regularisation procedures.

    ↳ hep-thhep-phPRD(2023)·24 citations
38. 38*

    Mind the gap: The discrepancy between simulation and reality drives interpretations of the Galactic Center Excess

    Sascha Caron🇳🇱 · Christopher Eckner🇫🇷 · Luc Hendriks🇳🇱 · Gu{\dh}laugur Jóhannesson🇮🇸 · Roberto Ruiz de Austri🇪🇸 · Gabrijela Zaharijas🇸🇮

    The Galactic Center Excess (GCE) in GeV gamma rays has been debated for over a decade, with the possibility that it might be due to dark matter annihilation or undetected point sources such as millisecond pulsars (MSPs). This study investigates how the gamma-ray emission model ($\gamma$EM) used in Galactic center analyses affects the interpretation of the GCE's nature. To address this issue, we construct an ultra-fast and powerful inference pipeline based on convolutional Deep Ensemble Networks. We explore the two main competing hypotheses for the GCE using a set of $\gamma$EMs with increasing parametric freedom. We calculate the fractional contribution ($f_{\mathrm{src}}$) of a dim population of MSPs to the total luminosity of the GCE and analyze its dependence on the complexity of the $\gamma$EM. For the simplest $\gamma$EM, we obtain $f_{\mathrm{src}}=0.10\pm 0.07$, while the most complex model yields $f_{\mathrm{src}}=0.79\pm \mathrm{0.24.}$ In conclusion, we find that the statement about the nature of the GCE (dark matter or not) strongly depends on the assumed $\gamma$EM. The quoted results for $f_{\mathrm{src}}$ do not account for the additional uncertainty arising from the fact that the observed gamma-ray sky is out-of-distribution concerning the investigated $\gamma$EM iterations. We quantify the reality gap between our $\gamma$EMs using deep-learning-based One-Class Deep Support Vector Data Description networks, revealing that all employed $\gamma$EMs have gaps to reality. Our study casts doubt on the validity of previous conclusions regarding the GCE and dark matter, and underscores the urgent need to account for the reality gap and consider previously overlooked ''out of domain'' uncertainties in future interpretations.

    ↳ astro-ph.HEhep-phJCAP(2023)·13 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.