Tue·Nov 7, 2023Tuesday·November 7, 2023

1. 01*

   Searching for Minicharged Particles at the Energy Frontier with the MoEDAL-MAPP Experiment at the LHC

   Vasiliki A. Mitsou · Marc de Montigny · Abhinab Mukhopadhyay · Pierre-Philippe A. Ouimet · James Pinfold · Ameir Shaa · Michael Staelens

   MoEDAL's Apparatus for Penetrating Particles (MAPP) Experiment is designed to expand the search for new physics at the LHC, significantly extending the physics program of the baseline MoEDAL Experiment. The Phase-1 MAPP detector (MAPP-1) is currently undergoing installation at the LHC's UA83 gallery adjacent to the LHCb/MoEDAL region at Interaction Point 8 and will begin data-taking in early 2024. The focus of the MAPP experiment is on the quest for new feebly interacting particles$—$avatars of new physics with extremely small Standard Model couplings, such as minicharged particles (mCPs). In this study, we present the results of a comprehensive analysis of MAPP-1's sensitivity to mCPs arising in the canonical model involving the kinetic mixing of a massless dark $U(1)$ gauge field with the Standard Model hypercharge gauge field. We focus on several dominant production mechanisms of mCPs at the LHC across the mass$–$mixing parameter space of interest to MAPP: Drell$–$Yan pair production, direct decays of heavy quarkonia and light vector mesons, and single Dalitz decays of pseudoscalar mesons. The $95\%$ confidence level background-free sensitivity of MAPP-1 for mCPs produced at the LHC's Run 3 and the HL-LHC through these mechanisms, along with projected constraints on the minicharged strongly interacting dark matter window, are reported. Our results indicate that MAPP-1 exhibits sensitivity to sizable regions of unconstrained parameter space and can probe effective charges as low as $8\times 10^{-4}e$ and $6\times 10^{-4}e$ for Run 3 and the HL-LHC, respectively.

   hep-phhep-exJHEP(2024)·23 citations
2. 02*

   Thermal behavior of effective U_A(1) anomaly couplings in reflection of higher topological sectors

   G. Fejos🇭🇺 · A. Patkos🇭🇺

   Thermal behavior of effective, chiral condensate-dependent $U_A(1)$ anomaly couplings is investigated using the functional renormalization group approach in the $N_f=3$ flavor meson model. We derive flow equations for anomaly couplings that arise from instantons of higher topological charge, dependent also on the chiral condensate. These flow equations are solved numerically for the $|Q|=1,2$ topological sectors at finite temperature. Assuming that the anomaly couplings at the ultraviolet scale may also exhibit explicit temperature dependence, we calculate the thermal behavior of the effective potential. In accordance with our earlier study, [G. Fejos and A. Patkos, Phys. Rev. D{\bf 105}, 096007 (2022)], we find that for increasing temperatures, the anomalous breaking of chiral symmetry tends to strengthen toward the pseudocritical temperature ($T_C$) of chiral symmetry breaking. It is revealed that below $T_C$, around $\sim$10\% of the $U_A(1)$ breaking arises from the $|Q|=2$ topological sector. Correspondingly, a detailed analysis on the thermal behavior of the mass spectrum is also presented.

   hep-phPRD(2024)·12 citations
3. 03*

   FIRE 6.5: Feynman Integral Reduction with New Simplification Library

   Alexander V. Smirnov🇷🇺 · Mao Zeng🇬🇧

   FIRE is a program which performs integration-by-parts (IBP) reduction of Feynman integrals. Originally, the C++ version of FIRE relies on the computer algebra system Fermat by Robert Lewis to simplify rational functions. We present an upgrade of FIRE which incorporates a new library FUEL initially described in a separate publication, which enables a flexible choice of third-party computer algebra systems as simplifiers, as well as efficient communications with some of the simplifiers as C++ libraries rather than through Unix pipes. We achieve significant speedups for IBP reduction of Feynman integrals involving many kinematic variables, when using an open source backend based on FLINT newly added in this work, or the Symbolica backend developed by Ben Ruijl as a potential successor of FORM.

   hep-phComput.Phys.Commun.(2024)·82 citations
4. 04*

   Broken scale invariant unparticle physics and its prospective effects on the MuonE experiment

   Van Dung Le🇻🇳 · Duc Ninh Le🇻🇳 · Duc Truyen Le🇩🇪 · Van Cuong Le🇻🇳

   We investigate the effects of broken scale invariant unparticle at the MUonE experiment. The choice of the broken model is because the original scale-invariant model is severely suppressed by constraints from cosmology and low-energy experiments. Broken scale invariant unparticle model is categorized into four types: pseudoscalar, scalar, axial-vector, and vector unparticle. Each uparticle type is characterized by three free parameters: coupling constant $\lambda$, scaling dimension $d$, and energy scale $\mu$ at which the scale-invariance is broken. After considering all of the available constraints on the model, we find that the MUonE experiment is sensitive to (axial-)vector unparticle with $1<d<1.4$ and $1\le \mu \le 12$ GeV.

   hep-phhep-ex0 citations
5. 05*

   IBPs and differential equations in parameter space

   Daniele Artico🇩🇪 · Lorenzo Magnea🇮🇹

   We present a projective framework for the construction of Integration by Parts (IBP) identities and differential equations for Feynman integrals, working in Feynman-parameter space. This framework originates with very early results which emerged long before modern techniques for loop calculations were developed. Adapting and generalising these results to the modern language, we use simple tools of projective geometry to generate sets of IBP identities and differential equations in parameter space, with a technique applicable to any loop order. We test the viability of the method on simple diagrams at one and two loops, providing a unified viewpoint on several existing results.

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

   Light baryon spatial correlators at short distances

   Chao Han🇨🇳 · Jialu Zhang🇨🇳

   To study the light baryon light-cone distribution amplitudes (LCDAs), the spatial correlator of the light baryon has been calculated up to one-loop order in coordinate space. They reveal certain identities that do not appear in the study of mesons DAs and PDFs. Subsequently, it was renormalized using the ratio renormalization scheme involving division by a 0-momentum matrix element. Then through the matching in the coordinate space, the light baryon light-cone correlator can be extracted out from the spatial correlator. %By choosing a specific type of spatial correlator for light baryons, the LCDA is determined from first principles. These results provide insights into both the ultraviolet (UV) and infrared (IR) structures of the light baryon spatial correlator, which is valuable for further exploration in this field. Furthermore, the employed ratio scheme is an efficient and lattice-friendly renormalization approach suitable for short-distance applications. These can be used for studying the light baryon LCDAs using lattice techniques.

   hep-phPRD(2024)·16 citations
7. 07*

   Analytic solution of Balitsky-Kovchegov equation with running coupling constant using homogeneous balance method

   Yanbing Cai🇨🇳 · Xiaopeng Wang🇨🇳 · Xurong Chen🇨🇳

   In this study, we employ the homogeneous balance method to obtain an analytical solution to the Balitsky-Kovchegov equation with running coupling. We utilize two distinct prescriptions of the running coupling scale, namely the saturation scale dependent running coupling and the dipole momentum dependent running coupling. By fitting the proton structure function experimental data, we determine the free parameters in the analytical solution. The resulting ${\chi }^2/d.o.f$ values are determined to be $1.07$ and $1.43$, respectively. With these definitive solutions, we are able to predict exclusive $J/\psi$ production, and demonstrate that analytical solutions with running coupling are in excellent agreement with $J/\psi$ differential and total cross section. Furthermore, our numerical results indicate that the analytical solution of the BK equation with running coupling can provide a reliable description for both the proton structure function and exclusive vector meson production.

   hep-phPRD(2023)·7 citations
8. 08*

   Electroweak baryogenesis, dark matter, and dark CP-symmetry

   Jinghong Ma🇨🇳 · Jie Wang🇨🇳 · Lei Wang🇨🇳

   With the motivation of explaining the dark matter and achieving the electroweak baryogenesis via the spontaneous CP-violation at high temperature, we propose a complex singlet scalar ($S=\frac{\chi +i{\eta }_s}{\sqrt{2}}$) extension of the two-Higgs-doublet model respecting a discrete dark CP-symmetry: $S\to -S^{\ast }$. The dark CP-symmetry guarantees $\chi$ to be a dark matter candidate on one hand and on the other hand allows ${\eta }_s$ to have mixings with the pseudoscalars of the Higgs doublet fields, which play key roles in generating the CP-violation sources needed by the electroweak baryogenesis at high temperature. The universe undergoes multi-step phase transitions, including a strongly first-order electroweak phase transition during which the baryon number is produced. At the present temperature, the observed vacuum is produced and the CP-symmetry is restored so that the stringent electric dipole moment experimental bounds are satisfied. Considering relevant constraints, we study the simple scenario of $m_{\chi }$ around the Higgs resonance region, and find that the dark matter relic abundance and the baryon asymmetry can be simultaneously explained. Finally, we briefly discuss the gravitational wave signatures at future space-based detectors and the LHC signatures.

   hep-phastro-ph.HEhep-exPRD(2024)·4 citations
9. 09*

   Bottomonia in quark-antiquark confining potential

   Ritu Garg🇮🇳 · K.K Vishwakarma🇮🇳 · Alka Upadhyay🇮🇳

   In this paper, we comprehensively explore bottomonia mass spectra and their decay properties by solving the non-relativistic Schrodinger wave equation numerically with approximate quark-antiquark potential form. We also incorporate spin-dependent terms - spin-spin, spin-orbit, and tensor terms to remove mass degeneracy and to obtain excited states ($nS,nP,nD,nF,n=1,2,3,4,5$) mass spectra. By using Van Royen - Weisskopf formula, we investigate leptonic decay constants, di-leptonic, di-gamma, tri-gamma, di-gluon decay widths and also incorporate first-order radiative corrections. We also computed radiative transition widths, which give a better insight into the non-perturbative aspects of QCD. The present results for mass spectroscopy and decay properties are in tune with available experimental values and other theoretical predictions. Our results may provide better insight to upcoming experimental information in the near future.

   hep-phPhys.Scripta(2024)·7 citations
10. 10*

    Inflation and Reheating through an Independent Affine Connection

    Alberto Salvio🇮🇹

    This paper is based on a talk in which I discussed how a component of the dynamical affine connection, that is independent of the metric, can drive inflation in agreement with observations. This provides a geometrical origin for the inflaton. I also illustrated how the decays of this field, which has spin 0 and odd parity, into Higgs bosons can reheat the universe to a sufficiently high temperature.

    hep-phastro-ph.COgr-qchep-th2 citations
11. 11*

    The study on the multiplicity dependence of ridge behavior in $pp$ collisions at $\sqrt{s}=13$ TeV at the LHC

    Jeongseok Yoon🇰🇷 · Jin-Hee Yoon🇰🇷

    The long-range near-side ridge phenomenon in two-particle correlation is crucial for understanding the motion of partons after high-energy heavy-ion collisions. While it has been well explained by the hydrodynamic flow effect of the quark-gluon plasma (QGP) in heavy-ion collisions, the recent observation of the ridge structure in small systems has led to debates about the applicability of hydrodynamic models to explain the phenomenon since the collisions in small systems could not be sufficient to produce the medium required by the QGP matter. The Momentum Kick Model (MKM), on the other hand, explains the long-range near-side ridge phenomenon by the kinematic process; the high-momentum jet particles collide with medium partons, transfer their momentum to them (called the ``kick" process), and induce collective motion of the kicked-partons resulting in the ridge phenomenon. This MKM has successfully described the ridge structure in heavy-ion collisions at the RHIC. Furthermore, since the ridge phenomenon in small systems is prominent in high-multiplicity events, the MKM with multiplicity dependence (MKMwM) has been studied in $pp$ collisions at the LHC using a relationship between the number of kicked-partons and the multiplicity through an impact parameter. In this research, we extend the previous study with more recent experimental data-driven parameters and apply them to the new measurements that have a wider multiplicity range with $p_T$ and $\Delta \Phi$ bins at the LHC. Simultaneously, we not only provide a theoretical basis for the ridge behavior from the new measurements but also predict the ridge structure at the energies scheduled by the LHC in the upcoming Run 3 experiments.

    hep-phnucl-thNPA(2024)·0 citations
12. 12*

    Workshop summary -- Kaons@CERN 2023

    G. Anzivino🇮🇹 · S. Arguedas Cuendis🇨🇷 · V. Bernard🇫🇷 · J. Bijnens🇸🇪 · B. Bloch-Devaux🇮🇹 · M. Bordone🇨🇭 · F. Brizioli🇮🇹 · J. Brod🇺🇸 · J.M. Camalich🇪🇸 · A. Ceccucci🇨🇭 · P. Cenci🇮🇹 · N.H. Christ🇺🇸 and 51 other authors

    Kaon physics is at a turning point -- while the rare-kaon experiments NA62 and KOTO are in full swing, the end of their lifetime is approaching and the future experimental landscape needs to be defined. With HIKE, KOTO-II and LHCb-Phase-II on the table and under scrutiny, it is a very good moment in time to take stock and contemplate about the opportunities these experiments and theoretical developments provide for particle physics in the coming decade and beyond. This paper provides a compact summary of talks and discussions from the Kaons@CERN 2023 workshop.

    hep-phhep-exhep-latEPJC(2024)·40 citations
13. 13*

    Magnetic dipole moments of the ${\Omega }_c(3185{)}^0$ and ${\Omega }_c(3327{)}^0$ states from molecular perspective

    U. Özdem🇹🇷

    In this paper we study the magnetic dipole moments of the newly discovered ${\Omega }_c(3185{)}^0$ and ${\Omega }_c(3327{)}^0$, assuming that ${\Omega }_c(3185{)}^0$ and ${\Omega }_c(3327{)}^0$ are $S$-wave $D\Xi$ and $D^{\ast }\Xi$ molecular pentaquark states, respectively. Together with these states, the magnetic dipole moments of possible $D_s\Xi$, $D_s^{\ast }\Xi$, $D{\Xi }^{\ast }$, and $D_s{\Xi }^{\ast }$ pentaquark states are also studied. The magnetic dipole moments of these singly-charmed pentaquarks are estimated within the framework of the QCD light cone sum rules utilizing the photon distribution amplitudes. In the search for the properties of singly-charmed molecular pentaquark states, the results obtained for the magnetic dipole moments can be useful.

    hep-phhep-exhep-latPLB(2024)·11 citations
14. 14*

    Novelties from Flavour Physics

    Fulvia De Fazio🇮🇹

    Our present understanding of elementary particle interactions is the synergic result of developments of theoretical ideas and of experimental advances that lead to the theory known as the Standard Model of particle physics. Despite the uncountable experimental confirmations, we believe that it is not yet the ultimate theory, for a number of reasons that I will briefly recall in this lecture. My main focus will be on the role that Flavour Physics has played in development of the theory in its present formulation, as well as on the opportunities that this sector offers to discover physics beyond the Standard Model.

    hep-ph4 citations
15. 15*

    One-loop contributions for $h\to \ell \bar{\ell }\gamma$ and $e^{-}{e}^{+}\to h\gamma$ in $U(1{)}_{B-L}$ extension of the standard model

    Dzung Tri Tran (DTU)🇻🇳 · Thanh Huy Nguyen (HCMUS)🇻🇳 · Khiem Hong Phan (DTU)🇻🇳

    We present one-loop contributing for $h\to \ell \bar{\ell }\gamma$ with $\ell ={\nu }_{e,\mu ,\tau },e,\mu$ and $e^{-}{e}^{+}\to h\gamma$ in $U(1{)}_{B-L}$ extension of the standard models. In phenomenological results, the signal strengths for $h\to \ell \bar{\ell }\gamma$ at Large Hadron Collider and for $e^{-}{e}^{+}\to h\gamma$ at future Lepton Colliders are analyzed in physical parameter space for both vector and chiral $B-L$ models. We find that the contributions from neutral gauge boson $Z^{\prime }$ to the signal strengths are rather small. Consequently, the effects are hard to probe at future colliders. While the impacts of charged Higgs, CP-odd Higgs in the chiral $B-L$ model on the signal strengths are significant and can be measured with the help of the initial polarization beams at future lepton colliders.

    hep-phCPC(2024)·3 citations
16. 16*

    Progress in the Partial-Wave Analysis Methods at COMPASS

    Florian Markus Kaspar🇩🇪 · Julien Beckers🇩🇪 · Jakob Knollmüller🇩🇪

    We study the excitation spectrum of light and strange mesons in diffractive scattering. We identify different hadron resonances through partial wave analysis, which inherently relies on analysis models. Besides statistical uncertainties, the model dependence of the analysis introduces dominant systematic uncertainties. We discuss several of their sources for the ${\pi }^{-}{\pi }^{-}{\pi }^{+}$ and $K_S^0{K}^{-}$ final states and present methods to reduce them. We have developed a new approach exploiting a-priori knowledge of signal continuity over adjacent final-state-mass bins to stably fit a large pool of partial-waves to our data, allowing a clean identification of very small signals in our large data sets. For two-body final states of scalar particles, such as $K_S^0{K}^{-}$, mathematical ambiguities in the partial-wave decomposition lead to the same intensity distribution for different combinations of amplitude values. We will discuss these ambiguities and present solutions to resolve or at least reduce the number of possible solutions. Resolving these issues will allow for a complementary analysis of the $a_J$-like resonance sector in these two final states.

    hep-phhep-exEPJ Web Conf.(2024)·4 citations
17. 17*

    Charge and energy deposition in the McDIPPER framework

    Oscar Garcia-Montero🇩🇪 · Sören Schlichting🇩🇪 · Hannah Elfner🇩🇪

    In this short note we present aspects of the energy and charge deposition within the McDIPPER, a novel 3D resolved model for the initial state of ultrarelativistic Heavy-Ion collisions based on the $k_{\perp }$-factorized Color Glass Condensate hybrid approach. This framework is a initial-state Monte Carlo event generator which deposits the relevant conserved charges (energy, charge and baryon densities) both in the midrapidity and forward/backward regions of the collision. The event-by-event generator computes the gluon and (anti-) quark phase-space densities using the IP-Sat model, from where the conserved charges can be extracted directly. In this work we present the centrality and collision energy dependence for the deposited conserved quantities at midrapidity and the full event, the so-called $4\pi$ solid angle range.

    hep-phnucl-thPoS(2024)·5 citations
18. 18*

    Baryon number violation accompanied by CP-violation as a quantum tunneling effect induced by superfluid pairing interactions

    Yongliang Hao🇨🇳 · Dongdong Ni🇨🇳

    In this work, we explore a new picture of baryon number ($\mathcal{B}$) violation inspired by the formal analogies between the Brout-Englert-Higgs model and the Ginzburg-Landau model. A possible manifestation of this new picture could be the transition between a pair of neutrons and a pair of antineutrons (i.e. $nn\to \bar{n}\bar{n}$), which violates $\mathcal{B}$ by 4 units. In the presence of the superfluid pairing interactions, two neutrons can form a Cooper pair and can be modeled by a semi-classical complex scalar field, which carries two units of $\mathcal{B}$. In the presence of the $\mathcal{B}$-violating terms, the system does not possess a continuous $U(1)$ symmetry but instead it respect a discrete $Z_2$ symmetry. Before the spontaneous breaking of the $Z_2$ symmetry, the ground state (vacuum) of the neutron Cooper field and that of the antineutron Cooper field should have degenerate energy levels. After the spontaneous breaking of the $Z_2$ symmetry, the degeneracy of the ground states would be removed and a domain wall that interpolates between the two inequavalent ground states can emerge. If the vacuum energy of the neutron Cooper field is higher than that of the antineutron Cooper field, the false vacuum ($nn$) would decay into the true vacuum ($\bar{n}\bar{n}$) through a quantum tunneling process across the domain wall. Therefore, The $nn\to \bar{n}\bar{n}$ transition process can be considered as a false vacuum decay through a quantum tunneling process induced by the superfluid pairing interactions. Both the $\mathcal{B}$-violating and CP-violating effects can be quite naturally accommodated in the $nn\to \bar{n}\bar{n}$ transition process. The $\mathcal{B}$-violating process accompanied by CP-violation would open a promising avenue for exploring new physics beyond the Standard Model.

    hep-phcond-mat.supr-con0 citations
19. 19*

    One-loop correction contributions in the decoupling limit of generalized Yukawa model

    Mykyta Dmytriiev🇺🇦 · Volodymyr Skalozub🇺🇦

    We consider the generalized Yukawa model consisting of two Dirac fermions and two scalar fields. One of the scalars is assumed to be much heavier than the other particles, so it decouples at low energies. Low-energy effective Lagrangian (EL) of the model is derived. It describes the contributions of the heavy scalar into observables in the limit when this particle is decoupled. We consider the cross-sections of $s$- and $t$-channel processes, obtained within the complete model and its low-energy approximation. The contributions of the one-loop corrections in the cross-sections coming from light particles are analyzed. These are corrections to the parameters of the heavy boson and the contributions of the one-loop mixing of light and heavy scalars. We identify the ranges of Yukawa's couplings where the corrections are significant. We find that if the interaction between fermions and either light or heavy scalar is strong enough, the derived EL could not be applied for the description of the analyzed cross-sections even if the heavy scalar decouples. Implications of our results in searching for new particles beyond the Standard model are discussed.

    hep-phJournal of Physics and Electronics(2023)·0 citations
20. 20*

    Accumulating Hints for Flavour Violating Higgses at the Electroweak Scale

    Andreas Crivellin🇨🇭 · Syuhei Iguro🇩🇪

    We show that supplementing the Standard Model by only a second Higgs doublet, a combined explanation of $h\to e\tau$, $h\to \mu \tau$, $b\to s{\ell }^{+}{\ell }^{-}$, the $W$ mass and $R(D^{(\ast )})$ as well as the excess in $t\to b{H}^{+}(130\mathrm{GeV})\to b\overline{b}c$ is possible. While this requires flavour violating couplings, the stringent bounds from e.g. $\mu \to e\gamma$, $\tau \to \mu \gamma$, $B_s-{\bar{B}}_s$ mixing, $b\to s\gamma$, low mass di-jet and $pp\to H^{+}{H}^{-}\to {\tau }^{+}{\tau }^{-}\nu \bar{\nu }$ searches can be avoided. However, the model is very constrained, it inevitably predicts a shift in the SM Higgs coupling strength to tau leptons as well as a non-zero $t\to hc$ rate, as indeed preferred by recent measurements. We study three benchmark points providing such a simultaneous explanation and calculate their predictions, including collider signatures which can be tested with upcoming LHC run-3 data.

    hep-phhep-exPRD(2024)·18 citations
21. 21*

    Causality violations in simulations of large and small heavy-ion collisions

    Renata Krupczak🇩🇪 · Tiago Nunes da Silva🇧🇷 · Thiago S. Domingues🇧🇷 · Matthew Luzum🇧🇷 · Gabriel S. Denicol🇧🇷 · Fernando G. Gardim🇧🇷 · Andre V. Giannini🇧🇷 · Mauricio N. Ferreira🇪🇸 · Mauricio Hippert🇺🇸 · Jorge Noronha🇺🇸 · David D. Chinellato🇧🇷 · Jun Takahashi🇧🇷

    Heavy-ion collisions, such as Pb-Pb or p-Pb, produce extreme conditions in temperature and density that make the hadronic matter transition to a new state, called quark-gluon plasma (QGP). Simulations of heavy-ion collisions provide a way to improve our understanding of the QGP's properties. These simulations are composed of a hybrid description that results in final observables in agreement with accelerators like LHC and RHIC. However, recent works pointed out that these hydrodynamic simulations can display acausal behavior during the evolution in certain regions, indicating a deviation from a faithful representation of the underlying QCD dynamics. To pursue a better understanding of this problem and its consequences, this work simulated two different collision systems, Pb-Pb and p-Pb at $\sqrt{s_{NN}}=5.02$ TeV. In this context, our results show that causality violation, even though always present, typically occurs on a small part of the system, quantified by the total energy fraction residing in the acausal region. In addition, the acausal behavior can be reduced with changes in the pre-hydrodynamic factors and the definition of the bulk-viscous relaxation time. Since these aspects are fairly arbitrary in current simulation models, without solid guidance from the underlying theory, it is reasonable to use the disturbing presence of acausal behavior in current simulations to guide improvements towards more realistic modeling. While this work does not solve the acausality problem, it sheds more light on this issue and also proposes a way to solve this problem in simulations of heavy-ion collisions.

    ↳ nucl-thhep-phPRC(2024)·24 citations
22. 22*

    Motion of particles around a magnetically charged Euler-Heisenberg black hole with scalar hair and the Event Horizon Telescope

    Dionysios P. Theodosopoulos🇬🇷 · Thanasis Karakasis🇬🇷 · George Koutsoumbas🇬🇷 · Eleftherios Papantonopoulos🇬🇷

    We study the motion of uncharged particles and photons in the background of a magnetically charged Euler-Heisenberg (EH) black hole (BH) with scalar hair. The spacetime can be asymptotically (A)dS or flat. After investigating particle motions around the BH and the behavior of the effective potential of the particle radial motion, we determine the contribution of the BH parameters to the geodesics. Photons follow null geodesics of an effective geometry induced by the corrections of the EH non-linear electrodynamics. Thus, after determining the effective geometry, we calculate the shadow of the BH. Upon comparing the theoretically calculated BH shadow with the images of the shadows of M87* and Sgr A* obtained by the Event Horizon Telescope collaboration, we impose constraints on the BH parameters, namely the scalar hair ($\nu$), the magnetic charge ($Q_m$) and the EH parameter ($\alpha$).

    ↳ gr-qcastro-ph.HEhep-phhep-thEPJC(2024)·19 citations
23. 23*

    Quantifying the tension between cosmological models and JWST red candidate massive galaxies

    Junchao Wang🇨🇳 · Zhiqi Huang🇨🇳 · Lu Huang · Jianqi Liu🇨🇳

    We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a light-cone. The code is based on the extended Press-Schechter model and is computationally efficient, typically taking a few seconds on a personal laptop for a given set of cosmological parameters. The high efficiency of the code allows a quick estimation of the tension between cosmological models and the red candidate massive galaxies released by the James Webb Space Telescope, as well as scanning the theory space with the Markov Chain Monte Carlo method. As an example application, we use the tool to study the cosmological implication of the candidate galaxies presented in Labbé et al. (2023). The standard $\Lambda$ cold dark matter ($\Lambda$CDM) model is well consistent with the data if the star formation efficiency can reach $\sim 0.3$ at high redshift. For a low star formation efficiency $ϵ\sim 0.1$, $\Lambda$CDM model is disfavored at $\sim 2\sigma$-$3\sigma$ confidence level.

    ↳ astro-ph.COastro-ph.GAgr-qchep-ph+1Res.Astron.Astrophys.(2024)·16 citations
24. 24*

    Gravitational Wave Probe of Primordial Black Hole Origin via Superradiance

    Indra Kumar Banerjee🇮🇳 · Ujjal Kumar Dey🇮🇳

    In this article we have used stochastic gravitational wave background as a unique probe to gain insight regarding the creation mechanism of primordial black holes. We have considered the cumulative gravitational wave background which consists of the primary part coming from the creation mechanism of the primordial black holes and the secondary part coming from the different mechanisms the primordial black holes go through. We have shown that in the presence of light or ultra light scalar bosons, superradiant instability generates the secondary part of the gravitational wave background which is the most detectable. In order to show the unique features of the cumulative background, we have considered the delayed vacuum decay during a first order phase transition as the origin of primordial black holes. We have shown the dependence of the features of the cumulative background, such as the mass of the relevant light scalars, peak frequencies, etc. on the transition parameters. We have also generated the cumulative background for a few benchmark cases to further illustrate our claim.

    ↳ gr-qcastro-ph.HEhep-phJCAP(2024)·8 citations
25. 25*

    Renormalized Primordial Black Holes

    Gabriele Franciolini🇨🇭 · Andrea Ianniccari🇨🇭 · Alex Kehagias🇬🇷 · Davide Perrone🇨🇭 · Antonio Riotto🇨🇭

    The formation of primordial black holes in the early universe may happen through the collapse of large curvature perturbations generated during a non-attractor phase of inflation or through a curvaton-like dynamics after inflation. The fact that such small-scale curvature perturbation is typically non-Gaussian leads to the renormalization of composite operators built up from the smoothed density contrast and entering in the calculation of the primordial black abundance. Such renormalization causes the phenomenon of operator mixing and the appearance of an infinite tower of local, non-local and higher-derivative operators as well as to a sizable shift in the threshold for primordial black hole formation. This hints that the calculation of the primordial black hole abundance is more involved than what generally assumed.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2024)·14 citations
26. 26*

    Bayesian calibration of viscous anisotropic hydrodynamic (VAH) simulations of heavy-ion collisions

    Ulrich Heinz (Ohio State Univ.)🇺🇸 · Dananjaya Liyanage (Ohio State Univ.)🇺🇸 · Cullen Gantenberg (Ohio State Univ., Univ. of Washington)🇺🇸

    A Bayesian calibration, using experimental data from 2.76 $A$ TeV Pb-Pb collisions at the LHC, of a novel hybrid model is presented in which the usual pre-hydrodynamic and viscous relativistic fluid dynamic (vRFD) stages are replaced by a viscous anisotropic hydrodynamic (VAH) core that smoothly interpolates between the initial expansion-dominated, approximately boost-invariant longitudinally free-streaming and the subsequent collision-dominated (3+1)-dimensional standard vRFD stages. This model yields meaningful constraints for the temperature-dependent specific shear and bulk viscosities, $(\eta /s)(T)$ and $(\zeta /s)(T)$, for temperatures up to about $700$ MeV (i.e. over twice the range that could be explored with earlier models). With its best-fit model parameters the calibrated VAH model makes highly successful predictions for additional $p_T$-dependent observables for which high-quality experimental data are available that were not used for the model calibration.

    ↳ nucl-thhep-phnucl-exEPJ Web Conf.(2024)·3 citations
27. 27*

    Gravitational memory signal from neutrino self-interactions in supernova

    Soumya Bhattacharya🇮🇳 · Debanjan Bose🇮🇳 · Indranil Chakraborty🇮🇳 · Arpan Hait🇮🇳 · Subhendra Mohanty🇮🇳

    Neutrinos with large self-interactions, arising from exchange of light scalars or vectors with mass $M_{\varphi }\simeq 10\mathrm{MeV}$, can play a useful role in cosmology for structure formation and solving the Hubble tension. It has been proposed that large self-interactions of neutrinos may change the observed properties of supernova like the neutrino luminosity or the duration of the neutrino burst. In this paper, we study the gravitational wave memory signal arising from supernova neutrinos. Our results reveal that memory signal for self-interacting neutrinos are weaker than free-streaming neutrinos in the high frequency range. Implications for detecting and differentiating between such signals for planned space-borne detectors, DECIGO and BBO, are also discussed.

    ↳ gr-qcastro-ph.HEhep-phPRD(2024)·13 citations
28. 28*

    The chiral condensate at large $N$

    Claudio Bonanno🇪🇸 · Pietro Butti🇪🇸 · Margarita García Peréz🇪🇸 · Antonio González-Arroyo🇪🇸 · Ken-Ichi Ishikawa🇯🇵 · Masanori Okawa🇯🇵

    We present results for the large-$N$ limit of the chiral condensate computed from twisted reduced models. We followed a two-fold strategy, one constiting in extracting the condensate from the quark-mass dependence of the pion mass, the other consisting in extracting the condensate from the mode number of the Dirac operator.

    ↳ hep-lathep-phhep-thPoS(2024)·2 citations
29. 29*

    Spinning Primordial Black Holes from First Order Phase Transition

    Indra Kumar Banerjee🇮🇳 · Ujjal Kumar Dey🇮🇳

    We conduct a novel study to obtain the initial spin of the primordial black holes created during a first-order phase transition due to delayed false vacuum decay. Remaining within the parameter space consistent with observational bounds, we express the abundance and the initial spin of the primordial black holes as functions of the phase transition parameters. The abundance of the primordial black holes is extremely sensitive to the phase transition parameters. We also find that the initial spin weakly depends on all parameters except the transition temperature.

    ↳ gr-qchep-phJHEP(2024)·27 citations
30. 30*

    The Gravitational Wave Spectrum of Chain Inflation

    Katherine Freese🇺🇸 · Aliki Litsa🇸🇪 · Martin Wolfgang Winkler🇺🇸

    Chain inflation is an alternative to slow-roll inflation in which the inflaton tunnels along a large number of consecutive minima in its potential. In this work we perform the first comprehensive calculation of the gravitational wave spectrum of chain inflation. In contrast to slow-roll inflation the latter does not stem from quantum fluctuations of the gravitational field during inflation, but rather from the bubble collisions during the first-order phase transitions associated with vacuum tunneling. Our calculation is performed within an effective theory of chain inflation which builds on an expansion of the tunneling rate capturing most of the available model space. The effective theory can be seen as chain inflation's analogue of the slow-roll expansion in rolling models of inflation. We show that chain inflation produces a very characteristic double-peak spectrum: a faint high-frequency peak associated with the gravitational radiation emitted during inflation, and a strong low-frequency peak associated with the graceful exit from chain inflation (marking the transition to the radiation-dominated epoch). There exist very exciting prospects to test the gravitational wave signal from chain inflation at the aLIGO-aVIRGO-KAGRA network, at LISA and /or at pulsar timing array experiments. A particularly intriguing possibility we point out is that chain inflation could be the source of the stochastic gravitational wave background recently detected by NANOGrav, PPTA, EPTA and CPTA. We also show that the gravitational wave signal of chain inflation is often accompanied by running/ higher running of the scalar spectral index to be tested at future Cosmic Microwave Background experiments.

    ↳ astro-ph.COhep-phhep-thPRD(2024)·3 citations
31. 31*

    A Subtraction Scheme for Feynman Integrals

    Aaron Hillman🇺🇸

    We present a subtraction scheme for ultraviolet (UV) divergent, infrared (IR) safe scalar Feynman integrals in dimensional regularization with any number of scales. This is done by the introduction of $u$-variables, which are a suitable generalization of dihedral coordinates on the open string moduli space to Feynman integrals. The subtraction scheme furnishes subtraction terms which are products of lower loop Feynman integrals deformed by order $ϵ$ powers of $u$-variables and deformations of the degree of divergence. The result is a canonical and algorithmic prescription to express the Feynman integral as a sum of convergent integrals dressed with inverse powers of $ϵ$.

    ↳ hep-thhep-ph9 citations
32. 32*

    Bootstrapping High-Energy Observables

    Faizan Bhat🇮🇳 · Debapriyo Chowdhury🇮🇳 · Aninda Sinha🇮🇳 · Shaswat Tiwari🇺🇸 · Ahmadullah Zahed🇮🇳

    In this paper, we set up the numerical S-matrix bootstrap by using the crossing symmetric dispersion relation (CSDR) to write down Roy equations for the partial waves. As a motivation behind examining the local version of the CSDR, we derive a new, crossing symmetric, 3-channels-plus-contact-terms representation of the Virasoro-Shapiro amplitude in string theory that converges everywhere except at the poles. We then focus on gapped theories and give novel analytic and semi-analytic derivations of several bounds on low-energy data. We examine the high-energy behaviour of the experimentally measurable rho-parameter, introduced by Khuri and Kinoshita and defined as the ratio of the real to the imaginary part of the amplitude in the forward limit. Contrary to expectations, we find numerical evidence that there could be multiple changes in the sign of this ratio before it asymptotes at high energies. We compare our approach with other existing numerical methods and find agreement, with improvement in convergence.

    ↳ hep-thhep-exhep-phJHEP(2024)·22 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.