HEP Phenomenology·hep-ph

Thu·Oct 29, 2020Thursday·October 29, 2020

31 papers—18 primary·13 cross-listed·reconstructed*

01*
Astrophysical constraints on non-standard coherent neutrino-nucleus scattering
Anna M. Suliga🇩🇰 · Irene Tamborra (Niels Bohr Institute)🇩🇰
The exciting possibility of detecting supernova, solar, and atmospheric neutrinos with coherent neutrino-nucleus scattering detectors is within reach, opening up new avenues to probe New Physics. We explore the possibility of constraining non-standard coherent neutrino-nucleus scattering through astrophysical neutrinos. Sensitivity bounds on the mass and coupling of the new mediator are obtained by inspecting the modifications induced by the new interaction on the recoil rate observable in the upcoming RES-NOVA and DARWIN facilities. Under the assumption of optimal background tagging, the detection of neutrinos from a galactic supernova burst, or one-year exposure to solar and atmospheric neutrinos, will place the most stringent bounds for mediator couplings $g ≳ 1 0^{- 5}$ and mediator masses between 1 and 100 MeV. A similar, but slightly improved, potential to COHERENT will be provided for larger mediator masses. In particular, RES-NOVA and DARWIN may potentially provide one order of magnitude tighter constraints than XENON1T on the mediator coupling. Non-standard coherent neutrino-nucleus scattering may also force neutrinos to be trapped in the supernova core; this argument allows to probe the region of the parameter space with $g ≳ 1 0^{- 4}$ , which is currently excluded by other coherent neutrino-nucleus scattering facilities or other astrophysical and terrestrial constraints.
hep-phastro-ph.HEPRD(2021)·43 citations
02*
Probing the $H^{\pm} W^{\mp} Z$ interaction at the high energy upgrade of the LHC
Amit Adhikary🇮🇳 · Nabarun Chakrabarty🇮🇳 · Indrani Chakraborty🇮🇳 · Jayita Lahiri🇮🇳
An $H^{\pm} W^{\mp} Z$ interaction at the tree level is common feature of new physics models that feature scalar triplets. In this study, we aim to probe the strength of the aforementioned interaction in a model-agnostic fashion at the futuristic 27 TeV proton-proton collider. We assume that the $H^{\pm}$ couples dominantly to ( $W^{\pm}, Z$ ) and ( $t, b$ ). We specifically study the processes that involve the $H^{\pm} W^{\mp} Z$ vertex at the production level, that is, $pp \to H^{\pm} j j$ and $pp \to Z H^{\pm}$ . Moreover, we look into both $H^{\pm} \to W^{\pm} Z, t b$ decays for either production process. Our investigations reveal that the $H^{\pm} j j$ production process has a greater reach compared to $Z H^{\pm}$ . Moreover, the discovery potential of a charged Higgs improves markedly with respect to the earlier studies corresponding to lower centre-of-mass energies. Finally, we recast our results in the context of the popular Georgi-Machacek model.
hep-phhep-exEPJC(2021)·14 citations
03*
Anomaly Detection for Physics Analysis and Less than Supervised Learning
Benjamin Nachman🇺🇸
Modern machine learning tools offer exciting possibilities to qualitatively change the paradigm for new particle searches. In particular, new methods can broaden the search program by gaining sensitivity to unforeseen scenarios by learning directly from data. There has been a significant growth in new ideas and they are just starting to be applied to experimental data. This chapter introduces these new anomaly detection methods, which range from fully supervised algorithms to unsupervised, and include weakly supervised methods.
hep-phhep-exphysics.data-an28 citations
04*
Coulomb-nuclear interference in proton-proton scattering: Reply to a comment of V.\ Petrov
Loyal Durand🇺🇸 · Phuoc Ha🇺🇸
We show that the remarks of V.\ Petrov in the preceding Comment are misdirected in the region of very small momentum transfers relevant to the study of Coulomb-nuclear interference in proton-proton scattering, and clarify the connection between our results and those of Cahn and of Kundrát and Lokajiček which he cites.
hep-ph0 citations
05*
Multi-messenger cosmology of new physics
Maxim Yu. Khlopov🇷🇺
The observational evidence for the inflationary cosmology with baryosynthesis and dark matter/energy can be viewed as the messenger for new physics, which governed the Universe origin, evolution and structure. To specify the physics beyond the Standard model (BSM), underlying the modern cosmological paradigm additional model dependent messengers are proposed, involving multi-component and composite dark matter, meta-stable particles, primordial black holes and antimatter domains in baryon asymmetrical Universe.
hep-phastro-ph.COgr-qchep-thJ.Phys.Conf.Ser.(2020)·5 citations
06*
Gravitino thermal production revisited
Helmut Eberl🇦🇹 · Ioannis D. Gialamas🇬🇷 · Vassilis C. Spanos🇬🇷
We calculate the gravitino production rate, computing its one-loop thermal self-energy. Gravitino production processes that do not result through thermal cuts of its self-energy, have been identified and taken into account. Correcting analytical errors and numerical approximations in the previous calculations, we present our result. This deviates from the latest estimation by almost 10%. More importantly, we provide a convenient formula, for calculating the gravitino production rate and its thermal abundance, as a function of the reheating temperature of the Universe.
hep-phastro-ph.COhep-thPRD(2021)·60 citations
07*
Thermodynamic properties of the trigonometric Rosen-Morse potential and applications to a quantum gas of mesons
Aram Bahroz Brzo🇮🇶 · David Alvarez-Castillo🇵🇱
In this study we work out thermodynamic functions for a quantum gas of mesons described as color-electric charge dipoles. They refer to a particular parametrization of the trigonometric Rosen-Morse potential which allows to be transformed to a perturbation of free quantum motion on the three-dimensional hyper-sphere, $S^{3}$ , a manifold that can host only charge-neutral systems, the charge dipoles being the configuration of the minimal number of constituents. To the amount charge neutrality manifests itself as an important aspect of the color confinement in the theory of strong interaction, the Quantum Chromodynamics, we expect our findings to be of interest to the evaluation of temperature phenomena in the physics of hadrons and in particular in a quantum gas of color charge dipoles as are the mesons. The results are illustrated for $f_{0}$ and $J / ψ$ mesons.
hep-phastro-ph.HEnucl-thquant-phMod.Phys.Lett.A(2021)·5 citations
08*
Lipatov's QCD high energy effective action: past and future
Martin Hentschinski🇲🇽
In this contribution we briefly review some aspects of Lipatov's gauge invariant QCD high energy effective action. The high energy effective provides a field theory framework to systematically factorize QCD scattering amplitudes and related theories in the limit of high center of mass energies. After a short review of the underlying concepts, we address the question how the high energy effective action can be used for actual calculations. As an explicit example we review the derivation of the gluon Regge trajectory up to 2 loop. We then review two topics of current interest: automatic amplitude generation of high energy effective action amplitudes and a discussion of the relation between the so-called Color-Glass-Condensate framework and the high energy effective action.
hep-ph7 citations
09*
The exact WKB for cosmological particle production
Seishi Enomoto🇨🇳 · Tomohiro Matsuda🇯🇵
The Bogoliubov transformation in cosmological particle production can be explained by the Stokes phenomena of the corresponding ordinary differential equation. The calculation becomes very simple as far as the solution is described by a special function. Otherwise, the calculation requires more tactics, where the Exact WKB (EWKB) may be a powerful tool. Using the EWKB, we discuss cosmological particle production focusing on the effect of more general interaction and classical scattering. The classical scattering appears when the corresponding scattering problem of the Schrödinger equation develops classical turning points on the trajectory. The higher process of fermionic preheating is also discussed using the Landau-Zener model.
hep-phastro-ph.COhep-thJHEP(2021)·44 citations
10*
The unitarity of a spontaneously broken SU(2) theory using unitary-gauge diagrams
Jochem Kip🇳🇱 · Ronald Kleiss🇳🇱
A spontaneously broken SU(2) theory is the simplest generalization of the Abelian Higgs model, containing three equally massive vector bosons and a single Higgs scalar. A strictly diagrammatic proof is presented of the tree-level unitarity of this model in the unitary gauge, i.e. employing only physical fields. A new Ward-like identity is used to show that the high-energy behaviour of all amplitudes cannot be more than quadratic; the use of generating functions for all off-shell amplitudes then leads to the unitarity proof.
hep-phhep-th0 citations
11*
$X_{J} (2900)$ states in a hot hadronic medium
Luciano M. Abreu🇧🇷
In this work we investigate the hadronic effects on the $X_{J = 0, 1} (2900)$ states in heavy-ion collisions. We make use of Effective Lagrangians to estimate the cross sections and their thermal averages of the processes $X_{J} π \to D ˉ^{*} K, K^{*} D ˉ$ , as well as those of the corresponding inverse processes, considering also the possibility of different isospin assignments ( $I = 0, 1$ ). We complete the analysis by solving the rate equation to follow the time evolution of the $X_{J} (2900)$ multiplicities and determine how they are affected by the considered reactions during the expansion of the hadronic matter. We also perform a comparison of the $X_{J} (2900)$ abundances considering them as hadronic molecular states ( $J = 0$ as a $S$ -wave and $J = 1$ as a $P$ -wave) and tetraquark states at kinetic freeze-out.
hep-phPRD(2021)·26 citations
12*
Investigation of $Ξ_{c}^{0}$ in a chiral quark model
Xiaohuang Hu🇨🇳 · Yue Tan🇨🇳 · Jialun Ping
Recently, three new states of $Ξ_{c}^{0}$ were observed in the invariant mass spectrum of $Λ_{c}^{+} K^{-}$ by LHCb collaboration. In this work, we use a chiral quark model to investigate these three exited states with the help of Gaussian expansion method both in three-quark structure and in five-quark structure with all possible quantum numbers $I J^{P} = \frac{1}{2} (\frac{1}{2})^{-}$ , $\frac{1}{2} (\frac{3}{2})^{-}$ , $\frac{1}{2} (\frac{5}{2})^{-}$ , $\frac{3}{2} (\frac{1}{2})^{-}$ , $\frac{3}{2} (\frac{3}{2})^{-}$ and $\frac{3}{2} (\frac{5}{2})^{-}$ . The calculations shows that the 2 $S$ states of $Ξ_{c}^{'} (2579)^{0}$ and $Ξ_{c} (2645)^{0}$ are comparable to experimental results; In addition, the resonance states of five-quark configuration are possible candidates of these new states with negative parity by using the real scaling method and their decay width are also given.
hep-phEPJC(2021)·11 citations
13*
Probing extended Higgs sectors by the synergy between direct searches at the LHC and precision tests at future lepton colliders
Masashi Aiko🇯🇵 · Shinya Kanemura🇯🇵 · Mariko Kikuchi🇯🇵 · Kentarou Mawatari🇯🇵 · Kodai Sakurai🇩🇪 · Kei Yagyu🇯🇵
We discuss a possibility that the parameter space of the two Higgs doublet model is significantly narrowed down by considering the synergy between direct searches for additional Higgs bosons at the LHC and its luminosity upgraded operation and precision measurements of the Higgs boson properties at future electron-positron colliders such as the International Linear Collider. We show that, in the case where the coupling constants of the discovered Higgs boson are slightly different from the predicted values in the standard model, most of the parameter space is explored by the direct searches of extra Higgs bosons, in particular for the decays of the extra Higgs bosons into the discovered Higgs boson, and also by the theoretical arguments such as perturbative unitarity and vacuum stability. This can be done because there appears an upper limit on the mass of the extra Higgs bosons as long as the deviation exists in the Higgs boson coupling. We also show that in the alignment limit where all the Higgs boson couplings take the standard model like values most of the parameter space cannot be excluded because most of the Higgs to Higgs decays are suppressed and also there is no upper limit on the masses from the theoretical arguments.
hep-phNPB(2021)·40 citations
14*
Vacuum expectation value renormalization in the Standard Model and beyond
Vytautas Dūdėnas🇱🇹 · Maximilian Löschner🇩🇪
We show how the renormalization constant of the Higgs vacuum expectation value, fixed by a tadpole condition, is responsible for gauge dependences in various definitions of parameters in the $R_{ξ}$ -gauge. Then we show the relationship of this renormalization constant to the Fleischer-Jegerlehner (FJ) scheme, which is used to avoid these gauge dependences. In this way, we also present a viewpoint on the FJ-scheme complementary to the ones already existing in the literature. Additionally, we compare and discuss different approaches to the renormalization of tadpoles by identifying the similarities and relations between them. The relationship to the Higgs background field renormalization is also discussed.
hep-phPRD(2021)·11 citations
15*
Flavoured Neutrinoless Double Beta Decay
Lukas Graf🇩🇪 · Sudip Jana🇩🇪 · Manfred Lindner🇩🇪 · Werner Rodejohann🇩🇪 · Xun-Jie Xu🇩🇪
We discuss a mechanism of neutrinoless double beta decay, where neutrinos of different flavours come into play. This is realized by effective flavour-violating scalar interactions. As one consequence, we find that within the normal mass ordering the neutrino effective mass may no longer vanish due to contributions from other flavours. We evaluate the necessary nuclear matrix elements, consider the interference between the standard diagram and the new scalar one, and analyze a UV-complete model that realizes the scalar interaction. Tests of the complete model are possible at colliders and future neutrino experiments. Our scenario represents an alternative mechanism for neutrinoless double beta decay, where nevertheless lepton number violation resides only in Majorana mass terms of light neutrinos.
hep-phhep-exnucl-exPRD(2021)·9 citations
16*
Higher Spin Dark Matter
Stephon Alexander🇺🇸 · Leah Jenks🇺🇸 · Evan McDonough🇺🇸
Little is known about dark matter beyond the fact that it does not interact with the standard model or itself, or else does so incredibly weakly. A natural candidate, given the history of no-go theorems against their interactions, are higher spin fields. Here we develop the scenario of higher spin (spin $s > 2$ ) dark matter. We show that the gravitational production of superheavy bosonic higher spin fields during inflation can provide all the dark matter we observe today. We consider the observable signatures, and find a potential characteristic signature of bosonic higher spin dark matter in directional direct detection; we find that there are distinct spin-dependent contributions to the double differential recoil rate, which complement the oscillatory imprint of higher spin fields in the cosmic microwave background. We consider the extension to higher spin fermions and supersymmetric higher spins.
hep-phastro-ph.COgr-qchep-thPLB(2021)·39 citations
17*
A Closer Look at CP-Violating Higgs Portal Dark Matter as a Candidate for the GCE
Katherine Fraser🇺🇸 · Aditya Parikh🇺🇸 · Weishuang Linda Xu🇺🇸
A statistically significant excess of gamma rays has been reported and robustly confirmed in the Galactic Center over the past decade. Large local dark matter densities suggest that this Galactic Center Excess (GCE) may be attributable to new physics, and indeed it has been shown that this signal is well-modelled by annihilations dominantly into $b b ˉ$ with a WIMP-scale cross section. In this paper, we consider Majorana dark matter annihilating through a Higgs portal as a candidate source for this signal, where a large CP-violation in the Higgs coupling may serve to severely suppress scattering rates. In particular, we explore the phenomenology of two minimal UV completions, a singlet-doublet model and a doublet-triplet model, and map out the available parameter space which can give a viable signal while respecting current experimental constraints.
hep-phastro-ph.COJHEP(2021)·18 citations
18*
The physics case for an electron-muon collider
Meng Lu🇨🇳 · Andrew Michael Levin🇨🇳 · Congqiao Li🇨🇳 · Antonios Agapitos🇨🇳 · Qiang Li🇨🇳 · Fanqiang Meng🇨🇳 · Sitian Qian🇨🇳 · Jie Xiao🇨🇳 · Tianyi Yang🇨🇳
An electron-muon collider with an asymmetric collision profile targeting multi-ab $^{- 1}$ integrated luminosity is proposed. This novel collider, operating at collisions energies of e.g. 20-200 GeV, 50-1000 GeV and 100-3000 GeV, would be able to probe charged lepton flavor violation and measure Higgs boson properties precisely. The collision of an electron and muon beam leads to less physics background compared with either an electron-electron or a muon-muon collider, since electron-muon interactions proceed mostly through higher order vector boson fusion and vector boson scattering processes. The asymmetric collision profile results in collision products that are boosted towards the electron beam side, which can be exploited to reduce beam-induced background from the muon beam to a large extent. With this in mind, one can imagine a lepton collider complex, starting from colliding order 10 GeV electron and muon beams for the first time in history and to probe charged lepton flavor violation, then to be upgraded to a collider with 50-100 GeV electron and 1-3 TeV muon beams to measure Higgs properties and search for new physics, and finally to be transformed to a TeV scale muon muon collider. The cost should vary from order 100 millions to a few billion dollars, corresponding to different stages, which make the funding situation more practical.
hep-phhep-exAdv.High Energy Phys.(2021)·39 citations
19*
Dominance of $γ$ - $γ$ electron-positron pair creation in a plasma driven by high-intensity lasers
Y. He🇺🇸 · T. G. Blackburn🇸🇪 · T. Toncian🇩🇪 · A. V. Arefiev🇺🇸
Creation of electrons and positrons from light alone is a basic prediction of quantum electrodynamics, but yet to be observed. Here we show that it is possible to create $> 1 0^{8}$ positrons by dual laser irradiation of a structured plasma target, at intensities of $2 \times 1 0^{22} W cm^{- 2}$ . In contrast to previous work, the pair creation is primarily driven by the linear Breit-Wheeler process ( $γ γ \to e^{+} e^{-}$ ), not the nonlinear process assumed to be dominant at high intensity, because of the high density of $γ$ rays emitted inside the target. The favorable scaling with laser intensity of the linear process prompts reconsideration of its neglect in simulation studies, but also permits positron jet formation at intensities that are already experimentally feasible. Simulations show that the positrons, confined by a quasistatic plasma magnetic field, may be accelerated by the lasers to energies $> 200$ MeV.
↳ physics.plasm-phhep-ph1 citation
20*
Non-local quark models for description of dense matter in the cores of neutron stars
German Malfatti🇦🇷
This thesis work focuses on studying the possible existence of phase transitions in the immediate compact remnants of core collapse supernova, neutron stars, and the theoretical models that describe the interior of dense matter. Specifically, we are interested in analyzing the feasibility of a transition from hadronic matter to quark matter in the cores of these objects. For the phase transition we will use two different formalisms: the Maxwell formalism or abrupt phase transition and the Gibbs formalisms or mixed phase transition. For the description of hadronic matter, we will use different parametrizations of the relativistic mean field model with density-dependent coupling constants. For the description of quark matter we will use an effective nonlocal Nambu Jona-Lasinio model of three flavors with vector interactions, in which we will include the possibility of formation of diquarks to model a superconducting phase of color in $S U (3)$ . Phase diagrams and equations of state of quark matter at finite temperature are presented, and the influence of that type of matter on observables associated with neutron stars is investigated. The simplified thermal evolution of compact stars during their formation is studied, from their state of proto-neutron stars to that of cold neutron stars, and the results obtained are compared with recent astrophysical observations. The results obtained indicate that the occurrence of quark matter in the nuclei of these stars remains a promising possibility. The fact that the use of more realistic models for the description of the dense matter in these objects indicates the presence of quark matter inside neutron stars, could be an answer to the question of the behavior of that kind of matter and the determination of its corresponding equation of state.
↳ nucl-thastro-ph.HEhep-ph2 citations
21*
Effective Cross Section of Fuzzy Dark Matter Halos
Dongsu Bak🇰🇷 · Jae-Weon Lee🇰🇷 · Sangnam Park🇰🇷
We numerically study the movement of two colliding fuzzy dark matter solitons without explicit self-interaction and find the effective cross section of dissipative change in velocity. The cross section turns out to be inversely proportional to the velocity cubed, and we present its analytic interpretation. Using the result we roughly estimate spatial offsets during head-on collisions of two fuzzy dark matter halos, which can be related to the spatial offsets between stars and dark matter in collisions of some galaxy clusters. We also show that the gravitational cooling plays an important role during the collisions.
↳ astro-ph.COastro-ph.GAhep-phhep-thJ.Korean Phys.Soc.(2021)·5 citations
22*
Wilson loops for triangular contours with circular edges
Harald Dorn🇩🇪
We calculate Wilson loops in lowest order of perturbation theory for triangular contours whose edges are circular arcs. Based on a suitable disentanglement of the relations between metrical and conformal parameters of the contours, the result fits perfectly in the structure predicted by the anomalous conformal Ward identity. The conformal remainder function depends in the generic 4D case on three cusp and on three torsion angles. The restrictions on these angles imposed by the closing of the contour are discussed in detail and also for cases in 3D and 2D.
↳ hep-thhep-phmath-phmath.MPJ.Phys.A(2021)·3 citations
23*
Correlated Dirac Eigenvalues and Axial Anomaly in Chiral Symmetric QCD
H.-T. Ding🇨🇳 · S.-T. Li🇨🇳 · Swagato Mukherjee🇺🇸 · A. Tomiya🇺🇸 · X.-D. Wang🇨🇳 · Y. Zhang🇨🇳
We introduce novel relations between the derivatives [ $\partial^{n} ρ (λ, m_{l}) / \partial m_{l}^{n}$ ] of the Dirac eigenvalue spectrum [ $ρ (λ, m_{l})$ ] with respect to the light sea quark mass ( $m_{l}$ ) and the $(n + 1)$ -point correlations among the eigenvalues ( $λ$ ) of the massless Dirac operator. Using these relations we present lattice QCD results for $\partial^{n} ρ (λ, m_{l}) / \partial m_{l}^{n}$ ( $n = 1, 2, 3$ ) for $m_{l}$ corresponding to pion masses $m_{π} = 160 - 55$ MeV, and at a temperature of about 1.6 times the chiral phase transition temperature. Calculations were carried out using (2+1) flavors of highly improved staggered quarks with the physical value of strange quark mass, three lattice spacings $a = 0.12, 0.08, 0.06$ fm, and lattices having aspect ratios $4 - 9$ . We find that $ρ (λ \to 0, m_{l})$ develops a peaked structure. This peaked structure arises due to non-Poisson correlations within the infrared part of the Dirac eigenvalue spectrum, becomes sharper as $a \to 0$ , and its amplitude is proportional to $m_{l}^{2}$ . We demonstrate that this $ρ (λ \to 0, m_{l})$ is responsible for the manifestations of axial anomaly in two-point correlation functions of light scalar and pseudoscalar mesons. After continuum and chiral extrapolations we find that axial anomaly remains manifested in two-point correlation functions of scalar and pseudoscalar mesons in the chiral limit.
↳ hep-lathep-phhep-thnucl-thPRL(2021)·96 citations
24*
Identified particle spectra in Pb-Pb, Xe-Xe and p-Pb collisions with Tsallis blast-wave model
G.R. Che🇨🇳 · J.B. Gu🇨🇳 · W.C. Zhang🇨🇳 · H. Zheng🇨🇳
We investigate the identified hadrons transverse momentum ( $p_{T}$ ) spectra in Pb-Pb (Pb-Pb, Xe-Xe, p-Pb) collisions at $s_{NN} =$ 2.76 (5.02, 5.44, 5.02) TeV in the framework of Tsallis-blast wave (TBW) model with a linear transverse velocity profile and with a constant velocity profile. In this model, the Tsallis temperature ( $T$ ), the average radial flow velocity ( $⟨ β ⟩$ ) and the degree of non-equilibrium ( $q$ ) of the system are common for all hadrons when a combined fit is performed to the $p_{T}$ spectra of different particles at a given centrality. It is found that the model can describe the particle spectra well up to 3 GeV/c. For both profiles, the transverse flow velocity decreases from central to peripheral collisions while the non-extensive parameter $q$ exhibits the opposite behavior, indicating a more rapid expansion and less off-equilibrium of the system in more central collisions. Moreover, we observe that in central collisions $⟨ β ⟩$ and $q$ ( $T$ ) from the fit with the linear profile are smaller (is slightly larger) than those (that) with the constant profile, while in peripheral collisions $⟨ β ⟩$ , $T$ and $q$ from the former are compatible with those from the latter. We also derived and discussed the relation between the Tsallis temperature and the thermal temperature. In addition, to check whether a scenario of an early freeze-out of strange particles at the LHC exists, the particle spectra are investigated by grouping them into strange and non-strange hadrons. The combined fit gives an insight on the degree of non-equilibrium, the radial flow and the Tsallis temperature of the system at the kinetic decoupling. It provides a comparison between the results at different energies in the same collision system and the results in different collision systems at the same or similar energy.
↳ nucl-thhep-phJ.Phys.G(2021)·41 citations
25*
Multi-field inflation from a higher derivative N = 1 Supergravity model
G. A. Diamandis🇬🇷 · B. C. Georgalas🇬🇷 · K. Kaskavelis🇬🇷 · G. Pavlopoulos🇬🇷
We study the cosmological evolution of a N = 1 supergravity model, dual to a higher derivative supergravity model coupled to scalar fields so that in the Einstein frame the model is ghost free. We find that this model admit slow roll inflationary solutions showing essentially two-field inflation. The cosmological parameters calculated for this model lie in acceptable range with corrections of the order lnN/N, N being the number of e-foldings, compared to the Starobinsky inflation model.
↳ hep-thhep-ph1 citation
26*
A transverse momentum differential global analysis of Heavy Ion Collisions
Govert Nijs🇺🇸 · Wilke van der Schee🇨🇭 · Umut Gürsoy🇳🇱 · Raimond Snellings🇳🇱
The understanding of heavy ion collisions and its quark-gluon plasma formation requires a complicated interplay of rich physics in a wealth of experimental data. In this work we compare for identified particles the transverse momentum dependence of both the yields and the anisotropic flow coefficients for both PbPb and $p$ Pb collisions. We do this in a global model fit including a free streaming prehydrodynamic phase with variable velocity $v_{fs}$ , thereby widening the scope of initial conditions. During the hydrodynamic phase we vary three second order transport coefficients. The free streaming velocity has a preference slightly below the speed of light. In this extended model the bulk viscosity is small and even consistent with zero.
↳ nucl-thhep-phnucl-exPRL(2021)·205 citations
27*
Seeding Supermassive Black Holes with Self-Interacting Dark Matter: A Unified Scenario with Baryons
Wei-Xiang Feng🇺🇸 · Hai-Bo Yu🇺🇸 · Yi-Ming Zhong🇺🇸
Observations show that supermassive black holes (SMBHs) with a mass of $\sim 1 0^{9} M_{⊙}$ exist when the Universe is just $6%$ of its current age. We propose a scenario where a self-interacting dark matter halo experiences gravothermal instability and its central region collapses into a seed black hole. The presence of baryons in protogalaxies could significantly accelerate the gravothermal evolution of the halo and shorten collapse timescales. The central halo could dissipate its angular momentum remnant via viscosity induced by the self-interactions. The host halo must be on high tails of density fluctuations, implying that high- $z$ SMBHs are expected to be rare in this scenario. We further derive conditions for triggering general relativistic instability of the collapsed region. Our results indicate that self-interacting dark matter can provide a unified explanation for diverse dark matter distributions in galaxies today and the origin of SMBHs at redshifts $z \sim 6 - 7$ .
↳ astro-ph.COastro-ph.GAhep-phApJL(2021)·98 citations
28*
Bayesian analysis of heavy ion collisions with the heavy ion computational framework Trajectum
Govert Nijs🇺🇸 · Wilke van der Schee🇨🇭 · Umut Gürsoy🇳🇱 · Raimond Snellings🇳🇱
We introduce a model for heavy ion collisions named Trajectum, which includes an expanded initial stage with a variable free streaming velocity $v_{fs}$ and a hydrodynamic stage with three varying second order transport coefficients. We describe how to obtain a Gaussian Emulator for this 20-parameter model and show results for key observables. This emulator can be used to obtain Bayesian posterior estimates on the parameters, which we test by an elaborate closure test as well as a convergence study. Lastly, we employ the optimal values of the parameters found in [1] to perform a detailed comparison to experimental data from PbPb and $p$ Pb collisions. This includes both observables that have been used to obtain these values as well as wider transverse momentum ranges and new observables such as correlations of event-plane angles.
↳ nucl-thhep-phnucl-exPRC(2021)·295 citations
29*
Non-thermal neutrinos created by shock acceleration in successful and failed core-collapse supernova
Hiroki Nagakura🇺🇸 · Kenta Hotokezaka🇯🇵
We present a comprehensive study of neutrino shock acceleration in core-collapse supernova (CCSN). The leading players are heavy leptonic neutrinos, $ν_{μ}$ and $ν_{τ}$ ; the former and latter potentially gain the energy up to $\sim 100$ MeV and $\sim 200$ MeV, respectively, through the shock acceleration. Demonstrating the neutrino shock acceleration by Monte Carlo neutrino transport, we make a statement that it commonly occurs in the early post bounce phase ( $≲ 50$ ms after bounce) for all massive stellar collapse experiencing nuclear bounce and would reoccur in the late phase ( $≳ 100$ ms) for failed CCSNe. This opens up a new possibility to detect high energy neutrinos by terrestrial detectors from Galactic CCSNe; hence, we estimate the event counts for Hyper(Super)-Kamiokande, DUNE, and JUNO. We find that the event count with the energy of $≳ 80$ MeV is a few orders of magnitude higher than that of the thermal neutrinos regardless of the detectors, and muon production may also happen in these detectors by $ν_{μ}$ with the energy of $≳ 100$ MeV. The neutrino signals provide a precious information on deciphering the inner dynamics of CCSN and placing a constraint on the physics of neutrino oscillation; indeed, the detection of the high energy neutrinos through charged current reaction channels will be a smoking gun evidence of neutrino flavor conversion.
↳ astro-ph.HEhep-exhep-phnucl-ex+1MNRAS(2021)·17 citations
30*
Propagation effects in the FRB 20121102A spectra
D.G. Levkov🇷🇺 · A.G. Panin🇷🇺 · I.I. Tkachev🇷🇺
We advance theoretical methods for studying propagation effects in the Fast Radio Burst (FRB) spectra. We derive their autocorrelation function in the model with diffractive lensing and strong Kolmogorov-type scintillations and analytically obtain the spectra lensed on different plasma density profiles. With these tools, we reanalyze the highest frequency 4-8 GHz data of Gajjar et al. (2018) for the repeating FRB 20121102A (FRB 121102). In the data we discover, first, a remarkable spectral structure of almost equidistant peaks separated by $95 \pm 16$ MHz. We suggest that it can originate from diffractive lensing of the FRB signals on a compact gravitating object of mass $1 0^{- 4} M_{⊙}$ or on a plasma underdensity near the source. Second, the spectra include erratic interstellar, presumably Milky Way scintillations. We extract their decorrelation bandwidth $3.3 \pm 0.6$ MHz at reference frequency 6 GHz. The third feature is a GHz-scale pattern which, as we find, linearly drifts with time and presumably represents a wide-band propagation effect, e.g. GHz-scale scintillations. Fourth, many spectra are dominated by a narrow peak at 7.1 GHz. We suggest that it can be caused by a propagation through a plasma lens, e.g., in the host galaxy. Fifth, separating the propagation effects, we give strong arguments that the intrinsic progenitor spectrum has narrow GHz bandwidth and variable central frequency. This confirms expectations from the previous observations. We discuss alternative interpretations of the above spectral features.
↳ astro-ph.HEastro-ph.COhep-phApJ(2022)·9 citations
31*
Observation of a new interaction between a single spin and a moving mass
Xing Rong🇨🇳 · Man Jiao🇨🇳 · Maosen Guo🇨🇳 · Diguang Wu🇨🇳 · Jiangfeng Du🇨🇳
Searching for physics beyond the standard model is crucial for understanding the mystery of the universe, such as the dark matter. We utilized a single spin in a diamond as a sensor to explore the spin-dependent interactions mediated by the axion-like particles, which are well motivated by dark matter candidates. We recorded non-zero magnetic fields exerted on the single electron spin from a moving mass. The strength of the magnetic field is proportional to the velocity of the moving mass. The dependency of the magnetic field on the distance between the spin and the moving mass has been experimentally characterized. We analyzed the possible sources of this magnetic signal, and our results provide highly suggestive of the existence of a new spin-dependent interaction. Our work opens a door for investigating the physics beyond the standard model in laboratory.
↳ quant-phhep-exhep-ph6 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.