Thu·May 12, 2022Thursday·May 12, 2022

1. 01*

   Non-Unitary Mixing Matrices in Neutrino and Vector-like Quark Models

   Pedro M. F. Pereira🇵🇹

   This work analyses a class of extensions of the Standard Model through the lens of a novel exact parameterisation. This parameterisation is specially suitable to the analysis of extensions of the Standard Model with non-unitary mixing matrices, like models with vector-like fermions or right-handed neutrinos. The usefulness of this parameterisation is motivated with two example models: A) Standard Model with the addition of $n_u$ up and $n_d$ down singlet vector-like quarks and B) Standard Model with the addition of $n_R$ right-handed neutrinos.

   hep-phPoS(2022)·1 citation
2. 02*

   Precision boson-jet azimuthal decorrelation at hadron colliders

   Yang-Ting Chien🇺🇸 · Rudi Rahn🇳🇱 · Ding Yu Shao🇨🇳 · Wouter J. Waalewijn🇳🇱 · Bin Wu🇪🇸

   The azimuthal angular decorrelation of a vector boson and jet is sensitive to QCD radiation, and can be used to probe the quark-gluon plasma in heavy-ion collisions. By using a recoil-free jet definition, the sensitivity to contamination from soft radiation on the measurement is reduced, and the complication of non-global logarithms is eliminated from our theoretical calculation. Specifically we will consider the $p_T^n$ recombination scheme, as well as the $n\to \infty$ limit, known as the winner-take-all scheme. These jet definitions also significantly simplify the calculation for a track-based measurement, which is preferred due to its superior angular resolution. We present a detailed discussion of the factorization in Soft-Collinear Effective Theory, revealing why the transverse momentum ${\vec{q}}_T$ is more complicated than the azimuthal angle. We show that potential glauber contributions do not spoil our factorization formalism, at least up to and including order ${\alpha }_s^3$. The resummation is carried out using the renormalization group, and all necessary ingredients are collected or calculated. We conclude with a detailed phenomenological study, finding an enhanced matching correction for high jet $p_T$ due to the electroweak collinear enhancement of a boson emission off di-jets. We also compare with the Pythia event generator, finding that our observable is very robust to hadronization and the underlying event.

   hep-phnucl-thJHEP(2023)·38 citations
3. 03*

   Elaborating the Ultimate Fate of Fast Collective Neutrino Flavor Oscillations

   Soumya Bhattacharyya (TIFR Mumbai)🇮🇳 · Basudeb Dasgupta (TIFR Mumbai)🇮🇳

   Dense clouds of neutrinos and antineutrinos can exhibit fast collective flavor oscillations. Previously, in Phys. Rev. Lett. 126 (2021) 061302, we proposed that such flavor oscillations lead to depolarization, i.e., an irreversible mixing of the flavors, whose extent depends on the initial momentum distributions of the different flavors. In this paper, we elaborate and extend this proposal, and compare it with related results in the literature. We present an accurate analytical estimate for the lower resting point of the fast flavor pendulum and underline the relaxation mechanisms, i.e., transverse relaxation, multipole cascade, and mixing of flavor-waves, that cause it to settle down. We estimate the extent of depolarization, its dependence on momentum and net lepton asymmetry, and its generalization to three flavors. Finally, we prescribe approximate analytical recipes for the depolarized distributions and fluxes that can be used in supernova/nucleosynthesis simulations and supernova neutrino phenomenology.

   hep-phastro-ph.COastro-ph.GAastro-ph.HE+1PRD(2022)·64 citations
4. 04*

   Discriminating between Lorentz violation and non-standard interactions using core-passing atmospheric neutrinos at INO-ICAL

   Sadashiv Sahoo🇮🇳 · Anil Kumar🇮🇳 · Sanjib Kumar Agarwalla🇮🇳 · Amol Dighe🇮🇳

   Precision measurements of neutrino oscillation parameters have provided a tremendous boost to the search for sub-leading effects due to several beyond the Standard Model scenarios in neutrino oscillation experiments. Among these, two of the well-studied scenarios are Lorentz violation (LV) and non-standard interactions (NSI), both of which can affect neutrino oscillations significantly. We point out that, at a long-baseline experiment where the neutrino oscillation probabilities can be well-approximated by using the line-averaged constant matter density, the effects of these two scenarios can mimic each other. This would allow the limits obtained at such an experiment on one of the above scenarios to be directly translated to the limits on the other scenario. However, for the same reason, it would be difficult to distinguish between LV and NSI at a long-baseline experiment. We show that the observations of atmospheric neutrinos, which travel a wide range of baselines and may encounter sharp density changes at the core-mantle boundary, can break this degeneracy. We observe that identifying neutrinos and antineutrinos separately, as can be done at INO-ICAL, can enhance the capability of atmospheric neutrino experiments to discriminate between these two new-physics scenarios.

   hep-phhep-exphysics.ins-detPLB(2023)·18 citations
5. 05*

   Convergence of the nucleation rate for first-order phase transitions

   Andreas Ekstedt🇸🇪

   This paper investigates the importance of radiative corrections for first-order phase transitions, with particular focus on the bubble-nucleation rate. All calculations are done with a strict power-counting, and observables are consistently calculated at every order. This ensures that physical quantities are gauge and renormalization-scale invariant. Furthermore, to avoid large logarithms at high-temperatures, an effective three-dimensional theory is used. This effective theory automatically incorporates higher-order thermal masses. The results of this paper indicate that sub-leading corrections to the rate can be large. This is partly because radiative corrections are enhanced for large bubbles. To illustrate the calculations, three models are considered: a real-scalar model, a radiative-barrier model, and a model with an effective dimension $6$ operator. Relevant observables are calculated for each model, and the reliability of perturbation theory is discussed.

   hep-phhep-thPRD(2022)·32 citations
6. 06*

   One-dimensional complex potentials for quarkonia in a quark-gluon plasma

   Roland Katz🇫🇷 · Stéphane Delorme🇫🇷 · Pol-Bernard Gossiaux🇫🇷

   Master equations of the Lindblad type have recently been derived to describe the dynamics of quarkonium states in the quark-gluon plasma. Because their full resolution in three dimensions is very challenging, the equations are often reduced to one dimension. The main ingredient of these equations is the complex potential that describes the binding of the heavy quark-antiquark pairs and their interactions with the medium. In this work, we propose a one-dimensional complex potential parameterized to reproduce at best two key properties -- the temperature-dependent masses of the eigenstates and their decay widths -- of a three-dimensional lattice QCD inspired potential. Their spectral decompositions are calculated to check their compatibility with the positivity of the master equations.

   hep-phnucl-thEPJA(2022)·11 citations
7. 07*

   Investigating the Isospin Property of $T_{cc}^{+}$ from its Dalitz Plot Distribution

   Jun Shi🇨🇳 · Enke Wang🇨🇳 · Qian Wang🇨🇳

   Recently, LHCb observed a double-charmed tetraquark candidate $T_{cc}^{+}$ and claimed its isospin to be zero due to the absence of $T_{cc}^{++}$. However, the absence of the $T_{cc}^{++}$ in LHCb may be due to their low production in $pp$ collisions, thus the isospin of $T_{cc}^{+}$ still needs to be clarified. We propose an efficient way to investigate the isospin property of $T_{cc}^{+}$ from the Dalitz plot distribution of $T_{cc}^{+}\to D^{+}{D}^0{\pi }^0$. This method can also be applied to other exotic candidates.

   hep-phhep-exPRD(2022)·7 citations
8. 08*

   Re-evaluation of the isoscalar mixing angle within selected mesonic nonets

   Xue-Chao Feng🇨🇳 · Ke-Wei Wei🇨🇳

   Based on the relations from the meson-meson mass mixing matrix, the mixing angles of isoscalar state have been re-evaluated via mass relations and latest experimental results. The results in the present work are compared with the values from different theoretical models, meanwhile, the quarkonia content of isoscalar state are presented. In order to check the validity of analysis, some predictions on the decays of the isoscalar state are presented. These predictions may be useful for the phenomenological analysis for meson nonet in future experiments.

   hep-phActa Phys.Polon.B(2022)·0 citations
9. 09*

   Where Neutrino Decoherence Lies

   Emilio Ciuffoli🇨🇳 · Jarah Evslin🇨🇳

   Recently, several studies of neutrino oscillations in the vacuum have not found the decoherence long expected from the separation of wave packets of neutrinos in different mass eigenstates. We show that such decoherence will, on the other hand, be present in a treatment including any mechanism which leads to a dependence of the final state on both the neutrino's emission and absorption time. Our demonstration is in the 3+1d $V-A$ model, however the details of this model lead to an overall factor which does not affect our conclusions. This allows us to consider a simpler model. There we show that if the positions of the final state particles are measured, or equivalently entangled with the environment, then decoherence will damp neutrino oscillations. We also show that wave packet spreading can cause the decoherence to eventually saturate, without completely suppressing the oscillations.

   hep-phEPJC(2022)·4 citations
10. 10*

    Explicit computation of jet functions in coordinate space

    Alexandre Salas-Bernárdez🇪🇸

    I review the main results leading to Factorization of QCD amplitudes in momentum space and, in view of the analogue results in coordinate space, the one-loop jet function in coordinate space is computed and Landau's equations for the Abelian radiative corrections to it are studied. Furthermore, two of these radiative corrections are reduced in quadrature.

    hep-phhep-thNPB(2022)·3 citations
11. 11*

    The axion-photon mixing in non-linear electrodynamic scenarios

    J. M. A. Paixão🇧🇷 · L. P. R. Ospedal🇧🇷 · M. J. Neves🇧🇷 · J. A. Helayël-Neto🇧🇷

    In this contribution, we re-assess some aspects of axionic electrodynamics by coupling non-linear electromagnetic effects to axion physics. We present a number of motivations to justify the coupling of the axion to the photon in terms of a general non-linear extension of the electromagnetic sector. Our emphasis in the paper relies on the investigation of the constitutive permittivity and permeability tensors, for which the axion contributes by introducing dependence on the frequency and wave vector of the propagating radiation. Also, we point out how the axion mass and the axion-photon-photon coupling constant contribute to a dispersive behavior of the electromagnetic waves, in contrast to what happens in the case of non-linear extensions, when effective refractive indices appear which depend only on the direction of the propagation with respect to the external fields. The axion changes this picture by yielding refractive indices with dependence on the wavelength. We apply our results to the special case of the (non-birefringent) Born-Infeld Electrodynamics and we show that it becomes birefringent whenever the axion is coupled. The paper is supplemented by an Appendix, where we follow our own path to approach the recent discussion on a controversy in the definition of the Poynting vector of axionic electrodynamics.

    hep-phhep-thJHEP(2022)·17 citations
12. 12*

    Factorial cumulants from short-range correlations and global baryon number conservation

    Michał Barej🇵🇱 · Adam Bzdak🇵🇱

    We calculate the baryon factorial cumulants assuming arbitrary short-range correlations and the global baryon number conservation. The general factorial cumulant generating function is derived. Various relations between factorial cumulants subjected to baryon number conservation and the factorial cumulants without this constraint are presented. We observe that for $n$-th factorial cumulant, the short-range correlations of more than $n$ particles are suppressed with the increasing number of particles. The recently published [1] relations between the cumulants in a finite acceptance with global baryon conservation and the grand-canonical susceptibilities are reproduced.

    hep-phhep-exnucl-exnucl-thPRC(2022)·9 citations
13. 13*

    Strange quark mass effect in $B_s\to \gamma \gamma ,\gamma \ell \bar{\ell }$ decays

    Dong-Hao Li🇨🇳 · Lei-Yi Li🇨🇳 · Cai-Dian Lü🇨🇳 · Yue-Long Shen🇨🇳

    In this paper we investigate the next-to-leading power contribution to the $B_s\to \gamma \gamma$ and $B_s\to \gamma \ell \bar{\ell }$ decays from the strange quark mass effect with the dispersion approach which is QCD inspired and more predictive. We have presented the analytic expression of the quark mass contribution in the $B_s\to \gamma \gamma$ and $B_s\to \gamma \ell \bar{\ell }$ decays, together with a new term that is missed in the previous study. The numerical results of the strange quark mass contribution to the $B_s\to \gamma \gamma$ decay is about 6% relative to the total branching ratio, while it is relatively small in the $B_s\to \gamma \ell \bar{\ell }$ decay due to the large resonance contribuiton

    hep-phPRD(2022)·3 citations
14. 14*

    Mono-$\gamma$ Production of a Vector Dark Matter at Future $e^{+}{e}^{-}$ Collider

    Kai Ma🇨🇳

    Associated production of a dark particle and a photon, represented as a mono-$\gamma$ event, is a promising channel to probe particle contents and dynamics in the dark sector. In this paper we study properties of the mono-$\gamma$ production of a vector dark matter at future $e^{+}{e}^{-}$ colliders. The photon-like and Pauli operators, as well as triple gauge bosons interactions involving the dark matter, are considered in the framework of Effective Field Theory. We show that, comparing to the Pauli operator, the triple gauge bosons couplings are much more interesting at high energy collider. Beam polarization effects are also analyzed, and we show that the experimental sensitivities can not be enhanced significantly because of the smaller luminosity.

    hep-phCPC(2022)·7 citations
15. 15*

    Muon $g-2$ Anomaly from Vector-like Leptons in a 2-Higgs-doublet + Scalar Singlet Model

    Tim Brune🇩🇪 · Thomas W. Kephart🇺🇸 · Heinrich Päs🇩🇪

    We revisit an economical model for the $g-2$ anomaly featuring a vector-like charged fermion, a scalar doublet and a scalar singlet in the light of new results from Fermilab. The phenomenological implications for lepton-flavor universality, Higgs decays, and charged lepton-flavor violating decays are discussed in detail.

    hep-phEPJC(2024)·9 citations
16. 16*

    Global fit on coloured scalars including the last W-boson mass measurement

    V. Miralles🇮🇹 · O. Eberhardt🇪🇸 · H. Gisbert🇩🇪 · A. Pich🇪🇸 · J. Ruiz-Vidal🇪🇸

    We consider a simple extension of the electroweak theory, incorporating one $SU(2{)}_L$ doublet of colour-octet scalars with Yukawa couplings satisfying the principle of minimal flavour violation. Using the HEPfit package, we perform a global fit to the available data, including all relevant theoretical constraints, and extract the current bounds on the model parameters. We also calculate the contributions of the additional coloured scalars to the electric dipole moment of the neutron and set limits on its parameter space using the current experimental information. Finally, we study the effect that the last measurement of the $W$-boson mass has in our fit and show how the colour-octet scalar extension struggles to accommodate the new measurement.

    hep-ph3 citations
17. 17*

    Tau depolarization at very high energies for neutrino telescopes

    Carlos A. Argüelles🇺🇸 · Diksha Garg🇺🇸 · Sameer Patel🇺🇸 · Mary Hall Reno🇺🇸 · Ibrahim Safa🇺🇸

    The neutrino interaction length scales with energy, and becomes comparable to Earth's diameter above 10's of TeV energies. Over terrestrial distances, the tau's short lifetime leads to an energetic regenerated tau neutrino flux, tau neutrino to tau to tau neutrino, within the Earth. The next generation of neutrino experiments aim to detect ultra-high energy neutrinos. Many of them rely on detecting either the regenerated tau neutrino, or a tau decay shower. Both of these signatures can be affected by the polarization of the tau through the energy distribution of the secondary particles produced from the tau's decay. While taus produced in weak interactions are nearly 100 percent polarized, it is expected that taus experience some depolarization due to electromagnetic interactions in the Earth. In this paper, for the first time we quantify the depolarization of taus in electromagnetic energy loss. We find that tau depolarization has only small effects on the final energy of tau neutrinos or taus produced by high energy tau neutrinos incident on the Earth. Tau depolarization can be directly implemented in Monte Carlo simulations such as nuPyProp and TauRunner.

    hep-phastro-ph.HEPRD(2022)·12 citations
18. 18*

    Probing Top-quark Operators with Precision Electroweak Measurements

    Yiming Liu🇨🇳 · Yuhao Wang🇨🇳 · Cen Zhang🇨🇳 · Lei Zhang🇨🇳 · Jiayin Gu🇨🇳

    In the Standard Model Effective Field Theory (SMEFT), operators involving the top quark are generally difficult to probe, and can generate sizable loop contributions to the electroweak precision observables, measured by past and future lepton colliders. Could the high precision of the electroweak measurements compensate the loop suppression and provide competitive reaches on these operators? Would the inclusion of these contributions introduce too many additional parameters for a meaningful global electroweak analysis to be done? In this paper, we perform a detailed phenomenological study to address these two important questions. Focusing on eight dimension-6 operators that generate anomalous couplings between the electroweak gauge bosons and the third-generation quarks, we calculate their one loop contributions to the $e^{+}{e}^{-}\to f\bar{f}$ processes both on and off the Z-pole and the $e^{-}{e}^{+}\to WW$ process. A global analysis is performed with these eight operators and the ones that contribute to the above processes at tree level, using the measurements at LEP, SLC and several low energy experiments. We find that, while the current electroweak precision measurements are sensitive to the one-loop effects of the top-quark operators, it is difficult to separate them from the operators that contribute at the tree level, making a global analysis rather challenging. Under more assumptions, competitive reaches could be obtained in a global fit. Another important finding of our study is that the two operators that generate dipole interactions of the bottom quark have significant impacts in the Z-pole measurements and should not be omitted. We also discuss the implication of the recently reported W-boson mass measurement at CDF to our results. Finally, we estimate the reaches of future lepton colliders in probing the top-quark operators with precision electroweak measurements.

    hep-phCPC(2022)·22 citations
19. 19*

    First indirect detection constraints on axions in the Solar basin

    William DeRocco🇺🇸 · Shalma Wegsman🇺🇸 · Brian Grefenstette🇺🇸 · Junwu Huang🇨🇦 · Ken Van Tilburg🇺🇸

    Axions with masses of order keV can be produced in great abundance within the Solar core. The majority of Sun-produced axions escape to infinity, but a small fraction of the flux is produced with speeds below the escape velocity. Over time, this process populates a basin of slow-moving axions trapped on bound orbits. These axions can decay to two photons, yielding an observable signature. We place the first limits on this solar basin of axions using recent quiescent solar observations made by the NuSTAR X-ray telescope. We compare three different methodologies for setting constraints, and obtain world-leading limits for axions with masses between 5 and 30 keV, in some cases improving on stellar cooling bounds by more than an order of magnitude in coupling.

    hep-phastro-ph.SRPRL(2022)·44 citations
20. 20*

    Sudakov Shoulder Resummation for Thrust and Heavy Jet Mass

    Arindam Bhattacharya🇺🇸 · Matthew D. Schwartz🇺🇸 · Xiaoyuan Zhang🇺🇸

    When the allowed range of an observable grows order-by-order in perturbation theory, its perturbative expansion can have discontinuities (as in the $C$ parameter) or discontinuities in its derivatives (as in thrust or heavy jet mass) called Sudakov shoulders. We explore the origin of these logarithms using both perturbation theory and effective field theory. We show that for thrust and heavy jet mass, the logarithms arise from kinematic configurations with narrow jets and deduce the next-to-leading logarithmic series. The left-shoulder logarithms in heavy jet mass ($\rho$) of the form $r{\alpha }_s^n{\ln }^{2n}r$ with $r=\frac{1}{3}-\rho$ are particularly dangerous, because they invalidate fixed order perturbation theory in regions traditionally used to extract ${\alpha }_s$. Although the factorization formula shows there are no non-global logarithms, we find Landau-pole like singularities in the resummed distribution associated with the cusp anomalous dimension, and that power corrections are exceptionally important.

    hep-phhep-thPRD(2022)·21 citations
21. 21*

    Naturalness: A Snowmass White Paper

    Nathaniel Craig🇺🇸

    We assess the state of naturalness in high-energy physics and summarize recent approaches to the three major naturalness problems: the cosmological constant problem, the electroweak hierarchy problem, and the strong CP problem.

    hep-phhep-thEPJC(2023)·122 citations
22. 22*

    Constraining the Milky Way's Pulsar Population with the Cosmic-Ray Positron Fraction

    Olivia Meredith Bitter🇺🇸 · Dan Hooper🇺🇸

    Observations of the TeV halos associated with nearby pulsars indicate that these objects inject significant fluxes of very high-energy electron-positrons pairs into the interstellar medium (ISM), thereby likely providing the dominant contribution to the cosmic-ray positron flux. In this paper, we use the cosmic-ray positron fraction as measured by the AMS-02 Collaboration to constrain the characteristics of the local pulsar population. For reasonable model parameters, we find that we can obtain good agreement with the measured positron fraction up to energies of $E_e\sim 300\mathrm{GeV}$. At higher energies, the positron fraction is dominated by a small number of pulsars, making it difficult to reliably predict the shape of the expected positron fraction. The low-energy positron spectrum supports the conclusion that pulsars typically transfer approximately $\eta \sim 5-20\%$ of their total spindown power into the production of very high-energy electron-positron pairs, producing a spectrum of such particles with a hard spectral index, $\alpha \sim 1.5-1.7$. Such pulsars typically spindown on a timescale on the order of $\tau \sim 10^4\mathrm{years}$. Our best fits were obtained for models in which the radio and gamma-ray beams from pulsars are detectable to 28% and 62% of surrounding observers, respectively.

    ↳ astro-ph.HEastro-ph.COastro-ph.GAhep-phJCAP(2022)·10 citations
23. 23*

    Electroweak Penguin Decays of $b$-Flavoured Hadrons

    Ulrik Egede🇦🇺 · Shohei Nishida🇯🇵 · Mitesh Patel🇬🇧 · Marie-Hélène Schune🇫🇷

    In the past decade, electroweak penguin decays have provided a number of precision measurements, turning into one of the most competitive ways to search for New Physics that describe beyond the Standard Model phenomena. An overview of the measurements made at the $B$ factories and hadron colliders are given and the experimental methods are presented. Experimental measurements required to provide further insight into present indications of New Physics are discussed.

    ↳ hep-exhep-phAnn.Rev.Nucl.Part.Sci.(2022)·10 citations
24. 24*

    Spontaneous Symmetry Breaking without classical fields: a Functional Renormalization Group approach

    A. Jakovac🇭🇺 · P. Mati🇭🇺 · P. Posfay🇭🇺

    We propose an approach to describe Spontaneous Symmetry Breaking (SSB) that does not rely on the order parameter dependent free energy (Landau theory). We use the Functional Renormalization Group (FRG) evolution of the explicitly broken theory, using a truncation scheme that is compatible with the Ward identities. To represent the symmetry breaking, we propose to use the "Ward ratio" which is zero in the symmetric phase and unity in the broken phase. In this approach a unified scale evolution of the effective potential is applicable in both phases. It is peculiar that the scale evolution is accelerated in the critical regime.

    ↳ hep-thhep-phPRD(2022)·0 citations
25. 25*

    Bulk pressure in fluid-dynamical simulations of Pb-Pb and p-Pb collisions at the LHC energies

    Josef Bobek🇨🇿 · Iurii Karpenko (FNSPE CTU in Prague)🇨🇿

    State-of-the-art fluid dynamical simulations of relativistic heavy-ion collisions employ initial state models which result in a rather strong radial flow. In order to fit the experimental observables, a non-negligible bulk viscosity of the QGP and/or hadronic matter is required. We examine modern parametrizations of the bulk viscosity to entropy density ratio $\zeta /s$ used in recent fluid dynamical simulations, and explore the relative magnitude of the associated bulk viscous corrections in space-time, for Pb-Pb and p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV LHC energy with a state-of-the-art initial state provided by TRENTo model. It turns out that, at a typical particlization hypersurface, the effect of bulk viscosity out-competes the one of shear viscosity, and in a significantly large part of the space-time volume, the bulk pressure strongly counteracts the equilibrium pressure, thus the effective pressure approaches zero. The latter potentially challenges the applicability of fluid-dynamical modelling of heavy ion-ion and proton-ion collisions at the LHC energies.

    ↳ nucl-thhep-exhep-ph2 citations
26. 26*

    Nature of particles azimuthal anisotropy at low and high transverse momenta in ultrarelativistic A+A collisions

    L V Bravina🇳🇴 · G Kh Eyyubova🇷🇺 · V L Korotkikh🇷🇺 · I P Lokhtin🇷🇺 · S V Petrushanko🇷🇺 · A M Snigirev🇷🇺 · E E Zabrodin🇳🇴

    LHC data on the correlations of the elliptic flow $v_2$ of particles at low and high transverse momenta $p_T$ from Pb+Pb collisions at center-of-mass energy per nucleon pair $\sqrt{s_{NN}}=5.02$ TeV are analyzed in the framework of the HYDJET++ model. This model includes soft and hard components which allows to describe the region of both low and high transverse momenta. The origin of $v_2$ values in different $p_T$ regions is investigated at different centralities. It is shown that the experimentally observed correlations between $v_2$ at low and high $p_T$ in peripheral lead-lead collisions is due to correlation of particles in jets.

    ↳ nucl-thhep-phPhys.Scripta(2022)·1 citation
27. 27*

    Flat spectra of cosmic gravitons in the nHz and audio bands

    Massimo Giovannini🇨🇭

    The spectra of the relic gravitons are customarily normalized in the low-frequency domain where the signal of the concordance paradigm is expected to peak and this is why their contribution to the temperature and polarization anisotropies of the microwave background is only described by the tensor to scalar ratio. If the consistency relations are broken, the same strategy is accomplished by introducing the tensor spectral index as a further independent parameter. When the dominant component of the spectral energy density is distributed for frequencies much larger than the aHz, the logic behind this conventional approach is much less compelling. The improved bounds in the audio band and the current data from the pulsar timing arrays in the nHz region motivate a new strategy for the absolute normalization of the cosmic background of relic gravitons. After introducing a general four-dimensional action for the analysis of the relic gravitons the new approach is illustrated in the case of conventional and unconventional inflationary models.

    ↳ gr-qcastro-ph.COhep-phhep-thJCAP(2022)·2 citations
28. 28*

    Calculating critical temperature and critical exponents by self-similar approximants

    V.I. Yukalov🇷🇺 · E.P. Yukalova🇷🇺

    Self-similar approximation theory allows for defining effective sums of asymptotic series. The method of self-similar factor approximants is applied for calculating the critical temperature and critical exponents of the $O(N)$-symmetric ${\phi }^4$ field theory in three dimensions by summing asymptotic $\epsilon$ expansions. This method is shown to be essentially simpler than other summation techniques involving complicated numerical calculations, while enjoying comparable accuracy.

    ↳ cond-mat.stat-mechhep-phmath-phmath.MPJ.Phys.Conf.Ser.(2022)·0 citations
29. 29*

    Non-Minimal Inflation with a scalar-curvature mixing term $\frac{1}{2}\xi R{\varphi }^2$

    Payel Sarkar🇮🇳 · Ashmita🇮🇳 · Prasanta Kumar Das🇮🇳

    We use the PLANCK 2018 and the WMAP data to constraint inflation models driven by a scalar field $\varphi$ in the presence of the non-minimal scalar-curvature mixing term $\frac{1}{2}\xi R{\varphi }^2$. We consider four distinct scalar field potentials ${\varphi }^p{e}^{-\lambda \varphi },(1-{\varphi }^p)e^{-\lambda \varphi },(1-\lambda \varphi {)}^p$ and $\frac{\alpha {\varphi }^2}{1+\alpha {\varphi }^2}$ to study inflation in the non-minimal gravity theory. We calculate the potential slow-roll parameters and predict the scalar spectral index $n_s$ and the tensor-to-scalar ratio $r$, in the parameters ($\lambda ,p,\alpha$) space of the potentials. We have compared our results with the ones existing in the literature, and this indicates the present status of non-minimal inflation after the release of the PLANCK 2018 data.

    ↳ astro-ph.COgr-qchep-phAnnals Phys.(2023)·12 citations
30. 30*

    Gravitational Waves From No-Scale Supergravity

    Vassilis C. Spanos🇬🇷 · Ioanna D. Stamou🇬🇷

    In this paper we study four concrete models, based on no-scale supergravity with SU(2,1)/SU(2)$\times$ U(1) symmetry. We modify either the Kähler potential or the superpotential, which are related to the no-scale theory with this symmetry. In this scenario, the induced Gravitational Waves, are calculated to be detectable by the future space-based observations such as LISA, BBO and DECIGO. The models under study are interrelated, as they all yield the Starobinsky effective-like scalar potential in the unmodified case. We evaluate numerically the scalar power spectrum and the stochastic background of the Gravitational Waves, satisfying the observational Planck cosmological constraints for inflation.

    ↳ astro-ph.COgr-qchep-phhep-thEPJC(2023)·7 citations
31. 31*

    Enhancing gravitational wave anisotropies with peaked scalar sources

    Ema Dimastrogiovanni🇳🇱 · Matteo Fasiello🇪🇸 · Ameek Malhotra🇦🇺 · Gianmassimo Tasinato🇬🇧

    Gravitational wave (GW) backgrounds of cosmological origin are expected to be nearly isotropic, with small anisotropies resembling those of the cosmic microwave background. We analyse the case of a scalar-induced GW background and clarify in the process the relation between two different approaches to calculating GW anisotropies. We focus on GW scenarios sourced by a significantly peaked scalar spectrum, which are frequently considered in the context of primordial black holes production. We show that the resulting GW anisotropies are characterised by a distinct frequency dependence. We explore the observational consequences concentrating on a GW background enhanced in the frequency band of space-based GW detectors. We study the detectability of the signal through both cross-correlations among different space-based GW detectors, and among GW and CMB experiments.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2023)·42 citations
32. 32*

    Bubble dynamics in fluids with N-body simulations

    Marek Lewicki🇵🇱 · Ville Vaskonen🇪🇸 · Hardi Veermäe🇪🇪

    We present a new approach to studies of bubble dynamics in fluids. Relying on particle-based simulations, this method is general and suitable for cases where the commonly used perfect fluid description fails. We study expanding true vacuum bubbles surrounded by free or self-interacting particles and quantify how self-interactions affect the terminal bubble wall velocity. We find that, for sufficiently strongly self-interacting fluids, local thermal equilibrium is maintained around the bubble wall and the fluid profile is similar to that obtained with the perfect fluid description.

    ↳ astro-ph.COhep-phPRD(2022)·24 citations
33. 33*

    Quark formation and phenomenology in binary neutron-star mergers using V-QCD

    Samuel Tootle🇩🇪 · Christian Ecker🇩🇪 · Konrad Topolski🇩🇪 · Tuna Demircik🇰🇷 · Matti Järvinen🇰🇷 · Luciano Rezzolla🇩🇪

    Using full 3+1 dimensional general-relativistic hydrodynamic simulations of equal- and unequal-mass neutron-star binaries with properties that are consistent with those inferred from the inspiral of GW170817, we perform a detailed study of the quark-formation processes that could take place after merger. We use three equations of state consistent with current pulsar observations derived from a novel finite-temperature framework based on V-QCD, a non-perturbative gauge/gravity model for Quantum Chromodynamics. In this way, we identify three different post-merger stages at which mixed baryonic and quark matter, as well as pure quark matter, are generated. A phase transition triggered collapse already $\lesssim 10\mathrm{ms}$ after the merger reveals that the softest version of our equations of state is actually inconsistent with the expected second-long post-merger lifetime of GW170817. Our results underline the impact that multi-messenger observations of binary neutron-star mergers can have in constraining the equation of state of nuclear matter, especially in its most extreme regimes.

    ↳ astro-ph.HEgr-qchep-phnucl-thSciPost Phys.(2022)·66 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.