Thu·Apr 11, 2024Thursday·April 11, 2024

1. 01*

   A common framework for fermion mass hierarchy, leptogenesis and dark matter

   Carolina Arbeláez🇨🇱 · A.E. Cárcamo Hernández🇨🇱 · Claudio Dib🇨🇱 · Patricio Escalona Contreras🇨🇱 · Vishnudath K. N.🇨🇱 · Alfonso Zerwekh🇨🇱

   In this work, we explore an extension of the Standard Model designed to elucidate the fermion mass hierarchy, account for the dark matter relic abundance, and explain the observed matter-antimatter asymmetry in the universe. Beyond the Standard Model particle content, our model introduces additional scalars and fermions. Notably, the light active neutrinos and the first two generations of charged fermions acquire masses at the one-loop level. The model accommodates successful low-scale leptogenesis, permitting the mass of the decaying heavy right-handed neutrino to be as low as 10 TeV. We conduct a detailed analysis of the dark matter phenomenology and explore various interesting phenomenological implications. These include charged lepton flavor violation, muon and electron anomalous magnetic moments, constraints arising from electroweak precision observables, and implications for collider experiments.

   hep-phJHEP(2024)·5 citations
2. 02*

   Non-extensive Effects on the QCD Equation of State and Fluctuations of Conserved Charges within Polyakov Quark Meson Model

   Abdel Magied Diab🇪🇬

   The influence of non-extensive Tsallis statistics on the hadron phase structure has been investigated using the Polyakov-quark-meson (PQM) model. The analysis examines the non-extensive effects on the temperature dependence of PQM order parameters, thermodynamic quantities related to the QCD equation of state, and fluctuations of conserved charges at varying chemical potentials. The results show that non-extensive effects have the most significant deviations near the crossover region. The pseudo-critical temperature $T_{\chi }({\mu }_B)$ is not a universal constant and decreases with increasing non-extensive $q$ parameter. The chiral phase diagram of the PQM model indicates a decrease in the behavior of the ($T_{\chi }-{\mu }_B$) plane with increasing non-extensive $q$ parameter. The PQM model exhibits good qualitative agreement with lattice QCD calculations. Moreover, these findings suggest the existence of a Tsallis limit, which serves as an alternative to the Stefan-Boltzmann (SB) limit for the massless ideal gas. The critical endpoint (CEP) exhibits lower temperature but higher chemical potential with increasing non-extensive $q$ parameter. Overall, this study highlights the importance of non-extensive Tsallis statistics in characterizing the quark-hadron phase structure of the PQM model and contributes to a deeper understanding of non-extensive effects in the quark-hadron phase transition.

   hep-phhep-thJ.Phys.G(2024)·1 citation
3. 03*

   Mediator Decay through mixing with Degenerate Spectrum

   Ayuki Kamada🇵🇱 · Takumi Kuwahara🇨🇳 · Shigeki Matsumoto🇯🇵 · Yu Watanabe🇯🇵 · Yuki Watanabe🇯🇵

   The decay of the mediator particle into standard model (SM) particles plays a significant role in exploring the dark sector scenario. We consider such a decay, taking the dark photon mediator as an example that mixes with the SM photon. We find that it requires a careful analysis of the decay rate in the presence of an SM vector boson (e.g., $Z$ boson, $\rho$ meson, and true muonium, etc.) nearly degenerate with the mediator particle in mass. The decay rate of the mediator particle calculated in the mass eigenstate basis {\bf does not} agree with the correct result, given by the imaginary parts of the poles for the vector boson propagators, when the mixing parameter is smaller than a specific value. In such a case, the decay rate calculated by treating the mixing as a perturbative parameter is in agreement with the correct result. We clarify specific values for the mixing parameter quantitatively using several concrete examples of the SM vector bosons degenerate with the dark photon. When the mass mixing between the vector boson and dark photon is smaller (larger) than the decay width of the vector boson, the latter (former) method to calculate the decay rate of the mediator particle gives the correct result.

   hep-phJHEP(2025)·5 citations
4. 04*

   The non-perturbative Sudakov Form Factor and the role of soft gluons

   H. Jung🇩🇪

   The role of soft gluons in inclusive collinear parton densities as well as in Transverse Momentum Dependent (TMD) parton densities is discussed. Applying the Parton-Branching (PBM) method, the so-called non-perturbative Sudakov form factor could be identified with the integration range $z\to 1$, which is neglected in collinear parton shower approaches. The importance of soft gluons could be shown by investigating the transverse momentum spectrum of Drell-Yan lepton pairs, leading to a width of the intrinsic-$k_T$ distribution which is independent on $\sqrt{s}$ , in contrast to what is observed in parton shower approaches. The reason for this behavior is traced back to the non-perturbative Sudakov form factor. The role of soft gluons for observable hadron spectra is discussed and shown to be negligible. This talk is dedicated to the memory of S. Jadach.

   hep-ph2 citations
5. 05*

   Shadowing and antishadowing in the rescaling model

   A.V. Kotikov🇷🇺 · A.V. Lipatov🇷🇺 · P.M. Zhang🇨🇳

   Nuclear deep inelastic structure functions F_2^A(x,Q^2) as well as parton distribution functions in a nuclei are investigated in the framework of rescaling model. Our analysis is based on analytical expressions for quark and gluon densities in a proton derived at the leading order of QCD coupling. By fitting the rescaling parameters from the experimental data on F_2^A(x,Q^2)/F_2^D(x,Q^2) ratio for several nuclear targets, we derive predictions for corresponding nuclear parton distributions and, thus, for shadowing and antishadowing effects.

   hep-phPisma Zh.Eksp.Teor.Fiz.(2024)·3 citations
6. 06*

   Constraining Bosonic Dark Matter-Baryon Interactions from Neutron Star Collapse

   Chih-Ting Lu🇨🇳 · Arvind Kumar Mishra🇨🇳 · Lei Wu🇨🇳

   Dark matter (DM) may be captured around a neutron star (NS) through DM-nucleon interactions. We observe that the enhancement of such capturing is particularly significant when the DM velocity and/or momentum transfer depend on the DM-nucleon scattering cross-section. This could potentially lead to the formation of a black hole within the typical lifetime of the NS. As the black hole expands through the accretion of matter from the NS, it ultimately results in the collapse of the host. Utilizing the existing pulsar data J0437-4715 and J2124-3858, we derive the stringent constraints on the DM-nucleon scattering cross-section across a broad range of DM masses.

   hep-phJCAP(2024)·12 citations
7. 07*

   Complete Optimal Non-Resonant Anomaly Detection

   Gregor Kasieczka🇩🇪 · John Andrew Raine🇨🇭 · David Shih🇺🇸 · Aman Upadhyay

   We propose the first-ever complete, model-agnostic search strategy based on the optimal anomaly score, for new physics on the tails of distributions. Signal sensitivity is achieved via a classifier trained on auxiliary features in a weakly-supervised fashion, and backgrounds are predicted using the ABCD method in the classifier output and the primary tail feature. The independence between the classifier output and the tail feature required for ABCD is achieved by first training a conditional normalizing flow that yields a decorrelated version of the auxiliary features; the classifier is then trained on these features. Both the signal sensitivity and background prediction require a sample of events accurately approximating the SM background; we assume this can be furnished by closely related control processes in the data or by accurate simulations, as is the case in countless conventional analyses. The viability of our approach is demonstrated for signatures consisting of (mono)jets and missing transverse energy, where the main SM background is $Z(\nu \nu )+\text{jets}$, and the data-driven control process is $\gamma +\text{jets}$.

   hep-phhep-exphysics.data-an6 citations
8. 08*

   Gravitational production of massive scalars in the context of inflation

   Urjit A. Yajnik🇮🇳

   We set up a formalism for calculating the energy density generated in a quantized massive scalar field in the course of the drastic change in spacetime geometry at the end of the inflationary era. The calculation relies on the notion of adiabatic vacuum. The Bogolubov coefficients are computed by employing the sudden approximation. After obtaining a general formula, we calculate explicitly the energy density generated in a particle species with $m/H\ll 1$, where $m$ is the particle mass and $H$ is the Hubble constant during the inflationary epoch. We find the contribution of the long-wavelength modes to be $\propto H^5/m$. If such particles are very weakly interacting, they can come to dominate the total energy density in the Universe. Other cosmological implications are also discussed.

   ↳ astro-ph.COgr-qchep-phhep-th1 citation
9. 09*

   Constraining Cosmological Physics with DESI BAO Observations

   Deng Wang🇪🇸

   The DESI year one observations can help probe new physics on cosmological scales. In light of the latest DESI BAO measurements, we constrain five popular cosmological scenarios including inflation, modified gravity, annihilating dark matter and interacting dark energy. Using a data combination of BICEP/Keck array, cosmic microwave background and DESI, we obtain the $1\sigma$ and $2\sigma$ constraints on the tensor-to-scalar ratio $r_{0.05}=0.0176_{-0.0130}^{+0.0070}$ and $r_{0.05}=0.018_{-0.017}^{+0.020}$ indicating a beyond $2\sigma$ evidence of primordial gravitational waves. Using the combination of cosmic microwave background and DESI, we find a $2.4\sigma$ evidence for gravitational theories beyond the general relativity, shrink the dark matter annihilation cross-section by $12\%$ relative to cosmic microwave background, obtain a $1.3\sigma$ hint of the positive interaction between dark matter and dark energy implying that energy may be transferred from dark matter to dark energy in the dark sector of the universe, and give a clue of massive sterile neutrinos via the $2\sigma$ constraint on the effective number of relativistic degrees of freedom $N_{eff}=3.16_{-0.11}^{+0.26}$ and the effective mass $m_{\nu ,sterile}^{eff}<0.52$ eV. Future DESI observations could go a step further to explore the nature of inflation, dark matter, dark energy and neutrinos, and test the validity of general relativity on cosmological scales.

   ↳ astro-ph.COgr-qchep-phhep-th61 citations
10. 10*

    Tidal Love numbers and approximate universal relations for fermion soliton stars

    Emanuele Berti🇺🇸 · Valerio De Luca🇺🇸 · Loris Del Grosso🇮🇹 · Paolo Pani🇮🇹

    Fermion soliton stars are a consistent model of exotic compact objects which involve a nonlinear interaction between a real scalar field and fermions through a Yukawa term. This interaction results in an effective fermion mass that depends upon the vacuum structure in the scalar potential. In this work we investigate the tidal deformations of fermion soliton stars and compute the corresponding tidal Love numbers for different model parameters. Furthermore, we discuss the existence of approximate universal relations for the electric and magnetic tidal deformabilities of these stars, and compare them with other solutions of general relativity, such as neutron stars or boson stars. These relations for fermion soliton stars are less universal than for neutron stars, but they are sufficiently different from the ordinary neutron star case that a measurement of the electric and magnetic tidal Love numbers (as potentially achievable by next-generation gravitational wave detectors) can be used to disentangle these families of compact objects. Finally, we discuss the conditions for tidal disruption of fermion soliton stars in a binary system and estimate the detectability of the electromagnetic signal associated with such tidal disruption events.

    ↳ gr-qchep-phhep-thPRD(2024)·28 citations
11. 11*

    First constraints on the $L_{\mu }-L_{\tau }$ explanation of the muon $g-2$ anomaly from NA64-$e$ at CERN

    Yu. M. Andreev · A. Antonov🇮🇹 · D. Banerjee🇨🇭 · B. Banto Oberhauser🇨🇭 · J. Bernhard🇨🇭 · P. Bisio🇮🇹 · A. Celentano🇮🇹 · N. Charitonidis🇨🇭 · D. Cooke🇬🇧 · P. Crivelli🇨🇭 · E. Depero🇨🇭 · A. V. Dermenev and 49 other authors

    The inclusion of an additional $U(1)$ gauge $L_{\mu }-L_{\tau }$ symmetry would release the tension between the measured and the predicted value of the anomalous muon magnetic moment: this paradigm assumes the existence of a new, light $Z^{\prime }$ vector boson, with dominant coupling to $\mu$ and $\tau$ leptons and interacting with electrons via a loop mechanism. The $L_{\mu }-L_{\tau }$ model can also explain the Dark Matter relic abundance, by assuming that the $Z^{\prime }$ boson acts as a "portal" to a new Dark Sector of particles in Nature, not charged under known interactions. In this work we present the results of the $Z^{\prime }$ search performed by the NA64-$e$ experiment at CERN SPS, that collected $\sim 9\times 10^{11}$ 100 GeV electrons impinging on an active thick target. Despite the suppressed $Z^{\prime }$ production yield with an electron beam, NA64-$e$ provides the first accelerator-based results excluding the $g-2$ preferred band of the $Z^{\prime }$ parameter space in the 1 keV $<m_{Z^{\prime }}\lesssim 2$ MeV range, in complementarity with the limits recently obtained by the NA64-$\mu$ experiment with a muon beam.

    ↳ hep-exhep-phJHEP(2024)·19 citations
12. 12*

    Constraining the UV with the electroweak effective action

    Iberê Kuntz🇧🇷 · Amanda Malagi🇧🇷

    By considering an arbitrary bare action describing BSM physics, we use the Barvinsky-Vilkovisky resummation to obtain the most general non-local electroweak effective action at second order in the field strength. We also include the contribution of the functional measure to the effective action, which is found to modify the Higgs potential by shifting its vacuum value. The resulting effective action provides one-loop corrections to the $W$ and $Z$ boson masses, ultimately leading to the most general expression for the $\rho$ parameter at one-loop. The functional measure plays a pivotal role as it allows the parameterization of $\rho$ in inverse powers of the scale of new physics, while containing non-local form factors. The comparison of $\rho$ with the latest data leads to several constraints on the UV particle spectra of BSM models.

    ↳ hep-thhep-phJHEP(2025)·3 citations
13. 13*

    Hilbert space representation for quasi-Hermitian position-deformed Heisenberg algebra and Path integral formulation

    Thomas Katsekpor🇿🇦 · Latévi M. Lawson🇿🇦 · Prince K. Osei🇿🇦 · Ibrahim Nonkané🇧🇫

    Position deformation of a Heisenberg algebra and Hilbert space representation of both maximal length and minimal momentum uncertainties may lead to loss of Hermiticity of some operators that generate this algebra. Consequently, the Hamiltonian operator constructed from these operators are also not Hermitian. In the present paper, with an appropriate positive-definite Dyson map, we establish the Hermiticity of these operators by means of a quasi-similarity transformation. We then construct Hilbert space representations associated with these quasi-Hermitian operators that generate a quasi-Hermitian Heisenberg algebra. With the help of these representations we establish the path integral formulation of any systems in this quasi-Hermitian algebra. Finally, using the path integral of a free particle as an example, we demonstrate that the Euclidean propagator, action, and kinetic energy of this system are constrained by the standard classical mechanics limits.

    ↳ math-phcond-mat.otherhep-phhep-th+2Rev.Math.Phys.(2026)·0 citations
14. 14*

    One-loop power spectrum in ultra slow-roll inflation and implications for primordial black hole dark matter

    Guillermo Ballesteros🇪🇸 · Jesús Gambín Egea🇪🇸

    We apply the in-in formalism to address the question of whether the size of the one-loop spectrum of curvature fluctuations in ultra-slow-roll inflation models designed for producing a large population of primordial black holes implies a breakdown of perturbation theory. We consider a simplified piece-wise description of inflation, in which the ultra-slow-roll phase is preceded and followed by slow-roll phases linked by transitional periods. We work in the $\delta \varphi$-gauge, including all relevant cubic and quartic interactions and the necessary counterterms to renormalize the ultraviolet divergences, regularized by a cutoff. The ratio of the one-loop to the tree-level contributions to the spectrum of curvature perturbations is controlled by the duration of the ultra-slow-roll phase and of the transitions. Our results indicate that perturbation theory does not necessarily break in well-known models proposed to account for all the dark matter in the form of primordial black holes.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2024)·59 citations
15. 15*

    Searching for Cosmological Collider in the Planck CMB Data

    Wuhyun Sohn🇰🇷 · Dong-Gang Wang🇬🇧 · James R. Fergusson🇬🇧 · E. P. S. Shellard🇬🇧

    In this paper, we present the first comprehensive CMB data analysis of cosmological collider physics. New heavy particles during inflation can leave imprints in the primordial correlators which are observable in today's cosmological surveys. This remarkable detection channel provides an unsurpassed opportunity to probe new physics at extremely high energies. Here we initiate the search for these relic signals in the cosmic microwave background (CMB) data from the Planck legacy release. On the theory side, guided by recent progress from the cosmological bootstrap, we first propose a family of analytic bispectrum templates that incorporate the distinctive signatures of cosmological collider physics. Our consideration includes the oscillatory signals in the squeezed limit, the angular dependence from spinning fields, and several new shapes from nontrivial sound speed effects. On the observational side, we apply the recently developed pipeline, CMB Bispectrum Estimator (CMB-BEST), to efficiently analyze the three-point statistics and search directly for these new templates in the Planck 2018 temperature and polarization data. We report stringent CMB constraints on these new templates. Furthermore, we perform parameter scans to search for the best-fit values with maximum significance. For a benchmark example of collider templates, we find $f_{NL}=-91\pm 40$ at the $68\%$ confidence level. After accounting for the look-elsewhere effect, the biggest adjusted significance we get is $1.8\sigma$. In general, we find no significant evidence of cosmological collider signals in the Planck data. However, this innovative analysis demonstrates the potential for discovering new heavy particles during inflation in forthcoming cosmological surveys.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2024)·66 citations
16. 16*

    PolyBin3D: A Suite of Optimal and Efficient Power Spectrum and Bispectrum Estimators for Large-Scale Structure

    Oliver H. E. Philcox🇺🇸 · Thomas Flöss

    By measuring, modeling and interpreting cosmological datasets, one can place strong constraints on models of the Universe. Central to this effort are summary statistics such as power spectra and bispectra, which condense the high-dimensional data into low-dimensional representations. In this work, we introduce a modern set of estimators for computing such statistics from three-dimensional clustering data, and provide a flexible Python/Cython implementation; PolyBin3D. Working in a maximum-likelihood formalism, we derive general estimators for the two- and three-point functions, which yield unbiased spectra regardless of the survey mask and weighting scheme. These can be directly compared to theory without the need for mask-convolution. Furthermore, we present a numerical scheme for computing the optimal (minimum-variance) estimators for a given survey, which is shown to reduce error-bars on large-scales. Our Python package includes both general "unwindowed" estimators and their idealized equivalents (appropriate for simulations), each of which are efficiently implemented using fast Fourier transforms and Monte Carlo summation tricks, and additionally supports GPU acceleration using JAX. These are extensively validated in this work, with Monte Carlo convergence (relevant for masked data) achieved using only a small number of iterations (typically $<10$ for bispectra). This will allow for fast and unified measurement of two- and three-point functions from current and upcoming survey data.

    ↳ astro-ph.COastro-ph.GAhep-exhep-ph+1PRD(2025)·24 citations
17. 17*

    Reionization after JWST: a photon budget crisis?

    Julian B. Muñoz🇺🇸 · Jordan Mirocha🇨🇦 · John Chisholm · Steven R. Furlanetto · Charlotte Mason

    New James Webb Space Telescope (JWST) observations are revealing the first galaxies to be prolific producers of ionizing photons, which we argue gives rise to a tension between different probes of reionization. Over the last two decades a consensus has emerged where star-forming galaxies are able to generate enough photons to drive reionization, given reasonable values for their number densities, ionizing efficiencies ${\xi }_{\mathrm{ion}}$ (per unit UV luminosity), and escape fractions $f_{\mathrm{esc}}$. However, some new JWST observations infer high values of ${\xi }_{\mathrm{ion}}$ during reionization and an enhanced abundance of earlier ($z\gtrsim 9$) galaxies, dramatically increasing the number of ionizing photons produced at high $z$. Simultaneously, recent low-$z$ studies predict significant escape fractions for faint reionization-era galaxies. Put together, we show that the galaxies we have directly observed ($M_{\mathrm{UV}}<-15$) not only can drive reionization, but would end it too early. That is, our current galaxy observations, taken at face value, imply an excess of ionizing photons and thus a process of reionization in tension with the cosmic microwave background (CMB) and Lyman-$\alpha$ forest. Considering galaxies down to $M_{\mathrm{UV}}\approx -11$, below current observational limits, only worsens this tension. We discuss possible avenues to resolve this photon budget crisis, including systematics in either theory or observations.

    ↳ astro-ph.COastro-ph.GAhep-phMNRAS(2024)·94 citations
18. 18*

    Hot New Early Dark Energy bridging cosmic gaps: Supercooled phase transition reconciles (stepped) dark radiation solutions to the Hubble tension with BBN

    Mathias Garny🇩🇪 · Florian Niedermann🇸🇪 · Henrique Rubira🇩🇪 · Martin S. Sloth🇩🇰

    We propose a simple model that can alleviate the $H_0$ tension while remaining consistent with big bang nucleosynthesis (BBN). It is based on a dark sector described by a standard Lagrangian featuring a $SU(N)$ gauge symmetry with $N\ge 3$ and a massive scalar field with a quartic coupling. The scalar acts as dark Higgs leading to spontaneous symmetry breaking $SU(N)\to SU(N-1)$ via a first-order phase transition à la Coleman-Weinberg. This set-up naturally realizes previously proposed scenarios featuring strongly interacting dark radiation (SIDR) with a mass threshold within hot new early dark energy (NEDE). For a wide range of reasonable model parameters, the phase transition occurs between the BBN and recombination epochs and releases a sufficient amount of latent heat such that the model easily respects bounds on extra radiation during BBN while featuring a sufficient SIDR density around recombination for increasing the value of $H_0$ inferred from the cosmic microwave background. Our model can be summarized as a natural mechanism providing two successive increases in the effective number of relativistic degrees of freedom after BBN but before recombination $\Delta N_{\mathrm{BBN}}\to \Delta N_{\mathrm{NEDE}}\to \Delta N_{\mathrm{IR}}$ alleviating the Hubble tension. The first step is related to the phase transition and the second to the dark Higgs becoming non-relativistic. This set-up predicts further signatures, including a stochastic gravitational wave background and features in the matter power spectrum that can be searched for with future pulsar timing and Lyman-$\alpha$ forest measurements.

    ↳ astro-ph.COhep-phPRD(2024)·38 citations
19. 19*

    Testing the standardizability of, and deriving cosmological constraints from, a new Amati-correlated gamma-ray burst data compilation

    Shulei Cao🇺🇸 · Bharat Ratra🇺🇸

    By using gamma-ray burst (GRB) data to simultaneously constrain Amati correlation parameters and cosmological parameters in six spatially-flat and nonflat dark energy cosmological models, we show that an updated 220 GRB version of the Jia et al. [Mon. Not. R. Astron. Soc. 516, 2575 (2022)] GRB data compilation are standardizable through the Amati correlation and so can be used for cosmological analyses. However, the resulting GRB data constraints on the current value of the nonrelativistic matter density parameter, ${\Omega }_{m0}$, are in $>2\sigma$ tension with those from a joint analysis of better-established Hubble parameter [$H(z)$] and baryon acoustic oscillation (BAO) data for most of the cosmological models we consider, indicating that these GRB data cannot be jointly used with better-established $H(z)$ + BAO data to constrain cosmological parameters.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2024)·19 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.