Wed·Nov 8, 2023Wednesday·November 8, 2023

1. 01*

   Cosmic Birefringence from CP-Violating Axion Interactions

   Xuheng Luo🇺🇸 · Anubhav Mathur🇺🇸

   We explore the cosmic birefringence signal produced by an ultralight axion field with a small CP-violating coupling to bulk SM matter in addition to the usual CP-preserving photon coupling. The change in the vacuum expectation value of the field between recombination and today results in a frequency-independent rotation of the plane of CMB linear polarization across the entire sky. While many previous approaches rely on the axion rolling from a large initial expectation value, the couplings considered in this work robustly generate the birefringence signal regardless of initial conditions, by sourcing the field from the cosmological nucleon density. We place bounds on such monopole-dipole interactions using measurements of the birefringence angle from Planck and WMAP data, which improve upon existing constraints by up to three orders of magnitude. We also discuss UV completions of this model, and possible strategies to avoid fine-tuning the axion mass.

   hep-phastro-ph.COhep-thJHEP(2024)·10 citations
2. 02*

   Secondary Lepton Production, Propagation, and Interactions with NuLeptonSim

   Austin Cummings🇺🇸 · Ryan Krebs🇺🇸 · Stephanie Wissel🇺🇸 · Jaime Alvarez-Muñiz🇪🇸 · Washington R. Carvalho Jr.🇳🇱 · Andrés Romero-Wolf🇺🇸 · Harm Schoorlemmer🇩🇪 · Enrique Zas🇪🇸

   Charged current interactions of neutrinos inside the Earth can result in secondary muons and $\tau$-leptons which are detectable by several existing and planned neutrino experiments through a wide variety of event topologies. Consideration of such events can improve detector performance and provide unique signatures which help with event reconstruction. In this work, we describe NuLeptonSim, a propagation tool for neutrinos and charged leptons that builds on the fast NuTauSim framework. NuLeptonSim considers energy losses of charged leptons, modelled both continuously for performance or stochastically for accuracy, as well as interaction models for all flavors of neutrinos, including the Glashow resonance. We demonstrate the results from including these effects on the Earth emergence probability of various charged leptons from different flavors of primary neutrino and their corresponding energy distributions. We find that the emergence probability of muons can be higher than that of taus for energies below 100 PeV, whether from a primary muon or $\tau$ neutrino, and that the Glashow resonance contributes to a surplus of emerging leptons near the resonant energy.

   hep-phPRD(2025)·11 citations
3. 03*

   Modeling spin effects in electron-positron annihilation to hadrons

   A. Kerbizi🇮🇹 · X. Artru🇫🇷

   The string+${}^3{P}_0$ model of spin-dependent hadronization is applied to the fragmentation of a string stretched between a quark and an antiquark with entangled spin states, assumed to be produced in the $e^{+}{e}^{-}$ annihilation process. The model accounts systematically for the spin correlations in the hadronization chain and is formulated as a recursive recipe suitable for the implementation in a Monte Carlo event generator. The recipe is applied to the production of two back-to-back pseudoscalar mesons produced in $e^{+}{e}^{-}$ annihilation, and it is shown to reproduce the form of the azimuthal distribution of the hadrons as expected in QCD.

   hep-phNuovo Cim.C(2024)·0 citations
4. 04*

   P wave mesons emitting weak decays of bottom mesons

   Maninder Kaur🇮🇳 · Supreet Pal Singh🇮🇳 · R C Verma🇮🇳

   This paper is the extension of our previous work entitled Searching a systematics for nonfactorizable contributions to and hadronic decays. Obtaining the factorizable contributions from the spectator quark model for a systematics has been identified among the isospin reduced amplitudes for the nonfactorizable terms among decay modes. This systematics helps us to derive a generic formula which assists to predict the branching fractions for Inspired by this observation, we extend our analysis to p wave meson emitting decays of which have similar isospin structure and make predictions for where the experimental measurements are not yet available.

   hep-phCPC(2025)·3 citations
5. 05*

   Effects of Renormalon Scheme and Perturbative Scale Choices on Determinations of the Strong Coupling from $e^{+}{e}^{-}$ Event Shapes

   Guido Bell🇩🇪 · Christopher Lee🇺🇸 · Yiannis Makris🇺🇸 · Jim Talbert🇬🇧 · Bin Yan🇨🇳

   We study the role of renormalon cancellation schemes and perturbative scale choices in extractions of the strong coupling constant ${\alpha }_s(m_Z)$ and the leading non-perturbative shift parameter ${\Omega }_1$ from resummed predictions of the $e^{+}{e}^{-}$ event shape thrust. We calculate the thrust distribution to N${}^3$LL${}^{\prime }$ resummed accuracy in Soft-Collinear Effective Theory (SCET) matched to the fixed-order $\mathcal{O}({\alpha }_s^2)$ prediction, and perform a new high-statistics computation of the $\mathcal{O}({\alpha }_s^3)$ matching in EERAD3, although we do not include the latter in our final ${\alpha }_s$ fits due to some observed systematics that require further investigation. We are primarily interested in testing the phenomenological impact sourced from varying amongst three renormalon cancellation schemes and two sets of perturbative scale profile choices. We then perform a global fit to available data spanning center-of-mass energies between 35-207 GeV in each scenario. Relevant subsets of our results are consistent with prior SCET-based extractions of ${\alpha }_s(m_Z)$, but we are also led to a number of novel observations. Notably, we find that the combined effect of altering the renormalon cancellation scheme and profile parameters can lead to few-percent-level impacts on the extracted values in the ${\alpha }_s-{\Omega }_1$ plane, indicating a potentially important systematic theory uncertainty that should be accounted for. We also observe that fits performed over windows dominated by dijet events are typically of a higher quality than those that extend into the far tails of the distributions, possibly motivating future fits focused more heavily in this region. Finally, we discuss how different estimates of the three-loop soft matching coefficient $c_{\tilde{S}}^3$ can also lead to measurable changes in the fitted $\{{\alpha }_s,{\Omega }_1\}$ values.

   hep-phPRD(2024)·29 citations
6. 06*

   Quantum collider probes of the fermionic Higgs portal

   U. Haisch🇩🇪 · M. Ruhdorfer🇺🇸 · K. Schmid🇮🇹 · A. Weiler🇩🇪

   We explore the sensitivity of future hadron colliders to constrain the fermionic Higgs portal, with a focus on scenarios where the new fermions cannot be directly observed in exotic Higgs decays. This portal emerges in various models including twin-Higgs scenarios and dark matter models, posing significant challenges for collider tests. Working in an effective field theory (EFT), we determine the reach of the high-luminosity option of the Large Hadron Collider (HL-LHC), the high-energy upgrade of the LHC (HE-LHC) and a proposed Future Circular Collider (FCC) in probing the fermionic Higgs portal through off-shell and double-Higgs production. Notably, we find that quantum-enhanced indirect probes offer a better sensitivity than other direct Higgs measurements. We argue that this finding is valid in a wide class of ultraviolet realisations of the EFT. Our study presents a roadmap of a multifaceted search strategy for exploring the fermionic Higgs portal at forthcoming hadron machines.

   hep-phhep-exSciPost Phys.(2024)·7 citations
7. 07*

   The flavor of a minimal composite $S_1$ leptoquark and the $b\to c\tau \bar{\nu }$ anomaly

   Leandro Da Rold🇦🇷

   Several experiments have measured a deviation in $B\to D^{(\ast )}$ semileptonic decays, that point to new physics at the TeV scale violating lepton flavor universality. A scalar leptoquark $S_1$, with a suitable structure of couplings in flavor space, is known to be able to solve this anomaly modifying $b\to c\tau \bar{\nu }$. In the context of composite Higgs models, we consider a theory containing $H$ and $S_1$ as Nambu-Goldstone bosons (NGBs) of a new strongly interacting sector, with ordinary resonances at a scale $\mathcal{O}(10)$ TeV. Assuming anarchic partial compositeness of the Standard Model (SM) fermions we calculate the potential of the NGBs that is dominated by the fermions of the third generation, we compute $R_{D^{(\ast )}}$ and estimate the corrections to flavor observables by the presence of $S_1$. We find that the SM spectrum and $m_{S_1}\sim$ TeV can be obtained with a NGB decay constant of order $\sim 5$ TeV. We obtain a robust correlation between the main corrections to $R_{D^{(\ast )}}$, $B_{K^{(\ast )}\nu \nu }$ and $g_{\tau }/g_{\mu }$, that leads to a sever bound on $R_{D^{(\ast )}}$, roughly $2\sigma$ below the experimental value. Besides the bounds on the flavor observables $g_{\tau }^W$, BR$(\tau \to \mu \gamma )$ and $\Delta m_{B_s}$ are saturated, with the first one requiring a coupling between resonances $g_{\ast }\lesssim 2$, whereas the second one demands $m_{S_1}\gtrsim 1.7$ TeV, up to corrections of $\mathcal{O}(1)$.

   hep-phhep-exJHEP(2024)·3 citations
8. 08*

   Spin-Flavor Oscillations of Relic Neutrinos in Primordial Magnetic Field

   Ashutosh Kumar Alok🇮🇳 · Trambak Jyoti Chall🇮🇳 · Neetu Raj Singh Chundawat🇮🇳 · Arindam Mandal🇮🇳

   The neutrino magnetic moment operator clasps a tiny but non-zero value within the standard model (SM) of particle physics and rather enhanced values in various new physics models. This generation of the magnetic moment (${\mu }_{\nu }$) is through quantum loop corrections which can exhibit spin-flavor oscillations in the presence of an external magnetic field. Also, several studies predict the existence of a primordial magnetic field (PMF) in the early universe, extending back to the era of Big Bang Nucleosynthesis (BBN) and before. The recent NANOGrav measurement can be considered as a strong indication of the presence of these PMFs. In this work, we consider the effect of the PMF on the flux of relic neutrinos. For Dirac neutrinos, we show that half of the active relic neutrinos can become sterile due to spin-flavor oscillations well before becoming non-relativistic owing to the expansion of the Universe and also before the timeline of the formation of galaxies and hence intergalactic fields, subject to the constraints on the combined value of ${\mu }_{\nu }$ and the cosmic magnetic field at the time of neutrino decoupling. For the upper limit of PMF allowed by the BBN, this can be true even if the experimental bounds on ${\mu }_{\nu }$ approaches a few times its SM value.

   hep-phastro-ph.COPRD(2024)·7 citations
9. 09*

   On the Normalisation of the Modular Forms in Modular Invariant Theories of Flavour

   S. T. Petcov🇮🇹

   The problem of normalisation of the modular forms in modular invariant lepton and quark flavour models is discussed. Modular invariant normalisations of the modular forms are proposed.

   hep-phhep-thPLB(2024)·13 citations
10. 10*

    Production of two, three, and four Higgs bosons: where SMEFT and HEFT depart

    Rafael L. Delgado🇪🇸 · Raquel Gómez-Ambrosio🇮🇹 · Javier Martínez-Martín🇪🇸 · Alexandre Salas-Bernárdez🇪🇸 · Juan J. Sanz-Cillero🇪🇸

    In this article we study the phenomenological implications of multiple Higgs boson production from longitudinal vector boson scattering in the context of effective field theories. We find compact representations for effective tree-level amplitudes with up to four final state Higgs bosons. Total cross sections are then computed for scenarios relevant at the LHC in which we find the general Higgs Effective Theory (HEFT) prediction avoids the heavy suppression observed in Standard Model Effective Field Theory (SMEFT).

    hep-phJHEP(2024)·36 citations
11. 11*

    Universal features of $2\to N$ scattering in QCD and gravity from shockwave collisions

    Himanshu Raj🇺🇸 · Raju Venugopalan🇺🇸

    A remarkable double copy relation of Einstein gravity to QCD in Regge asymptotics is ${\Gamma }^{\mu \nu }=\frac{1}{2}{C}^{\mu }{C}^{\nu }-\frac{1}{2}{N}^{\mu }{N}^{\nu }$, where ${\Gamma }^{\mu \nu }$ is the gravitational Lipatov vertex in the $2\to 3$ graviton scattering amplitude, $C^{\mu }$ its Yang-Mills counterpart, and $N^{\mu }$ the QED bremssstrahlung vertex. In QCD, the Lipatov vertex is a fundamental building block of the BFKL equation describing $2\to N$ scattering of gluons at high energies. Likewise, the gravitational Lipatov vertex is a key ingredient in a 2-D effective field theory framework describing trans-Planckian $2\to N$ graviton scattering. We construct a quantitative correspondence between a semi-classical Yang-Mills framework for radiation in gluon shockwave collisions and its counterpart in general relativity. In particular, we demonstrate the Lipatov double copy in a dilute-dilute approximation corresponding to $R_{S,L}$, $R_{S,H}$ $\ll b$, with $R_{S,L}$, $R_{S,H}$ the respective emergent Schwarzchild radii generated in shockwave collisions and $b$ is the impact parameter. We outline extensions of the correspondence developed here to the dilute-dense computation of gravitational wave radiation in close vicinity of one of the black holes, the construction of graviton propagators in the shockwave background, and a renormalization group approach to compute $2\to N$ amplitudes that incorporates graviton reggeization and coherent graviton multiple scattering.

    ↳ hep-thgr-qchep-phnucl-thPRD(2024)·14 citations
12. 12*

    Defying eternal inflation in warm inflation with a negative running

    Gabriele Montefalcone🇺🇸 · Rudnei O. Ramos🇧🇷 · Gustavo S. Vicente🇧🇷 · Katherine Freese🇺🇸

    It was pointed out previously~\cite{Kinney:2014jya} that a sufficiently negative running of the spectral index of curvature perturbations from (ordinary i.e. cold) inflation is able to prevent eternal inflation from ever occurring. Here, we reevaluate those original results, but in the context of warm inflation, in which a substantial radiation component (produced by the inflaton) exists throughout the inflationary period. We demonstrate that the same general requirements found in the context of ordinary (cold) inflation also hold true in warm inflation; indeed an even tinier amount of negative running is sufficient to prevent eternal inflation. This is particularly pertinent, as models featuring negative running are more generic in warm inflation scenarios. Finally, the condition for the existence of eternal inflation in cold inflation -- that the curvature perturbation amplitude exceed unity on superhorizon scales -- becomes more restrictive in the case of warm inflation. The curvature perturbations must be even larger, i.e. even farther out on the potential, away from the part of the potential where observables, e.g. in the Cosmic Microwave Background, are produced.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2024)·4 citations
13. 13*

    Chiral catalysis of nuclear fusion in molecules

    Dmitri E. Kharzeev🇺🇸 · Jake Levitt

    At low energies, nuclear fusion is strongly affected by electron screening of the Coulomb repulsion among the fusing nuclei. It may thus be possible to catalyze nuclear fusion in molecules (i.e., to fuse specific nuclei in situ) through quantum control of electron wave functions in intense laser fields. The circularly polarized (chiral) laser field can effectively squeeze the electron wave functions, greatly enhancing the screening in the spatial region relevant for the fusion process. We estimate the corresponding fusion probabilities, and find that the proposed chiral catalysis of nuclear fusion in molecules may be observable, potentially with important practical applications.

    ↳ nucl-thhep-phIJMPE(2024)·1 citation
14. 14*

    Describing the Thermal Radiation in $Au+Au$ Collisions at $\sqrt{s_{NN}}=$200 GeV by an Analytic Solution of Relativistic Hydrodynamics

    Gábor Kasza🇭🇺

    In high-energy heavy-ion collisions a nearly perfect fluid, the so-called strongly coupled quark gluon plasma forms. After the short period of thermalisation, the evolution of this medium can be described by the laws of relativistic hydrodynamics. The time evolution of the quark gluon plasma can be understood through direct photon spectra measurements, which are sensitive to the entire period between the thermalisation and the freeze-out of the medium. I present a new analytic formula that describes the thermal photon radiation and it is derived from an exact and finite solution of relativistic hydrodynamics with accelerating velocity field. Then I compare my calculations to the most recent nonprompt spectrum of direct photons for $Au+Au$ at $\sqrt{s_{NN}}=$200 GeV collisions. I have found a convincing agreement between the model and the data, which allows to give an estimate of the initial temperature in the center of the fireball. My results predict hydrodynamic scaling behaviour for the thermal photon spectra of high-energy heavy-ion collisions.

    ↳ nucl-thhep-phInt.J.Mod.Phys.A(2024)·4 citations
15. 15*

    Update on gravitational wave signals from post-inflationary phase transitions

    H. Kolesova🇳🇴 · M. Laine🇨🇭

    In view of recent interest in high-frequency detectors, broad features of gravitational wave signals from phase transitions taking place soon after inflation are summarized. The influence of the matter domination era that follows the slow-roll stage is quantified in terms of two equilibration rates. Turning to the highest-frequency part of the spectrum, we show how it is constrained by the fact that the bubble distance scale must exceed the mean free path.

    ↳ gr-qcastro-ph.COhep-phPLB(2024)·10 citations
16. 16*

    Chiral Soliton Lattice turns into 3D crystal

    Geraint W. Evans🇬🇧 · Andreas Schmitt🇬🇧

    Chiral perturbation theory predicts the chiral anomaly to induce a so-called Chiral Soliton Lattice at sufficiently large magnetic fields and baryon chemical potentials. This state breaks translational invariance in the direction of the magnetic field and was shown to be unstable with respect to charged pion condensation. Improving on previous work by considering a realistic pion mass, we employ methods from type-II superconductivity and construct a three-dimensional pion (and baryon) crystal perturbatively, close to the instability curve of the Chiral Soliton Lattice. We find an analogue of the usual type-I/type-II transition in superconductivity: Along the instability curve for magnetic fields $eB>0.12{\mathrm{GeV}}^2$ and chemical potentials $\mu <910\mathrm{MeV}$, this crystal can continuously supersede the Chiral Soliton Lattice. For smaller magnetic fields the instability curve must be preceded by a discontinuous transition.

    ↳ hep-thhep-phnucl-thJHEP(2024)·24 citations
17. 17*

    Search for high-frequency gravitational waves with Rydberg atoms

    Sugumi Kanno🇯🇵 · Jiro Soda🇯🇵 · Akira Taniguchi🇯🇵

    We propose high-frequency gravitational wave (GW) detectors with Rydberg atoms. Rydberg atoms are ultra-sensitive detectors of electric fields. By setting up a constant magnetic field, a weak electric field is generated upon the arrival of GWs. The weak electric field signal is then detected by an electromagnetically induced transparency (EIT) in the system of the Rydberg atoms. Recently, the minimum detectable electric field with the Rydberg atoms is further improved by employing superheterodyne detection method. Hence, even the weak signal generated by GWs turns out to be detectable. We calculate the amplitude of Rabi frequency of the Rydberg atoms induced by the GWs and show that the sensitivity of the Rydberg atoms becomes maximum when the size of the Rydberg atoms is close to the wavelength of GWs. We evaluate the minimum detectable amplitude of GWs with Rubidium Rydberg atoms and find that the detector can probe GWs with a frequency $f=4.2$ GHz and an amplitude around $10^{-20}$.

    ↳ gr-qchep-phhep-thphysics.atom-phEPJC(2025)·27 citations
18. 18*

    Study of the pion-mass dependence of $\rho$-meson properties in lattice QCD

    Kang Yu🇨🇳 · Yan Li🇨🇾 · Jia-Jun Wu🇨🇳 · Derek B. Leinweber🇦🇺 · Anthony W. Thomas🇦🇺

    We collect spectra extracted in the $I=\ell =1$ $\pi \pi$ sector provided by various lattice QCD collaborations and study the $m_{\pi }$ dependence of $\rho$-meson properties using Hamiltonian Effective Field Theory (HEFT). In this unified analysis, the coupling constant and cutoff mass, characterizing the $\rho -\pi \pi$ vertex, are both found to be weakly dependent on $m_{\pi }$, while the mass of the bare $\rho$, associated with a simple quark-model state, shows a linear dependence on $m_{\pi }^2$. Both the lattice results and experimental data can be described well. Drawing on HEFT's ability to describe the pion mass dependence of resonances in a single formalism, we map the dependence of the phase shift as a function of $m_{\pi }$, and expose interesting discrepancies in contemporary lattice QCD results.

    ↳ hep-lathep-phPRD(2024)·10 citations
19. 19*

    Estimate magnetic field strength in heavy-ion collisions via the direct photon elliptic flow

    Jing-An Sun🇨🇳 · Li Yan🇨🇳

    There must be electromagnetic fields created during high-energy heavy-ion collisions. As the quark-gluon plasma (QGP) starts to evolve hydrodynamically, although these fields may become weak comparing to the energy scales of the strong interaction, they are potentially important to some electromagnetic probes. In this work, we focus on the dissipative corrections in QGP due to the presence of a weak external magnetic field, and calculate accordingly the induced photon radiation in the framework of viscous hydrodynamics. By event-by-event hydrodynamical simulations, the experimentally measured direct photon elliptic flow can be well reproduced. Correspondingly, the direct photon elliptic flow implies a magnetic field strength around 0.1$m_{\pi }^2\sim 10^{16}$ G. This is indeed a weak field in heavy-ion physics that is compatible to the theoretical predictions, however, it is still an ultra-strong magnetic field in nature.

    ↳ nucl-thhep-phnucl-exPRC(2024)·20 citations
20. 20*

    Moment of inertia and supervortical temperature of gluon plasma

    Victor V. Braguta🇷🇺 · Maxim N. Chernodub🇫🇷 · Ilya E. Kudrov🇷🇺 · Artem A. Roenko🇷🇺 · Dmitrii A. Sychev🇷🇺

    Using lattice simulations, we analyze the influence of uniform rotation on the equation of state of gluodynamics. For a sufficiently slow rotation, the free energy of the system can be expanded into a series of powers of angular velocity. We calculate the moment of inertia given by the quadratic coefficient of this expansion using both analytic continuation and derivative methods, which demonstrate a good agreement between the results. We find that the moment of inertia unexpectedly takes a negative value below the ``supervortical temperature'' $T_s=1.50(10)T_c$, vanishes at $T=T_s$, and becomes a positive quantity at higher temperatures. We discuss how our results are related to the scale anomaly and the magnetic gluon condensate. We point out that the negativity of the moment of inertia is in qualitative agreement with our previous lattice calculations, indicating that the rigid rotation increases the critical temperatures in gluodynamics and QCD.

    ↳ hep-lathep-phhep-thPoS(2024)·7 citations
21. 21*

    Possible Impact of non-Gaussianities on cosmological constraints in neutrino physics

    Matteo Forconi🇮🇹 · Eleonora Di Valentino🇬🇧 · Alessandro Melchiorri🇮🇹 · Supriya Pan🇮🇳

    The search for non-Gaussian signatures in the Cosmic Microwave Background (CMB) is crucial for understanding the physics of the early Universe. Given the possibility of non-Gaussian fluctuations in the CMB, a recent revision to the standard $\Lambda$-Cold Dark Matter ($\Lambda$CDM) model has been proposed, dubbed "Super-$\Lambda$CDM". This model introduces additional free parameters to account for the potential effects of a trispectrum in the primordial fluctuations. In this study, we explore the impact of the Super-$\Lambda$CDM model on current constraints on neutrino physics. In agreement with previous research, our analysis reveals that for most of the datasets, the Super-$\Lambda$CDM parameter $A_0$ significantly deviates from zero at over a $95\%$ confidence level. We then demonstrate that this signal might influence current constraints in the neutrino sector. Specifically, we find that the current constraints on neutrino masses may be relaxed by over a factor of two within the Super-$\Lambda$CDM framework, thanks to the correlation present with $A_0$. Consequently, locking $A_0=0$ might introduce a bias, leading to overly stringent constraints on the total neutrino mass.

    ↳ astro-ph.COhep-phPRD(2024)·11 citations
22. 22*

    Revisiting Loop Corrections in Single Field USR Inflation

    Hassan Firouzjahi🇮🇷

    We revisit the one-loop corrections on CMB scale perturbations induced from small scale modes in single field models which undergo a phase of ultra slow-roll inflation. There were concerns that large loop corrections are against the notion of the decoupling of scales and they are cancelled out once the boundary terms are included in Hamiltonian. We highlight that the non-linear coupling between the long and short modes and the modulation of the short mode power spectrum by the long mode are the key physical reasons behind the large loop corrections. In particular, in order for the modulation by the long mode to be significant there should be a strong scale-dependent enhancement in power spectrum of the short mode which is the hallmark of the USR inflation. We highlight the important roles played by the would-be decaying mode which were not taken into account properly in recent works claiming the loop cancellation. We confirm the original conclusion that the loop corrections are genuine and they can be dangerous for PBHs formation unless the transition to the final attractor phase is mild.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2024)·62 citations
23. 23*

    Cosmic magnification in beyond-Horndeski gravity

    Didam Duniya (BIUST)🇧🇼 · Bishop Mongwane (Cape Town)🇿🇦

    Cosmic magnification is able to probe the geometry of large-scale structure on cosmological scales, thereby providing another window for probing theories of the late-time cosmic acceleration. It holds the potential to reveal new information on the nature of dark energy and modified gravity. By using the angular power spectrum, we investigated cosmic magnification beyond weak lensing (incorporating all known relativistic corrections) in beyond-Horndeski gravity$-$with both constant phenomenology and dynamic phenomenology, respectively. For both phenomenologies our results show that the total relativistic signal surpasses cosmic variance (considering an SKA2-like sky coverage) in the magnification angular power spectrum at low redshifts ($z\lesssim 0.5$), hence cosmic-variance reduction methods like multi-tracer analysis will not be needed for surveys at the given $z$. For the individual relativistic signals, we found that the Doppler magnification signal also surpasses cosmic variance and remains the dominant signal, at low $z$, for both phenomenologies. However, the integrated-Sachs-Wolfe, the time-delay, and the gravitational (potential) magnification signals, respectively, are subdominant to both the Doppler magnification signal and cosmic variance, at the same $z$; hence multi-tracer analysis will be needed to isolate these signals. At high redshifts ($z\gtrsim 3$), the integrated-Sachs-Wolfe, the time-delay, and the gravitational magnification signals, respectively, appear to surpass cosmic variance and dominate over the Doppler magnification signal for constant phenomenology; whereas for dynamic phenomenology, all these signals diminish significantly and are well below cosmic variance, at all $z$ (consistent with recent quintessence analysis). Suggesting that including time-variation in the parameters will be crucial in identifying the true signature of the beyond-Horndeski gravity.

    ↳ astro-ph.COgr-qchep-phJCAP(2025)·2 citations
24. 24*

    Elastic and resonance structures of the nucleon from hadronic tensor in lattice QCD: implications for neutrino-nucleon scattering and hadron physics

    Jian Liang🇨🇳 · Raza Sabbir Sufian🇺🇸 · Bigeng Wang🇺🇸 · Terrence Draper🇺🇸 · Tanjib Khan🇧🇩 · Keh-Fei Liu🇺🇸 · Yi-Bo Yang🇨🇳 · Christian Zimmermann🇺🇸

    We compute the Euclidean hadronic tensor from charge density operators and extract elastic and resonance structures by employing exponential fits to the four-point correlator, as well as a Bayesian reconstruction inverse algorithm to obtain the corresponding spectral density for qualitative comparison. We present the determination of the nucleon's Sachs electric form factor using the hadronic tensor formalism and verify that it is consistent with that from the conventional three-point function calculation. Beyond the elastic peak, we observe a structure located approximately $0.5-0.7$ GeV above the nucleon mass in the Bayesian reconstruction. The structure is interpreted as a mixture of the Roper resonance $(N(1440))$, and states with both positive and negative parities in this mass region, as well as multi-hadron states. Assuming the observed structure is dominated by $J^P=1/2^{\pm }$ states, we extract the transition electric form factor $G_E^{\ast }(Q^2)$ and the corresponding longitudinal helicity amplitude $S_{1/2}(Q^2)$, and compare them with those determined from the CLAS experimental data of nucleon-to-Roper transition. Although fitting to the four-point correlation function or using the inverse algorithm does not resolve individual resonances, it nevertheless enables the determination of total inclusive lepton-nucleon scattering cross sections in appropriate energy bins. This lattice QCD calculation presents the first major step toward studying the inclusive $N\to X$ contributions with the hadronic tensor formalism.

    ↳ hep-lathep-phnucl-thPRD(2026)·7 citations
25. 25*

    Fate of Chiral Symmetries in the Quark-Gluon Plasma from an Instanton-Based Random Matrix Model of QCD

    Tamas G. Kovacs (Eotvos U. and Debrecen, Inst. Nucl. Res.)🇭🇺

    We propose a new way of understanding how chiral symmetry is realized in the high temperature phase of QCD. Based on the finding that a simple free instanton gas precisely describes the details of the lowest part of the spectrum of the lattice overlap Dirac operator, we propose an instanton-based random matrix model of QCD with dynamical quarks. Simulations of this model reveal that even for small quark mass the Dirac spectral density has a singularity at the origin, caused by a dilute gas of free instantons. Even though the interaction, mediated by light dynamical quarks creates small instanton-antiinstanton molecules, those do not influence the singular part of the spectrum, and this singular part is shown to dominate Banks-Casher type sums in the chiral limit. By generalizing the Banks-Casher formula for the singular spectrum, we show that in the chiral limit the chiral condensate vanishes if there are at least two massless flavors. Our model also indicates a possible way of resolving a long-standing debate, as it suggests that for two massless quark flavors the $U(1{)}_A$ symmetry is likely to remain broken up to arbitrarily high finite temperatures.

    ↳ hep-lathep-phhep-thPRL(2024)·28 citations
26. 26*

    Binary systems in massive scalar-tensor theories: Next-to-leading order gravitational wave phase from effective field theory

    Robin Fynn Diedrichs🇩🇪 · Daniel Schmitt🇩🇪 · Laura Sagunski🇩🇪

    Neutron star binaries and their associated gravitational wave signal facilitate precision tests of General Relativity. Any deviation of the detected gravitational waveform from General Relativity would therefore be a smoking gun signature of new physics, in the form of additional forces, dark matter particles, or extra gravitational degrees of freedom. To be able to probe new theories, precise knowledge of the expected waveform is required. In our work, we consider a generic setup by augmenting General Relativity with an additional, massive scalar field. We then compute the inspiral dynamics of a binary system, for circular orbits, by employing an effective field theoretical approach, while giving a detailed introduction to the computational framework. Finally, we derive the modified TaylorF2 phase of the gravitational wave signal at next-to-leading order in the post-Newtonian expansion, and leading order in the parameters of the scalar sector, such as the scalar charge. As a consequence of our model-agnostic approach, our results are readily adaptable to a plethora of new physics scenarios, including modified gravity theories and scalar dark matter models.

    ↳ gr-qcastro-ph.COhep-phhep-thPRD(2024)·28 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.