Wed·Jan 31, 2024Wednesday·January 31, 2024

1. 01*

   Linear relation between short range correlation and EMC effect of gluons in nuclei

   Wei Wang🇨🇳 · Ji Xu🇨🇳 · Xing-Hua Yang🇨🇳 · Shuai Zhao🇨🇳

   We explore the EMC effect of gluons through heavy quark production in deep inelastic scattering (DIS) and the nucleon-nucleon short range correlation (SRC) from sub-threshold photoproduction of the $J/\psi$. Applying an effective field theory analysis, we scrutinize the gluon parton distribution functions in nuclear environment and propose a linear relation between the slope of reduced cross section ratio, which reflects the magnitude of gluon EMC effect, and the $J/\psi$ production cross section at the photon energy $E_{\gamma }=7.0\text{GeV}$ in the nucleus rest frame, a characteristic representative of SRC. This finding is supported by a numerical calculation using the available phenomenological results for gluon nuclear parton distribution functions (nPDFs). Examining this linear relation by the forthcoming experimental data on electron-ion collider allows to decipher nuclear effects of gluon distributions and enhance our comprehension of the substructure in bound nuclei.

   hep-phEPJA(2025)·7 citations
2. 02*

   Exploring quantum entanglement in chiral symmetry partial restoration with 1+1 string model

   Wei Kou🇨🇳 · Xurong Chen🇨🇳

   Within the confining color flux tube picture, we assess the color electric field generated by quark-antiquark pairs within the framework of the Schwinger model and estimate its impact on the chiral condensate. We observe differences in the distribution of the color flux tube generated by quark-antiquark pairs at different separation distances, leading to discrepancies in the partial restoration of chiral symmetry. Furthermore, we suggest incorporating the color magnetic field in the calculation of chiral condensate, leading to quantum entanglement effects, and proceed to compute the entanglement entropy. We observe that the entanglement entropy increases with the distance of the color source (the separation distance between quark and anti-quark), and the magnitude of the color electric field and chiral condensate restoration after spatial integration also increases with the distance of the color source. Then, we try to provide a qualitative explanation for the existence of these phenomena.

   hep-phPLB(2024)·3 citations
3. 03*

   Searching for Particle Dark Matter with eROSITA Early Data

   Chingam Fong🇨🇳 · Kenny C. Y. Ng🇨🇳 · Qishan Liu🇨🇳

   Many well motivated dark matter (DM) particle candidates can decay into detectable X-ray photons. We analyze the Final Equatorial Depth Survey (eFEDS) data from eROSITA early data release to search for unidentified X-ray lines that could indicate DM signals. Having discovered no anomalous signal, we set limits on DM decay rate in mass range between 1.8-18 keV, and constrain the parameter space of two DM particles: sterile neutrino and axion-like particles. Finally we also study the projected sensitivity of eROSITA full sky search, showing that eROSITA all-sky survey is expected to set the most stringent limits in the soft X-ray band.

   hep-phastro-ph.HEPRD(2025)·12 citations
4. 04*

   Revisiting series expansions of neutrino oscillation and decay probabilities in matter

   Jesper Grönroos🇸🇪 · Tommy Ohlsson🇸🇪 · Sampsa Vihonen🇸🇪

   We present analytic expressions for three-flavor neutrino oscillations in presence of invisible neutrino decay and matter effects. Using the well-known Cayley-Hamilton formalism, the leading-order terms are derived for oscillation probabilities in all major channels assuming the neutrino mass eigenstate ${\nu }_3$ to decay. Our work extends and complements previous studies utilizing the Cayley-Hamilton theorem, providing the series expansions for ${\nu }_e\to {\nu }_e$, ${\nu }_e\to {\nu }_{\mu }$, ${\nu }_e\to {\nu }_{\tau }$, ${\nu }_{\mu }\to {\nu }_{\mu }$ and ${\nu }_{\mu }\to {\nu }_{\tau }$. The accuracy of the analytical formulas is investigated by comparing the results with numerically calculated probabilities. We also comment on the implications on unitarity violation.

   hep-phhep-exhep-thPRD(2025)·7 citations
5. 05*

   A Simple Dirac Prescription for Two-Loop Anomalous Dimension Matrices

   Jason Aebischer🇨🇭 · Marko Pesut🇨🇭 · Zachary Polonsky🇨🇭

   A novel method to treat effects from evanescent operators in next-to-leading order (NLO) computations is introduced. The approach allows, besides further simplifications, to discard evanescent-to-physical mixing contributions in NLO calculations. The method is independent of the treatments of ${\gamma }_5$ and can therefore be combined with different renormalization schemes. We illustrate the utility of this result by reproducing literature results of two-loop anomalous dimension matrices for both $|\Delta F|=1$ and $|\Delta F|=2$ transitions.

   hep-phEPJC(2024)·17 citations
6. 06*

   Gauge and Scalar Boson Mediated Proton Decay in a Predictive SU(5) GUT Model

   Ilja Doršner🇭🇷 · Emina Džaferović-Mašić🇭🇷 · Svjetlana Fajfer🇸🇮 · Shaikh Saad🇨🇭

   We assess proton decay signatures in the simplest viable $SU(5)$ model with regard to constraints on parameters governing the Standard Model fermion mass spectrum. Experimental signals for all eight two-body proton decay processes result from exchange of two gauge bosons, a single scalar leptoquark, or their combination. Consequently, it enables us to delve into an in-depth anatomy of proton decay modes and anticipate future signatures. Our findings dictate that observing a proton decay into $p\to {\pi }^0{e}^{+}$ indicates gauge boson mediation, with the potential for observation of $p\to {\eta }^0{e}^{+}$ mode. Alternatively, if decay is through $p\to K^{+}\overline{\nu }$ process, it is mediated by a scalar leptoquark, possibly allowing the observation of $p\to {\pi }^0{\mu }^{+}$. Detection of both $p\to {\pi }^0{e}^{+}$ and $p\to K^{+}\overline{\nu }$ could enhance $p\to {\pi }^0{\mu }^{+}$ through constructive interference. The model predicts inaccessibility of $p\to {\pi }^{+}\overline{\nu }$, $p\to {\eta }^0{\mu }^{+}$, $p\to K^0{e}^{+}$, and $p\to K^0{\mu }^{+}$, regardless of the dominant mediation type, in the coming decades. In summary, through a comprehensive analysis of proton decay signals, gauge coupling unification, and fermion masses and mixing, we precisely constrain the parameter space of the $SU(5)$ model in question.

   hep-phPRD(2024)·11 citations
7. 07*

   Comment on "Axion Electrodynamics in the Presence of Current Sources"

   Thomas Schwetz🇩🇪 · Elisa Todarello🇮🇹

   In this note we refute the critique raised in a preprint by J.~Berger and A.~Bhoonah~\cite{Berger:2023muj} on the method used in our earlier paper, Beutter et al.~\cite{Beutter:2018xfx}, to calculate the electromagnetic fields induced by an axion background in the presence of a magnetic field.

   hep-ph0 citations
8. 08*

   disorder: Deep inelastic scattering at high orders

   Alexander Karlberg🇨🇭

   We present a Fortran 77/95 code capable of computing QCD corrections in deep inelastic scattering (DIS). The code uses the Projection-to-Born method to augment an existing $\mathcal{O}({\alpha }_s^2)$ dijet DIS code, thereby obtaining predictions for photon-mediated neutral-current single-jet DIS production in the laboratory frame. The code is lightweight and fast, and yet includes the most common functionalities found in typical perturbative QCD programs, like automatic renormalisation and factorisation scale uncertainties, options to run and combine multiple seeds, and interfaces to fastjet and LHAPDF. Due to the underlying disent and HOPPET codes, the program also provides stable results in the infrared, relevant for extracting logarithmic coefficients for analytic resummations, and access to the massless DIS structure functions and (reduced) cross sections up to $\mathcal{O}({\alpha }_s^3)$.

   hep-phhep-exSciPost Phys.Codeb.(2024)·9 citations
9. 09*

   Asymmetric pulse effects on pair production in chirped electric fields

   Neng-Zhi Chen🇨🇳 · Orkash Amat🇨🇳 · Li-Na Hu🇨🇳 · Hong-Hao Fan🇨🇳 · Bai-Song Xie🇨🇳

   We investigate the effects of the asymmetric pulse shapes on electron-positron pair production in three distinct fields: chirp-free, small frequency chirp, and large frequency chirp fields via the real-time Dirac-Heisenberg-Wigner formalism. Our findings reveal the disappearance of interference effects with shorter falling pulse length, and the peak is concentrated on the left side of the momentum spectrum. As the falling pulse length extends, an incomplete multi-ring structure appears in the momentum spectrum. The number density of particles are very sensitive to the asymmetry of the pulse. With a long falling pulse, the number density can be significantly enhanced by over four orders of magnitude when certain frequency chirps are utilized. These results highlight the impact of the effective dynamically assisted mechanism and the frequency chirp on pair creation.

   hep-phquant-phPRD(2024)·13 citations
10. 10*

    Ultralight scalar and axion dark matter detection with atom interferometers

    Wei Zhao🇨🇳 · Hui Liu🇨🇳 · Xitong Mei🇨🇳

    The detection of dark matter is a challenging problem in modern physics. The ultralight scalar and axion dark matter could induce the oscillation of the nuclear charge radii and then oscillate the atomic transition frequency by interacting with standard model particles. We compute the differential phase shift caused by the scalar and axion dark matter in a pair of separated atom interferometers and give the proposed constraints on the scalar dark matter coupling parameters $d_g$ and $d_{\hat{m}}$ as well as the axion dark matter coupling parameter $1/f_a$. Our results are expected to improve the current detection level and complement with other experiments.

    hep-phChin.Phys.Lett.(2024)·3 citations
11. 11*

    Coherent ${\gamma }^{\ast }$-nucleus scattering and coherent nuclear states

    Alfred H. Mueller🇺🇸

    In the context of a McLerran-Venugopalan (MV) model for a large nucleus, coherent scattering of a virtual photon on that nucleus is evaluated in the $A_{-}=0$ gauge, the gauge appropriate for the target nucleus. The evaluation of the scattering in $A_{-}=0$ gauge is very intricate compared to the usual $A_{+}=0$ gauge evaluation natural for the scattering process, but has the advantage of directly giving the scattering in terms of a partonic description of the nucleus. In the limit where a tagged forward jet puts the dipole-nucleus scattering in the saturation regime the coherent reactions are equal to the inelastic reactions. In terms of the nuclear wave function the coherent reactions come from color singlet and zero total transverse momentum quark-antiquark pairs in the wave function and in the saturation regime the nuclear wave function is a coherent state for these pairs. In the saturation region half of all quarks (or antiquarks) come from zero momentum and color charge pairs.

    hep-phnucl-thJHEP(2024)·3 citations
12. 12*

    Heavy flavour hadron production in relativistic heavy ion collisions at RHIC and LHC in EPOS4HQ

    Jiaxing Zhao🇫🇷 · Joerg Aichelin🇫🇷 · Pol Bernard Gossiaux🇫🇷 · Vitalii Ozvenchuk🇵🇱 · Klaus Werner🇫🇷

    Employing the recently developed EPOS4HQ event generator, we study the production of different heavy-flavor mesons in relativistic heavy-ion collisions at RHIC and LHC energies. The transverse momentum spectra, yield ratio, nuclear modification factor, and elliptic flow can be well described in the EPOS4HQ framework. We furthermore analyze the processes which modify these observables as compared to $pp$ collisions and are at the origin of the experimentally determined nuclear modification factor $R_{AA}$.

    hep-phnucl-thPRC(2024)·32 citations
13. 13*

    Estimating the strong coupling from $\tau$ decay using accelerating series convergence

    K. Schilcher🇿🇦 · C. Sebu🇲🇹 · H. Spiesberger🇩🇪

    We apply the Euler transformation to accelerate the convergence of the QCD perturbative series with the aim to determine the strong coupling ${\alpha }_s$ in terms of the total $\tau$-decay rate $r_{\tau }$. The variation of the result with the order of the QCD perturbation theory is small and comparable with the uncertainties of $r_{\tau }$. We also present an estimate of a range of the yet unknown 5th and 6th order coefficients $k_5$ and $k_6$ of the Adler function.

    hep-phPLB(2024)·2 citations
14. 14*

    Diffractive deep inelastic scattering at NLO in the dipole picture

    Guillaume Beuf🇵🇱 · Tuomas Lappi🇫🇮 · Heikki Mäntysaari🇫🇮 · Risto Paatelainen🇫🇮 · Jani Penttala🇺🇸

    We compute the transverse and longitudinal diffractive structure functions to full next-to-leading order accuracy in the dipole picture of deep inelastic scattering. Our calculation uses the standard light-cone perturbation theory method for the partonic content of the virtual photon, together with the Color Glass Condensate description of the target color field. Our result includes as a subset the $q\bar{q}g$ contribution calculated earlier. We show that there is a rapidity divergence that can be factorized into the BK/JIMWLK evolution of the target Wilson lines, and that all other divergences cancel.

    hep-phnucl-thJHEP(2024)·28 citations
15. 15*

    Spectrum of global string networks and the axion dark matter mass

    Ken'ichi Saikawa🇯🇵 · Javier Redondo🇪🇸 · Alejandro Vaquero🇪🇸 · Mathieu Kaltschmidt🇪🇸

    Cold dark matter axions produced in the post-inflationary Peccei-Quinn symmetry breaking scenario serve as clear targets for their experimental detection, since it is in principle possible to give a sharp prediction for their mass once we understand precisely how they are produced from the decay of global cosmic strings in the early Universe. In this paper, we perform a dedicated analysis of the spectrum of axions radiated from strings based on large scale numerical simulations of the cosmological evolution of the Peccei-Quinn field on a static lattice. Making full use of the massively parallel code and computing resources, we executed the simulations with up to $11264^3$ lattice sites, which allows us to improve our understanding of the dependence on the parameter controlling the string tension and thus give a more accurate extrapolation of the numerical results. We found that there are several systematic effects that have been overlooked in previous works, such as the dependence on the initial conditions, contaminations due to oscillations in the spectrum, and discretisation effects, some of which could explain the discrepancy in the literature. We confirmed the trend that the spectral index of the axion emission spectrum increases with the string tension, but did not find a clear evidence of whether it continues to increase or saturates to a constant at larger values of the string tension due to the severe discretisation effects. Taking this uncertainty into account and performing the extrapolation with a simple power law assumption on the spectrum, we find that the dark matter mass is predicted in the range of $m_a\approx 95$-$450\mu \mathrm{eV}$.

    hep-phastro-ph.COJCAP(2024)·106 citations
16. 16*

    Scalable Dark Matter Searches Using Integrated Photonics

    Nikita Blinov🇨🇦 · Christina Gao🇨🇳 · Roni Harnik🇺🇸 · Ryan Janish🇺🇸 · Neil Sinclair🇺🇸

    Dark matter (DM) with masses of order an electronvolt or below can have a non-zero coupling to electromagnetism while being compatible with cosmological observations. In these models, the ambient DM behaves as a new classical source in Maxwell's equations, which can excite potentially detectable electromagnetic (EM) fields in the laboratory. We propose a new integrated photonics-based approach to search for DM candidates in the 0.1 - few eV mass range. This approach offers a wide range of wavelength-scale devices like resonators and waveguides that are readily fabricated in large quantities, enabling a scalable and novel search. In particular, we demonstrate that refractive index-modulated resonators, such as etched/grooved microrings, or patterned slabs, support EM modes with efficient coupling to DM. When excited by DM, these modes are read out by coupling the resonators to a waveguide that terminates on a micron-scale-sized single photon detector, such as a single pixel of a low-noise charge-coupled device or a superconducting nanowire. We then estimate the sensitivity of this experimental concept in the context of axion-like particle and dark photon models of DM, demonstrating that nanophotonic confinement and scalability can extend dark matter sensitivity into previously unexplored parameter space.

    hep-phphysics.opticsquant-phPRD(2026)·5 citations
17. 17*

    Polarized ZZ pairs in gluon fusion and vector boson fusion at the LHC

    Martina Javurkova🇺🇸 · Richard Ruiz🇵🇱 · Rafael Coelho Lopes de Sá🇺🇸 · Jay Sandesara🇺🇸

    Pair production of helicity-polarized weak bosons $(V_{\lambda }=W_{\lambda }^{\pm },Z_{\lambda })$ from gluon fusion $(gg\to V_{\lambda }{V}_{{\lambda }^{\prime }}^{\prime })$ and weak boson fusion $(V_1{V}_2\to V_{\lambda }{V}_{{\lambda }^{\prime }}^{\prime })$ are powerful probes of the Standard Model, new physics, and properties of quantum systems. Measuring cross sections of polarized processes is a chief objective of the Large Hadron Collider's (LHC) Run 3 and high luminosity programs, but progress is limited by the simulation tools that are presently available. We propose a method for computing polarized cross sections that works by directly modifying Feynman rules instead of (squared) amplitudes. The method is applicable to loop-induced processes, and can capture the interference between arbitrary polarization configurations, interference with non-resonant diagrams, as well as off-shell/finite-width effects. By construction, previous results that work at the (squared) amplitude level are recoverable. As a demonstration, we report the prospect of observing and studying polarized $Z_{\lambda }{Z}_{{\lambda }^{\prime }}$ pairs when produced via gluon fusion and electroweak processes in final-states with four charged leptons at the LHC, using the new method to simulate the gluon fusion process. Our Feynman rules are publicly available as a set of \textit{Universal FeynRules Object} libraries called \texttt{SM\_Loop\_VPolar}.

    hep-phhep-exPLB(2024)·24 citations
18. 18*

    Dark Matter production during Warm Inflation via Freeze-In

    Katherine Freese🇺🇸 · Gabriele Montefalcone🇺🇸 · Barmak Shams Es Haghi🇺🇸

    We present a novel perspective on the role of inflation in the production of Dark Matter (DM). Specifically, we explore the DM production during Warm Inflation via ultraviolet Freeze-In (WIFI). We demonstrate that in a Warm Inflation (WI) setting the persistent thermal bath, sustained by the dissipative interactions with the inflaton field, can source a sizable DM abundance via the non-renormalizable interactions that connect the DM with the bath. Compared to the (conventional) radiation-dominated (RD) UV freeze-in scenario for the same reheat temperature (after inflation), the resulting DM yield in WIFI is always enhanced showing a strongly positive dependence on the mass dimension of the non-renormalizable operator. Of particular interest, for a sufficiently large mass dimension of the operator, the entirety of the DM abundance of the Universe can be created during the inflationary phase. For the specific models we study, we find that the enhancement in DM yield, relative to RD UV freeze-in, is at least an order of magnitude for an operator of mass dimension 5, and as large as 18 order of magnitudes for an operator of mass dimension 10. Our findings also suggest a broader applicability for producing other cosmological relics, which may have a substantial impact on the evolution of the early Universe.

    hep-phastro-ph.COgr-qchep-thPRL(2024)·19 citations
19. 19*

    Isovector Axial Charge and Form Factors of Nucleons from Lattice QCD

    Rajan Gupta🇺🇸

    I present an overview of the calculations of the isovector axial vector form factor of the nucleon, $G_A(Q^2)$, using lattice QCD. Based on a comparison of results from various collaborations, a case is made that lattice results are now consistent within 10\%. A similar level of uncertainty is found also in the axial charge $g_A^{u-d}$, the mean squared axial charge radius, $⟨r_A^2⟩$, the induced pseudoscalar charge $g_P^{\ast }$, and the pion-nucleon coupling $g_{\pi NN}$. These lattice results for $G_A(Q^2)$ are already compatible with those obtained from the recent MINER$\nu$A experiment but lie 2-3$\sigma$ higher than the phenomenological extraction from the old $\nu$-deuterium bubble chamber scattering data for $Q^2>0.3$~GeV${}^2$. Fits to our data show that the dipole ansatz does not have enough parameters to parameterize the form factor over the range $0\le Q^2\le 1$~GeV${}^2$, whereas even a $z^2$ truncation of the $z$-expansion or a low order Padé are sufficient. Looking ahead, lattice QCD calculations will provide increasingly precise results over the range $0\le Q^2\lesssim 1$~GeV${}^2$, and MINER$\nu$A-like experiments will extend the range to $Q^2\sim 2$~GeV${}^2$ or higher. To increase precision of lattice data to the percent level, new developments are needed to address two related issues: the exponentially falling signal-to-noise ratio in all nucleon correlation functions and removing excited state contributions. Nevertheless, even with the current methodology, significant reduction in errors is expected over the next few years with higher statistics data on more ensembles closer to the physical point.

    ↳ hep-lathep-phnucl-thUniverse(2024)·13 citations
20. 20*

    Bottomonium suppression in 5.02 and 8.16 TeV p-Pb collisions

    Michael Strickland🇺🇸 · Sabin Thapa🇺🇸 · Ramona Vogt🇺🇸

    We compute the suppression of Upsilon(1S), Upsilon(2S), and Upsilon(3S) states in p-Pb collisions relative to pp collisions, including nuclear parton distribution function (nPDF) effects, coherent energy loss, momentum broadening, and final-state interactions in the quark-gluon plasma. We employ the EPPS21 nPDFs and calculate the uncertainty resulting from variation over the associated error sets. To compute coherent energy loss and momentum broadening, we follow the approach of Arleo, Peigne, and collaborators. The 3+1D viscous hydrodynamical background evolution of the quark-gluon plasma is generated by anisotropic hydrodynamics. The in-medium suppression of bottomonium in the quark-gluon plasma is computed using a next-to-leading-order open quantum system framework formulated within potential nonrelativistic quantum chromodynamics. We find that inclusion of all these effects provides a reasonable description of experimental data from the ALICE, ATLAS, CMS, and LHCb collaborations for the suppression of Upsilon(1S), Upsilon(2S), and Upsilon(3S) as a function of both transverse momentum and rapidity.

    ↳ nucl-thhep-phPRD(2024)·11 citations
21. 21*

    Photon-triggered jets as probes of multi-stage jet modification

    C. Sirimanna🇺🇸 · Y. Tachibana🇯🇵 · A. Angerami🇺🇸 · R. Arora🇺🇸 · S. A. Bass🇺🇸 · S. Cao🇨🇳 · Y. Chen🇺🇸 · L. Du🇨🇦 · R. Ehlers🇺🇸 · H. Elfner🇩🇪 · W. Fan🇺🇸 · R. J. Fries🇺🇸 and 41 other authors

    Prompt photons are created in the early stages of heavy ion collisions and traverse the QGP medium without any interaction. Therefore, photon-triggered jets can be used to study the jet quenching in the QGP medium. In this work, photon-triggered jets are studied through different jet and jet substructure observables for different collision systems and energies using the JETSCAPE framework. Since the multistage evolution used in the JETSCAPE framework is adequate to describe a wide range of experimental observables simultaneously using the same parameter tune, we use the same parameters tuned for jet and leading hadron studies. The same isolation criteria used in the experimental analysis are used to identify prompt photons for better comparison. For the first time, high-accuracy JETSCAPE results are compared with multi-energy LHC and RHIC measurements to better understand the deviations observed in prior studies. This study highlights the importance of multistage evolution for the simultaneous description of experimental observables through different collision systems and energies using a single parameter tune.

    ↳ nucl-thhep-phEPJ Web Conf.(2024)·2 citations
22. 22*

    Post-inflationary Leptogenesis and Dark Matter production: Metric versus Palatini formalism

    Anish Ghoshal🇵🇱 · Zygmunt Lalak🇵🇱 · Supratik Pal🇮🇳 · Shiladitya Porey🇷🇺

    We investigate production of non-thermal dark matter particles and heavy sterile neutrinos from inflaton during the reheating era, which is preceded by a slow-roll inflationary epoch with a quartic potential and non-minimal coupling ($\xi$) between inflaton and gravity. We compare our analysis between metric and Palatini formalism. For the latter, the tensor-to-scalar ratio, r, decreases with $\xi$. We find that for $\xi =0.5$ and number of $e$-folds $\sim 60$, $r$ can be as small as $\sim \mathcal{O}\left(10^{-3}\right)$ which may be validated at future reaches of upcoming CMB observation such as CMB-S4 etc. We identify the permissible range of Yukawa coupling $y_{\chi }$ between inflaton and fermionic DM $\chi$, to be $\mathcal{O}\left(10^{-3.5}\right)\gtrsim y_{\chi }\gtrsim \mathcal{O}\left(10^{-20}\right)$ for metric formalism and $\mathcal{O}\left(10^{-4}\right)\gtrsim y_{\chi }\gtrsim \mathcal{O}\left(10^{-11}\right)$ for Palatini formalism which is consistent with current PLANCK data and also within the reach of future CMB experiments. For the scenario of leptogenesis via the decay of sterile neutrinos produced from inflaton decay, we also investigate the parameter space involving heavy neutrino mass $M_{N_1}$ and Yukawa coupling $y_{N_1}$ of sterile neutrino with inflaton, which are consistent with current CMB data and successful generation of the observed baryon asymmetry of the universe via leptogenesis. In contrast to metric formalism, in the case of Palatini formalism, for successful leptogenesis to occur, we find that $y_{N_1}$ has a very narrow allowable range and is severely constrained from the consistency with CMB predictions.

    ↳ astro-ph.COhep-phhep-thJHEP(2024)·7 citations
23. 23*

    Axion Theory and Model Building

    Kiwoon Choi🇰🇷 · Nicole Righi🇬🇧

    Axions are light pseudoscalar bosons postulated with many motivations in particle physics and cosmology, including the strong CP problem and the dark matter in our Universe. In this lecture notes, we discuss a variety of known ultraviolet (UV) theories for axions and their low energy properties. We are primarily concerned with the quantum chromodynamics axion solving the strong CP problem, as well as lighter axion-like particles. In regard to their UV origin, such light axions may arise from the spontaneous breakdown of a linearly realized global Peccei-Quinn U(1) symmetry in the context of 4-dimensional effective field theories, or they may originate from a gauge field in higher dimensional theories. It is noted that different UV models for these axions predict a distinctive pattern of low energy axion couplings, which may have interesting implications for laboratory, astrophysical, or cosmological studies of axions. We also provide an introductory discussion of the effective field theory for axions from p-form gauge fields in string theory with concrete examples.

    ↳ hep-thastro-ph.COhep-phPoS(2024)·12 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.