Fri·Apr 14, 2023Friday·April 14, 2023

1. 01*

   Energetic long-lived particles in the CMS muon chambers

   Andrea Mitridate🇩🇪 · Michele Papucci🇺🇸 · Christina Wang🇺🇸 · Cristián Peña🇺🇸 · Si Xie🇺🇸

   We present a recast in different benchmark models of the recent CMS search that uses the endcap muon detector system to identify displaced showers produced by decays of long-lived particles (LLPs). The exceptional shielding provided by the steel between the stations of the muon system drastically reduces the Standard Model background that limits other existing ATLAS and CMS searches. At the same time, by using the muon system as a sampling calorimeter, the search is sensitive to LLPs energies rather than masses. We show that, thanks to these characteristics, this new search approach is sensitive to LLPs masses even lighter than a GeV, and can be complementary to proposed and existing dedicated LLP experiments.

   hep-phhep-exPRD(2023)·21 citations
2. 02*

   Analytic Solution for the Revised Helicity Evolution at Small $x$ and Large $N_c$: New Resummed Gluon-Gluon Polarized Anomalous Dimension and Intercept

   Jeremy Borden🇺🇸 · Yuri V. Kovchegov🇺🇸

   We construct an exact analytic solution of the revised small-$x$ helicity evolution equations derived recently. The equations we solve are obtained in the large-$N_c$ limit (with $N_c$ the number of quark colors) and are double-logarithmic (summing powers of ${\alpha }_s{\ln }^2(1/x)$ with ${\alpha }_s$ the strong coupling constant and $x$ the Bjorken $x$ variable). Our solution provides small-$x$, large-$N_c$ expressions for the flavor-singlet quark and gluon helicity parton distribution functions (PDFs) and for the $g_1$ structure function, with their leading small-$x$ asymptotics given by \begin{align} \Delta \Sigma (x, Q^2) \sim \Delta G (x, Q^2) \sim g_1 (x, Q^2) \sim \left( \frac{1}{x} \right)^{\alpha_h} , \notag \end{align} where the exact analytic expression we obtain for the intercept ${\alpha }_h$ can be approximated by ${\alpha }_h=3.66074\sqrt{\frac{{\alpha }_s{N}_c}{2\pi }}$. Our solution also yields an all-order (in ${\alpha }_s$) resummed small-$x$ anomalous dimension $\Delta {\gamma }_{GG}(\omega )$ which agrees with all the existing fixed-order calculations (to three loops). Notably, our anomalous dimension is different from that obtained in the infrared evolution equation framework developed earlier by Bartels, Ermolaev, and Ryskin (BER), with the disagreement starting at four loops. Despite the previously reported agreement at two decimal points based on the numerical solution of the same equations, the intercept of our large-$N_c$ helicity evolution and that of BER disagree beyond that precision, with the BER intercept at large $N_c$ given by a different analytic expression from ours with the numerical value of ${\alpha }_h^{BER}=3.66394\sqrt{\frac{{\alpha }_s{N}_c}{2\pi }}$. We speculate on the origin of this disagreement.

   hep-phnucl-thPRD(2023)·41 citations
3. 03*

   Mass spectrum of $1^{--}$ heavy quarkonium

   Zheng Zhao🇹🇭 · Kai Xu🇹🇭 · Ayut Limphirat🇹🇭 · Warintorn Sreethawong🇹🇭 · Nattapat Tagsinsit🇹🇭 · Attaphon Kaewsnod🇹🇭 · Xuyang Liu🇹🇭 · Khanchai Khosonthongkee🇹🇭 · Sampart Cheedket🇹🇭 · Yupeng Yan🇹🇭

   We calculate the masses and leptonic decay widths of the bottomonium $b\bar{b}$ and charmonium $c\bar{c}$ states in a constituent quark model where the Cornell-like potential and spin-dependent interaction are employed, with all model parameters predetermined by studying ground and first radial excited states of S- and P-wave heavy quarkonium mesons. By comparing the theoretical predictions for $J^{PC}=1^{--}$ quarkonium states with experimental data and considering possible mixtures of $nS$ and $(n-1)D$ states, we provide tentative assignments for all observed $J^{PC}=1^{--}$ heavy quarkonia. The work suggests that the ${\rm Y}$(10860) and ${\rm Y}$(11020) are $b\bar{b}$ $5S-4D$ mixture states, and the $\psi$(4360) and $\psi$(4415) are largely $4S$ and $3D$ $c\bar{c}$ states respectively. The $\psi$(4260) may not be accommodated with the conventional meson picture in the present work.

   hep-phPRD(2024)·19 citations
4. 04*

   Neutrino Mass in Non-Supersymmetric $SO(10)$ GUT

   Naoyuki Haba🇯🇵 · Yasuhiro Shimizu🇯🇵 · Toshifumi Yamada🇯🇵

   We study a prediction on neutrino observables in a non-supersymmetric renormalizable $SO(10)$ GUT model that contains a $10$ complex scalar field and a $126$ scalar field whose Yukawa couplings with $16$ matter fields provide the quark and charged lepton Yukawa couplings, neutrino Dirac Yukawa coupling and Majorana mass for the singlet neutrinos. The $SO(10)$ breaking is achieved in two steps by a $\mathcal{O}(10^{15})$ GeV VEV of a $54$ real scalar field and a $\mathcal{O}(10^{14})$ GeV VEV of the $126$ field. First, we analyze the gauge coupling unification conditions and determine the VEV of the $126$ field. Next, we constrain the Yukawa couplings of the $10$ and $126$ fields at the scale of the $126$ field's VEV from experimental data on quark and charged lepton masses and quark flavor mixings. Then we express the active neutrino mass with the above Yukawa couplings and the $126$ field's VEV based on the Type-1 seesaw mechanism, and fit neutrino oscillation data, thereby deriving a prediction on poorly or not measured neutrino observables. What distinguishes our work from previous studies is that we do not assign Peccei-Quinn charges on visible sector fields so that the $10$ scalar field and its complex conjugate both have Yukawa couplings with $16$ matter fields. From the fitting of neutrino oscillation data, we find that not only the normal neutrino mass hierarchy, but also the inverted hierarchy can be realized. We also reveal that in the normal hierarchy case, the Dirac CP phase of the neutrino mixing matrix ${\delta }_{CP}$ is likely in the ranges of $-2.4<{\delta }_{\mathrm{CP}}<-1.2$ and $1.2<{\delta }_{\mathrm{CP}}<2.4$, and not in the region with ${\delta }_{\mathrm{CP}}\sim \pi$, and that in the normal hierarchy case, ${\theta }_{23}$ is likely in the upper octant and in the range of $0.50\lesssim {\sin }^2{\theta }_{23}\lesssim 0.55$.

   hep-phPRD(2023)·10 citations
5. 05*

   Testing electroweak scale seesaw models at $e^{-}\gamma$ and $\gamma \gamma$ colliders

   Arindam Das🇯🇵 · Sanjoy Mandal🇰🇷 · Sujay Shil🇧🇷

   We investigate the possibilities of probing the electroweak scale seesaw scenarios such as type-I, type-II and type-III seesaw at $e^{-}\gamma$ and $\gamma \gamma$ colliders. For the case of type-I seesaw, the heavy neutrinos can be produced at $e^{-}\gamma$ colliders in association with a $W$ boson. We study a variety of final states in this case including single and multilepton modes in association with jets to estimate bounds on the light-heavy neutrino mixing angle. In case of type-II seesaw, doubly charged multiplets of the SU$(2{)}_L$ triplet scalar can be produced in pair at $\gamma \gamma$ collider. We study the multi-leptonic decay modes coming from this pair production of doubly charged Higgs and show how one can probe neutrino mass hierarchy. We also study same sign $W$ boson production from the doubly charged Higgs to study multilepton modes in association with missing energy. From the type-III seesaw, we study same sign dilepton+jets and trilepton+jets modes at $e^{-}\gamma$ collider which are coming from the neutral and charged component of the triplet fermion in association with a $W$ boson and $Z$ boson, respectively. Due to the existing limits on the triplet fermions from the LHC we choose heavier mass so that the gauge boson originated from the decay of a neutral multiplet can be sufficiently boosted producing a fat-jet signature in association with same sign dilepton and trilepton. Finally we estimate bounds on the light neutrino-heavy triplet fermion mixing angle and compare with the existing bounds.

   hep-phhep-exPRD(2023)·26 citations
6. 06*

   Bayesian inference of the path-length dependence of jet energy loss

   Jordan Wu🇨🇳 · Weiyao Ke🇺🇸 · Xin-Nian Wang🇺🇸

   A simple model for medium modification of the jet function can be used to extract the jet energy loss distribution through a parameterized form. We carry out a comprehensive Bayesian analysis of the world data on single inclusive jet spectra in heavy-ion collisions at both RHIC and LHC energies. We extract the average jet energy loss $⟨\Delta E⟩$ as a function of jet transverse momentum $p_T$ for each collision system and centrality independently. Assuming jet energy loss is proportional to the initial parton density $\rho \sim d{N}_{\mathrm{ch}}/d\eta /\pi R_{\mathrm{eff}}^2$ as estimated from the pseudorapidity density of charged hadron multiplicity $d{N}_{\mathrm{ch}}/d\eta$ and the effective system size $R_{\mathrm{eff}}\sim N_{\mathrm{part}}^{1/3}$ given by the number of participant nucleons $N_{\mathrm{part}}$, the scaled average jet energy loss $⟨\Delta E⟩/\rho \sim R_{\mathrm{eff}}^{0.59}{p}_T^{0.13}\ln p_T$ for jet cone-size $R=0.4$ is found to have a momentum dependence that is slightly stronger than a logarithmic form while the system size or length dependence is slower than a linear one. The fluctuation of jet energy loss is, however, independent of the initial parton density or the system size.

   hep-phnucl-thPRC(2023)·17 citations
7. 07*

   Kinematical higher-twist corrections in ${\gamma }^{\ast }\to M_1{M}_2\gamma$: Neutral meson production

   Bernard Pire🇫🇷 · Qin-Tao Song🇨🇳

   We carry out the calculation of kinematical higher-twist corrections to the cross section of ${\gamma }^{\ast }\to M_1{M}_2\gamma$ up to twist 4, where $M_i$ is a scalar or pseudoscalar neutral meson. The three independant helicity amplitudes are presented in terms of the twist-2 generalized distribution amplitudes (GDAs), which are important non-perturbative quantities for understanding the 3D structure of hadrons. Since this process can be measured by BESIII in $e^{+}{e}^{-}$ collisions, we perform the numerical estimate of the kinematical higher-twist corrections by using the kinematics of BESIII. We adopt the $\pi \pi$ GDA extracted from Belle measurements and the asymptotic $\pi \pi$ GDA to study the size of the kinematical corrections in the case of pion meson pair, and a model $\eta \eta$ GDA is used to see the impact of target mass corrections $\mathcal{O}(m^2/s)$ for ${\gamma }^{\ast }\to \eta \eta \gamma$. Our results show that the kinematical higher-twist corrections account for $\sim 20\%$ of the cross sections at BESIII on the average, and it is necessary to include them if one tries to extract GDAs from experimental measurements precisely. We also comment the case of ${\pi }^0\eta$ production which is important for the search of hybrid mesons.

   hep-phhep-exnucl-exnucl-thPRD(2023)·9 citations
8. 08*

   Anisotropic flow and the valence quark skeleton of hadrons

   Meijian Li🇪🇸 · Wenyang Qian🇪🇸 · Bin Wu🇪🇸 · Hong Zhang🇨🇳

   We study transverse momentum anisotropies, in particular, the elliptic flow $v_2$ due to the interference effect sourced by valence quarks in high-energy hadron-hadron collisions. Our main formula is derived as the high-energy (eikonal) limit of the impact-parameter dependent cross section in quantum field theory, which agrees with that in terms of the impact parameter in the classical picture. As a quantitative assessment of the interference effect, we calculate $v_2$ in the azimuthal distribution of gluons at a comprehensive coverage of the impact parameter and the transverse momentum in high-energy pion-pion collisions. In a broad range of the impact parameter, a sizable amount of $v_2$, comparable with that produced due to saturated dense gluons or final-state interactions, is found to develop. In our calculations, the valence sector of the pion wave function is obtained numerically from the Basis Light-Front Quantization, a non-perturbative light-front Hamiltonian approach. And our formalism is generic and can be applied to other small collision systems like proton-proton collisions.

   hep-phnucl-thJHEP(2023)·4 citations
9. 09*

   Constraints on new physics around the MeV scale with cosmological observations

   Shihao Deng🇨🇳 · Ligong Bian🇨🇳

   We investigate the joint effect of the cosmological phase transitions, thermal light dark matter, and the lepton asymmetry on the big bang nucleosynthesis and cosmic microwave background. We find that all of them can modify the predictions of the effective number of neutrino species and primordial nucleosynthesis. In turn, we observe that: 1) the cosmological observations can exclude slow and strong phase transitions with strength even smaller than $\mathcal{O}(10^{-3}-10^{-2})$; 2) a much larger portion of dark matter mass region is excluded when the phase transition temperature is closer to 1 MeV; and 3) the magnitude of the non-vanishing neutrino lepton asymmetry is limited to be around $\mathcal{O}(10^{-2}-10^{-1})$ depending on the phase transition strength. These phase transitions can produce stochastic gravitational wave background to be probed by pulsar timing array experiments.

   hep-phastro-ph.COPRD(2023)·24 citations
10. 10*

    Chiral magnetohydrodynamics with zero total chirality

    Axel Brandenburg🇸🇪 · Kohei Kamada🇯🇵 · Kyohei Mukaida🇯🇵 · Kai Schmitz🇩🇪 · Jennifer Schober🇸🇪

    We study the evolution of magnetic fields coupled with chiral fermion asymmetry in the framework of chiral magnetohydrodynamics with zero initial total chirality. The initial magnetic field has a turbulent spectrum peaking at a certain characteristic scale and is fully helical with positive helicity. The initial chiral chemical potential is spatially uniform and negative. We consider two opposite cases where the ratio of the length scale of the chiral plasma instability (CPI) to the characteristic scale of the turbulence is smaller and larger than unity. These initial conditions might be realized in cosmological models such as certain types of axion inflation. The magnetic field and chiral chemical potential evolve with inverse cascading in such a way that the magnetic helicity and chirality cancel each other at all times. The CPI time scale is found to determine mainly the time when the magnetic helicity spectrum attains negative values at high wave numbers. The turnover time of the energy-carrying eddies, on the other hand, determines the time when the peak of the spectrum starts to shift to smaller wave numbers via an inverse cascade. The onset of helicity decay is determined by the time when the chiral magnetic effect becomes efficient at the peak of the initial magnetic energy spectrum. When spin flipping is important, the chiral chemical potential vanishes and the magnetic helicity becomes constant, which leads to a faster increase of the correlation length, as expected from magnetic helicity conservation. This also happens when the initial total chirality is imbalanced. Our findings have important implications for baryogenesis after axion inflation.

    hep-phastro-ph.COastro-ph.HEphysics.plasm-phPRD(2023)·16 citations
11. 11*

    Dimension-8 SMEFT Analysis of Minimal Scalar Field Extensions of the Standard Model

    John Ellis🇬🇧 · Ken Mimasu🇬🇧 · Francesca Zampedri🇬🇧

    We analyze the constraints obtainable from present data using the Standard Model Effective Field Theory (SMEFT) on extensions of the Standard Model with additional electroweak singlet or triplet scalar fields. We compare results obtained using only contributions that are linear in dimension-6 operator coefficients with those obtained including terms quadratic in these coefficients as well as contributions that are linear in dimension-8 operator coefficients. We also implement theoretical constraints arising from the stability of the electroweak vacuum and perturbative unitarity. Analyzing the models at the dimension-8 level constrains scalar couplings that are not bounded at the dimension-6 level. The strongest experimental constraints on the singlet model are provided by Higgs coupling measurements, whereas electroweak precision observables provide the strongest constraints on the triplet model. In the singlet model the present di-Higgs constraints already play a significant role. We find that the current constraints on model parameters are already competitive with those anticipated from future di- and tri-Higgs measurements. We compare our results with calculations in the full model, exhibiting the improvements when higher-order SMEFT terms are included. We also identify regions in parameter space where the SMEFT approximation appears to break down. We find that the combination of current constraints with the theoretical bounds still admits regions where the SMEFT approach is not valid, particularly for lower scalar boson masses.

    hep-phhep-exhep-thJHEP(2023)·46 citations
12. 12*

    Isolated photon production in association with a jet pair through next-to-next-to-leading order in QCD

    Simon Badger🇮🇹 · Michal Czakon🇩🇪 · Heribertus Bayu Hartanto🇬🇧 · Ryan Moodie🇮🇹 · Tiziano Peraro🇮🇹 · Rene Poncelet🇬🇧 · Simone Zoia🇮🇹

    In this work, we provide a comprehensive set of differential cross-section distributions for photon + di-jet production in proton-proton collisions with next-to-next-to-leading order precision in massless QCD. The event selection corresponds to recent measurements by the ATLAS collaboration. We observe an improved description of data in comparison to lower-order calculations in the case of observables that are expected to be well described by perturbation theory. The results also show better agreement with data than parton-shower-matched and multi-jet-merged predictions generated for the ATLAS analysis using the \textsc{Sherpa} Monte Carlo. A particular highlight of our study is the use of exact five-point two-loop virtual amplitudes. This is the first calculation of a complete two-to-three hadron-collider process at next-to-next-to-leading order in QCD that does not rely on the leading-colour approximation at two loops. We demonstrate, nevertheless, that the sub-leading-colour effects present in the infrared- and ultraviolet-finite double-virtual contributions are negligible in view of the remaining scale uncertainties.

    hep-phhep-exJHEP(2023)·72 citations
13. 13*

    Significance of classically forbidden regions for short baseline neutrino experiments

    Dharam Vir Ahluwalia🇮🇳

    Classically forbidden regions ($\mathtt{CFRs}$) are common to both non-relativistic quantum mechanics, and to relativistic quantum field theory. It is known since 2001 that $\mathtt{CFR}$ contributes roughly sixteen percent of energy to the ground state of a simple harmonic oscillator (Adunas G. Z. et al., Gen. Relativ. Gravit., 33 (2001) 183). Similarly, quantum field theoretic arguments yield a non-zero amplitude for a massive particle to cross the light cone (that is, into the $\mathtt{CFR}$). The signs of these amplitudes are opposite for fermions and antifermions. This has given rise to an erroneous conclusion that amplitude to cross the lightcone is identically zero. This is true as long as a measurement does not reveal the considered object to be a particle or antiparticle. However, neutrino oscillation experiments do measure a neutrino $\nu$, or an antineutrino $\bar{\nu }$. Here we show that in the context of neutrino oscillations these observations have the potential to resolve various short baseline anomalies for a sufficiently light lowest mass eigenstate. In addition, we make a concrete prediction for the upcoming results to be announced later this year by JSNS${}^2$.

    hep-phnucl-thquant-phEPL(2023)·0 citations
14. 14*

    The other variants of mixed $\mu$-$\tau$ symmetry

    Pralay Chakraborty🇮🇳 · Subhankar Roy🇮🇳

    Two new neutrino mass matrix textures exhibiting the \emph{mixed $\mu$-$\tau$ symmetry} are proposed. The mass matrices hint for a promising neutrino mixing schemes and find their connections with $\Delta (27)$ and $A_4$ discrete symmetry groups respectively.

    hep-phNPB(2023)·21 citations
15. 15*

    Does Quark Mixing play a role in the Lepton Sector?

    Francisco Albergaria🇵🇹 · G.C. Branco🇵🇹 · José Filipe Bastos🇵🇹 · J.I. Silva-Marcos🇵🇹

    We suggest a simple relation between the quark and the lepton mixing within the framework of type-I seesaw mechanism. We show that within our ansatz the empirical King-Mohapatra-Smirnov relation, which suggests a connection between the CKM and PMNS mixing where $|V_{13}^{\text{PMNS}}|\approx \frac{1}{\sqrt{2}}\sin ({\theta }_C)$, can be derived. This is possible within a restricted region of the Dirac and Majorana mass parameters.

    hep-phEPJC(2024)·2 citations
16. 16*

    The dark Stodolsky effect: constraining effective dark matter operators with spin-dependent interactions

    Guillaume Rostagni🇬🇧 · Jack D. Shergold🇬🇧

    We present a comprehensive discussion of the Stodolsky effect for dark matter (DM), and discuss two techniques to measure the effect and constrain the DM parameter space. The Stodolsky effect is the spin-dependent shift in the energy of a Standard Model (SM) fermion sitting in a bath of neutrinos. This effect, which scales linearly in the effective coupling, manifests as a small torque on the SM fermion spin and has historically been proposed as a method of detecting the cosmic neutrino background. We generalise this effect to DM, and give expressions for the induced energy shifts for DM candidates from spin-$0$ to spin-$\frac{3}{2}$, considering all effective operators up to mass dimension-6. In all cases, the effect scales inversely with the DM mass, but requires an asymmetric background. We show that a torsion balance experiment is sensitive to energy shifts of $\Delta E\gtrsim 10^{-28}\mathrm{eV}$, whilst a more intricate setup using a SQUID magnetometer is sensitive to shifts of $\Delta E\gtrsim 10^{-32}\mathrm{eV}$. Finally, we compute the energy shifts for a model of scalar DM, and demonstrate that the Stodolsky effect can be used to constrain regions of parameter space that are not presently excluded.

    hep-phhep-exJCAP(2023)·7 citations
17. 17*

    Weak decay constants of the neutral pseudoscalar mesons from lattice QCD+QED

    Z. R. Kordov🇦🇺 · R. Horsley🇬🇧 · W. Kamleh🇦🇺 · Y. Nakamura🇯🇵 · H. Perlt🇩🇪 · P. E. L. Rakow🇬🇧 · G. Schierholz🇩🇪 · H. Stüben🇩🇪 · R. D. Young🇦🇺 · J. M. Zanotti🇦🇺

    With increasing requirements for greater precision, it becomes essential to describe the effects of isospin breaking induced by both quark masses and electro-magnetic effects. In this work we perform a lattice analysis of the weak decay constants of the neutral pseudoscalar mesons including such isospin breaking effects, with particular consideration being given to the state mixing of the ${\pi }^0$, $\eta$ and ${\eta }^{\prime }$. We also detail extensions to the non-perturbative RI${}^{\prime }$-MOM renormalization scheme for application to non-degenerate flavour-neutral operators which are permitted to mix, and present initial results. Using flavour-breaking expansions in terms of quark masses and charges we determine the leptonic decay constants for the ${\pi }^0$ and $\eta$ mesons, demonstrating in principle how precision determinations of all neutral pseudoscalar decay constants could be reached in lattice QCD with QED and strong isospin-breaking accounted for.

    ↳ hep-lathep-ph2 citations
18. 18*

    A generalized hydrodynamizing initial stage for Heavy Ion Collisions

    Govert Nijs🇺🇸 · Wilke van der Schee🇨🇭

    We present an extended Bayesian analysis using Trajectum where the initial condition can now include binary scaling. For the far-from-equilibrium evolution before hydrodynamics we introduce an interpolation between free streaming and a holographically inspired evolution that exhibits fast hydrodynamization. We find strong evidence that binary scaling is incompatible with experimental data and find evidence that the holographic far-from-equilibrium evolution is preferred. We end with a discussion on several changes and improvements in the Bayesian framework.

    ↳ nucl-thhep-phnucl-ex30 citations
19. 19*

    Local Thermodynamics and Entropy for Relativistic Hydrostatic Equilibrium

    Shuichi Yokoyama🇯🇵

    By refining the method proposed in arXiv:2010.07660, entropy current and entropy density for a relativistic hydrostatic equilibrium system with spherical symmetry are constructed as a non-Noether conserved charge in the Einstein gravity with cosmological constant. It is shown that the constructed entropy density satisfies both the local Euler relation and the first law of thermodynamics non-perturbatively with respect to the Newton constant. Finally the established relativistic thermodynamics is applied to one of the systems with uniform energy density as a crude model of a degenerate star and its local thermodynamic observables are determined analytically.

    ↳ gr-qchep-phhep-thPLB(2024)·6 citations
20. 20*

    Exploring Mirror Twin Higgs Cosmology with Present and Future Weak Lensing Surveys

    Lei Zu🇨🇳 · Chi Zhang🇨🇳 · Hou-Zun Chen🇨🇳 · Wei Wang🇨🇳 · Yue-Lin Sming Tsai🇨🇳 · Yuhsin Tsai🇺🇸 · Wentao Luo🇨🇳 · Yi-Zhong Fan🇨🇳

    We explore the potential of precision cosmological data to study non-minimal dark sectors by updating the cosmological constraint on the mirror twin Higgs model (MTH). The MTH model addresses the Higgs little hierarchy problem by introducing dark sector particles. In this work, we perform a Bayesian global analysis that includes the latest cosmic shear measurement from the DES three-year survey and the Planck CMB and BAO data. In the early Universe, the mirror baryon and mirror radiation behave as dark matter and dark radiation, and their presence modifies the Universe's expansion history. Additionally, the scattering between mirror baryon and photon generates the dark acoustic oscillation process, suppressing the matter power spectrum from the cosmic shear measurement. We demonstrate how current data constrain these corrections to the $\Lambda$CDM cosmology and find that for a viable solution to the little hierarchy problem, the proportion of MTH dark matter cannot exceed about $30\%$ of the total dark matter density, unless the temperature of twin photon is less than $30\%$ of that of the standard model photon. While the MTH model is presently not a superior solution to the observed $H_0$ tension compared to the $\Lambda$CDM+$\Delta N_{\mathrm{eff}}$ model, we demonstrate that it has the potential to alleviate both the $H_0$ and $S_8$ tensions, especially if the $S_8$ tension persists in the future and approaches the result reported by the Planck SZ (2013) analysis. In this case, the MTH model can relax the tensions while satisfying the DES power spectrum constraint up to $k\lesssim 10h{\mathrm{Mpc}}^{-1}$. If the MTH model is indeed accountable for the $S_8$ and $H_0$ tensions, we show that the future China Space Station Telescope (CSST) can determine the twin baryon abundance with a $10\%$ level precision.

    ↳ astro-ph.COastro-ph.HEhep-phhep-thJCAP(2023)·19 citations
21. 21*

    Early Structure Formation from Cosmic String Loops in Light of Early JWST Observations

    Hao Jiao🇨🇦 · Robert Brandenberger🇨🇦 · Alexandre Refregier (McGill and ETH Zurich)🇨🇭

    Cosmic strings, if they exist, source nonlinear and non-Gaussian perturbations all the way back to the time of equal matter and radiation (and earlier). Here, we compute the mass function of halos seeded by a scaling distribution of cosmic string loops, and we compare the results with the predictions of the standard Gaussian $\Lambda$CDM model. Assuming a simple linear relation between stellar mass and halo mass, we also compute the stellar mass function. The contribution of cosmic strings dominates at sufficiently high redshifts $z>z_c$ where $z_c$ depends on the mass of the halo and on the mass per unit length $\mu$ of the strings and is of the order $z_c\sim 12$ for $G\mu =10^{-8}$. We find that strings with this value of $G\mu$ can explain the preliminary JWST data on the high redshift stellar mass density. Based on an extreme value statistic, we find that the mass of the heaviest expected string-seeded galaxy for the current JWST sky coverage is compatible with the heaviest detected galaxy. Given the uncertainties in the interpretation of the JWST data, we discuss predictions for higher redshift observations.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2023)·49 citations
22. 22*

    Fine tuning of rainbow gravity functions and Klein-Gordon particles in cosmic string rainbow gravity spacetime

    Omar Mustafa🇹🇷

    We argue that, as long as relativistic quantum particles are in point, the variable $y=E/E_p$ of the rainbow functions pair $g_{{}_0}(y)$ and $g_{{}_1}(y)$ should be fine tuned into $y=|E|/E_p$, where $E_p$ is the Planck's energy scale. Otherwise, the rainbow functions will be only successful to describe the rainbow gravity effect on relativistic quantum particles and the anti-particles will be left unfortunate. Under such fine tuning, we consider Klein-Gordon (KG) particles in cosmic string rainbow gravity spacetime in a non-uniform magnetic field (i.e., $\mathbf{B}=\nabla \times \mathbf{A}=\frac{3}{2}{B}_{\circ }r\hat{z}$ ). Then we consider KG-particles in cosmic string rainbow gravity spacetime in a uniform magnetic field (i.e., $\mathbf{B}=\nabla \times \mathbf{A}=\frac{1}{2}{B}_{\circ }\hat{z}$ ). Whilst the former effectively yields KG-oscillators, the later effectively yields KG-Coulombic particles. We report on the effects of rainbow gravity on both KG-oscillators and Coulombic particles using four pairs of rainbow functions: (i) , g_{_{1}}\left( y\right) =\sqrt{1-\epsilon y^{2}% }, (ii) $g_{{}_0}\left(y\right)=1$, g_{_{1}}\left( y\right) =\sqrt{% 1-\epsilon y}, (iii) $g_{{}_0}\left(y\right)=g_{{}_1}\left(y\right)={\left(1-ϵy\right)}^{-1}$, and (iv) $g_{{}_0}\left(y\right)=\left(e^{ϵy}-1\right)/ϵy$, $g_{{}_1}\left(y\right)=1$, where $y=|E|/E_p$ and $ϵ$ is the rainbow parameter. It is interesting to report that, all KG particles' and anti-particles' energies are symmetric about $E=0$ value (a natural relativistic quantum mechanical tendency), and a phenomenon of energy states to fly away and disappear from the spectrum is observed for the rainbow functions pair (iii) at $\gamma =ϵm/E_p=1$.

    ↳ gr-qcastro-ph.HEhep-ph3 citations
23. 23*

    Addressing the self-interaction for ELDER dark matter from the 21-cm signal

    Rupa Basu🇮🇳 · Debasish Majumdar🇮🇳 · Ashadul Halder🇮🇳 · Shibaji Banerjee🇮🇳

    The self-interacting dark matter can affect various cosmological processes. Such interactions can be number conserving (\emph{e.g.} $2\to 2$) or number violating (\emph{e.g.} $3\to 2,4\to 2$ etc.). The latter processes where three (or more) dark matter particles undergo self-annihilation/scattering to produce less number of dark matter is termed as ``Cannibalism'' process. In this work, the self-interaction of dark matter and the strength of such interactions are investigated in the light of experimental results of the global 21-cm spectrum of neural hydrogen from the era of cosmic dawn. From the present work, it appears that $2\to 2$ process is much more dominant over the $3\to 2$ process. It is also found that such interactions affect the dark matter-baryon elastic scattering cross-section. The study also indicates the presence of multi component dark matter of different mass range in the Universe.

    ↳ astro-ph.COastro-ph.HEhep-phInt.J.Mod.Phys.A(2025)·0 citations
24. 24*

    Universal Gravitational Wave Signatures of Cosmological Solitons

    Kaloian D. Lozanov🇯🇵 · Misao Sasaki🇯🇵 · Volodymyr Takhistov🇯🇵

    Cosmological solitonic objects such as monopoles, cosmic strings, domain walls, oscillons and Q-balls often appear in theories of the early Universe. We demonstrate that such scenarios are generically accompanied by a novel production source of gravitational waves stemming from soliton isocurvature perturbations. The resulting induced universal gravitational waves (UGWs) reside at lower frequencies compared to gravitational waves typically associated with soliton formation. We show that UGWs from axion-like particle (ALP) oscillons, originating from ALP misalignment, extend the frequency range of produced gravitational waves by more than two orders of magnitude regardless of the ALP mass and decay constant and can be observable in upcoming gravitational wave experiments. UGWs open a new route for gravitational wave signatures in broad classes of cosmological theories.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2025)·42 citations
25. 25*

    THESAN-HR: Galaxies in the Epoch of Reionization in warm dark matter, fuzzy dark matter and interacting dark matter

    Xuejian Shen🇺🇸 · Josh Borrow🇺🇸 · Mark Vogelsberger🇺🇸 · Enrico Garaldi🇩🇪 · Aaron Smith🇺🇸 · Rahul Kannan🇨🇦 · Sandro Tacchella🇬🇧 · Jesús Zavala🇮🇸 · Lars Hernquist🇺🇸 · Jessica Y.-C. Yeh🇺🇸 · Chunyuan Zheng🇺🇸

    Using high-resolution cosmological radiation-hydrodynamic (RHD) simulations (THESAN-HR), we explore the impact of alternative dark matter (altDM) models on galaxies during the Epoch of Reionization. The simulations adopt the IllustrisTNG galaxy formation model. We focus on altDM models that exhibit small-scale suppression of the matter power spectrum, namely warm dark matter (WDM), fuzzy dark matter (FDM), and interacting dark matter (IDM) with strong dark acoustic oscillations (sDAO). In altDM scenarios, both the halo mass functions and the UV luminosity functions at $z\gtrsim 6$ are suppressed at the low-mass/faint end, leading to delayed global star formation and reionization histories. However, strong non-linear effects enable altDM models to "catch up" with cold dark matter (CDM) in terms of star formation and reionization. The specific star formation rates are enhanced in halos below the half-power mass in altDM models. This enhancement coincides with increased gas abundance, reduced gas depletion times, more compact galaxy sizes, and steeper metallicity gradients at the outskirts of the galaxies. These changes in galaxy properties can help disentangle altDM signatures from a range of astrophysical uncertainties. Meanwhile, it is the first time that altDM models have been studied in RHD simulations of galaxy formation. We uncover significant systematic uncertainties in reionization assumptions on the faint-end luminosity function. This underscores the necessity of accurately modeling the small-scale morphology of reionization in making predictions for the low-mass galaxy population. Upcoming James Webb Space Telescope (JWST) imaging surveys of deep, lensed fields hold potential for uncovering the faint, low-mass galaxy population, which could provide constraints on altDM models.

    ↳ astro-ph.GAastro-ph.COhep-ph7 citations
26. 26*

    Anomalous Dimensions in Hypercubic Theories

    Alexander Bednyakov🇷🇺 · Johan Henriksson🇮🇹 · Stefanos R. Kousvos🇮🇹

    We perform a comprehensive perturbative study of the operator spectrum in multi-scalar theories with hypercubic global symmetry. This includes working out symmetry representations and their corresponding tensor structures. These structures are then used to compute the anomalous dimensions of scalar operators with up to four fields and arbitrary representations to six-loop order. Moreover, we determine one-loop anomalous dimensions for a large number of low-lying operators in the spectrum which include more powers of the fundamental field and/or insertions of derivatives. As an aside we show how projectors used in the conformal bootstrap can be conveniently reused in computations of anomalous dimensions. The results of our study are of use to the conformal bootstrap. They also illuminate features of conformal perturbation theory and the large $n$ expansion. Our results may be of interest for various crossover phenomena in statistical field theory. In total, we compute the scaling dimension of more than 300 operators, of which 16 are computed to six-loops. Our analysis is exhaustive with respect to group theory up to rank 4 for any number of flavours $n$, and also exhaustive with respect to which representations exist for $n\le 4$.

    ↳ hep-thcond-mat.stat-mechhep-phJHEP(2023)·8 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.