Tue·Oct 8, 2024Tuesday·October 8, 2024

1. 01*

   General mass variable flavor number scheme for $Z$ boson production in association with a heavy quark at hadron colliders

   Marco Guzzi🇺🇸 · Pavel Nadolsky🇺🇸 · Laura Reina🇺🇸 · Doreen Wackeroth🇺🇸 · Keping Xie🇺🇸

   We present a methodology to streamline implementation of massive-quark radiative contributions in calculations with a variable number of active partons in proton-proton collisions. The methodology introduces \textit{subtraction} and \textit{residual} heavy-quark parton distribution functions (PDFs) to implement calculations in the Aivazis-Collins-Olness-Tung (ACOT) factorization scheme and its simplified realization in various processes up to the next-to-the-next-to-leading order in the QCD coupling strength. Interpolation tables for bottom-quark subtraction and residual distributions for CT18 NLO and NNLO PDF ensembles are provided in the common LHAPDF6 format. A numerical calculation of $Z$-boson production with at least one $b$ jet at the Large Hadron Collider beyond the lowest order in QCD is considered for illustration purposes.

   hep-phPRD(2024)·11 citations
2. 02*

   Gravitational Particle Production of Scalars: Analytic and Numerical Approaches Including Early Reheating

   Leah Jenks🇺🇸 · Edward W. Kolb🇺🇸 · Keyer Thyme🇺🇸

   Cosmological gravitational particle production (GPP) is a generic mechanism by which particles are produced during the inflationary epoch. In this work we consider the GPP of massive scalars in an effort to fully understand the spectrum of the produced particles. We consider scalars which are conformally or minimally coupled to gravity, as well as models of both early and late reheating. We numerically calculate the particle production in each scenario and compare the results to analytic approximations from boundary matching, Stokes phenomenon, steepest descent, and inflaton scattering methods. For each method, we describe the regime of validity and show that there is good agreement between the analytic and numerical results.

   hep-phastro-ph.COgr-qchep-thJHEP(2025)·24 citations
3. 03*

   Impressions of Parton Distribution Functions

   Yang Yu🇨🇳 · Craig D. Roberts🇨🇳

   Parton distribution functions (DFs) have long been recognised as key measures of hadron structure. Today, theoretical prediction of such DFs is becoming possible using diverse methods for continuum and lattice analyses of strong interaction (QCD) matrix elements. Recent developments include a demonstration that continuum and lattice analyses yield mutually consistent results for all pion DFs, with behaviour on the far valence domain of light-front momentum fraction that matches QCD expectations. Theory is also delivering an understanding of the distributions of proton mass and spin amongst its constituents, which varies, of course, with the resolving scale of the measuring probe. Aspects of the pion DF and proton spin developments are sketched herein, along with some novel perspectives on gluon and quark orbital angular momentum.

   hep-phhep-exhep-latnucl-ex+1Chin.Phys.Lett.(2024)·21 citations
4. 04*

   Explaining the $B_{d(s)}\to K^{(\ast )}{\bar{K}}^{(\ast )}$ puzzle via chiral-flip in $R$-parity violating MSSM with seesaw mechanism

   Min-Di Zheng🇨🇳 · Qi-Liang Wang🇨🇳 · Li-Fen Lai🇨🇳 · Hong-Hao Zhang🇨🇳

   We study the non-leptonic puzzle of $B_{d(s)}\to K^{(\ast )}{\bar{K}}^{(\ast )}$ decay in the $R$-parity violating minimal supersymmetric standard model (RPV-MSSM) extended with the inverse seesaw mechanism. In this model, the chiral flip of sneutrinos can contribute to the observables $L_{K\bar{K}}$ and $L_{K^{\ast }{\bar{K}}^{\ast }}$, that is benefit for explaining the relevant puzzle. We also find that this unique effect can engage in the $B_s$-${\bar{B}}_s$ mixing. We utilize the scenario of complex ${\lambda }^{\prime }$ couplings to fulfill the recent stringent constraint of $B_s$-${\bar{B}}_s$ mixing, and examine other related bounds of $B,K$-meson decays, lepton decays, neutrino data, $Z$ decays, oblique parameters, CP violations (CPV), etc. Besides, inspired by the new measurement of $\mathcal{B}(B^{+}\to K^{+}\nu \bar{\nu })$ by Belle II, which shows about $2.7\sigma$ higher than the Standard Model (SM) prediction, we also investigate the New Physics (NP) enhancement to this observable.

   hep-phPRD(2025)·6 citations
5. 05*

   The Revival of $U(1{)}_{L_e-L_{\mu }}$: A Natural Solution for $(g-2{)}_{\mu }$ with a Sub-GeV Dark Matter

   Bibhabasu De🇮🇳

   The experiments searching for a hidden gauge sector with a leptophilic neutral gauge boson have already ruled out $U(1{)}_{L_e-L_{\mu }}$ as a feasible extension of the Standard Model (SM) gauge group (${\mathcal{G}}_{\mathrm{SM}}$) for explaining the observed discrepancy in $(g-2{)}_{\mu }$. The paper proposes a simple extension of the minimal particle content of ${\mathcal{G}}_{\mathrm{SM}}\otimes U(1{)}_{L_e-L_{\mu }}$ with a TeV-scale scalar leptoquark $S_1$. Due to the non-trivial transformation of $S_1$ under $U(1{)}_{L_e-L_{\mu }}$, the model generates additional one-loop contributions to $(g-2{)}_{\mu }$, reviving the considered gauge extension within the experimentally allowed regions of the parameter space. The model can also accommodate a viable Dark Matter (DM) candidate $\chi$ -- a vector-like SM-singlet fermion in the sub-GeV mass regime. The theory provides a natural framework to test the proposed DM phenomenology through electron excitation signals. Moreover, the DM-specific observables and $(g-2{)}_{\mu }$ being connected through the New Physics (NP) parameters, the future beam dump experiments hunting for light, feebly interacting particles and the DM direct detection experiments are complementary to each other for constraining/falsifying the model.

   hep-phEPJC(2025)·6 citations
6. 06*

   Enhancing Electroweak Baryogenesis: The Role of Dimension-Six Operators in the Real Singlet Extension of the Standard Model

   Apostolos Giovanakis🇬🇷

   This study investigates the electroweak baryogenesis (EWBG) in the real singlet extension of the Standard Model (SM), including dimension-six operators, which couple the Higgs boson to a real singlet scalar field. We show that the electroweak phase transition is a one-step or a two-step phase transition, depending on the parameters of the singlet extension. In the majority of the parameter space, the electroweak phase transition proceeds as a two-step phase transition: an initial phase transition in the singlet sector at high temperatures, followed by a first-order phase transition in the Higgs sector. Interestingly, including the dimension-six operator, the electroweak phase transition occurs in regions of the parameter space, which were ruled out in the singlet extensions of the SM without the dimension-six operator. This is more evident for low singlet masses, which are excluded by the experimental constraints from the invisible decays of the Higgs boson. In addition, the real singlet extension explains the observed baryon asymmetry of the Universe introducing an additional source of \(CP\) violation in the SM via a second dimension-six operator, which contributes to the top-quark mass. These results provide new pathways for EWBG, expanding the viable parameter space for future collider and gravitational wave experiments, especially for low singlet masses.

   hep-phPhys.Dark Univ.(2024)·5 citations
7. 07*

   Do Finite Density Effects Jeopardize Axion Nucleophobia in Supernovae?

   Luca Di Luzio🇮🇹 · Vincenzo Fiorentino🇮🇹 · Maurizio Giannotti🇪🇸 · Federico Mescia🇮🇹 · Enrico Nardi🇮🇹

   Nucleophobic axion models, wherein axion couplings to both protons and neutrons are simultaneously suppressed, can relax the stringent constraints from SN 1987A. However, it remains uncertain whether these models maintain their nucleophobic property under the influence of finite baryon density effects. These are especially relevant in astrophysical environments near saturation density, such as Supernovae (SNe). In this study, we demonstrate that the nucleophobic solution remains viable also at finite density. Furthermore, we show that the SN axion bound relaxes significantly in nucleophobic models, even when accounting for the integration over the non-homogeneous environment of the SN core.

   hep-phastro-ph.HEPRD(2025)·11 citations
8. 08*

   On the Effects of Elementary and Bound State Fields on Vacuum Stability in $t\bar{t}$ Production at the LHC

   Yoshiki Matsuoka🇯🇵

   The recent report by the CMS Collaboration on the excess of top and anti-top pair production is examined with regard to the improvement of vacuum stability under two simple scenarios: one with the existence of toponium $({\eta }_t)$, and the other with an additional elementary field $(\Psi )$. In both cases, the values of each coupling constant are restricted by the Multicritical Point Principle (MPP). Two scenarios are considered. The first incorporates the effect of toponium $({\eta }_t)$, inspired by the Bardeen-Hill-Lindner (BHL) framework, and the second embeds $\Psi$ into the Standard Model (SM) as a minimal model close to an inert doublet model. From these analyses, it is found that toponium cannot satisfy the MPP, whereas the additional elementary field can.

   hep-phPLB(2026)·3 citations
9. 09*

   Hadronic Weak Decays of Charmed Baryons in the Topological Diagrammatic Approach: An Update

   Hai-Yang Cheng🇹🇼 · Fanrong Xu🇨🇳 · Huiling Zhong🇨🇳

   There exist two distinct ways in realizing the approximate SU(3) flavor symmetry of QCD to describe the two-body nonleptonic decays of charmed baryons: the irreducible SU(3) approach (IRA) and the topological diagram approach (TDA). The TDA has the advantage that it is more intuitive, graphic and easier to implement model calculations. We perform a global fit to the currently available data of two-body charmed baryon decays within the framework of the TDA and IRA. The number of the minimum set of tensor invariants in the IRA and the topological amplitudes in the TDA is the same, namely, five in the tree-induced amplitudes and four in the penguin amplitudes. Since we employ the new LHCb measurements to fix the sign ambiguity of the decay parameters $\beta$ and $\gamma$, the fit results for the magnitudes of $S$- and $P$-wave amplitudes and their phase shift ${\delta }_P-{\delta }_S$ in both the TDA and IRA are more trustworthy than our previous analyses with uncertainties substantially improved. These results can be tested in the near future. The perspective of having direct {\it CP} violation in the charmed baryon sector at the per mille level is briefly discussed.

   hep-phhep-exPRD(2025)·12 citations
10. 10*

    Leptogenesis from magnetic helicity of gauged $\text{U}(1{)}_{B-L}$

    Hajime Fukuda🇯🇵 · Kohei Kamada🇨🇳 · Thanaporn Sichanugrist🇯🇵

    If the $B-L$ symmetry is gauged with the addition of right-handed neutrinos, the standard model $B-L$ current is anomalous with respect to the $B-L$ gauge field itself. Then, the anomaly relation implies that the magnetic helicity of the $B-L$ gauge field is related to the standard model $B-L$ charges, although the whole universe is $B-L$ neutral with right-handed neutrinos. Based on this, we propose a new leptogenesis scenario with the gauged $B-L$ symmetry as follows. First, the magnetic helicity of the $B-L$ gauge field is generated, e.g., by the axion inflation, together with the standard model and right-handed neutrino $B-L$ charges, with the net $B-L$ charge kept zero. The $B-L$ charges in the standard model and right-handed neutrino sectors are then subject to washout effects from the interactions between them. After the washout effects decouple, the $B-L$ gauge symmetry is Higgsed and the magnetic helicity of the $B-L$ gauge field decays and generates $B-L$ charges in the both sector; thanks to the washout effects, we obtain a non-zero $B-L$ asymmetry. We show that the baryon asymmetry of the universe can be generated in this scenario, discussing the decay of the magnetic helicity of the $B-L$ gauge field and the interactions between the right-handed neutrinos and the standard model particles.

    hep-phastro-ph.COJHEP(2025)·4 citations
11. 11*

    Dark matter interpretation of GRB 221009A: a singlet scalar explains LHAASO data

    S. Peyman Zakeri🇮🇷

    In this work, we find a new signal of dark matter (DM) through an intensive gamma ray burst (GRB), called GRB 221009A. This indirect detection approach devotes to the decay of DM particles into high energy (HE) photons. In this context, a singlet scalar DM generated at the redshift of the GRB is up-scattered by the high energy cosmic rays (HECRs) during its propagation to Earth. This highly boosted DM then possesses a high flux and undergoes a dominant di-photon decay before reaching the detector. The Large High Altitude Air Shower Observatory (LHAASO) probes such energetic gamma rays whereby has recorded a 18 TeV event for the aforementioned GRB.

    hep-phastro-ph.HE0 citations
12. 12*

    String tension and Polyakov loop in a rotating background

    Jun-Xia Chen🇨🇳 · Sheng Wang🇨🇳 · De-Fu Hou🇨🇳 · Hai-Cang Ren🇨🇳

    We study the influence of a rotation on the string tension and the temperature of the confinement-deconfinement transition of gluodynamics by gauge/gravity duality. We explore two distinct approaches, global transformation and local transformation, to introduce rotation and compare the results. It is shown that the string tension extracted from the free energy in the presence of a heavy quarkonium decreases with the increasing angular velocity, while the transition temperature determined by the Polyakov loop increases with increasing angular velocity, which is in line with lattice simulations.

    hep-phPRD(2025)·13 citations
13. 13*

    New collider implications on a strongly first order EWPT

    Ricardo R. Florentino🇯🇵 · Shinya Kanemura🇯🇵 · Masanori Tanaka🇨🇳

    In order to understand the early history of the universe, and to test baryogenesis models, determining the nature of the electroweak phase transition is imperative. The order and strength of this transition is strongly correlated to relatively large deviations in the $hhh$ coupling. In models where a considerable part of the $hhh$ coupling deviation is caused by charged particle loops, the $h\gamma \gamma$ coupling is also expected to deviate considerably. In this talk, by using a model-independent approach, I explain how to obtain conditions that are sufficient for a strongly first order phase transition. After the $h\gamma \gamma$ coupling is determined with precision at the HL-LHC, these conditions can be tested at Future Linear Colliders by measurements of the $hhh$ coupling, to conclusively determine the nature of the electroweak phase transition and the viability of electroweak baryogenesis on models with new charged scalars.

    hep-phastro-ph.COEPJ Web Conf.(2024)·1 citation
14. 14*

    The asymptotic behavior of Lorentz-violating photon fields

    Zhi Xiao🇨🇳 · Hao Wang🇨🇳

    In this work, we derive the Newman-Penrose formalism of Maxwell's equations using two approaches: differential forms and intrinsic derivatives. Denoting $(k_{AF}{)}^{\mu }$ as $k^{\mu }$, with $k^{\mu }=(k^t,k^r,0,0)$ in spherically symmetric spacetimes, we show that the expansion in $r^{-1}$ fails to produce consistent, closed solutions due to the inability to separate Lorentz-violating (LV) phase factors, as the Lorentz-invariant (LI) null tetrad does not adapt to the LV wavefront. Moreover, with exact formal solutions, we demonstrate that the expansion is nonperturbative in the LV parameter $k^2\equiv k^t-k^r$. For $r\gg 1/k^2$, higher powers of $k^2$ dominate over lower powers, as the latter decay more rapidly with increasing $r$. Although the Coulomb mode ${\varphi }_1\sim \mathcal{O}(\ln r/r^2)$ deviates from the LI expectation $\mathcal{O}(r^{-2})$ due to LV corrections, the leading outgoing radiation mode remains unaffected, i.e., ${\varphi }_2\sim \mathcal{O}(r^{-1})$. Given the constraint $|k_{AF}|\le 10^{-44}$GeV \cite{CMBLV-N}, the three complex scalars ${\varphi }_a$ ($a=0,1,2$) still obey the peeling theorem: ${\varphi }_a\sim \mathcal{O}(r^{(a-3)}),a=0,1,2$ for large, finite distances.

    hep-phgr-qcPRD(2025)·5 citations
15. 15*

    Hartree-Fock all-heavy $c$, $b$ multiquarks and constraints on new top-sector physics

    Alejandro Alonso-Valero🇪🇸 · Daniel Berzal-Rozalén🇪🇸 · Felipe J. Llanes-Estrada🇪🇸 · Mario Camilo Pardo🇪🇸 · Clara Peset🇪🇸

    We deploy the Hartree-Fock approximation for all-heavy quark hadrons, including quarkonium, baryons, tetraquarks, pentaquarks, dibaryons and up to the 12-body dibaryon-antidibaryon which completely fill the $1s$ orbital, in a unified manner, with the spinless LO Coulomb interaction and beyond. After treating the $c$ and $b$ quarks in various combinations, we delve a bit longer on $t$-quark bound states. We extend the negative result of Kuchiev, Flambaum and Shuryak on the 12-body topball to now include the NLO QCD potential. We find that none of the examined multitop states should have binding energy exceeding their width in the Standard Model. Additional new-physics interactions can then be constrained by experimental searches for these bound states, assuming they are not detected, at a level somewhat less stringent than standing HEFT bounds, but with different systematics.

    hep-phJHEP(2025)·5 citations
16. 16*

    Unraveling the Energy-Energy Correlators for Heavy Flavor Tagged Jets in pp, p+Pb and Pb+Pb Collisions

    Ke-Ming Shen🇨🇳 · Shi-Yong Chen🇨🇳 · Yu-Jie Huang🇨🇳 · Wei Dai🇨🇳 · Ben-Wei Zhang🇨🇳

    In this study, energy-energy correlator (EEC) distributions for the ${\mathrm{D}}^0$, ${\mathrm{B}}^0$-tagged, inclusive, and the PYTHIA generated pure quark jets are computed in pp, p+Pb, and Pb+Pb collisions at \sqrts =5.02 TeV for a same jet transverse momentum interval 15-30 GeV. We find the number of particles per jet determines the height of the EEC distribution in pp baseline. The averaged energy weight distribution resulted in a shift of the originally larger angular distributed particle distribution to a smaller RL, thereby obtaining an EEC distribution. The EEC distributions for all quark-tagged jets in A+A exhibit a noticeable shift towards larger RL region, suggesting that the jets will be more widely distributed compared to those in pp collisions. The jet quenching effect will cause the pair angular distribution to shift towards larger values and increase the number of particles per jet. This redistribution of energy within the jets suggests that the already reduced jet energy is redistributed among a larger number of particles, leading to a reduced energy weight per pair. The enhancement of the number of particles per jet and the reduced averaged energy weight interplay with each other to form the medium modification of EEC.

    hep-phnucl-th3 citations
17. 17*

    Analyzing the $D^{\ast }{D}^{\ast }{D}^{\ast }$ system: Hexaquark states and the Efimov effect

    Pablo G. Ortega🇪🇸

    In this work we investigate the possible emergence of Efimov states in the $D^{\ast }{D}^{\ast }{D}^{\ast }$ system with $J^P=0^{-}$ and isospin $I=\frac{1}{2}$, assuming the existence of the heavy partner of the $T_{cc}^{+}$, dubbed $T_{cc}^{\ast }$, near the $D^{\ast }{D}^{\ast }$ threshold as predicted by Heavy-Quark Spin Symmetry. We find that $(I)J^P=(\frac{1}{2})0^{-}$ three-body bound states can be formed, with properties that suggest that the Efimov effect can be realised for reasonable values of the molecular probability and binding energy of the $T_{cc}^{\ast }$.

    hep-phPoS(2025)·0 citations
18. 18*

    Quark correlation functions at three-loop order and extraction of splitting functions

    Chen Cheng🇨🇳 · Li-Hong Huang🇨🇳 · Xiang Li🇨🇳 · Zheng-Yang Li🇺🇸 · Yan-Qing Ma🇨🇳

    We present the first complete next-to-next-to-next-to-leading-order calculation of the matching coefficients that link unpolarized flavor non-singlet parton distribution functions with lattice QCD computable correlation functions. By using this high-order result, we notice a reduction in theoretical uncertainties compared to relying solely on previously known lower-order matching coefficients. Furthermore, based on this result we have extracted the three-loop unpolarized flavor non-singlet splitting function, which is in agreement with the state-of-the-art result. Due to the simplicity of our method, it has the potential to advance the calculation of splitting functions to the desired four-loop order.

    hep-phhep-latPRL(2025)·5 citations
19. 19*

    How charming can the Higgs be?

    Artemis Sofia Giannakopoulou🇺🇸 · Patrick Meade🇺🇸 · Mauro Valli🇮🇹

    The coupling of the Higgs boson to first and second generation fermions has yet to be measured experimentally. There still could be very large deviations in these couplings, as the origin of flavor is completely unknown. Nevertheless, if Yukawa couplings are modified, especially for light generations, there are generically strong constraints from flavor-changing neutral currents (FCNCs). Therefore, it is imperative to understand whether there exists viable UV physics consistent with current data that motivates future Higgs coupling probes. In particular, the charm-quark Yukawa is the next quark coupling that could be measured at the LHC if it is a few times larger than the SM and compatible with flavor data. This is difficult to achieve in the context of standard ansatz such as Minimal Flavor Violation. In this paper we show that within the framework of Spontaneous Flavor Violation (SFV), using a Two Higgs Doublet Model as an example, the Higgs can be sufficiently charming that new LHC probes are relevant. In this charming region, we show that new Higgs states near the EW scale with large couplings to quarks are required, providing complementary observables or new constraints on the SM Yukawa couplings. The down-type SFV mechanism enabling the suppression of FCNCs also allows for independent modifications to the up-quark Yukawa coupling, which we explore in detail as well.

    hep-phhep-exJHEP(2025)·7 citations
20. 20*

    Neutrino Oscillations in Presence of Diagonal Elements of Scalar NSI: An Analytic Approach

    Dharitree Bezboruah🇮🇳 · Dibya S. Chattopadhyay🇮🇳 · Abinash Medhi🇮🇳 · Arnab Sarker🇮🇳 · Moon Moon Devi🇮🇳

    Scalar Non-Standard Interactions (SNSI) in neutrinos can arise when a scalar mediator couples to both neutrinos and standard model fermions. This beyond the Standard Model (BSM) scenario is particularly interesting as the SNSI contribution appears as a density-dependent perturbation to the neutrino mass, rather than appearing as a matter-induced potential, and the neutrino oscillation probabilities uniquely depend on the absolute neutrino masses. In this work, we show the complex dependence of the SNSI contributions on the neutrino masses and discuss how the mass of the lightest neutrino would regulate any possible SNSI contribution in both mass ordering scenarios. We derive the analytic expressions for neutrino oscillation probabilities, employing the Cayley-Hamilton theorem, in the presence of diagonal elements of SNSI. The expressions are compact and shows explicit dependence on matter effects and the absolute neutrino masses. The analytic expressions calculated here allow us to obtain the dependence of the SNSI contribution on mass terms of the form $m_1+m_2$, $m_2-m_1$, $m_1{c}_{12}^2+m_2{s}_{12}^2,$ $m_1{s}_{12}^2+m_2{c}_{12}^2$, and $m_3$. We then explore the non-trivial impact of neutrino mass ordering on the SNSI contribution. The dependence of the SNSI contribution on the 3$\nu$ parameters is then thoroughly explored using our analytic expressions.

    hep-phJHEP(2025)·7 citations
21. 21*

    The Monte Carlo replica method: investigating the effects of non-linearity

    Mark N. Costantini🇬🇧

    This paper presents an in-depth mathematical analysis of the Monte Carlo replica method, commonly used in global fitting studies within the high-energy physics theory field. For the first time, we offer a rigorous derivation of the parameter distributions resulting from this method, demonstrating that, while they align with Bayesian posteriors in linear models, they deviate in non-linear cases. We then numerically assess this discrepancy in a phenomenologically important context: fitting SMEFT Wilson coefficients. Our findings reveal that when non-linearity plays a significant role, the uncertainty estimates for key quantities differ between the two approaches.

    hep-phPoS(2025)·0 citations
22. 22*

    SPECTER: Efficient Evaluation of the Spectral EMD

    Rikab Gambhir🇺🇸 · Andrew J. Larkoski🇺🇸 · Jesse Thaler🇺🇸

    The Energy Mover's Distance (EMD) has seen use in collider physics as a metric between events and as a geometric method of defining infrared and collinear safe observables. Recently, the Spectral Energy Mover's Distance (SEMD) has been proposed as a more analytically tractable alternative to the EMD. In this work, we obtain a closed-form expression for the Riemannian-like p = 2 SEMD metric between events, eliminating the need to numerically solve an optimal transport problem. Additionally, we show how the SEMD can be used to define event and jet shape observables by minimizing the distance between events and parameterized energy flows (similar to the EMD), and we obtain closed-form expressions for several of these observables. We also present the SPECTER framework, an efficient and highly parallelized implementation of the SEMD metric and SEMD-derived shape observables as an analogue of the previously-introduced SHAPER for EMD-based computations. We demonstrate that computing the SEMD with SPECTER can be up to a thousand times faster than computing the EMD with standard optimal transport libraries.

    hep-phhep-exhep-thJHEP(2025)·14 citations
23. 23*

    NuFit-6.0: Updated global analysis of three-flavor neutrino oscillations

    Ivan Esteban🇪🇸 · M.C. Gonzalez-Garcia🇪🇸 · Michele Maltoni🇪🇸 · Ivan Martinez-Soler🇬🇧 · João Paulo Pinheiro🇪🇸 · Thomas Schwetz🇩🇪

    We present an updated global analysis of neutrino oscillation data as of September 2024. The parameters ${\theta }_{12}$, ${\theta }_{13}$, $\Delta m_{21}^2$, and $|\Delta m_{3\ell }^2|$ ($\ell =1,2$) are well-determined with relative precision at $3\sigma$ of about 13\%, 8\%, 15\%, and 6\%, respectively. The third mixing angle ${\theta }_{23}$ still suffers from the octant ambiguity, with no clear indication of whether it is larger or smaller than $45^{\circ }$. The determination of the leptonic CP phase ${\delta }_{CP}$ depends on the neutrino mass ordering: for normal ordering the global fit is consistent with CP conservation within $1\sigma$, whereas for inverted ordering CP-violating values of ${\delta }_{CP}$ around $270^{\circ }$ are favored against CP conservation at more than $3.6\sigma$. While the present data has in principle $2.5$--$3\sigma$ sensitivity to the neutrino mass ordering, there are different tendencies in the global data that reduce the discrimination power: T2K and NOvA appearance data individually favor normal ordering, but they are more consistent with each other for inverted ordering. Conversely, the joint determination of $|\Delta m_{3\ell }^2|$ from global disappearance data prefers normal ordering. Altogether, the global fit including long-baseline, reactor and IceCube atmospheric data results into an almost equally good fit for both orderings. Only when the ${\chi }^2$ table for atmospheric neutrino data from Super-Kamiokande is added to our ${\chi }^2$, the global fit prefers normal ordering with $\Delta {\chi }^2=6.1$. We provide also updated ranges and correlations for the effective parameters sensitive to the absolute neutrino mass from $\beta$-decay, neutrinoless double-beta decay, and cosmology.

    hep-phhep-exJHEP(2024)·743 citations
24. 24*

    Astrophysical and Cosmological Probes of Boosted Dark Matter

    Jeong Han Kim🇰🇷 · Kyoungchul Kong🇺🇸 · Se Hwan Lim🇰🇷 · Jong-Chul Park🇰🇷

    We present an in-depth study of two-component cold dark matter via extensive N-body simulations. We examine various cosmological observables including the temperature evolution, power spectrum, density perturbation, maximum circular velocity functions, and galactic density profiles. We find that a significant mass difference between the two components, coupled with the annihilation of the heavier into the lighter component, imparts warm dark matter (WDM)-like characteristics to the latter. This model benefits from the unique features of WDM, such as modifications to the matter power spectrum and density profiles, while avoiding stringent observational constraints on WDM mass. The two-component dark-matter model aligns with observational data and suggests new avenues for dark-matter detection in terrestrial experiments, particularly for light, sub-MeV DM candidates. Our findings provide a framework for understanding the small-scale structures and offer guidance for future particle physics and cosmological studies.

    hep-phastro-ph.COastro-ph.HEJCAP(2025)·12 citations
25. 25*

    Supersymmetric QCD on the lattice: Fine-tuning and counterterms for the Yukawa and quartic couplings

    M. Costa🇨🇾 · H. Herodotou🇨🇾 · H. Panagopoulos🇨🇾

    In this study, we determine the fine-tuning of parameters in $\mathcal{N}=1$ Supersymmetric QCD, discretized on a Euclidean lattice. Our focus is on the renormalization of Yukawa (gluino-quark-squark interactions) and quartic (four-squark interactions) couplings. Given that SUSY is broken on the lattice, non-supersymmetric counterterms must be added to the discretized Lagrangian, with coefficients which must be appropriately fine-tuned in order to recover SUSY in the continuum limit. To deduce the renormalization factors and the coefficients of the counterterms, we compute the relevant three-point (for the Yukawa couplings) and four-point Green's functions (for the quartic couplings) perturbatively to one-loop and to the lowest order in lattice spacing. Both dimensional and lattice regularizations are used to implement the Modified Minimal Subtraction scheme. Our lattice formulation employs the Wilson discretization for gluino and quark fields, the Wilson gauge action for gluons, and naive discretization for squark fields. One main difficulty in this study lies in the fact that different components of squark fields mix among themselves at the quantum level. Consequently, for an appropriate fine-tuning of the couplings, these mixings must be taken into account in the renormalization conditions. All Green's functions and renormalization factors exhibit an explicit dependence on the number of colors, $N_c$, the number of flavors, $N_f$, and the gauge parameter, $\alpha$, which are left unspecified. This work follows previous investigations on SQCD and finalizes the one-loop fine-tuning of the SQCD action on the lattice, paving the way for numerical simulations of SQCD.

    ↳ hep-lathep-phPoS(2025)·1 citation
26. 26*

    Kubo formula for spin hydrodynamics: spin chemical potential as leading order in gradient expansion

    Sourav Dey🇮🇳 · Arpan Das🇮🇳

    We present a first-order dissipative spin hydrodynamic framework, where the spin chemical potential ${\omega }^{\mu \nu }$ is treated as the leading term in the hydrodynamic gradient expansion, i.e., ${\omega }^{\mu \nu }\sim \mathcal{O}(1)$. We argue that for the consistency of the theoretical framework, the energy-momentum tensor needs to be symmetric at least up to order $\mathcal{O}(\partial )$. We consider the phenomenological form of the spin tensor, where it is anti-symmetric in the last two indices only. A comprehensive analysis of spin hydrodynamics is conducted using both macroscopic entropy current analysis and microscopic Kubo formalism, establishing consistency between the two approaches. A key finding is the entropy production resulting from spin-orbit coupling, which alters the traditional equivalence between the Landau and Eckart fluid frames. Additionally, we identify cross-diffusion effects, where vector dissipative currents are influenced by gradients of both spin chemical potential and chemical potential corresponding to the conserved charge through off-diagonal transport coefficients. Two distinct methods for decomposing the spin tensor are proposed, and their equivalence is demonstrated through Kubo relations.

    ↳ nucl-thhep-phhep-thPRD(2025)·21 citations
27. 27*

    Persistence of charmed hadrons in QGP from lattice QCD

    Sipaz Sharma🇩🇪

    We study the nature of charm degrees of freedom near the chiral crossover based on lattice QCD calculations of the second and fourth-order cumulants of charm fluctuations, and their correlations with net baryon number, electric charge, and strangeness fluctuations. We show that below the chiral crossover temperature, $T_{pc}$, the thermodynamics of charm can be very well understood in terms of charmed hadrons. We present evidence that above $T_{pc}$, however, charm quark-like excitations emerge as new degrees of freedom contributing to the partial charm pressure. Nonetheless, up to temperatures as high as 175 MeV, charmed hadron-like excitations significantly contribute to the partial charm pressure.

    ↳ hep-lathep-phnucl-thInt.J.Mod.Phys.A(2025)·4 citations
28. 28*

    Azimuthal Anisotropy Scaling for Identified Mesons and Baryons: Insights into Medium Transport Properties, Equation of State and Hadronic Re-scattering

    Roy A. Lacey (Department of Chemistry, Stony Brook University, Stony Brook, NY, USA)🇺🇸

    Scaling functions for the centrality and transverse momentum dependence of \(v_2(p_T,\text{cent})\) and \(v_3(p_T,\text{cent})\) are constructed for identified mesons and baryons in Pb+Pb (\(\sqrt{s_{NN}}=2.76,\ 5.02\)~TeV), Xe+Xe (5.44~TeV), and Au+Au (0.2~TeV) collisions. These species-resolved functions capture the interplay of initial geometry, viscous attenuation, radial flow, partonic energy loss, and hadronic re-scattering across both flow- and quenching-dominated regimes. The systematic growth of the radial-flow parameter \(\zeta_{\rm rf}\) with multiplicity and beam energy provides direct empirical constraints on the equation of state (EOS) of hot QCD matter. The extracted parameters also yield differential constraints on the specific shear viscosity \(\eta/s\), the jet-quenching parameter \(\hat{q}\), and late-stage hadronic dynamics. LHC systems exhibit low \(\eta/s\), strong radial flow, and negligible re-scattering at high energy density, whereas Au+Au at RHIC energy shows even lower \(\eta/s\), weaker radial flow, finite re-scattering, and reduced energy density. The coexistence of strong radial flow at low \(p_T\) and significant jet suppression at high \(p_T\) emerges as a defining hallmark of QGP formation, establishing the framework as a quantitative probe of QGP transport properties and EOS stiffness.

    ↳ nucl-exhep-exhep-phnucl-th2 citations
29. 29*

    From Landau two-fluid model to de Sitter Universe

    G.E. Volovik🇷🇺

    The condensed matter analogs are useful for consideration of the phenomena related to the quantum vacuum. This is because in condensed matter we know physics both in the infrared and in the ultraviolet limits, while in particle physics and gravity the physics at trans-Planckian scale is unknown. One of the corner stones of the connections between the non-relativistic condensed matter and the modern relativistic theories is the two-fluid hydrodynamics of superfluid helium. The dynamics and thermodynamics of the de Sitter state of the expansion of the Universe bear some features of the multi-fluid system. There are actually three components: the quantum vacuum, the gravitational component and relativistic matter. The expanding de Sitter vacuum serves as the thermal bath with local temperature, which is twice the Gibbons-Hawking temperature related to the cosmological horizon. This local temperature leads to the heating of matter component and the gravitational component. The latter behaves as Zel'dovich stiff matter and represents the dark matter. In equilibrium and in the absence of the conventional matter the positive partial pressure of dark matter compensates the negative partial pressure of quantum vacuum. That is why in the full equilibrium the total pressure is zero. This is similar to the superfluid and normal components in superfluids, which together produce the zero pressure of the liquid in the absence of environment. If one assumes that in dynamics, the gravitational dark matter behaves as the real Zel'dovich stiff matter, one obtains that both components experience the power law decay due to the energy exchange between these components. Then it follows that their values at present time have the correct order of magnitude. We also consider the other problems through the prism of condensed matter physics, including the black holes and Planck constant.

    ↳ gr-qccond-mat.otherhep-phPhys.Usp.(2025)·7 citations
30. 30*

    Phase Diagrams of Relativistic Selfinteracting Boson System

    V. Gnatovskyy🇺🇦 · D. Anchishkin🇺🇦 · D. Zhuravel🇺🇦 · V. Karpenko🇺🇦

    Within the Canonical Ensemble, we investigate a system of interacting relativistic bosons at finite temperatures and finite isospin densities in a mean-field approach. The mean field contains both attractive and repulsive terms. Temperature and isospin-density dependencies of thermodynamic quantities were obtained. It is shown that in the case of attraction between particles in a bosonic system, a liquid-gas phase transition develops against the background of the Bose-Einstein condensate. The corresponding phase diagrams are given. We explain the reasons why the presence of a Bose condensate significantly increases the critical temperature of the liquid-gas phase transition compared to that obtained for the same system within the framework of the Boltzmann statistics. Our results may have implications for the interpretation of experimental data, in particular, how sensitive the critical point of the mixed phase is to the presence of the Bose-Einstein condensate.

    ↳ nucl-thhep-phquant-phUkr.J.Phys.(2024)·1 citation
31. 31*

    Machine Learning Constraints on Dark Matter Annihilation during the Epoch of Reionization: A CNN Analysis of the 21-cm Signal

    Atsushi J. Nishizawa🇯🇵 · Pravin Kumar Natwariya🇨🇳 · Kenji Kadota🇨🇳

    We explore the impact of dark matter annihilation on the 21-cm signal during the cosmic dawn and epoch of reionization (EoR). Using modified 21cmFAST simulations and convolutional neural networks (CNNs), we investigate how energy injected into the intergalactic medium (IGM) through dark matter annihilation affects the evolution of the 21-cm differential brightness temperature. Focusing on two annihilation channels, photon-photon ($\gamma \gamma$) and electron-positron ($e^{+}{e}^{-}$), we examine a broad range of dark matter masses and annihilation cross-sections. Our results show that CNNs outperform traditional power spectrum analysis by effectively distinguishing between subtle differences in simulated 21-cm maps produced by annihilation and non-annihilation scenarios. We also demonstrate that the structure formation boost, driven by dark matter clumping into halos and subhalos, significantly enhances the annihilation signal and alters the thermal and ionization history of the IGM. This enhancement leads to a noticeable effect on the 21-cm signal, including a shift from absorption to emission as dark matter annihilation heats the IGM at lower redshifts. By incorporating observational noise from upcoming radio interferometers, particularly the Square Kilometer Array (SKA), we show that these effects remain detectable despite observational challenges. We find that the dark matter annihilation models can leave measurable imprints on the 21-cm signal distinguishable from the non-annihilation scenarios for the dark matter masses $m_{\mathrm{DM}}=100$ MeV and the annihilation cross-sections of $⟨\sigma v⟩\simeq 10^{-31}{\mathrm{cm}}^3/\mathrm{s}$ ($⟨\sigma v⟩\simeq 10^{-32}{\mathrm{cm}}^3/\mathrm{s}$ for $m_{\mathrm{DM}}=1$ MeV and $⟨\sigma v⟩\simeq 10^{-24}{\mathrm{cm}}^3/\mathrm{s}$ for $m_{\mathrm{DM}}=1$ TeV).

    ↳ astro-ph.COhep-phPRD(2025)·6 citations
32. 32*

    Generalized Landau Yang Theorem

    T.R. Govindarajan🇮🇳 · Rakesh Tibrewala🇮🇳

    Landau Yang theorem is well known for the past several decades. It prohibits the decay of a massive spin 1 particle to two photons. This emerges simply from the representation theory of the Poincare group and Bose Statistics. It does not require any action or Lagrangian. We generalize this theorem to theories with supersymmetry (SUSY) which disallows even decay to two photinos (Majorana fermions) as well as the decay of a zino to a photon and a photino. We will prove that if the photon has a mass, howsoever small, this theorem can be evaded. We also show that the supersymmetric selection rule above can also be evaded through the Stueckelberg mass term. Further interesting implications are also pointed out.

    ↳ hep-thgr-qchep-phJHEP(2020)·1 citation
33. 33*

    Probing for an IR-fixed Point in QCD by Superallowed Gamow-Teller Transitions in Doubly Magic Nuclei

    Mannque Rho🇫🇷 · Long-Qi Shao🇨🇳

    This brief note is to point out that the recent measurements at GSI and RIKEN of the superallowed Gamow-Teller transition in the doubly magic closed-shell nucleus ${}^{100}$Sn could give an indication for a possibly important {\it fundamental} quenching, thus-far unrecognized, of $g_A$, unambiguously distinct from nuclear correlation effects in the framework of nuclear effective field theory. The result, either confirmed or ruled out both experimentally and theory, can have strong impacts on nuclear physics vis-à-vis with nuclear effective field theory as well as on particle physics relevant for going beyond the Standard Model.

    ↳ nucl-thhep-ph2 citations
34. 34*

    The underlying black hole phase transitions in an Einstein-Maxwell-dilaton model with a holographic critical point

    Hong Guo🇧🇷 · Xiao-Mei Kuang🇨🇳 · Wei-Liang Qian🇨🇳

    The Einstein-Maxwell-dilaton model exhibits a first-order phase transition curve that terminates at a holographic critical endpoint, offering intriguing insights into the phase diagram of the dual system living on the boundary. However, the specific instability within the underlying spacetime that triggers the formation of the hairy black hole remains somewhat obscure. This raises the question of whether one of the hairy black hole phases represents a superconducting or scalarized state and how the two distinct phases merge into a indistinguishable one at the critical point. This work investigates the associated black hole phase transition and the underlying instabilities by exploring a specific Einstein-Maxwell-dilaton model. The approach aims to provide transparent insights into the black hole phase transitions in the bulk. By introducing a nonminimal coupling between a massive real scalar field and a Maxwell field in a five-dimensional anti-de Sitter spacetime, we identify two types of scalarization corresponding to tachyonic instabilities in the ultraviolet and infrared regions. These distinct instabilities lead to a first-order phase transition between two phases in the $\mu -T$ phase diagram. Furthermore, this first-order transition terminates at a critical point, beyond which the curve turns back, and the transition becomes a numerically elusive third-order one. Although one does not encounter a critical endpoint, the model still offers a consistent interpretation for the observed {\it cross-over} in the low baryon density region. We analyze the thermodynamic properties of the scalarized hairy black holes and discuss the implications of our findings.

    ↳ hep-thhep-phJHEP(2025)·3 citations
35. 35*

    Multi-Observatory Research of Young Stellar Energetic Flares (MORYSEF): X-ray Flare Related Phenomena and Multi-epoch Behavior

    Konstantin V. Getman (1)🇺🇸 · Eric D. Feigelson (1)🇺🇸 · Abygail R. Waggoner (2) · L. Ilsedore Cleeves (2) · Jan Forbrich (3) · Joe P. Ninan (4) · Oleg Kochukhov (5) · Vladimir S. Airapetian (6)🇺🇸 · Sergio A. Dzib (7) · Charles J. Law (2) · Christian Rab (8) ((1) Pennsylvania State University, (2) University of Virginia, (3) University of Hertfordshire, (4) Tata Institute of Fundamental Research, (5) Uppsala University, (6) NASA/GSFC/SEEC, (7) Max-Planck-Institut fur Radioastronomie, (8) Max-Planck-Institut fur Extraterrestrische Physik)

    The most powerful stellar flares driven by magnetic energy occur during the early pre-main sequence (PMS) phase. The Orion Nebula represents the nearest region populated by young stars, showing the greatest number of flares accessible to a single pointing of Chandra. This study is part of a multi-observatory project to explore stellar surface magnetic fields (with HET-HPF), particle ejections (VLBA), and disk ionization (ALMA) immediately following the detection of PMS super-flares with Chandra. In December 2023, we successfully conducted such a multi-telescope campaign. Additionally, by analyzing Chandra data from 2003, 2012, and 2016, we examine the multi-epoch behavior of PMS X-ray emission related to PMS magnetic cyclic activity and ubiquitous versus sample-confined mega-flaring. Our findings follow. 1) We report detailed stellar quiescent and flare X-ray properties for numerous HET/ALMA/VLBA targets, facilitating ongoing multi-wavelength analyses. 2) For numerous moderately energetic flares, we report correlations (or lack thereof) between flare energies and stellar mass/size (presence/absence of disks) for the first time. The former is attributed to the correlation between convection-driven dynamo and stellar volume, while the latter suggests the operation of solar-type flare mechanisms in PMS stars. 3) We find that most PMS stars exhibit minor long-term baseline variations, indicating the absence of intrinsic magnetic dynamo cycles or observational mitigation of cycles by saturated PMS X-rays. 4) We conclude that X-ray mega-flares are ubiquitous phenomena in PMS stars, which suggests that all protoplanetary disks and nascent planets are subject to violent high-energy emission and particle irradiation events.

    ↳ astro-ph.SRastro-ph.HEhep-phApJ(2024)·3 citations
36. 36*

    Quantum nature of gravity in a Bose-Einstein condensate

    Soham Sen🇮🇳 · Sunandan Gangopadhyay🇮🇳

    The effect of noise induced by gravitons on a Bose-Einstein condensate has been explored in (Phys. Rev. D 110 (2024) 026014; https://link.aps.org/doi/10.1103/PhysRevD.110.026014). In the previous paper, we investigated the effects of graviton while detecting a gravitational wave using a Bose-Einstein condensate. In this work we shall explicitly calculate the decoherence due to the noise of gravitons between two momentum states of the Bose-Einstein condensate. This decoherence happens due to Bremsstrahlung from the Bose-Einstein condensates due to the effect of the noise induced by gravitons. It is also observed that the two states become entangled because of the existence of a surrounding graviton field which degrades over time via means of this gravitational Bremsstrahlung. Using this property of the Bose-Einstein condensate in a quantum gravity background, we propose an experimental test via the use of atom lasers (generated from the condensate) which would, in principle, help to detect gravitons in future generations of very advanced ultra-cold temperature experiments.

    ↳ hep-thgr-qchep-phPRD(2025)·2 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.