Tue·Oct 15, 2024Tuesday·October 15, 2024

1. 01*

   Exploring Non-Isotropic Lorentz Invariance Violation Through Sidereal Effect at DUNE

   Shashank Mishra🇮🇳 · Saurabh Shukla🇮🇳 · Lakhwinder Singh🇮🇳 · Venktesh Singh🇮🇳

   Lorentz Invariance Violation (LIV) presents an intriguing opportunity to investigate fundamental symmetries, with neutrinos serving as a particularly effective probe for this phenomenon. Long-baseline neutrino experiments, such as the Deep Underground Neutrino Experiment (DUNE), excel at exploring non-isotropic LIV, especially through the observation of sidereal effects. This study comprehensively examines the full parameter space of non-isotropic, non-diagonal LIV parameters with sidereal dependence, focusing on two distinct flux scenarios: a low-energy flux and a tau-optimized flux. Through this analysis, we derive more stringent constraints on LIV parameters. Our results indicate that DUNE may achieve enhanced sensitivity for some LIV parameters, exceeding all previously established limits and marking a significant advancement in the investigation of LIV.

   hep-ph1 citation
2. 02*

   Indirect production of doubly charmed tetraquarks $T_{cc}$ at high energy colliders

   Juan-Juan Niu🇨🇳 · Bin-Bin Shi🇨🇳 · Zheng-Kui Tao🇨🇳 · Hong-Hao Ma🇨🇳

   The indirect production mechanisms of doubly charmed tetraquark $T_{cc}$ through three decay channels, Higgs$/Z^0\to ⟨cc{⟩}_{\bar{3}}+\bar{c}+\bar{c}\to T_{cc}^{\bar{q}\overline{q^{\prime }}}+\bar{c}+\bar{c}$ and $W^{+}\to ⟨cc{⟩}_{\bar{3}}+\bar{c}+\bar{s}\to T_{cc}^{\bar{q}\overline{q^{\prime }}}+\bar{c}+\bar{s}$, are analyzed within the framework of nonrelativistic QCD. The intermediate $⟨cc{⟩}_{\bar{3}}$ diquark cluster in color antitriplet evolves into tetraquark components via the fragmentation process by trapping two light antiquarks ($\bar{q}$ and $\overline{q^{\prime }}$) from the vacuum. After the considered doubly charmed tetraquark components are summed, including $T_{cc}^{\bar{u}\bar{u}}$, $T_{cc}^{\bar{u}\bar{d}}$, $T_{cc}^{\bar{d}\bar{d}}$, $T_{cc}^{\bar{u}\bar{s}}$, and $T_{cc}^{\bar{d}\bar{s}}$, the decay widths, branching ratios, and produced events each year for the production of $T_{cc}$ can be predicted at LHC and CEPC, respectively. The differential distributions and two main sources of theoretical uncertainty are also discussed. The results show that the produced events each year for $T_{cc}$ via $W^{+}$ decays is $1.80\times 10^5$, nearly $2$ orders of magnitude larger than that by Higgs decays ($1.11\times 10^3$) and $Z^0$ decays ($4.81\times 10^3$) at LHC. However at CEPC, the largest contribution for the production of $T_{cc}$ is through $Z^0$ decays, about $1.63\times 10^6$. There are only $4.79\times 10^{-1}$ and $2.03\times 10^2$ $T_{cc}$ events produced each year at CEPC through Higgs and $W^{+}$ decay, respectively.

   hep-phPRD(2025)·8 citations
3. 03*

   Scrutinizing $B^0$-meson flavor changing neutral current decay into scalar $K_0^{\ast }(1430)$ meson with $b\to s{\ell }^{+}{\ell }^{-}(\nu \bar{\nu })$ transition

   Yin-Long Yang🇨🇳 · Ya-Xiong Wang🇨🇳 · Hai-Bing Fu🇨🇳 · Tao Zhong🇨🇳 · Ya-Lin Song🇨🇳

   In this paper, we investigate the rare decay $B^0\to K_0^{\ast }(1430){\ell }^{+}{\ell }^{-}$ with $\ell =(e,\mu ,\tau )$ and $B^0\to K_0^{\ast }(1430)\nu \bar{\nu }$ induced by the flavor changing neutral current transition of $b\to s{\ell }^{+}{\ell }^{-}(\nu \bar{\nu })$. Firstly, the $B^0\to K_0^{\ast }(1430)$ transition form factors (TFFs) are calculated by using the QCD light-cone sum rule approach up to next-to-leading order accuracy. In which the $K_0^{\ast }(1430)$-meson twist-2 and twist-3 LCDAs have been calculated both from the SVZ sum rule in the background field theory framework and light-cone harmonic oscillator model. Then, we obtained the three TFFs at large recoil point, {\it i.e.,} $f_{+}^{B^0\to K_0^{\ast }}(0)=0.470_{-0.101}^{+0.086}$, $f_{-}^{B^0\to K_0^{\ast }}(0)=-0.340_{-0.068}^{+0.068}$, and $f_{\mathrm{T}}^{B^0\to K_0^{\ast }}(0)=0.537_{-0.115}^{+0.112}$. Meanwhile, we extrapolated TFFs to the whole physical $q^2$-region by using the simplified $z(q^2)$-series expansion. Furthermore, we calculate the $B^0\to K_0^{\ast }(1430){\ell }^{+}{\ell }^{-}(\nu \bar{\nu })$ decay widths, branching fractions, and longitudinal lepton polarization asymmetries of $B^0\to K_0^{\ast }(1430){\ell }^{+}{\ell }^{-}$, which lead to $\mathcal{B}(B^0\to K_0^{\ast }(1430)e^{+}{e}^{-})=(6.65_{-2.42}^{+2.52})\times 10^{-7}$, $\mathcal{B}(B^0\to K_0^{\ast }(1430){\mu }^{+}{\mu }^{-})=(6.62_{-2.41}^{+2.51})\times 10^{-7}$, $\mathcal{B}(B^0\to K_0^{\ast }(1430){\tau }^{+}{\tau }^{-})=(1.88_{-0.97}^{+1.10})\times 10^{-8}$, $\mathcal{B}(B^0\to K_0^{\ast }(1430)\nu \bar{\nu })=3.85_{-1.48}^{+1.55}\times 10^{-6}$ and the integrated longitudinal lepton polarization asymmetries $⟨A_{P_L}⟩=(-0.99,-0.96,-0.03)$ for the cases $\ell =(e,\mu ,\tau )$ respectively.

   hep-phEPJC(2025)·6 citations
4. 04*

   Chiral symmetry breaking, chiral partners, and the $K_1$ and $K^{\ast }$ in medium

   Su Houng Lee🇰🇷

   We clarify the concept of chiral partners. For a vector meson, the isospin-zero and hypercharge-zero state in the flavor octet mixes with the flavor singlet state. Since the flavor singlet vector meson does not have a chiral partner, the mixed $\omega$ and $\varphi$ mesons will not have chiral partners. This means that even when chiral symmetry is restored, these mesons will not become degenerate with their corresponding parity partners. On the other hand, the $K_1$ and $K^{\ast }$ mesons are chiral partners, and both have widths smaller than 100 MeV. Therefore, we emphasize that studying these mesons in environments where chiral symmetry is restored is particularly important for understanding the effect of chiral symmetry restoration on chiral partners and their masses.

   hep-phnucl-exnucl-thJ.Subatomic Part.Cosmol.(2024)·2 citations
5. 05*

   Neutrino production in the central dark-matter spikes of active galaxies

   Polina Kivokurtseva🇷🇺

   Recent multi-messenger observations suggest that high-energy neutrinos may be produced close to central black holes in active galaxies. These regions may host dark-matter (DM) spikes, where the concentration of DM particles is very high. Here we explore the contribution of the DM annihilation to the target photons for the neutrino production, proton-photon interactions, estimate the associated neutrino spectrum and figure out possible future tests of this scenario.

   hep-phastro-ph.HEEPJC(2025)·1 citation
6. 06*

   Quantum field theory and the electroweak Standard Model

   Gustavo Burdman🇧🇷

   In these lectures we give an introduction and overview of the electroweak standard model (EWSM) of particle physics. We first introduce the basic concepts of quantum field theory necessary to build the EWSM: abelian and non-abelian gauge theories, spontaneous symmetry breaking and the Higgs mechanism. We also introduce some basic concepts of renormalization, so as to be able to understand the full power of electroweak precision tests and their impact on our understanding the EWSM and its possible extensions. We discuss the current status of experimental tests and conclude by pointing the problems still existing in particle physics not solved by the EWSM and how these impact the future of the field.

   hep-phhep-exCERN Yellow Rep.School Proc.(2025)·3 citations
7. 07*

   Strong decay widths of S- and P-wave singly-, doubly- and triply-heavy charm and bottom baryons

   Emmanuel Ortiz-Pacheco🇸🇮 · Roelof Bijker🇲🇽

   We present a study of two-body decay widths of heavy baryons into another heavy baryon and a light pseudoscalar meson in the framework of the non-relativistic quark model in combination with the elementary emission model for the strong couplings. The present study includes the decays of 1S- and 1P-wave baryons with one, two or three heavy quarks, either charm (c) or bottom (b). The relative partial widths are given by the appropriate flavor SU(3) isoscalar factors. The flavor, spin and orbital contributions are discussed explicitly as well as selection rules for forbidden decays. The total widths are compared with the available experimental data as well as with other theoretical studies. The calculated widths of singly-heavy baryons are found to be in reasonable agreement with the observed widths. The decay widths of doubly-heavy baryons are suppressed with respect to those of the singly-heavy baryons by the ratios of the quark masses appearing in the orbital contributions.

   hep-phhep-exnucl-th9 citations
8. 08*

   Semileptonic and nonleptonic decays of $B_{u,d,s,c}^{\ast }$ in the covariant light-front approach

   Si-Yang Wang🇨🇳 · You-Ya Yang🇨🇳 · Zhi-Jie Sun🇨🇳 · Hao Yang🇨🇳 · Peng Li🇨🇳 · Zhi-Qing Zhang🇨🇳

   The semileptonic and nonleptonic decays of the b-flavor vector mesons $B_{u,d,s}^{\ast }$ and $B_c^{\ast }$ are investigated within the covariant light-front quark model (CLFQM). By calculating the form factors of the transitions $B_{u,d,s,c}^{\ast }\to P$ under the CLFQM, with $P$ denoting a pseudoscalar meson, i.e., $\pi ,K,{\eta }_c(1S,2S),D_{(s)},B_{(s)}$, we predict and discuss several physical observables, including the branching ratios, polarization fractions $f_L,f_{\Vert }$, and forward-backward asymmetries $A_{FB}$. The total widths of the single-photon radiative decay channels for these b-flavor vector mesons are estimated using their partial widths. In these considered decays, one can find that the semileptonic decays $B_s^{\ast 0}\to D_s^{-}{\ell }^{\prime +}{\nu }_{{\ell }^{\prime }}$ and $B_c^{\ast +}\to B_s^0{\ell }^{\prime +}{\nu }_{{\ell }^{\prime }},{\eta }_c{\ell }^{\prime +}{\nu }_{{\ell }^{\prime }}$, with ${\ell }^{\prime }$ being $e$ or $\tau$, and the nonleptonic channels $B_c^{\ast +}\to B_s^0{\pi }^{+},B_s^0{\rho }^{+}$ have the largest branching ratios, which can reach up to the $10^{-7}$ order, and are most likely to be accessible at the future high-luminosity LHCb and Belle-II experiments.

   hep-phCPC(2024)·7 citations
9. 09*

   Interplay between $M_W$, ${\Omega }_{\mathrm{CDM}}{h}^2$, and $(g-2{)}_{\mu }$ in Flavor Symmetry-Based Supersymmetric Models

   S. Israr🇵🇰 · M.E. Gomez🇪🇸 · M. Rehman🇵🇰 · Y. Arafat🇵🇰

   We study the phenomenological implications of the minimal supersymmetric standard model (MSSM) augmented by a non-abelian flavor symmetry labeled as sMSSM. Incorporating this flavor symmetry allows for a significant reduction in the original plethora of free parameters present in the MSSM, ultimately reducing them down to just seven in sMSSM. This reduction of free parameters is not achieved through ad hoc assumptions like in the constrained MSSM (CMSSM); rather, it is grounded in theoretical considerations. Our work focuses on exploring the interplay between the $W$ boson mass ($M_W$) predictions, the cold dark matter (CDM) relic abundance (${\Omega }_{\mathrm{CDM}}{h}^2$), and the $(g-2{)}_{\mu }$ anomaly. We identified correlations among the theoretical parameters arising from this interplay, which can be complemented by experimental constraints such as the Higgs boson mass, B-physics observables, and charge and color breaking minima. Additionally, our investigations show that the $(g-2{)}_{\mu }$ discrepancy and the Planck bounds on ${\Omega }_{\mathrm{CDM}}{h}^2$ can be addressed within the sMSSM, but only in a very narrow region of the parameter space.

   hep-phAdv.High Energy Phys.(2025)·2 citations
10. 10*

    In-depth Study of Spin- and Momentum-Dependent Interaction Potentials Between Two Spin-1/2 Fermions Mediated by Light Spin-0 Particles

    Yang Zhong🇨🇳 · Zhi-Hui Guo🇨🇳 · Hai-Qing Zhou🇨🇳

    We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles, in both momentum and coordinate spaces. Our calculation is based on the four-point Green function rather than the scattering amplitude. Among the sixteen potential components, eight that vanish in the non-relativistic limit are shown to acquire nonzero relativistic and off-shell corrections. In addition to providing relativistic and off-shell corrections to the operator basis commonly used in the literature, we introduce an alternative operator basis that facilitates the derivation of interaction potentials in coordinate space. Furthermore, we calculate both the long-range and short-range components of the potentials, which can be useful for future experimental analyses at both macroscopic and atomic scales.

    hep-phphysics.atom-phCommun.Theor.Phys.(2025)·1 citation
11. 11*

    Observability of 2HDM charged Higgs boson in a misaligned scenario

    Majid Hashemi🇮🇷 · Omid Seify🇮🇷

    The large hadron collider precision measurement of $h_{125}$ properties suggests that a misaligned two Higgs doublet model type 1 is preferred among other types of the model. In this analysis, a lepton collider potential for charged Higgs boson observation is evaluated and compared with HL-LHC expectations. We focus on $H^{\pm }\to W^{\pm }{h}_{125}$ decay which is exclusively activated in misalignment scenario. An event analysis including fast detector simulation is performed and it is shown that some parts of the parameter space which are out of HL-LHC reach can be probed by a high energy lepton collider with signal significance exceeding $2\sigma$ and $5\sigma$ for exclusion or discovery. The region with highest sensitivity is in the middle range charged Higgs boson mass, i.e., $350<m_{H^{\pm }}<450$ GeV and $\tan \beta \gtrsim 4$ at non-zero $\cos (\beta -\alpha )$ values.

    hep-phPRD(2025)·3 citations
12. 12*

    QCD sum rule analysis of $0^{+}$ four-quark states

    Shuang-Hong Li🇨🇳 · Ze-Sheng Chen🇨🇳 · Yi-Xin Chen🇨🇳 · Hong-Ying Jin🇨🇳

    We present a comprehensive QCD sum rules analysis at next-to-leading order for all types of $J^P=0^{+}$ four-quark states composed of $u$, $d$, and $s$ quarks. The eigenvectors of the renormalization matrix are chosen to be the renormalized four-quark operators, which can be equally interpreted as tetraquark or molecule operators. Meanwhile, the typical nonet masses given by bare tetraquark operators are lower than those given by bare molecule operators. Most of the nonet masses are around $1-2\text{GeV}$, and they can be interpreted as the $0^{+}$ mesons observed in experiments. We find a category of four-quark nonets with masses $\lesssim 1\text{GeV}$, potentially corresponding to the light $0^{+}$ mesons $f_0(500)$, $K_0^{\ast }(700)$, $f_0(980)$, and $a_0(980)$. On the other hand, the possible 27-fold states are heavier than most of the nonets, with masses $\gtrsim 2\text{GeV}$. The main uncertainty arises from the factorization of high-dimensional condensates, which usually underestimates their values. To address this, we introduce deviation factors for the dimension-6, -8, and -10 condensates, and vary them over a wide range to obtain conservative estimates of the $0^{+}$ four-quark state masses. Some general properties of the $0^{+}$ light four-quark states can be derived that do not rely on precise numerical values. We also find that the ambiguity in the factorization of the dimension-8 condensate can introduce a larger discrepancy than previously estimated. As a byproduct, we propose a simple trick for renormalizing multi-quark operators at the one-loop level.

    hep-ph4 citations
13. 13*

    EPOS4: New theoretical concepts for modeling proton-proton and ion-ion scattering at very high energies

    Klaus Werner🇫🇷

    I explain the new concepts underpinning EPOS4, a novel theoretical framework designed to model hadronic interactions at ultrarelativistic energies. This approach eventually reconciles the parallel multiple scattering scenario (needed in connection with collective effects) and factorization (being the conventional method for high-energy scattering).

    hep-ph10 citations
14. 14*

    All-loop renormalization group invariants for MSSM

    Daniil Rystsov🇷🇺 · Konstantin Stepanyantz🇷🇺

    For MSSM from the gauge couplings, Yukawa couplings, and the coefficient $\mu$ in the part of superpotential quadratic in the Higgs superfields we construct combinations which (for certain renormalization prescriptions) do not depend on the renormalization point in all loops. In other words, these combinations are the renormalization group invariants. Similar invariants are also constructed for NMSSM. The derivation is based on the nonrenormalization of the superpotential and the NSVZ equations. We argue that the scale invariance of the considered combinations takes place in the class of the HD+MSL schemes. This fact has been verified in the lowest orders, up to and including the one in which the dependence on the renormalization prescription becomes essential. It is also demonstrated that in the $\overline{\text{mbox}DR}$ scheme the renormalization group invariance does not take place starting from the approximation, where the scheme dependence manifests itself.

    hep-phhep-thPRD(2025)·4 citations
15. 15*

    Pentaquarks $P_c$ in a dynamical coupled-channel approach of $\gamma p\to J/\psi p$ reaction

    Xu Zhang🇨🇳

    We construct a dynamical coupled-channel approach to photon-induced $J/\psi$ production to search for the trace of the pentaquarks $P_c$. In this approach, the considered open-charm intermediate states are ${\Lambda }_c{\bar{D}}^{(\ast )}$ and ${\Sigma }_c{\bar{D}}^{(\ast )}$. Scattering amplitude involving ${\Lambda }_c{\bar{D}}^{(\ast )}$, ${\Sigma }_c{\bar{D}}^{(\ast )}$ and $J/\psi p$ interactions is calculated from solving a set of coupled-channel integral equations. The coupled-channel interaction potentials are generated from one-boson-exchange. The pentaquarks $P_c$ are dynamically generated from the coupled-channel interactions. Moreover, the background contributions to the $P_c$ signals are assumed to be the Pomeron exchange and $\sigma$ exchange. The predicted total and differential cross sections of $J/\psi$ photoproduction are within the range of the data from the GlueX and $J/\psi$-$007$ experiments. It is found that the $\sigma$ exchange plays a crucial role for determining the very near threshold cross section. The total cross section gets enhanced due to the open-charm state rescattering in the $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$ production regions, and is of order 1 nb.

    hep-phhep-exnucl-thEPJC(2025)·10 citations
16. 16*

    Correlations and fluctuations in a magnetized PNJL model with and without inverse magnetic catalysis effect

    Shijun Mao🇨🇳

    The correlation ${\chi }_{11}^{BQ}$ and quadratic fluctuations ${\chi }_2^B,{\chi }_2^Q,{\chi }_2^T$ of baryon number $B$, electric charge $Q$ and temperature $T$ are investigated in a two-flavor Polyakov loop extended Nambu-Jona-Lasinio (PNJL) model at finite temperature and magnetic field. The inverse magnetic catalysis (IMC) effect is introduced through the magnetic field dependent parameters $G(eB)$ or $T_0(eB)$, and we make comparison of the results in the cases with and without IMC effect. With nonvanishing magnetic field, the correlation ${\chi }_{11}^{BQ}$ and fluctuations ${\chi }_2^B,{\chi }_2^Q,{\chi }_2^T$ increase with temperature, and then show the peak around the pseudocritical temperatures of chiral restoration and deconfinement phase transitions in the cases with and without the IMC effect. The correlation and fluctuations along the phase transition line under external magnetic field are characterized by the scaled correlation ${\hat{\chi }}_{11}^{BQ}=\frac{{\chi }_{11}^{BQ}(eB,T_{pc}^c(eB))}{{\chi }_{11}^{BQ}(eB=0,T_{pc}^c(eB=0))}$ and scaled fluctuations ${\hat{\chi }}_2^{B(Q,T)}=\frac{{\chi }_2^{B(Q,T)}(eB,T_{pc}^c(eB))}{{\chi }_2^{B(Q,T)}(eB=0,T_{pc}^c(eB=0))}$ at the pseudocritical temperature $T_{pc}^c$ of chiral restoration phase transition. ${\hat{\chi }}_{11}^{BQ},{\hat{\chi }}_2^B$, and ${\hat{\chi }}_2^Q$ increase with magnetic fields, and the inclusion of IMC effect leads to some enhancement in their values. However, ${\hat{\chi }}_2^T$ is altered by the IMC effect. Without IMC effect, ${\hat{\chi }}_2^T$ slightly increases and then decreases with magnetic fields. Taking into account of the IMC effect by $G(eB)$, ${\hat{\chi }}_2^T$ monotonically increases with magnetic fields, and by $T_0(eB)$, it is a nonmonotonic function of magnetic field.

    hep-phhep-latnucl-thCPC(2025)·10 citations
17. 17*

    Charged Lepton Flavour Violating Meson Decays in Seesaw Models

    Pravesh Chndra Awasthi🇮🇳 · Jai More🇮🇳 · Akhila Kumar Pradhan🇮🇳 · Kumar Rao🇮🇳 · Purushottam Sahu🇮🇳 · S. Uma Sankar🇮🇳

    The occurrence of neutrino oscillations demands the existence of flavour violation in charged lepton sector. The relation between the branching ratios of different charged lepton flavour violating (CLFV) decay modes depends on the details of the neutrino mass model. In this work, we consider the three types of simple seesaw mechanisms of neutrino masses and study the correlation between the radiative CLFV decays and the meson CLFV decays. We find that the meson CLFV decay branching ratios are negligibly small in type-II seesaw mechanism whereas they are constrained to be at least three (two) orders of magnitude smaller than the radiative CLFV decay branching ratios in the case of type-I (type-III) seesaw mechanism. Thus the relationship between these two modes of CLFV decays helps in distinguishing between different types of seesaw mechanism. If, the branching ratios of CLFV decays of mesons are larger than those of radiative CLFV decays, it provides a strong hint that the neutrino mass generating mechanism is more complicated than simple seesaw.

    hep-phJHEP(2025)·2 citations
18. 18*

    Global fit to the 2HDM with generic sources of flavour violation using \textsf{GAMBIT}

    Peter Athron🇨🇳 · Andreas Crivellin🇨🇭 · Tomás E. Gonzalo🇩🇪 · Syuhei Iguro🇯🇵 · Cristian Sierra🇨🇳

    We perform a global statistical analysis of the two-Higgs-doublet model with generic sources of flavour violation using \textsf{GAMBIT}. This is particularly interesting in light of deviations from the Standard Model predictions observed in $b\to c\tau \bar{\nu }$ and $b\to s{\ell }^{+}{\ell }^{-}$ transitions as well as the indications for a charged Higgs with a mass of 130\,GeV in top quark decays. Including all relevant constraints from precision, flavour and collider observables, we find that it is possible to simultaneously explain both the charged and neutral current $B$ anomalies. We study the impact of using different values for the $W$ mass and the Standard Model prediction for $g-2$ of the muon and provide predictions for observables that can probe our model in the future such as lepton flavour violation searches at Belle II and Higgs coupling strength measurements at the high-luminosity LHC.

    hep-phJHEP(2024)·17 citations
19. 19*

    Comment on "A try for dark energy in quantum field theory: The vacuum energy of neutrino field"

    James M. Cline🇨🇦

    It was recently suggested (arxiv:2410.06604) that the small value of the dark energy of the universe could be explained in terms of the scale of neutrino masses through a simple quantum field theoretic mechanism. I clarify that the quantity computed is only a threshold correction to the vacuum energy at the low $m_{\nu }$ scale, and therefore cannot explain the magnitude of the vacuum energy.

    hep-phastro-ph.COgr-qc1 citation
20. 20*

    Prospects for measuring quark polarization and spin correlations in $b\bar{b}$ and $c\bar{c}$ samples at the LHC

    Yevgeny Kats🇮🇱 · David Uzan🇮🇱

    Polarization and spin correlations have been explored very little for quarks other than the top. Utilizing the partial preservation of the quark's spin information in baryons in the jet produced by the quark, we examine possible analysis strategies for ATLAS and CMS to measure the quark polarization and spin correlations in $pp\to q\bar{q}$ processes. We find polarization measurements for the $b$ and $c$ quarks to be feasible, even with the currently available datasets. Spin correlation measurements for $b\bar{b}$ are possible using the CMS Run 2 parked data, while such measurements for $c\bar{c}$ will become possible with higher integrated luminosity. We also provide leading-order QCD predictions for the polarization and spin correlations expected in the $b\bar{b}$ and $c\bar{c}$ samples with the relevant cuts. These proposed analyses can provide new information on the polarization transfer from quarks to baryons, measure entanglement and Bell nonlocality in the $b\bar{b}$ final state, and might even be sensitive to physics beyond the Standard Model.

    hep-phPoS(2025)·1 citation
21. 21*

    A Spin One Bottomonium Study in the Functional Formalism in the Feynman Gauge

    Vladimir Sauli🇨🇿

    The Bethe-Salpeter equation for spin-one bottomonium coupled to quark and gluon propagators is solved in a class of non-trivial linear gauges. The interaction kernel is based on a known gluon propagator extrapolated from the lattice and contains only small amount of additional phenomenology. The first numerical results are obtained in the Feynman gauge where the associated problem with infrared divergences is circumvented by by introducing a symmetry breaking regulator mass $m_L$. The presence of this mass renders the bound state vertices of vector states finite but it is also necessary to prevent inconsistent solutions of the bound state equation. For $m_L\simeq {\Lambda }_{QCD}$ it gives us good agreement with the experimental data for vector and axial vector bottomonia below the $BB$ threshold. While the primary concern pertains to the physical ramifications of the proposed concept, a potential origin for the proposed interaction is also presented.

    hep-ph1 citation
22. 22*

    Double strangeness pentaquarks and other exotic hadrons in the ${\Xi }_b\to \Xi J/\Psi \varphi$ decay

    J.A. Marsé-Valera🇪🇸 · V.K. Magas🇪🇸 · A. Ramos🇪🇸

    We study the possibility that four $\Xi$ resonances $(\Xi (1620)$, $\Xi (1690)$, $\Xi (1820)$, $\Xi (1950))$ could correspond to pentaquark states, in the form of meson-baryon bound systems. We also explore the possible existence of doubly strange pentaquarks with hidden charm $(P_{css})$ and find two candidates structured in a similar form, at energies of $4493\mathrm{MeV}$ and $4630\mathrm{MeV}$. The meson-baryon interaction is built from t-channel meson exchange processes which are evaluated using effective Lagrangians. Moreover we analyse the ${\Xi }_b\to \Xi J/\psi \varphi$ decay process, which permits exploring the existence of the heavy double strange pentaquark, as well as other exotic hadrons, in the three different two-body invariant mass spectra of the emitted particles. In the $J/\psi \varphi$ mass spectrum, we analyse the nature of the $X(4140)$ and $X(4160)$ resonances. In the $J/\psi \Xi$ invariant mass spectrum, we study the signal produced by the doubly strange pentaquark, where we conclude that it has a good chance to be detected in this reaction if its mass is around $4580-4680\mathrm{MeV}$. Finally, in the $\varphi \Xi$ spectrum we study the likelihood to detect the $\Xi (2500)$ state.

    hep-phPRD(2025)·5 citations
23. 23*

    Effective two-loop background contributions to $g_e-2$

    Jason L. Evans🇨🇳 · Jun-Yuan Lyu🇨🇳

    Recent work has shown the utility of examining background effects from ultralight dark matter on precision measurements. This effect enhances seemingly benign contributions to the level that experiments are sensitive to them. In this work, we examine the consequences of the effective axion-like particles coupling to photons in a background of axion-like particle dark matter. This analysis leads to new constraints on the product of the axion electron and axion photon coupling. Furthermore, since the axion photon coupling is generated, at one loop, by a pseudoscalar Yukawa coupling, this calculation can also be applied to constraining the axion-like particles coupling to the electron at the two-loop level. This contribution often dominates due to the fact that the one-loop contribution to the anomalous magnetic moment of the electron from a pseudoscalar is momentum suppressed.

    hep-ph6 citations
24. 24*

    General Signals for Charged Lepton Flavor Violating Decays

    Spencer Chang🇺🇸 · Thomas Driscoll🇺🇸

    We explore the most general phenomenology of charged lepton flavor violating (CLFV) decays of muon and tau leptons to the three body final states $(\bar{e}ee,\bar{\mu }\mu \mu ,\bar{e}\mu \mu ,\bar{\mu }\mu e,\bar{\mu }ee,\bar{e}e\mu )$. By constructing a complete basis of operators at each dimension, we derive the most general amplitudes for these decay processes. By considering constraints from unitarity and LEP, we show that operators of mass dimension 6 and 7 are the most likely to be observed in next generation experiments. Focusing on these dimensions, we compute the results of unpolarized (spin-averaged) decays parameterized in terms of the invariant masses of the daughter particles. We also compute the differential decay rates for polarized decays, in anticipation of the experimental search Mu3e, which expects to have a muon beam with $\sim 90\%$ polarization, and the Chiral Belle proposal, which aims to have a $70\%$ polarized electron beam. To determine the extent to which the operators may be distinguished experimentally, we plot the differential distributions for each operator, showing that they leave only a few possible degenerate explanations. Through a statistical analysis, we estimate the number of events needed to break the degeneracies using the angular information. These results are adapted to treat $\ell \to {\ell }^{\prime }\nu \bar{\nu }$, where the angular distribution of the outgoing charged lepton has enhanced distinguishing power. With many Standard Model extensions predicting these CLFV decays, these results will better enable upcoming searches to identify and/or constrain physics beyond the Standard Model.

    hep-phhep-exPRD(2025)·2 citations
25. 25*

    From Supernovae to Neutron Stars: A Systematic Approach to Axion Production at Finite Density

    Konstantin Springmann🇮🇱 · Michael Stadlbauer🇩🇪 · Stefan Stelzl🇨🇭 · Andreas Weiler🇩🇪

    We present a systematic study of QCD axion production in environments with finite baryon density and temperature, implying significant changes to axion phenomenology. Within heavy baryon chiral perturbation theory, we derive the effective Lagrangian describing axion interactions with nucleons and mesons up to next-to-leading-order in the chiral expansion. We focus on corrections to the axion-nucleon couplings from higher orders and finite density. These couplings are modified by up to an order of magnitude near nuclear saturation density, significantly impacting axion production in supernovae and neutron stars. Density-dependent corrections enhance the axion luminosity in supernovae by an order of magnitude, strengthening current best bounds by a factor of three. We stress the importance of including all axion production channels up to a given chiral order for a consistent luminosity calculation and classify the missing contributions up to the third chiral order. The modified axion-nucleon couplings also affect neutron star cooling rates via axion emission. A re-evaluation of existing neutron star cooling bounds, constrained to regions where perturbative control is reliable, weakens these bounds by a factor of four. Lastly, our results have implications for terrestrial axion searches that rely on precise knowledge of axion-nucleon couplings.

    hep-phastro-ph.HEnucl-thJHEP(2025)·42 citations
26. 26*

    Constraints on Covariant Horava-Lifshitz Gravity from precision measurement of planetary gravitomagnetic field

    Li-dong Zhang🇨🇳 · Li-Fang Li🇨🇳 · Peng Xu🇨🇳 · Xing Bian🇨🇳 · Ziren Luo🇨🇳

    As a generalization of Einstein's theory, Horava-Lifshitz has attracted significant interests due to its healthy ultraviolet behavior. In this paper, we analyze the impact of the Horava-Lifshitz corrections on the gravitomagnetic field. We propose a new planetary gravitomagnetic field measurement method with the help of the space-based laser interferometry, which is further used to constrain the Horava-Lifshitz parameters. Our analysis shows that the high-precision laser gradiometers can indeed limit the parameters in Horava-Lifshitz gravity and improve the results by one or two orders when compared with the existing theories. Our novel method provides insights into constraining the parameters in the modified gravitational theory, which facilitates a deeper understanding of this complex framework and paving the way for potential technological advancements in the field.

    ↳ gr-qchep-phhep-thCPC(2025)·0 citations
27. 27*

    Kantowski-Sachs cosmological model with axion-like scalar field and dark energy

    Maxim Krasnov🇷🇺 · Oem Trivedi🇮🇳 · Maxim Khlopov🇫🇷

    We consider Axion-like particle (ALP) model to construct numerical spatially homogeneous anisotropic Kantowski-Sachs cosmological model. We present various analytical and numerical results in this regard, discussing the evolution of various important cosmological parameters in this regard with ALP scalar field. We also present some general results for generic scalar field in a Kantowski-Sachs background.

    ↳ gr-qchep-ph1 citation
28. 28*

    On Two Nucleons Near Unitarity with Perturbative Pions

    Yu Ping Teng (U. of Wisconsin-Madison and George Washington University)🇺🇸 · Harald W. Griesshammer (George Washington U.)🇺🇸

    We explore the impact of perturbative pions on the Unitarity Expansion in the two-nucleon S-waves of Chiral Effective Field Theory at next-to-next-to leading order. Pion exchange explicitly breaks the nontrivial fixed point's universality and invariance under conformal and Wigner-$\text{SU}(4)$ spin-isospin transformations. This Chiral Effective Field Theory applies tothe Unitarity Window (45deg<delta(k)<135deg,$k\approx m_{\pi }$) most relevant for low-energy nuclear systems. Its only LO scale is the scattering momentum; NLO adds only scattering length, effective range and non-iterated one-pion exchange (OPE); and N2LO only once-iterated OPE. Agreement in the 1S0 channel is very good. Apparent large discrepancies in the 3S1 channel at k>100MeV are remedied by taking only the central part of the pion's N2LO contribution. In contradistinction to the tensor part, it is invariant under Wigner-SU(4)symmetry and hence identical in 1S0 and 3S1. NLO pions are Wigner-invariant. Both channels describe PWAs and pole parameters well within mutually consistent quantitative theory uncertainty estimates. Pionic effects are small, even for k>mpi. Empirically determined breakdown scales agree well with ${\Lambda }_{NN}=\frac{16\pi f_{\pi }^2}{g_A^{2}M}=300$MeV where iterated OPE is not suppressed. We therefore conjecture: The footprint of both scale invariance and Wigner-symmetry in the Unitarity Expansion shows persistence,i.e. both dominate even for k=mpi and are more relevant than chiral symmetry,so that the tensor/Wigner-SU(4) symmetry-breaking part of OPE does not enter before N3LO. We also discuss the potential relevance of entanglement power and possible resolution of a conflict with the strength of the tensor interaction in the large-Nc expansion.

    ↳ nucl-thhep-phEPJA(2025)·6 citations
29. 29*

    Connecting Inflation to the NANOGrav 15-year Data Set via Massive Gravity

    Ved Kenjale🇺🇸 · Tina Kahniashvili🇺🇸

    Several pulsar timing array (PTA) missions have reported convincing evidence of a stochastic gravitational wave background within their latest datasets. This background could originate from an astrophysical source, though there are multiple possibilities for its origin to be cosmological. Focusing on the NANOGrav signal, which was in good agreement with other PTAs, we evaluate the possibility of an inflationary source for the background. However, we'll consider a time-dependent minimal theory of massive gravity instead of standard general relativity for our analysis. We find that an inflationary interpretation will require a strongly blue spectrum, characterized by $n_T=1.8\pm 0.54$, while Big Bang Nucleosynthesis limits will require a low reheating scale of $T_{\text{rh}}\simeq 4000\text{GeV}$. Though these constraints make it difficult for inflation to be the source of the NANOGrav signal, we find that the massive gravity model allows for a greater reheating temperature than standard general relativity, making an inflationary interpretation slightly less cumbersome.

    ↳ astro-ph.COgr-qchep-phPRD(2025)·5 citations
30. 30*

    Polarization Characteristics of the Hyperactive FRB 20240114A

    Jin-Tao Xie · Yi Feng · Di Li · Yong-Kun Zhang · Dengke Zhou · Yuanhong Qu · Xianghan Cui · Jianhua Fang · Jiaying Xu · Chenchen Miao · Mao Yuan · Chao-Wei Tsai and 5 other authors

    Fast radio bursts (FRBs) are transient radio bursts of extragalactic origin characterized by millisecond durations and high luminosities. We report on observations of FRB 20240114A conducted with the Robert C. Byrd Green Bank Telescope (GBT) at frequencies ranging from 720 to 920 MHz. A total of 437 bursts were detected, with a single observation recording 365 bursts over 1.38 hours, corresponding to a burst rate of 264 bursts per hour. The average rotation measures (RMs) were $347.0\pm 1.0$ rad m${}^{-2}$ on February 23, 2024, and $353.7\pm 0.6$ rad m${}^{-2}$ on March 1, 2024. Of the 301 bursts with detected RMs, 81% have a linear polarization fraction greater than 90%, and 14% exhibit circular polarization with a signal-to-noise ratio $>5$. Our sample also displayed polarization angle swings. We compared the linear polarization fraction of FRB~20240114A with those of the repeating sources FRB~20201124A and FRB~20220912A. Our analysis reveals that all three exhibit similar distributions in both linear and circular polarization fractions. These results indicate that the three sources share the same radiation mechanism. We analyze the fluence and waiting-time distributions of FRB~20240114A, revealing a right-skewed fluence distribution and a bimodal waiting-time structure, suggesting intrinsic emission timescales and potential multiple burst populations. Additionally, We present a novel method to determine the frequency range of bursts based on their spectral characteristics. This algorithm is independent of spectral models and remains unaffected by the removal of interference-affected channels in the data, ensuring robust performance.

    ↳ astro-ph.HEhep-phAstrophys.J.Suppl.(2025)·19 citations
31. 31*

    Top quark properties measurements and searches at ATLAS and CMS

    Sebastian Wuchterl (on behalf of the CMS Collaboration)🇨🇭

    Theoretical predictions for processes involving top quarks, such as top quark-antiquark pair production, depend on fundamental standard model (SM) parameters like the top quark mass or potentially receive contributions from beyond-the-SM (BSM) physics. By comparing predictions with measurements performed at the ATLAS and CMS experiments, SM parameters can be determined precisely, or measurements can be used as a powerful probe for BSM physics. In these proceedings, recent results measuring SM and top quark properties are reported, as well as new results of searches for BSM physics for charged lepton flavor violation, flavor changing neutral currents, and baryon number violation are presented.

    ↳ hep-exhep-ph1 citation
32. 32*

    Scale-dependence in $\Lambda$CDM parameters inferred from the CMB: a possible sign of Early Dark Energy

    Jun-Qian Jiang🇨🇳

    The early dark energy (EDE) model is one of the promising solutions to the Hubble tension. One of the successes of the EDE model is that it can provide a similar fit to the $\Lambda$CDM model for the CMB power spectrum. In this work, I analyze the phenomenology of the EDE and $\Lambda$CDM parameters on the CMB temperature power spectrum and notice that this cannot hold on all scales. Thus, if the real cosmology is as described by the EDE model, the $\Lambda$CDM parameters will be scale-dependent when fitting the CMB power spectrum with the $\Lambda$CDM model, which can be hints for the EDE model. I examine CMB-S4-like observations through mock data analysis and find that parameter shifts are notable. As observations include smaller scales, I find lower $H_0$, $n_s$, ${\omega }_b$ and higher ${\omega }_m$, $A_s{e}^{-2\tau }$, which will also constitute new tensions with other observations. They can serve as a possible signal for the EDE model.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2025)·10 citations
33. 33*

    The effect of multiple extra dimensions on the maximal mass of compact stars in Kaluza-Klein space-time

    Anna Horváth🇭🇺 · Emese Forgács-Dajka🇭🇺 · Gergely Gábor Barnaföldi🇭🇺

    Compact stars in the Kaluza-Klein space-time are investigated, with multiple additional compactified spatial dimensions ($d$). Within the extended phenomenological model, a static, spherically symmetric solution is considered, with the equation of state provided by a zero temperature, interacting multi-dimensional Fermi gas. The maximal masses of compact stars are calculated for different model parameters. We investigated the effect of the existence of multiple extra compactified dimensions within the Kaluza-Klein compact star structure. We found that the number of extra dimensions plays a similar role, and to a similar order, as the excitation number: increasing their number, $d$, reduces the maximal mass by a few percent.

    ↳ gr-qchep-phInt.J.Mod.Phys.A(2025)·2 citations
34. 34*

    Gamma-ray bursts and kilonovae from the accretion-induced collapse of white dwarfs

    Patrick Chi-Kit Cheong🇺🇸 · Tetyana Pitik🇺🇸 · Luís Felipe Longo Micchi · David Radice🇺🇸

    We present the first seconds-long 2D general relativistic neutrino magnetohydrodynamic simulations of accretion-induced collapse (AIC) in rapidly rotating, strongly magnetized white dwarfs (WDs), which might originate as remnants of double-WD mergers. This study examines extreme combinations of magnetic fields and rotation rates, motivated both by the need to address the limitations of 2D axisymmetric simulations and to explore the physics of AIC under rare conditions that, while yet to be observationally confirmed, may be consistent with current theoretical models and account for unusual events. Under these assumptions, our results demonstrate that, if realizable, such systems can generate relativistic jets and neutron-rich outflows with properties consistent with long gamma-ray bursts (LGRBs) accompanied by kilonovae, such as GRB 211211A and GRB 230307A. These findings highlight the potential role of AIC in heavy $r$-process element production and offer a framework for understanding rare LGRBs associated with kilonova emission. Longer-duration 3D simulations are needed to fully capture magnetic field amplification, resolve instabilities, and determine the fate of the energy retained by the magnetar at the end of the simulations.

    ↳ astro-ph.HEhep-phApJL(2025)·42 citations
35. 35*

    Disclosing the catalog pulsars dominating the Galactic positron flux

    Luca Orusa🇺🇸 · Silvia Manconi🇫🇷 · Fiorenza Donato🇮🇹 · Mattia Di Mauro🇮🇹

    The cosmic-ray flux of positrons is measured with high precision by the space-borne particle spectrometer AMS-02. The hypothesis that pulsars and their nebulae can significantly contribute to the excess of the AMS-02 positron flux has been consolidated after the observation of a $\gamma$-ray emission at GeV and TeV energies of a few degree size around a few sources, that provide indirect evidence that electron and positron pairs are accelerated to very high energies from these sources. By modeling the emission from pulsars in the ATNF catalog, we find that combinations of positron emission from cataloged pulsars and secondary production can fit the observed AMS-02 data. Our results show that a small number of nearby, middle-aged pulsars, particularly B1055-52, Geminga (J0633+1746), and Monogem (B0656+14), dominate the positron emission, contributing up to 80\% of the flux at energies above 100 GeV. From the fit to the data, we obtain a list of the most important sources for which we recommend multi-wavelength follow-up observations, particularly in the $\gamma$-ray and X-ray bands, to further constrain the injection and diffusion properties of positrons.

    ↳ astro-ph.HEhep-phJCAP(2025)·14 citations
36. 36*

    Reconstructing inflationary potential from NANOGrav 15-year Data: A robust study using Non-Bunch Davies initial condition

    Sayantan Choudhury🇮🇳

    We discuss the theoretical framework behind reconstruction of a generic class of inflationary potentials for canonical single-field slow-roll inflation in a model-independent fashion. The Non-Bunch Davies (NBD) initial condition is an essential choice to determine the structure of potential and to accommodate the blue-tilted tensor power spectrum feature recently observed in NANOGrav. Using the reconstruction technique we found the favoured parameter space which supports blue tilted tensor power spectrum. The validity of the EFT prescription in inflation is also maintained through the use of a new field excursion formula while keeping the necessary and sufficient conditions on the sub-Planckian field values in check. We find that the reconstructed potential display inflection point behaviour, which has deeper connection with high energy physics.

    ↳ gr-qcastro-ph.COhep-phhep-thJHEAp(2024)·7 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.