Tue·Dec 5, 2023Tuesday·December 5, 2023

1. 01*

   Precise tests of the axion coupling to tops

   Anh Vu Phan🇳🇱 · Susanne Westhoff🇳🇱

   We present an in-depth analysis of axions and axion-like particles in top-pair production at the LHC. Our main goal is to probe the axion coupling to top quarks at high energies. To this end, we calculate the top-antitop cross section and differential distributions including ALP effects up to one-loop level. By comparing these predictions with LHC precision measurements, we constrain the top coupling of axion-like particles with masses below the top-antitop threshold. Our results apply to all UV completions of the ALP effective theory with dominant couplings to top quarks, in particular to DFSZ-like axion models.

   hep-phhep-exJHEP(2024)·22 citations
2. 02*

   Walls, bubbles and doom -- the cosmology of HEFT

   Rodrigo Alonso🇬🇧 · Juan Carlos Criado🇪🇸 · Rachel Houtz🇺🇸 · Mia West🇬🇧

   As experiment charts new territory at the electroweak scale, the enterprise to characterise all possible theories becomes all the more necessary. In the absence of new particles, this ambitious enterprise is attainable and has led to the Higgs Effective Field Theory (HEFT) as the most general characterising framework, containing the Standard Model Effective Field Theory (SMEFT) as a subspace. The characterisation of this theory space led to the dichotomy SMEFT vs. HEFT\SMEFT as the two possible realisations of symmetry breaking. The criterion to distinguish these two possibilities is non-local in field space, and phenomena which explore field space beyond the neighbourhood of the vacuum manifold are in a singular position to tell them apart. Cosmology allows for such phenomena, and this work focuses on HEFT\SMEFT, the less explored of the two options, to find that first order phase transitions with detectable gravitational wave remnants, domain wall formation and vacuum decay in the far, far distant future can take place and single out HEFT\SMEFT. Results in cosmology are put against LHC constraints, and the potential of future ground- and space-based experiments to cover parameter space is discussed.

   hep-phastro-ph.COJHEP(2024)·21 citations
3. 03*

   Maximising CP Violation in Naturally Aligned Two-Higgs Doublet Models

   Neda Darvishi🇬🇧 · Apostolos Pilaftsis🇬🇧 · Jiang-Hao Yu🇨🇳

   The Two-Higgs Doublet Model (2HDM) is a well-motivated theoretical framework that provides additional sources of CP Violation (CPV) beyond the Standard Model (SM). After studying the vacuum topology of a general (convex) 2HDM potential, we unambiguously identify three origins of CPV: (I) Spontaneous CPV (SCPV), where the vacuum manifold has at least two degenerate CPV minima disconnected by domain walls, (ii) Explicit CPV (ECPV) with one single CPV ground state, and (iii) Mixed Spontaneous and Explicit CPV (MCPV), where the theory possesses more than one $non$-degenerate CPV local minimum. Most importantly, we define a novel complex parameter $r_{\mathrm{CP}}$ whose norm and phase control the three different realisations of CPV, at least at the tree level. In all these scenarios, only two CPV phases can be made independent, as any third CPV parameter will always be constrained via the CP-odd tadpole condition. Since ECPV vanishes in 2HDMs where SM Higgs alignment is achieved naturally through accidental continuous symmetries, we analyse the possibility of maximising CPV through soft and explicit breaking of these symmetries. We derive upper limits on key CPV parameters that quantify the degree of SM misalignment from constraints due to the non-observation of an electron Electric Dipole Moment (EDM). Finally, we delineate the CP-violating parameter space of the so-constrained naturally aligned 2HDMs that can further be probed at the CERN Large Hadron Collider (LHC).

   hep-phJHEP(2024)·17 citations
4. 04*

   Higgs Portal Interpretation of the Belle II $B^{+}\to K^{+}\nu \nu$ Measurement

   David McKeen🇨🇦 · John N. Ng🇨🇦 · Douglas Tuckler🇨🇦

   The Belle II experiment recently observed the decay $B^{+}\to K^{+}\nu \nu$ for the first time, with a measured value for the branching ratio of $(2.3\pm 0.7)\times 10^{-5}$. This result exhibits a $\sim 3\sigma$ deviation from the Standard Model (SM) prediction. The observed enhancement with respect to the Standard Model could indicate the presence of invisible light new physics. In this paper, we investigate whether this result can be accommodated in a minimal Higgs portal model, where the SM is extended by a singlet Higgs scalar that decays invisibly to dark sector states. We find that current and future bounds on invisible decays of the 125 GeV Higgs boson completely exclude a new scalar with a mass $\gtrsim 10$ GeV. On the other hand, the Belle II results can be successfully accommodated if the new scalar is lighter than $B$ mesons but heavier than kaons. We also investigate the cosmological implications of the new states and explore the possibility that they are part of an abelian Higgs extension of the SM. Future Higgs factories are expected to place stringent bounds on the invisible branching ratio of the 125 GeV Higgs boson, and will be able to definitively test the region of parameter space favored by the Belle II results.

   hep-phhep-exPRD(2024)·54 citations
5. 05*

   Explore the Nucleon Tomography through Di-hadron Correlation in Opposite Hemisphere in Deep Inelastic Scattering

   Yuxun Guo🇺🇸 · Feng Yuan🇺🇸

   We investigate the correlation of di-hadron productions between the current fragmentation region (CFR) and target fragmentation region (TFR) in deep inelastic scattering as a probe of the nucleon tomography. The QCD factorization and powering counting method are applied to compute the relevant diffractive parton distribution functions in the valence region. In particular, we show that the final state interaction effects lead to a nonzero longitudinal polarized quark distribution associated with the unpolarized nucleon target. This explains the observed beam single spin asymmetry (BSA) from a recent Jefferson Lab experiment. We further show that the BSA in the single diffractive hadron productions in the TFR, although kinematically suppressed, also exists because of the final state interaction effects.

   hep-phhep-ex10 citations
6. 06*

   $\sigma$ exchange in the one-boson exchange model involving the ground state octet baryons

   Bing Wu🇨🇳 · Xiong-Hui Cao🇨🇳 · Xiang-Kun Dong🇩🇪 · Feng-Kun Guo🇨🇳

   Based on the one-boson-exchange framework that the $\sigma$ meson serves as an effective parameterization for the correlated scalar-isoscalar $\pi \pi$ interaction, we calculate the coupling constants of the $\sigma$ to the ${\frac{1}{2}}^{+}$ ground state light baryon octet $\mathbb{B}$ by matching the amplitude of $\mathbb{B}\bar{\mathbb{B}}\to \pi \pi \to \bar{\mathbb{B}}\mathbb{B}$ to that of $\mathbb{B}\bar{\mathbb{B}}\to \sigma \to \bar{\mathbb{B}}\mathbb{B}$. The former is calculated using a dispersion relation, supplemented with chiral perturbation theory results for the $\mathbb{B}\mathbb{B}\pi \pi$ couplings and the Muskhelishvili-Omnès representation for the $\pi \pi$ rescattering. Explicitly, the coupling constants are obtained as $g_{NN\sigma }=8.7_{-1.9}^{+1.7}$, $g_{\Sigma \Sigma \sigma }=3.5_{-1.3}^{+1.8}$, $g_{\Xi \Xi \sigma }=2.5_{-1.4}^{+1.5}$, and $g_{\Lambda \Lambda \sigma }=6.8_{-1.7}^{+1.5}$. These coupling constants can be used in the one-boson-exchange model calculations of the interaction of light baryons with other hadrons.

   hep-phnucl-thPRD(2024)·13 citations
7. 07*

   $P$-wave states $T_{bb}^{-}$ from diquarks

   Zu-Hang Lin🇨🇳 · Chun-Sheng An🇨🇳 · Cheng-Rong Deng🇨🇳

   We investigate the $P$-wave states $T_{bb}^{-}$ in the isospin singlet and three excited modes [excitation occurring in the diquark $[bb{]}_{c_1}^{s_1}$ ($\rho$-mode), antidiquark $[\bar{u}\bar{d}{]}_{c_2}^{s_2}$ ($r$-mode) or between them ($\lambda$-mode)] from diquarks in a quark model. We analyze the dynamical behaviors of the diquark $[bb{]}_{c_1}^{s_1}$, antidiquark $[\bar{u}\bar{d}{]}_{c_2}^{s_2}$ and their correlations in the states $T_{bb}^{-}$ by decomposing the interactions from various sources in the model. The absolute dominant color-spin configuration, more than $99\%$, in the $\rho$-mode with $1^1{P}_1$ is $[bb{]}_{\bar{3}}^0[\bar{u}\bar{d}{]}_3^0$. Its energy is lower by about $18$ MeV than the threshold $\bar{B}\bar{B}$ so that it can establish a compact bound state. The chromomagnetic and meson-exchange interactions in the antidiquark $[\bar{u}\bar{d}{]}_3^0$ are responsible for its binding mechanism. Two other excited modes are higher than their respective threshold. The color configuration $6\otimes \bar{6}$ need to be handled discreetly in the tetraquark states.

   hep-phPRD(2024)·5 citations
8. 08*

   Probing quark orbital angular momentum at EIC and EicC

   Shohini Bhattacharya🇺🇸 · Duxin Zheng🇨🇳 · Jian Zhou🇨🇳

   We propose to detect signals from quark orbital angular momentum (OAM) through exclusive ${\pi }^0$ production in electron-(longitudinally-polarized) proton collisions. Our analysis demonstrates that the $\sin 2\varphi$ azimuthal angular correlation between the transverse momentum of the scattered electron and the recoil proton serves as a sensitive probe of quark OAM. Additionally, we present a numerical estimate of the asymmetry associated with this correlation for the kinematics accessible at EIC and EicC. This study aims to pave the way for the first experimental study of quark OAM in relation to the Jaffe-Manohar spin sum rule.

   hep-phPRL(2024)·36 citations
9. 09*

   Electromagnetic properties of the $T_{cc}^{+}$ molecular states

   Ya-Ding Lei🇨🇳 · Hao-Song Li🇨🇳

   In this work, we discuss the electromagnetic properties of the $S$-wave and $D$-wave $T_{cc}^{+}$ molecular states, which include the magnetic moments, transition magnetic moments and radiative decay widths. According to our results, the magnetic moment of $T_{cc}^{+}$ state observed experimentally is $-0.09{\mu }_N$. Meanwhile, we also discuss the relations between the transition magnetic moments of the $S$-wave $T_{cc}^{+}$ molecular states and the radiative decay widths, and we analyze the proportionality between the magnetic moments of the $T_{cc}^{+}$ molecular states. These results provide further information on the inner structure of $T_{cc}^{+}$ molecular states and deepen the understanding of electromagnetic properties of doubly charmed tetraquarks.

   hep-phPRD(2024)·11 citations
10. 10*

    A holographic study on QCD phase transition and phase diagram with two flavors

    Xin-Yi Liu🇨🇳 · Xiao-Chang Peng🇨🇳 · Yue-Liang Wu🇨🇳 · Zhen Fang🇨🇳

    We investigate the chemical potential effects of the equation of state and the chiral transition in an Einstein-Maxwell-dilaton-scalar system, which is obtained from an improved soft-wall AdS/QCD model coupled with an Einstein-Maxwell-dilaton system. The equations of state obtained from the model are in quantitative agreement with the lattice results at both zero and nonzero chemical potentials. The sensible chiral transition behaviors can be realized in the model. The QCD phase diagram with a CEP has also been obtained from the model.

    hep-phPRD(2024)·19 citations
11. 11*

    The electroweak magnetic monopole in the presence of KSVZ axion

    Tong Li🇨🇳 · Rui-Jia Zhang🇨🇳

    The Witten effect implies the dynamics of axion and magnetic monopole. The Cho-Maison monopole is a realistic electroweak monopole arisen in the Weinberg-Salam theory. This monopole of TeV scale mass motivates the dedicated search for electroweak monopole at colliders. In this work we investigate the implication of KSVZ axion for the electroweak magnetic monopole. We use the spherically symmetric ansatz for the electroweak dyon and introduce the spherically symmetric function for the axion field. The effective Lagrangian is then shown in terms of the electroweak monopole part, the axion kinetic energy as well as the axion interaction term. We derive the consequent equations of motion in the presence of the axion-photon coupling and show the numerical results of the topological solutions. We then calculate the changed characteristics of the electroweak monopole such as the monopole mass and the electromagnetic charges, as well as the axion potential energy.

    hep-phNPB(2026)·2 citations
12. 12*

    Temperature and volume dependence of pion-pion scattering lengths

    Qing-Wu Wang🇨🇳 · Hua-Zhong Guo🇨🇳

    The s-wave pion-pion scattering lengths $a_0$ and $a_2$ are studied at finite temperature and in finite spatial volume under the framework of the Nambu--Jona-Lasinio model. With the proper time regularization, the behavior beyond the pseudo transition temperature is presented. The scattering length $a_0$ shows singularity near the Mott temperature and $a_2$ is a continuous but non-monotonic function of temperature. We present the finite volume effect on the scattering length and have found that $a_0$ can be negative and its singularity disappears at small volume size which may hint the existence of chiral phase transition as volume decreases.

    hep-phCPC(2024)·1 citation
13. 13*

    Approximate N${}^5$LO Higgs boson decay width $\Gamma (H\to \gamma \gamma )$

    Yu-Feng Luo (Chongqing University)🇨🇳 · Jiang Yan (Chongqing University)🇨🇳 · Zhi-Fei Wu (Chongqing University)🇨🇳 · Xing-Gang Wu (Chongqing University)🇨🇳

    The precision and predictive power of perturbative QCD (pQCD) prediction depends on both a precise, convergent fixed-order series and a reliable way of estimating the contributions of unknown higher-order (UHO) terms. It has been shown that by applying the Principal of Maximum Conformality (PMC), which applies the renormalization group equation recursively to set the effective magnitude of ${\alpha }_s$ of the process, the remaining conformal coefficients will be well matched with the corresponding ${\alpha }_s$ at each orders, leading to a scheme-and-scale invariant and convergent perturbative series. Thus different from conventional scheme-and-scale dependent fixed-order series, the PMC series will provide a more reliable platform for estimating UHO contributions. In this paper, by using the total decay width $\Gamma (H\to \gamma \gamma )$ which has been calculated up to N${}^4$LO QCD corrections, we derive its PMC series by using the PMC single-scale setting approach and estimate its unknown N${}^5$LO contributions by using the Bayesian analysis. The Bayesian-based approach estimates the magnitude of the UHO contributions based on an optimized analysis of probability density distribution, and the predicted UHO contribution becomes more accurate when more loop terms have been known to tame the probability density function. Using the top-quark pole mass $M_t$=172.69 GeV and the Higgs mass $M_H$=125.25 GeV as inputs, we obtain $\Gamma (H\to \gamma \gamma )=9.56504\mathrm{keV}$ and the estimated N${}^5$LO contribution to the total decay width is $\Delta {\Gamma }_H=\pm 1.65\times 10^{-4}\mathrm{keV}$ for the smallest credible interval of $95.5\%$ degree-of-belief.

    hep-phSymmetry(2024)·6 citations
14. 14*

    Flavor invariance of leptonic Yukawa terms in the 3HDM

    Bartosz Dziewit🇵🇱 · Joris Vergeest🇵🇱 · Marek Zrałek🇵🇱

    As an extension of the Standard Model (SM), the 3HDM (Three-Higgs-Doublet Model) defines additional relationships among the fermions. In the visible leptonic Yukawa sector of the 3HDM, we investigate the existence of flavor symmetries under discrete non-abelian groups up to order 1032. When the VEVs are not allowed to depart from their alignment imposed by the condition of minimal potential in the Higgs scalar sector, there will be severe mass degeneracies and a lack of lepton flavor mixing for any nontrivial flavor group. Yet we propose to study the Yukawa terms of the lepton sector for in case the VEV alignment would not be protected, hence leaving the VEV ratios as free parameters. Then, as it turns out, mass splitting for the charged leptons and the neutrinos is obtained although it is still impossible to obtain correct fits to the experimentally known lepton mass spectrum and to the PMNS matrix simultaneously.

    hep-phPLB(2024)·3 citations
15. 15*

    Testing Gravity and Predictions Beyond the Standard Model at Short Distances: The Casimir Effect

    Galina L. Klimchitskaya🇷🇺 · Vladimir M. Mostepanenko🇷🇺

    The Standard Model of elementary particles and their interactions does not include the gravitational interaction and faces problems in understanding of the dark matter, dark energy, strong CP violation etc. In continuing attempts to solve these problems, many predictions of new light elementary particles and hypothetical interactions beyond the Standard Model have been made. These predictions can be constrained by many means and, specifically, by measuring the Casimir force arising between two closely spaced bodies due to the zero-point and thermal fluctuations of the electromagnetic field. After a brief survey in the theory of the Casimir effect, the strongest constraints on the power-type and Yukawa-type corrections to Newtonian gravity, following from measuring the Casimir force at short distances, are considered. Next,the problems of dark matter, dark energy and their probable constituents are discussed. This is followed by an analysis of constraints on the dark matter particles, and, specifically, on axions and axionlike particles, obtained from the Casimir effect. The question of whether the Casimir effect can be used for constraining the spin-dependent interactions is also considered. Then the constraints on the dark energy particles, like chameleons and symmetrons, are examined. In all cases the subject of our treatment is not only measurements of the Casimir force but some other relevant table-top experiments as well. In conclusion, the prospects of the Casimir effect for constraining theoretical predictions beyond the Standard Model at short distances are summarized.

    hep-phLect.Notes Phys.(2023)·5 citations
16. 16*

    Productions of $D_{s0}^{\ast }(2317)$ and $D_{s1}(2460)$ in $B_{(s)}$ and ${\Lambda }_b({\Xi }_b)$ decays

    Ming-Zhu Liu🇨🇳 · Xi-Zhe Ling🇨🇳 · Li-Sheng Geng🇨🇳

    Recent studies show that $D_{s0}^{\ast }(2317)$ and $D_{s1}(2460)$ contain large molecular components. In this work, we employ the naive factorization approach to calculate the production rates of $D_{s0}^{\ast }(2317)$ and $D_{s1}(2460)$ as hadronic molecules in $B_{(s)}$ and ${\Lambda }_b({\Xi }_b)$ decays, where their decay constants are estimated in the effective Lagrangian approach. With the so-obtained decay constants $f_{D_{s0}^{\ast }(2317)}$ and $f_{D_{s1}(2460)}$, we calculate the branching fractions of the $b$-meson decays $B_{(s)}\to {\bar{D}}_{(s)}^{(\ast )}{D}_{s0}^{\ast }$ and $B_{(s)}\to {\bar{D}}_{(s)}^{(\ast )}{D}_{s1}$ and the $b$-baryon decays ${\Lambda }_b({\Xi }_b)\to {\Lambda }_c({\Xi }_c)D_{s0}^{\ast }$ and ${\Lambda }_b({\Xi }_b)\to {\Lambda }_c({\Xi }_c)D_{s1}$. Our results show that the production rates of $D_{s0}^{\ast }(2317)$ and $D_{s1}(2460)$ in the $B_s$, ${\Lambda }_b$ and ${\Xi }_b$ decays are rather large that future experiments could observe them. In particular, we demonstrate that one can extract the decay constants of hadronic molecules via the triangle mechanism because of the equivalence of the triangle mechanism to the tree diagram established in calculating the decays $B\to {\bar{D}}^{(\ast )}{D}_{s0}^{\ast }(2317)$ and $B\to {\bar{D}}^{(\ast )}{D}_{s1}(2460)$.

    hep-phPRD(2024)·13 citations
17. 17*

    Differential $e\mu bb$ Cross-Sections and New Higgses at the Electroweak Scale

    Sumit Banik🇨🇭 · Guglielmo Coloretti🇨🇭 · Andreas Crivellin🇨🇭 · Bruce Mellado🇿🇦

    ATLAS found that none of their Standard Model simulations can describe the measured differential lepton distributions in their $t\bar{t}$ analysis reasonably well. Therefore, we study the possibility that this measurement has a new physics contamination. We consider a benchmark model motivated by the indications for di-photon resonances: A heavy scalar decays into two lighter Higgs bosons with masses of 152\,GeV and 95\,GeV, with subsequent decay to $WW$ and $bb$, respectively. In this setup, the description of data is improved by at least $5.6\sigma$.

    hep-ph1 citation
18. 18*

    ee$\in$MC: Low Energy Mesons and the Residual QCD Potential

    Ian M. Nugent🇨🇦

    The Flux-Tube Breaking Model in ee$\in$MC is expanded to include the residual QCD potential between the Final-State mesons, within the non-relativistic limit. These residual QCD potentials have been predicted in the context of the Flux-Tube Breaking Models to generate meson-meson molecular states for the $f_0(500)$, $f_0(980)$, $a_0(980)$, through the colour hyper-fine spin-spin interaction. These residual potentials are also found to have an important impact on the $S_1$ decay of the $a_1$ and $K_1$ axial-vector mesons due to the colour hyper-fine spin-spin interaction. It is found that in the low mass regions, the $\rho (770)$ and $K^{\ast }(892)$ are sensitive to the linear-confining potential and colour-Coulomb potential suggesting that with the high statistics at the B-Factories, it may be possible to probe the linear-confining potential and colour-Coulomb potential through a model dependent description of the resonance shape or by exploiting multiple production process.

    hep-phhep-ex1 citation
19. 19*

    Flavor asymmetry of light sea quarks in proton : A light-front spectator model

    Poonam Choudhary🇮🇳 · Dipankar Chakrabarti🇮🇳 · Chandan Mondal🇨🇳

    We formulate a light-front spectator model for the proton that incorporates the presence of light sea quarks. In this particular model, the sea quarks are seen as active partons, whereas the remaining components of the proton are treated as spectators. The proposed model relies on the formulation of the light-front wave function constructed by the soft wall AdS/QCD. The model wave functions are parameterized by fitting the unpolarized parton distribution functions of light sea quarks from the CTEQ18 global analysis. We then employ the light-front wave functions to obtain the sea quarks generalized parton distribution functions, transverse momentum dependent parton distributions, and their asymmetries, which are accessible in the upcoming Electron-Ion-Colliders. We investigate sea quarks' spin and orbital angular momentum contributions to the proton spin.

    hep-phEPJC(2024)·7 citations
20. 20*

    $Z_3$ symmetry of the CKM and PMNS matrices

    Piotr Kielanowski🇲🇽 · S. Rebeca Juárez Wysozka🇲🇽 · Liliana Vázquez Mercado🇲🇽

    We develop for the CKM and PMNS matrices a new representation with special properties. It is obtained by splitting each of these matrices into two rotations by the angle $\sim 2\pi /3$ and a universal diagonal matrix with elements, which are cubic roots of~1. Such a representation of the CKM and PMNS matrices may indicate the $Z_3$ symmetry to be present in the Yukawa sector of the~SM. Identical mathematical structure of the CKM and PMNS matrices is also an extension of the quark-lepton universality. In this approach the CP violation is a natural consequence of the structure of the Yukawa couplings. The CP violating phase is not a fitted parameter and its value is governed by the parameters of two rotations. The parameters of the diagonalizing matrices of the bi-unitary transformation do not exhibit a hierarchy, which means that the origins of the hierarchy of quark masses and of the CKM matrix elements are not the same.

    hep-phhep-ex1 citation
21. 21*

    Impact of the LZ Experiment on the DM Phenomenology and Naturalness in the MSSM

    Li Dongwei🇨🇳 · Meng Lei🇨🇳 · Zhou Haijing🇨🇳

    This paper uses approximate analytical formulas and numerical results with the bino-dominated dark matter (DM) as an example to analyze the impact of the LUX-ZEPLIN (LZ) experiment on the DM phenomenology and naturalness in the Minimal Supersymmetric Standard Model (MSSM). We conclude that the limitation of the latest LZ experiment worsens the naturalness of the MSSM, as the predictions of the $Z$-boson mass and DM relic density demonstrate, particularly in the regions where the correct DM relic density is obtained by the $Z$- or $h$-mediated resonant annihilations.

    hep-phNPB(2024)·2 citations
22. 22*

    Simple Lévy-$\alpha$ stable model analysis of elastic $pp$ and $p\bar{p}$ low-$|t|$ data from SPS to LHC energies

    T. Csörgő🇭🇺 · S. Hegyi🇭🇺 · I. Szanyi🇭🇺

    A simple Lévy-$\alpha$ stable (SL) model is used to describe the data on elastic $pp$ and $p\bar{p}$ scattering at low-$|t|$ from SPS energies up to LHC energies. The SL model is demonstrated to describe the data with a strong non-exponential feature in a statistically acceptable manner. The energy dependence of the parameters of the model is determined and analyzed. The Lévy $\alpha$ parameter of the model has an energy-independent value of 1.959 $\pm$ 0.002 following from the strong non-exponential behavior of the data. We strengthen the conclusion that the discrepancy between TOTEM and ATLAS elastic $pp$ differential cross section measurements arises only in the normalization and not in the shape of the distribution of the data as a function of $t$. We find that the slope parameter has different values for $pp$ and $p\bar{p}$ elastic scattering at LHC energies. This may be the effect of the odderon exchange or the jump in the energy dependence of the slope parameter in the energy interval 3 GeV $\lesssim \sqrt{s}\lesssim$ 4 GeV.

    hep-phUniverse(2024)·2 citations
23. 23*

    Allowed region for the (second) lightest mass $M_{1,2}$ of right-handed neutrino ${\nu }_{R1,2}$ with $SO(10)$-inspired relations and sequential dominance

    Masaki J. S. Yang🇯🇵

    In this paper, we evaluate the (second) lightest mass $M_{1,2}$ of right-handed neutrino ${\nu }_{R1,2}$ in grand unified theories with the type-I seesaw mechanism that predicts an almost massless neutrino $m_{1\mathrm{or}3}\sim 0$. By chiral perturbative treatment, the masses $M_{1,2}$ are expressed as $M_1=m_{D1}^2/m_{11},M_2=m_{D2}^2{m}_{11}/(m_{11}{m}_{22}-m_{12}^2)$ with the mass matrix of left-handed neutrinos $m$ in the diagonal basis of the Dirac mass matrix $m_D$. Assuming $m_{Di}$ and the unitary matrix $V$ in the singular value decomposition $(m_D{)}_{ij}=V_{ik}{m}_{Dk}{U}_{kj}^{†}$ are close to observed fermion masses and the CKM matrix, $M_{1,2}$ and their allowed regions are expressed by parameters in the low energy and unknown phases. As a result, for $m_{D1}\simeq 0.5$ MeV and $m_{D2}\simeq 100$ MeV, we obtain $M_1^{\mathrm{NH}}\simeq 3\times 10^{4-6}$ GeV and $M_2^{\mathrm{NH}}\simeq 3\times 10^{6-8}$ GeV in the NH, $M_1^{\mathrm{IH}}\simeq 5\times 10^{3-4}$ GeV and $M_2^{\mathrm{IH}}\simeq 4\times 10^{8-9}$ GeV in the IH. These upper and lower bounds are proportional to $m_{Di}^2$ or $m_{D1}{m}_{D2}$.

    hep-ph1 citation
24. 24*

    Test of vector portal with dark fermions in the charge-exchange reactions in the NA64 experiment at CERN SPS

    Sergei N. Gninenko🇷🇺 · Dmitry V. Kirpichnikov🇷🇺 · Sergey Kuleshov🇨🇱 · Valery E. Lyubovitskij🇨🇱 · Alexey S. Zhevlakov🇷🇺

    We consider an experiment to search for dark sector particles in dark photon kinetic mixing model by analyze invisible and semi-invisible decays of neutral mesons $M^0={\pi }^0$, $\eta$, ${\eta }^{\prime }$, $\omega$, $f_2(1270)$, produced in the NA64 experiment at the CERN SPS. The approach proposed in Ref.~\cite{Gninenko:2014sxa} is to use the charge-exchange reactions ${\pi }^{-}+(A,Z)\to M^0+(A,Z-1);M^0\to$ invisible or semi-invisible of high-energy pions (or kaons) at a nuclei target as a source of $M^0$s, which subsequently decay invisibly into dark sector. This reaction chain would lead to a striking signature of the signal event - the complete disappearance of the beam energy in the setup. Using data obtained from the study of charge-exchange reactions at IHEP (Protvino) and Fermilab (Batavia) we show that the integral cross sections $\sigma$ for production of the neutral mesons $M^0$ are slightly deviate from phenomenological formula $\sigma \sim Z^{2/3}$, where $Z$ is the nuclei charge. In particular, we present the formulas for the differential and integral sections that explicitly depend on the Mandelstam and $Z$ variables. Derived formulas are used to predict the cross sections as a function of beam energy for several target nuclei, and to estimate the projection sensitivity for the proposed search for the $M^0\to$ semi-invisible and $M^0\to$ invisible decays through the vector portal to dark sector. Sensitivity to different semi-invisible decay modes of neutral pseudoscalar mesons is studied.

    hep-phPRD(2024)·16 citations
25. 25*

    Type-II Seesaw Leptogenesis along the Ridge

    Chengcheng Han🇨🇳 · Zhanhong Lei🇨🇳 · Jin Min Yang🇨🇳

    Type-II seesaw leptogenesis is a model that integrates inflation, baryon number asymmetry, and neutrino mass simultaneously. It employs the Affleck-Dine mechanism to generate lepton asymmetry, with the Higgs bosons serving as the inflaton. Previous studies assumed inflation to occur in a valley of the potential, employing the single-field approximation. In this work, we explore an alternative scenario for the type-II seesaw leptogenesis, where the inflation takes place along a ridge of the potential. Firstly, we conduct a comprehensive numerical calculation in the canonical scenario, where inflation occurs in a valley, confirming the effectiveness of the single-field approximation. Then, we introduce a novel scenario wherein inflation initiates along the potential's ridge and transitions to the valley in the late stages. In this case, the single-field inflation approximation is no longer valid, yet leptogenesis is still successfully achieved. We find that this scenario can generate a significant non-Gaussianity signature, offering testable predictions for future experiments.

    hep-phastro-ph.COhep-thPhys.Dark Univ.(2025)·3 citations
26. 26*

    $J/\psi$ polarization in relativistic heavy ion collisions

    Jiaxing Zhao🇫🇷 · Baoyi Chen🇨🇳

    Understanding the polarization property of $J/\psi$ is critical to constrain its production mechanism. In addition, the polarization of $J/\psi$ can reveal the impact of strong electromagnetic and vorticity fields in relativistic heavy ion collisions. In this study, we analyzed the yield and polarization of $J/\psi$ in relativistic heavy ion collisions at different centrality and transverse momentum regions, using three different reference frames: the Collins-Soper frame, the helicity frame, and the event plane frame. The polarization of initially produced $J/\psi$ is determined by the NRQCD calculation and is similar to that of $pp$ collisions. However, both unpolarization and transverse polarization are considered for the regenerated $J/\psi$. Our results indicate that the polarization at high $p_T$ is similar to that observed in $pp$ collisions. However, at low $p_T$, where regenerated $J/\psi$ dominates, it is likely that the polarized charm quarks in the rotational QGP medium are responsible for this phenomenon. Our study supplies a baseline for future research on the effects of strong electromagnetic and vorticity fields on $J/\psi$ polarization.

    hep-phnucl-thEPJC(2024)·8 citations
27. 27*

    Triply heavy tetraquark states: masses and other properties

    Zhen-Hui Zhu🇨🇳 · Wen-Xuan Zhang🇨🇳 · Duojie Jia🇨🇳

    In this work, we study masses and other static properties of triply heavy tetraquarks in the unified framework of the MIT bag which incorporates chromomagnetic interactions and enhanced binding energy. The masses, magnetic moments and charge radii of all strange and nonstrange (ground) states of triply heavy tetraquarks are computed, suggesting that all of triply heavy tetraquarks are above the respective two-meson thresholds. We also estimate relative decay widths of main decay channels of two-heavy mesons for these tetraquarks.

    hep-phEPJC(2024)·16 citations
28. 28*

    Strange hidden-charm pentaquark poles from $B^{-}\to J/\psi \Lambda \bar{p}$

    Satoshi X. Nakamura (Shandong Univ.)🇨🇳 · Jia-Jun Wu (Univ. of Chinese Academy of Sciences)🇨🇳

    Recent LHCb data for $B^{-}\to J/\psi \Lambda \bar{p}$ show a clear peak structure at the ${\Xi }_c\bar{D}$ threshold in the $J/\psi \Lambda$ invariant mass ($M_{J/\psi \Lambda }$) distribution. The LHCb's amplitude analysis identified the peak with the first hidden-charm pentaquark with strangeness $P_{\psi s}^{\Lambda }(4338)$. We conduct a coupled-channel amplitude analysis of the LHCb data by simultaneously fitting the $M_{J/\psi \Lambda }$, $M_{J/\psi \bar{p}}$, $M_{\Lambda \bar{p}}$, and $\cos {\theta }_{K^{\ast }}$ distributions. Rather than the Breit-Wigner fit employed in the LHCb analysis, we consider relevant threshold effects and a unitary ${\Xi }_c\bar{D}$-${\Lambda }_c{\bar{D}}_s$ coupled-channel scattering amplitude from which $P_{\psi s}^{\Lambda }$ poles are extracted for the first time. In our default fit, the $P_{\psi s}^{\Lambda }(4338)$ pole is almost a ${\Xi }_c\bar{D}$ bound state at $(4338.2\pm 1.4)-(1.9\pm 0.5)i$ MeV. Our default model also fits a large fluctuation at the ${\Lambda }_c{\bar{D}}_s$ threshold, giving a ${\Lambda }_c{\bar{D}}_s$ virtual state, $P_{\psi s}^{\Lambda }(4255)$, at $4254.7\pm 0.4$ MeV. We also found that the $P_{\psi s}^{\Lambda }(4338)$ peak cannot solely be a kinematical effect, and a nearby pole is needed.

    hep-phhep-exnucl-thEPJ Web Conf.(2024)·1 citation
29. 29*

    Parameter optimisation using Bayesian inference for spallation models

    Jason Hirtz🇫🇷 · Jean-Christophe David🇫🇷 · Joseph Cugnon🇧🇪 · Ingo Leya🇨🇭 · José Luís Rodríguez-Sánchez🇪🇸 · Georg Schnabel🇦🇹

    The accuracy and precision of high-energy spallation models are key issues for the design and development of new applications and experiments. We present a method to estimate model parameters and associated uncertainties by leveraging the Bayesian version of the Generalised Least Squares method, which enables us to incorporate prior knowledge on the parameter values. This approach is designed to adjust parameters based on experimental data, accounting for experimental uncertainty information, and providing uncertainties for all adjusted parameters. This approach is designed in order both to improve the accuracy of models through the modification of free parameters of these models, which results in a better reproduction of experimental data, and to estimate the uncertainties of these parameters and, by extension, their impacts on the model output. We aim at demonstrating the Generalised Least Square method can be applied in the case of Monte Carlo models. We present a proof-of-concept for Monte Carlo models in the specific case of nuclear physics with the model combination INCL/ABLA. We discuss the challenges in the application of this method to high-energy spallation models, notably the large runtime and the stochasticity of the models. Our results indicate this framework can also be applied to analogous situations where parameters of a computationally expensive Monte Carlo code should be inferred/improved.

    hep-phnucl-thEPJA(2024)·4 citations
30. 30*

    Remote sensing of backward reflection from stimulated axion decay

    Kensuke Homma🇯🇵

    We propose a method for remotely detecting backward reflection via induced decay of cold dark matter such as axion in the background of a propagating coherent photon field. This method can be particularly useful for probing concentrated dark matter streams by Earth's gravitational lensing effect. Formulae for the stimulated reflection process and the expected sensitivities in local and remote experimental approaches are provided for testing eV scale axion models using broad band lasers. The generic axion-photon coupling is expected to be explorable up to $\mathcal{O}(10^{-12})$ GeV${}^{-1}$ and $\mathcal{O}(10^{-22})$ GeV${}^{-1}$ for the idealized local and remote setups, respectively.

    hep-phJHEP(2024)·2 citations
31. 31*

    Far-from-equilibrium attractors for massive kinetic theory in the relaxation time approximation

    Huda Alalawi🇺🇸 · Michael Strickland🇺🇸

    In this proceedings contribution, we summarize recent findings concerning the presence of early- and late-time attractors in non-conformal kinetic theory. We study the effects of varying both the initial momentum-space anisotropy and initialization times using an exact solution of the 0+1D boost-invariant Boltzmann equation with a mass- and temperature-dependent relaxation time. Our findings support the existence of a longitudinal pressure attractor, but they do not support the existence of distinct attractors for the bulk viscous and shear pressures. Considering a large set of integral moments, we show that for moments with greater than one power of longitudinal momentum squared, both early- and late-time attractors are present.

    hep-phnucl-thEPJ Web Conf.(2024)·0 citations
32. 32*

    Tensions in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}(\gamma )$ measurements: the new landscape of data-driven hadronic vacuum polarization predictions for the muon $g-2$

    M. Davier🇫🇷 · A. Hoecker🇨🇭 · A.M. Lutz🇫🇷 · B. Malaescu🇫🇷 · Z. Zhang🇫🇷

    The situation of the experimental data used in the dispersive evaluation of the hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon is assessed in view of two recent measurements: $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ cross sections in the $\rho$ resonance region by CMD-3 and a study of higher-order radiative effects in the initial-state-radiation processes $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}\gamma$ and $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\gamma$ by BABAR. The impact of the latter study on the KLOE and BESIII cross-section measurements is evaluated and found to be indicative of larger systematic effects than uncertainties assigned. The new situation also warrants a reappraisal of the independent information provided by hadronic $\tau$ decays, including state-of-the-art isospin-breaking corrections. The findings cast a new light on the longstanding deviation between the muon $g-2$ measurement and the Standard Model prediction using the data-driven dispersive approach, and the comparison with lattice QCD calculations.

    hep-phhep-exEPJC(2024)·95 citations
33. 33*

    Learning Feynman integrals from differential equations with neural networks

    Francesco Calisto🇩🇪 · Ryan Moodie🇮🇹 · Simone Zoia🇨🇭

    We perform an exploratory study of a new approach for evaluating Feynman integrals numerically. We apply the recently-proposed framework of physics-informed deep learning to train neural networks to approximate the solution to the differential equations satisfied by the Feynman integrals. This approach relies neither on a canonical form of the differential equations, which is often a bottleneck for the analytical techniques, nor on the availability of a large dataset, and after training yields essentially instantaneous evaluation times. We provide a proof-of-concept implementation within the PyTorch framework, and apply it to a number of one- and two-loop examples, achieving a mean magnitude of relative difference of around 1% at two loops in the physical phase space with network training times on the order of an hour on a laptop GPU.

    hep-phhep-thJHEP(2024)·13 citations
34. 34*

    Ruling out models of vector dark matter in asymptotically safe quantum gravity

    Gustavo P. de Brito🇩🇰 · Astrid Eichhorn🇩🇰 · Mads T. Frandsen🇩🇰 · Martin Rosenlyst🇬🇧 · Mattias E. Thing🇩🇰 · Arthur F. Vieira🇩🇰

    The nature of dark matter is a problem with too many potential solutions. We investigate whether a consistent embedding into quantum gravity can decimate the number of solutions to the dark-matter problem. Concretely, we focus on a hidden sector composed of a gauge field and a charged scalar, with gauge group U(1)${}_{\text{D}}$ or SU(2)${}_{\text{D}}$. The gauge field is the dark matter candidate, if the gauge symmetry is broken spontaneously. Phenomenological constraints on the couplings in this model arise from requiring that the correct dark matter relic density is produced via thermal freeze-out and that recent bounds from direct-detection experiments are respected. We find that the consistent embedding into asymptotically safe quantum gravity gives rise to additional constraints on the couplings at the Planck scale, from which we calculate corresponding constraints at low energy scales. We discover that phenomenological constraints cannot be satisfied simultaneously with theoretical constraints from asymptotically safe quantum gravity, ruling out these dark matter models.

    hep-phgr-qchep-thPRD(2024)·13 citations
35. 35*

    Quantum State-Channel Duality for the calculation of Standard Model scattering amplitudes

    Clelia Altomonte🇬🇧 · Alan J. Barr🇬🇧

    Recent instances of successful application of quantum information techniques to particle physics problems invite for an analysis of the mathematical details behind such connection. In this paper, we identify the Choi-Jamiolkowski isomorphism, or state-channel duality, as a theoretical principle enabling the application of the theory of quantum information to the scattering amplitudes associated with Standard Model processes.

    hep-phPLB(2023)·15 citations
36. 36*

    Scaling Laws in Jet Classification

    Joshua Batson🇺🇸 · Yonatan Kahn🇺🇸

    We demonstrate the emergence of scaling laws in the benchmark top versus QCD jet classification problem in collider physics. Six distinct physically-motivated classifiers exhibit power-law scaling of the binary cross-entropy test loss as a function of training set size, with distinct power law indices. This result highlights the importance of comparing classifiers as a function of dataset size rather than for a fixed training set, as the optimal classifier may change considerably as the dataset is scaled up. We speculate on the interpretation of our results in terms of previous models of scaling laws observed in natural language and image datasets.

    hep-phcs.LGSciPost Phys.Core(2025)·19 citations
37. 37*

    Study of a cubic cavity resonator for gravitational waves detection in the microwave frequency range

    Pablo Navarro🇪🇸 · Benito Gimeno🇪🇸 · Juan Monzó-Cabrera🇪🇸 · Alejandro Díaz-Morcillo🇪🇸 · Diego Blas🇪🇸

    The direct detection of gravitational waves (GWs) of frequencies above MHz has recently received considerable attention. In this work we present a precise study of the reach of a cubic cavity resonator to GWs in the microwave range, using for the first time tools allowing to perform realistic simulations. Concretely, the BI-RME 3D method, which allows us to obtain not only the detected power but also the detected voltage (magnitude and phase), is used here. After analyzing three cubic cavities for different frequencies and working simultaneously with three different degenerate modes at each cavity, we conclude that the sensitivity of the experiment is strongly dependent on the polarization and incidence angle of the GW. The presented experiment can reach sensitivities up to $1\cdot 10^{-19}$ at 100\, MHz, $2\cdot 10^{-20}$ at 1\, GHz, and $6\cdot 10^{-19}$ at 10\, GHz for optimal angles and polarizations, and where in all cases we assumed an integration time of $\Delta t=1$ ms. These results provide a strong case for further developing the use of cavities to detect GWs. Moreover, the possibility of analyzing the detected voltage (magnitude and phase) opens a new interferometric detection scheme based on the combination of the detected signals from multiple cavities.

    hep-phgr-qchep-exphysics.ins-detPRD(2024)·23 citations
38. 38*

    Learning PDFs through Interpretable Latent Representations in Mellin Space

    Brandon Kriesten🇺🇸 · T. J. Hobbs🇺🇸

    Representing the parton distribution functions (PDFs) of the proton and other hadrons through flexible, high-fidelity parametrizations has been a long-standing goal of particle physics phenomenology. This is particularly true since the chosen parametrization methodology can play an influential role in the ultimate PDF uncertainties as extracted in QCD global analyses; these, in turn, are often determinative of the reach of experiments at the LHC and other facilities to non-standard physics, including at large $x$, where parametrization effects can be significant. In this study, we explore a series of encoder-decoder machine-learning (ML) models with various neural-network topologies as efficient means of reconstructing PDFs from meaningful information stored in an interpretable latent space. Given recent effort to pioneer synergies between QCD analyses and lattice-gauge calculations, we formulate a latent representation based on the behavior of PDFs in Mellin space, i.e., their integrated moments, and test the ability of various models to decode PDFs from this information faithfully. We introduce a numerical package, $\text{PDFdecoder}$, which implements several encoder-decoder models to reconstruct PDFs with high fidelity and use this tool to explore strengths and pitfalls of neural-network approaches to PDF parametrization. We additionally dissect patterns of learned correlations between encoded Mellin moments and reconstructed PDFs which suggest opportunities for further improvements to ML-based approaches to PDF parametrizations and uncertainty quantification.

    hep-phhep-latnucl-thPRD(2025)·14 citations
39. 39*

    Observational Constraints on Extended Starobinsky and Weyl Gravity Model of Inflation

    Piyabut Burikham🇹🇭 · Teeraparb Chantavat · Pongsapat Boonaom

    We present constraints on the extended Starobinsky and Weyl gravity model of inflation using updated available observational data. The data includes cosmic microwave background (CMB) anisotropy measurements from Planck and BICEP/Keck 2018 (BK18), as well as large-scale structure data encompassing cosmic shear and galaxy autocorrelation and cross-correlation functions measurements from Dark Energy Survey (DES), baryonic acoustic oscillation (BAO) measurements from 6dF, MGS and BOSS, and distance measurements from supernovae type Ia from Pantheon+ samples. By introducing a single additional parameter, each model extends the Starobinsky model to encompass larger region of parameter space while remaining consistent with all observational data. Our findings demonstrate that the inclusion of higher-order terms loosen the constraint on the upper bound of $e$-folding number $N_{\mathrm{e}}$ due to the presence of small additional parameter. The maximum limit on $N_{\mathrm{e}}$ could be refined by considering the reheating process to $N_{\mathrm{e}}<55-59$ for $k_{\ast }=0.002,0.05$ Mpc${}^{-1}$. These models extend viable range of tensor-to-scalar ratio~($r$) to very small value $r<0.002$ in contrast to the original $R^2$ Starobinsky model. In addition, our results continue to emphasize the tension in $H_0$ and $S_8$ between early-time CMB measurements and late-time large-scale structure observations.

    ↳ astro-ph.COhep-phJHEAp(2024)·4 citations
40. 40*

    CosmiXs: Cosmic messenger spectra for indirect dark matter searches

    Chiara Arina🇧🇪 · Mattia Di Mauro🇮🇹 · Nicolao Fornengo🇮🇹 · Jan Heisig🇩🇪 · Adil Jueid🇰🇷 · Roberto Ruiz de Austri🇪🇸

    The energy spectra of particles produced from dark matter (DM) annihilation or decay are one of the fundamental ingredients to calculate the predicted fluxes of cosmic rays and radiation searched for in indirect DM detection. We revisit the calculation of the source spectra for annihilating and decaying DM using the Vincia shower algorithm in Pythia to include QED and QCD final state radiation and diagrams for the Electroweak (EW) corrections with massive bosons, not present in the default Pythia shower model. We take into account the spin information of the particles during the entire EW shower and the off-shell contributions from massive gauge bosons. Furthermore, we perform a dedicated tuning of the Vincia and Pythia parameters to LEP data on the production of pions, photons, and hyperons at the $Z$ resonance and discuss the underlying uncertainties. To enable the use of our results in DM studies, we provide the tabulated source spectra for the most relevant cosmic messenger particles, namely antiprotons, positrons, $\gamma$ rays and the three neutrino flavors, for all the fermionic and bosonic channels and DM masses between 5 GeV and 100 TeV, on https://github.com/ajueid/CosmiXs.git.

    ↳ astro-ph.HEhep-phJCAP(2024)·45 citations
41. 41*

    Topological defect formation in a phase transition with tunable order

    Fumika Suzuki🇺🇸 · Wojciech H. Zurek🇺🇸

    The Kibble-Zurek mechanism (KZM) describes the non-equilibrium dynamics and topological defect formation in systems undergoing second-order phase transitions. KZM has found applications in fields such as cosmology and condensed matter physics. However, it is generally not suitable for describing first-order phase transitions. It has been demonstrated that transitions in systems like superconductors or charged superfluids, typically classified as second-order, can exhibit weakly first-order characteristics when the influence of fluctuations is taken into account. Moreover, the order of the phase transition (i.e., the extent to which it becomes first rather than second order) can be tuned. We explore quench-induced formation of topological defects in such tunable phase transitions and propose that their density can be predicted by combining KZM with nucleation theory.

    ↳ cond-mat.stat-mechgr-qchep-phhep-th+1PRL(2024)·25 citations
42. 42*

    Hyperpolyadic structures

    Steven Duplij (University of Münster)🇩🇪

    We introduce a new class of division algebras, the hyperpolyadic algebras, which correspond to the binary division algebras $\mathbb{R}$, $\mathbb{C}$, $\mathbb{H}$, $\mathbb{O}$ without considering new elements. First, we use the matrix polyadization procedure proposed earlier which increases the dimension of the algebra. The algebras obtained in this way obey binary addition and a nonderived n-ary multiplication and their subalgebras are division n-ary algebras. For each invertible element we define a new norm which is polyadically multiplicative, and the corresponding map is a $n$-ary homomorphism. We define a polyadic analog of the Cayley-Dickson construction which corresponds to the consequent embedding of monomial matrices from the polyadization procedure. We then obtain another series of n-ary algebras corresponding to the binary division algebras which have a higher dimension, that is proportional to the intermediate arities. Second, a new polyadic product of vectors in any vector space is defined. Endowed with this product the vector space becomes a polyadic algebra which is a division algebra under some invertibility conditions, and its structure constants are computed. Third, we propose a new iterative process ("imaginary tower"), which leads to nonunital nonderived ternary division algebras of half the dimension, which we call "half-quaternions" and "half-octonions". The latter are not subalgebras of the binary division algebras, but subsets only, since they have different arity. Nevertheless, they are actually ternary division algebras, because they allow division, and their nonzero elements are invertible. From the multiplicativity of the introduced "half-quaternion" norm we obtain the ternary analog of the sum of two squares identity. We show that the ternary division algebra of imaginary "half-octonions" is unitless and totally associative.

    ↳ math.RAhep-phhep-thmath.NT+1Mathematics(2024)·0 citations
43. 43*

    Strangeness production in double gap events in ALICE

    R.Schicker (on behalf of the ALICE collaboration)🇩🇪

    The ALICE detector at the LHC was upgraded in the long shutdown of 2019-2021 in order to take data at much-increased Run 3 and 4 rates. The various challenges of this upgrade are presented, and the first results of strangeness production in double gap events collected in 2022 are shown by presenting distributions of kaon pairs.

    ↳ hep-exhep-ph0 citations
44. 44*

    NANOGrav hints for first-order confinement-deconfinement phase transition in different QCD-matter scenarios

    Zu-Cheng Chen🇨🇳 · Shou-Long Li🇨🇳 · Puxun Wu🇨🇳 · Hongwei Yu🇨🇳

    Recent observations from several pulsar timing array (PTA) collaborations have unveiled compelling evidence for a stochastic signal in the nanohertz band. This signal aligns remarkably with a gravitational wave (GW) background, potentially originating from the first-order color charge confinement phase transition. Distinct quantum chromodynamics (QCD) matters, such as quarks or gluons, and diverse phase transition processes thereof can yield disparate GW energy density spectra. In this paper, employing the Bayesian analysis on the NANOGrav 15-year data set, we explore the compatibility with the observed PTA signal of the GW from phase transitions of various QCD matter scenarios in the framework of the holographic QCD. We find that the PTA signal can be effectively explained by the GW from the confinement-deconfinement phase transition of pure quark systems in a hard wall model of the holographic QCD where the bubble dynamics, one important source of the GWs, is of the Jouguet detonations. Notably, our analysis decisively rules out the plausibility of the pure gluon QCD-matter scenario and the non-runaway bubble dynamics model for the phase transition in explaining the observed PTA signal.

    ↳ astro-ph.COgr-qchep-phPRD(2024)·43 citations
45. 45*

    Solving the left-hand cut problem in lattice QCD: $T_{cc}(3875{)}^{+}$ from finite volume energy levels

    Lu Meng🇩🇪 · Vadim Baru🇩🇪 · Evgeny Epelbaum🇩🇪 · Arseniy A. Filin🇩🇪 · Ashot M. Gasparyan🇩🇪

    We discuss a novel effective-field-theory-based approach for extracting two-body scattering information from finite volume energies, serving as an alternative to Lüscher's method. By explicitly incorporating one-pion exchange, we overcome the challenging left-hand cut problem in Lüscher's method and can handle finite volume energy levels both below and above the left-hand cut. Applied to the lattice data for $D{D}^{\ast }$ scattering at a pion mass of 280 MeV, as an illustrative example, our results reveal the significant impact of the one-pion exchange on P-wave and S-wave phase shifts. The pole position of the $T_{cc}(3875{)}^{+}$ state, extracted from the finite-volume energy levels at this pion mass while taking into account left-hand cut effects, range corrections and partial-wave mixing, is consistent with a near-threshold resonance. This study demonstrates, for the first time, that two-body scattering information can be reliably extracted from lattice spectra including the left-hand cut.

    ↳ hep-lathep-phnucl-thPRD(2024)·78 citations
46. 46*

    Thermal twin stars within a hybrid equation of state based on a nonlocal chiral quark model compatible with modern astrophysical observations

    J.P. Carlomagno🇦🇷 · G.A. Contrera🇦🇷 · A.G. Grunfeld🇦🇷 · D. Blaschke🇵🇱

    We investigate the extension to finite temperatures and neutrino chemical potentials of a recently developed nonlocal chiral quark model approach to the equation of state of neutron star matter. We consider two light quark flavors and current-current interactions in the scalar-pseudoscalar, vector, and diquark pairing channels, where the nonlocality of the currents is taken into account by a Gaussian form factor that depends on the spatial components of the 4-momentum. Within this framework, we analyze order parameters, critical temperatures, phase diagrams, equations of state, and mass-radius relations for different temperatures and neutrino chemical potentials. For parameters of the model that are constrained by recent multi-messenger observations of neutron stars, we find that the mass-radius diagram for isothermal hybrid star sequences exhibits the thermal twin phenomenon for temperatures above 30 MeV.

    ↳ nucl-thastro-ph.HEhep-phPRD(2024)·21 citations
47. 47*

    Aether-Electromagnetic theory and the Casimir effect

    K. E. L. de Farias🇧🇷 · M. A. Anacleto🇧🇷 · E. Passos🇧🇷 · Iver Brevik🇳🇴 · Herondy Mota🇧🇷 · João R. L. Santos🇧🇷

    In this study, we explore the impact of an additional dimension, as proposed in Kaluza-Klein's theory, on the Casimir effect within the context of Lorentz invariance violation (LIV), which is represented by the ``aether field''. We demonstrate that the Casimir energy is directly influenced by the presence of the fifth dimension, as well as by the aether parameter. Consequently, the force between the plates is also subject to variations of these parameters. Furthermore, we examine constraints on both the size of the extra dimension and the aether field parameter based on experimental data. The LIV parameter can provide insights into addressing the size-related challenges in Kaluza-Klein's theory and offers a mean to establish an upper limit on the size of the extra dimension. This helps to rationalize the difficulties associated with its detection in current experiments.

    ↳ hep-thhep-phPRD(2024)·8 citations
48. 48*

    Fundamental Physics Opportunities with the Next-Generation Event Horizon Telescope

    Dimitry Ayzenberg🇩🇪 · Lindy Blackburn🇺🇸 · Richard Brito🇵🇹 · Silke Britzen🇩🇪 · Avery E. Broderick🇨🇦 · Raúl Carballo-Rubio🇩🇰 · Vitor Cardoso🇩🇰 · Andrew Chael🇺🇸 · Koushik Chatterjee🇺🇸 · Yifan Chen🇩🇰 · Pedro V. P. Cunha🇵🇹 · Hooman Davoudiasl🇺🇸 and 36 other authors

    The Event Horizon Telescope (EHT) Collaboration recently published the first images of the supermassive black holes in the cores of the Messier 87 and Milky Way galaxies. These observations have provided a new means to study supermassive black holes and probe physical processes occurring in the strong-field regime. We review the prospects of future observations and theoretical studies of supermassive black hole systems with the next-generation Event Horizon Telescope (ngEHT), which will greatly enhance the capabilities of the existing EHT array. These enhancements will open up several previously inaccessible avenues of investigation, thereby providing important new insights into the properties of supermassive black holes and their environments. This review describes the current state of knowledge for five key science cases, summarising the unique challenges and opportunities for fundamental physics investigations that the ngEHT will enable.

    ↳ astro-ph.HEastro-ph.IMgr-qchep-ph+1Living Rev.Rel.(2025)·131 citations
49. 49*

    Interplay of baryonic chiral partners in fluctuations of net-baryon number density

    Michał Marczenko🇵🇱 · Volker Koch🇺🇸 · Krzysztof Redlich🇵🇱 · Chihiro Sasaki🇵🇱

    In this contribution, we use the parity doublet model to investigate the fluctuations of the net-baryon number density. We discuss the systematics of the susceptibilities and their ratios for nucleons of positive and negative parity, as well as their correlator. We demonstrate that the fluctuations of positive-parity nucleon do not reflect the fluctuations of the total net-baryon number at the chiral phase transition.

    ↳ nucl-thhep-phEPJ Web Conf.(2024)·0 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.