Thu·Jan 11, 2024Thursday·January 11, 2024

1. 01*

   Electromagnetic properties of vector doubly charmed tetraquark states

   U. Özdem🇹🇷 · K. Azizi🇮🇷

   We conduct a systematic study of the electromagnetic properties of multiquark systems with undetermined internal structures. Motivated by the recent observation of the $T_{cc}^{+}$ state, we apply the light-cone version of the QCD sum rule method to extract the magnetic dipole moments of several possible doubly-charmed vector tetraquark states. When analyzing the magnetic dipole moment of these states, they are modeled to have the diquark-antidiquark configurations. The magnetic dipole moments for the members are extracted as ${\mu }_{T_{cc\bar{u}\bar{d}}}=1.17_{-0.32}^{+0.44}{\mu }_N$, ${\mu }_{T_{cc\bar{u}\bar{s}}}=1.35_{-0.37}^{+0.50}{\mu }_N$, ${\mu }_{T_{cc\bar{d}\bar{s}}}=-2.69_{-0.75}^{+1.02}{\mu }_N$, ${\mu }_{T_{cc\bar{u}\bar{u}}}=1.33_{-0.40}^{+0.56}{\mu }_N$, ${\mu }_{T_{cc\bar{d}\bar{d}}}=1.41_{-0.43}^{+0.57}{\mu }_N$ and ${\mu }_{T_{cc\bar{s}\bar{s}}}=1.44_{-0.41}^{+0.53}{\mu }_N$. Comparing the results obtained for the magnetic dipole moments of the $T_{cc\bar{u}\bar{d}}$ state with the $T_{cc\bar{u}\bar{s}}$ state, the $U$-symmetry is seen to be broken at about $\%15$, while for the $T_{cc\bar{d}\bar{d}}$ and $T_{cc\bar{s}\bar{s}}$ states, this symmetry is minimally broken. The obtained results may be useful to determine the true nature of these new interesting states.

   hep-phhep-exhep-latPRD(2024)·11 citations
2. 02*

   Recent developments in testable leptogenesis

   Yannis Georis🇧🇪

   Low-scale leptogenesis is an attractive explanation for the observed baryon asymmetry of our universe that can be tested at a variety of laboratory experiments. In these proceedings, we review some recent advances in this field. In particular, we find that the viable parameter space is strongly enhanced, compared to the minimal case with two right-handed neutrinos, when a third generation is considered and explore the impact of such enhancement on the testability of the scenario. Finally, we also look at the impact of specific flavour and CP symmetries on said parameter space.

   hep-phActa Phys.Polon.Supp.(2024)·2 citations
3. 03*

   Possible Dark Matter Signals from White Dwarfs

   Jia-Shu Niu🇨🇳 · Hui-Fang Xue🇨🇳

   In our galaxy, the white dwarfs (WDs) will inevitably capture the dark matter (DM) particles streaming through them, if there exist interactions between DM particles and nuclei/electrons. At the same time, these DM particles can also be evaporated by the nuclei/electrons in a WD if they have proper mass and the WD is not too cold. The evaporation of DM particles will lead to a faster cooling evolution than that predicted by the stellar evolution theory. In this work, we ascribe the faster cooling evolution of three observed WDs to the capture and evaporation of DM particles, and get the possible DM particle's mass and DM-electron cross section as follows: for $F(q)=1$, $40\mathrm{MeV}/c^2\lesssim m_{\chi }\lesssim 70\mathrm{MeV}/c^2$ and $10^{-57}{\mathrm{cm}}^2\lesssim {\sigma }_{\chi ,e}\lesssim 10^{-55}{\mathrm{cm}}^2$; for $F(q)=(\alpha m_e{)}^2/q^2$, $30\mathrm{MeV}/c^2\lesssim m_{\chi }\lesssim 60\mathrm{MeV}/c^2$ and $10^{-53}{\mathrm{cm}}^2\lesssim {\sigma }_{\chi ,e}\lesssim 10^{-51}{\mathrm{cm}}^2$. These results are beyond the detection capabilities of current direct detection experiments and should be cross checked by more novel scenarios in the future.

   hep-phastro-ph.COastro-ph.SR8 citations
4. 04*

   Toward an estimate of the amplitude $X(3872)\to {\pi }^0{\chi }_{c1}(1P)$

   N. N. Achasov🇷🇺 · G. N. Shestakov🇷🇺

   The well-known model of the triangle diagrams with $D^{\ast }\bar{D}{D}^{\ast }$ and ${\bar{D}}^{\ast }D{\bar{D}}^{\ast }$ mesons in the loops is compared with the modern data on the amplitude of the $X(3872)\to {\pi }^0{\chi }_{c1}(1P)$ decay. Considering the $X(3872)$ object as a ${\chi }_{c1}(2P)$ charmonium state, we introduce a parameter $\xi$ characterizing the scale of the isotopic symmetry violation in this decay and find a lower limit of $\xi \simeq 0.0916$. The model incorporates the only fitted parameter associated with the form factor. We analyze in detail the influence of the form factor on the amplitude $X(3872)\to {\pi }^0{\chi }_{c1}(1P)$ and on the parameter $\xi$. As the suppression of the amplitude by the form factor increases, $\xi$ increases. Due to the fact that the $X(3872)$ resonance is located practically at the threshold of the $D^0{\bar{D}}^{\ast 0}$ channel, the amplitude of $X(3872)\to {\pi }^0{\chi }_{c1}(1P)$ turns out to be proportional to $\sqrt{m_d-m_u}$. Using the estimating values for the coupling constants $g_{XD{\bar{D}}^{\ast }}$, $g_{{\chi }_{c1}D{\bar{D}}^{\ast }}$, and $g_{D^{\ast 0}{D}^{\ast 0}{\pi }^0}$, we show that the model of the triangle loop diagrams is in reasonable agreement with the available data. Apart from the difference in the masses of neutral and charged charmed mesons, any additional exotic sources of isospin violation in $X(3872)\to {\pi }^0{\chi }_{c1}(1P)$ (such as a significant difference between the coupling constants $g_{X{D}^0{\bar{D}}^{\ast 0}}$ and $g_{X{D}^{+}{D}^{\ast -}}$) are not required to interpret the data. This indirectly confirms the isotopic neutrality of the $X(3872)$, which is naturally realized for the $c\bar{c}$ state ${\chi }_{c1}(2P)$.

   hep-phhep-exnucl-thPRD(2024)·10 citations
5. 05*

   Lee-Yang edge singularities in QCD via the Dyson-Schwinger Equations

   Zi-Yan Wan🇨🇳 · Yi Lu🇨🇳 · Fei Gao🇨🇳 · Yu-Xin Liu🇨🇳

   We take the Dyson-Schwinger Equation approach of QCD for the quark propagator at complex chemical potential to study the QCD phase transition. The phase transition line of the $(2+1)$-flavor QCD matter in the imaginary chemical potential region is computed via a simplified truncation scheme, whose curvature is found to be consistent with the one at real chemical potential. Moreover, the computation in the complex chemical potential plane allows us to determine the location of the Lee-Yang edge singularities. We show explicitly that the critical end point coincides with the Lee-Yang edge singularities on the real ${\mu }_B^{}$ axis. We also investigate the scaling behavior of the singularities and discuss the possibility of extrapolating the CEP from a certain range of chemical potential.

   hep-phhep-thnucl-thEPJC(2024)·10 citations
6. 06*

   Comprehensive constraints on fermionic dark matter-quark tensor interactions in direct detection experiments

   Jin-Han Liang (South China Normal U.)🇨🇳 · Yi Liao (South China Normal U.)🇨🇳 · Xiao-Dong Ma (South China Normal U.)🇨🇳 · Hao-Lin Wang (South China Normal U.)🇨🇳

   Effective field theory (EFT) provides a model-independent framework for interpreting the results of dark matter (DM) direct detection experiments. In this study, we demonstrate that the two fermionic DM-quark tensor operators, $(\bar{\chi }i{\sigma }^{\mu \nu }{\gamma }^5\chi )(\bar{q}{\sigma }_{\mu \nu }q)$ and $(\bar{\chi }{\sigma }^{\mu \nu }\chi )(\bar{q}{\sigma }_{\mu \nu }q)$, can contribute to the DM electric and magnetic dipole moments via nonperturbative QCD effects, in addition to the well-studied contact DM-nucleon operators. We then investigate the constraints on these two operators by considering both the contact and the dipole contributions using the XENON1T nuclear recoil and Migdal effect data. We also recast other existing bounds on the DM dipole operators, derived from electron and nuclear recoil measurements in various direct detection experiments, as constraints on the two tensor operators. For $m_{\chi }\lesssim 1\mathrm{GeV}$, our results significantly extend the reach of constraints on the DM-quark tensor operators to masses as low as $5\mathrm{MeV}$, with the bound exceeding that obtained by the Migdal effect with only contact interactions by an order of magnitude or so. In particular, for the operator $(\bar{\chi }{\sigma }^{\mu \nu }i{\gamma }_5\chi )(\bar{q}{\sigma }_{\mu \nu }q)$ with DM mass $m_{\chi }\gtrsim 10\mathrm{GeV}$, the latest PandaX constraint on the DM electric dipole moment puts more stringent bounds than the previous direct detection limit.

   hep-phCPC(2024)·10 citations
7. 07*

   Importance of strange sea to the charge radii and quadrupole moment of $J^P={\frac{1}{2}}^{+},{\frac{3}{2}}^{+}$ baryons

   Preeti Bhall🇮🇳 · A. Upadhyay🇮🇳

   A statistical framework in conjugation with the principle of detailed balance is employed to examine the low-energy properties i.e. charge radii and quadrupole moment of J${}^P$=${\frac{1}{2}}^{+}$ octet and J${}^P$=${\frac{3}{2}}^{+}$ decuplet baryon. The statistical approach assumes the expansion of baryonic system in terms of quark-gluon Fock states. We systematically apply operator formalism along with the statistical approach to study the charge radii and quadrupole moment of baryons. Based on the probabilities of all possible Fock states in spin, flavor and color space, the importance of sea with quarks and gluons is studied. The individual contribution of the constituent quarks and sea which contains terms of scalar, vector and tensor is explored. Due to large mass difference between strange and non-strange content, the SU(3) breaking effect are also investigated. The extent to which strange quark-antiquark pair is considered in sea is constrained by the mass of hadrons, the free energy of gluons in conformity with experimental indications. We focus on the individual contribution of strange and non-strange sea (g, $⟨u\bar{u}⟩$, $⟨d\bar{d}⟩$ and $⟨s\bar{s}⟩$) accomodability in the respective hadrons for their charge radii and quadrupole moment. The present work has been compared with various theoretical approaches and some known experimental observations. Our computed results may provide important information for upcoming experimental findings.

   hep-phnucl-thPTEP(2024)·3 citations
8. 08*

   Beyond the Narrow-Width Limit for Off-Shell and Boosted Differential Top Quark Decays

   André H. Hoang🇦🇹 · Simon Plätzer🇦🇹 · Christoph Regner🇦🇹 · Ines Ruffa🇦🇹

   The standard approaches for describing top quark production and its decay dynamics are currently mostly either based on the narrow-width (NW) limit or on off-shell fixed-order calculations. In this article we present a factorised approach for boosted top quarks that combines the properties of the NW limit and off-shell computations accounting for the dominant off-shell effects in an expansion in $m_t/Q$ with the hard scattering scale $Q$. We discuss the key ideas of our approach and show some preliminary results at tree-level.

   hep-ph1 citation
9. 09*

   Top-philic ALP phenomenology at the LHC

   Simone Tentori🇧🇪

   I present an exploration of the LHC phenomenology of the so-called top-philic ALP in the mass range between tens and hundreds of GeV. Searches through resonant production, such as ALP production in association with a $t\bar{t}$ pair are shown to be complementary to precision measurements of $t\bar{t}$ and $t\bar{t}t\bar{t}$ final states. The case where the ALP decays invisibly is also considered looking at final states with missing energy signatures.

   hep-phhep-ex3 citations
10. 10*

    Form factors of $B_{(s)}$ to light scalar mesons with the $B$-meson LCSR

    R. Khosravi🇮🇷

    In this work, the transition form factors of the semileptonic decays of $B_{(s)}$ to the light scalar mesons with masses close to $1.5\mathrm{GeV}$ such as $K_0^{\ast }(1430),a_0(1450)$, and $f_0(1500)$ are calculated in the framework of the light-cone sum rules (LCSR). For this purpose, the two- and three-particle $B$-meson distribution amplitudes (DA's) are used. Note that it is possible to use the $B$-meson DA's for $B_s$-meson in the $\mathrm{SU}(3{)}_{\mathrm{F}}$ symmetry limit. The transition form factors are obtained in terms of the two-particle DA's up to twist-five accuracy, and the three-particle up to twist-six level. We apply two classes of the phenomenological models for the DA's of $B$-meson. The longitudinal lepton polarization asymmetries and branching fractions for the semileptonic decays of $B_{(s)}$ to the light scalar mesons are estimated with the help of these form factors.

    hep-phPRD(2024)·4 citations
11. 11*

    Heavy axial-vector structures $bb\overline{c}\overline{c}$

    S. S. Agaev🇦🇿 · K. Azizi🇮🇷 · H. Sundu🇹🇷

    The fully heavy axial-vector diquark-antidiquark structures $bb\overline{c}\overline{c}$ are explored by means of the QCD sum rule method. They are modeled as four-quark mesons $T_1$ and $T_2$ composed of $b^{T}C{\sigma }_{\mu \nu }{\gamma }_{5}b$, $\overline{c}{\gamma }^{\nu }C{\overline{c}}^T$ and $b^{T}C{\gamma }_{\mu }{\gamma }_{5}b$, $\overline{c}C{\overline{c}}^T$ diquarks, respectively. The spectroscopic parameters of the tetraquarks $T_1$ and $T_2$ are determined in the context of the QCD two-point sum rule method. Results obtained for masses of these states $m_1=(12715\pm 86)\mathrm{MeV}$ and $m_2=(13383\pm 92)\mathrm{MeV}$ are used to fix their strong decay channels. The full width $\Gamma (T_1)$ of the diquark-antidiquark state $T_1$ is estimated by considering the processes $T_1\to B_c^{-}{B}_c^{\ast -}$ and $T_1\to B_c^{\ast -}{B}_c^{\ast -}$. The decays to mesons $B_c^{-}{B}_c^{\ast -}$, $B_c^{-}(2S)B_c^{\ast -}$ and $B_c^{\ast -}{B}_c^{\ast -}$ are employed to evaluate $\Gamma (T_2)$. Results obtained for the widths $\Gamma (T_1)=(44.3\pm 8.8)\mathrm{MeV}$ and $\Gamma (T_2)=(82.5\pm 13.7)\mathrm{MeV}$ of these tetraquarks in conjunction with their masses are useful for future experimental studies of fully heavy resonances.

    hep-phhep-exhep-latPLB(2024)·13 citations
12. 12*

    Higgs probes of top contact interactions and their interplay with Higgs self-coupling

    Stefano Di Noi🇮🇹 · Ramona Gröber🇮🇹

    We present a method which relies on loop contributions from four-top SMEFT operators to single Higgs observables to contrain their Wilson coefficients. Such loop-induced terms have a non-trivial interplay with the extraction of the trilinear Higgs coupling. We show that this strategy can, for some operators, lead to more stringent bounds than direct measurement via top quark data. Finally, we mention some recent developements in the treatment of ${\gamma }_5$ in dimensional regularisation in the context of the SMEFT.

    hep-phPoS(2024)·0 citations
13. 13*

    Collider imprints of right handed neutrino magnetic moment operator

    Eung Jin Chun🇰🇷 · Sanjoy Mandal🇰🇷 · Rojalin Padhan🇮🇳

    We consider most general effective Lagrangian up to dimension five, built with Standard Model~(SM) fields and right-handed neutrinos~(RHNs) $N_i$. Assuming that the RHNs are present near the electroweak scale, we study the phenomenology of the RHNs and highlight the differences that arise due to the inclusion of dimension five operators. We specifically focus on the production process $e^{+}{e}^{-}/pp\to N_i{N}_j$ which comes from the dimension five magnetic moment operator. We find that this production process followed by the decay chains such as $N_i\to N_j\gamma$, $N_i\to {\nu }_j\gamma$ and $N_i\to {\ell }^{\pm }jj$ leads to striking collider signatures which might help to probe the Majorana nature of neutrinos. We discuss the current collider constraints on this operator, as well as projected limit at future colliders. In addition, we discuss the stellar-cooling bounds applicable to the RHN mass below 0.1 GeV.

    hep-phPRD(2024)·10 citations
14. 14*

    One-loop corrections to the double-real emission contribution to the zero-jettiness soft function at N3LO in QCD

    Daniel Baranowski🇨🇭 · Maximilian Delto🇩🇪 · Kirill Melnikov🇩🇪 · Andrey Pikelner🇩🇪 · Chen-Yu Wang🇩🇪

    We present an analytic calculation of the one-loop correction to the double-real emission contribution to the zero-jettiness soft function at N3LO in QCD, accounting for both gluon-gluon and quark-antiquark soft final-state partons. We explain all the relevant steps of the computation including the reduction of phase-space integrals to master integrals in the presence of Heaviside functions, and the methods we employed to compute them.

    hep-phJHEP(2024)·11 citations
15. 15*

    Numerically Computing Finite Temperature Loop Integrals using pySecDec

    D. Harnett🇨🇦 · Siyuan Li🇨🇦 · T.G. Steele🇨🇦

    Finite-temperature quantum field theory provides the foundation for many important phenomena in the Standard Model and extensions, including phase transitions, baryogenesis, and gravitational waves. Methods are developed to enable application of pySecDec (a Python-language-based package designed for numerical calculation of dimensionally-regulated loop integrals) to numerically evaluate finite-temperature loop integrals in the imaginary time (Matsubara) formalism. These methods consist of two main elements: an inverse Wick rotation that converts a finite-temperature loop integral into a form applicable to pySecDec, and asymptotic techniques to regulate and accelerate convergence of the Matsubara frequency summations. Numerical pySecDec evaluation of finite-temperature, two-point and three-point, one-loop topologies for scalar fields is used to illustrate and validate these new methodologies. Advantages of these finite-temperature pySecDec numerical methods are illustrated by the inclusion of multiple mass and external momentum scales.

    hep-phhep-thEPJA(2024)·1 citation
16. 16*

    Inhomogeneous Kinetic Equation for Mixed Neutrinos: Tracing the Missing Energy

    Damiano F. G. Fiorillo🇩🇰 · Georg G. Raffelt🇩🇪 · Günter Sigl🇩🇪

    Flavor-dependent neutrino transport is described by a well-known kinetic equation for occupation-number matrices in flavor space. However, as an overlooked theoretical problem, we show that in the inhomogeneous case, neutrino-neutrino refractive energy is not conserved. We derive the missing gradient terms in the fast flavor limit (vanishing neutrino masses), and prove that the missing refractive energy is traded with the huge reservoir of neutrino kinetic energy through gradients of the weak interaction potential. Even small changes of the kinetic energy accommodate the refractive energy gained or lost. Flavor evolution alone is negligibly affected by the new terms.

    hep-phastro-ph.COastro-ph.HEPRL(2024)·40 citations
17. 17*

    New dark matter analysis of Milky Way dwarf satellite galaxies with MADHATv2

    Kimberly K. Boddy🇺🇸 · Zachary J. Carter🇺🇸 · Jason Kumar🇺🇸 · Luis Rufino🇺🇸 · Pearl Sandick🇺🇸 · Natalia Tapia-Arellano🇺🇸

    We obtain bounds on dark matter annihilation using 14 years of publicly available Fermi-LAT data from a set of 54 dwarf spheroidal galaxies, using spectral information from 16 energy bins. We perform this analysis using our updated and publicly available code MADHATv2, which can be used to test a variety of models for dark matter particle physics and astrophysics in an accessible manner. In particular, we note that including Carina III in the analysis strengthens constraints on $s$-wave annihilation into two-body Standard Model final states by a factor of $\sim 3$ but broadens the error on the constraint due to the large uncertainty of its $J$-factor. Our findings illustrate the importance of verifying if Carina III is in fact a dwarf spheroidal galaxy and measuring more precisely its $J$-factor. More generally, they highlight the significance of forthcoming discoveries of nearby ultra-faint dwarfs for dark matter indirect detection.

    hep-phastro-ph.COPRD(2024)·11 citations
18. 18*

    Insight into Emergence of Hadron Mass from $\text{boldmath}{N}^{\ast }$ Electroexcitation Amplitudes

    V.I. Mokeev🇺🇸 · D.S. Carman🇺🇸

    The emergence of hadron mass represents one of the most challenging and still open problems in contemporary hadron physics. The results on the nucleon resonance electroexcitation amplitudes available from the CLAS data on $\pi N$ and ${\pi }^{+}{\pi }^{-}p$ electroproduction analyzed within the continuum Schwinger method open up a new avenue for gaining insight into the strong interaction dynamics that are responsible for the generation of the dominant part of hadron mass. Future prospects of these studies in experiments of the 12-GeV era with CLAS12 and after a potential increase of the CEBAF energy up to 22 GeV will offer a unique opportunity to explore the full range of distances where the dominant part of hadron mass and $N^{\ast }$ structure emerge from QCD.

    ↳ nucl-exhep-phNuovo Cim.C(2024)·4 citations
19. 19*

    Understanding the nature of baryon resonances

    Derek B. Leinweber🇦🇺 · Curtis D. Abell🇦🇺 · Liam C. Hockley🇦🇺 · Waseem Kamleh🇦🇺 · Zhan-Wei Liu🇨🇳 · Finn M. Stokes🇦🇺 · Anthony W. Thomas🇦🇺 · Jia-Jun Wu🇨🇳

    This presentation opens with a brief review of lattice QCD calculations showing the $2s$ radial excitation of the nucleon sits at approximately 2 GeV, well above the Roper resonance position. We then proceed to reconcile this observation with experimental scattering data. While the idea of dressing quark-model states in a coupled-channel analysis to describe scattering data has been around for decades, it's now possible to bring these descriptions to the finite-volume of lattice QCD for confrontation with lattice-QCD calculations. This combination of lattice QCD and experiment demands that we reconsider our preconceived notions about the quark-model and its excitation spectrum. We close with a discussion of an unanticipated resolution to the missing baryon resonances problem.

    ↳ hep-lathep-phnucl-thNuovo Cim.C(2024)·12 citations
20. 20*

    Self-interacting dark matter interpretation of Crater II

    Xingyu Zhang🇨🇳 · Hai-Bo Yu🇺🇸 · Daneng Yang🇺🇸 · Haipeng An🇨🇳

    The satellite galaxy Crater II of the Milky Way is extremely cold and exceptionally diffuse. These unusual properties are challenging to understand in the standard model of cold dark matter. We investigate the formation of Crater II in self-interacting dark matter (SIDM), where dark matter particles can scatter and thermalize. We conduct a series of controlled N-body simulations to model the tidal evolution of Crater II, varying the self-interacting cross section, orbit parameters, and initial stellar distribution. Dark matter self-interactions lead to halo core formation and the distribution of stars expands accordingly. A cored SIDM halo also boosts tidal mass loss, allowing for a high orbit. Our simulations show that SIDM halos with a $1\mathrm{kpc}$ core can simultaneously explain the low stellar velocity dispersion and the large half-light radius of Crater II, remaining robust to the initial distribution of stars. For the orbit motivated by the measurements from Gaia Early Data Release 3, the favored self-interacting cross section is approximately $60\mathrm{c}{\mathrm{m}}^2/g$ on the mass scale of Crater II.

    ↳ astro-ph.GAhep-phApJL(2024)·29 citations
21. 21*

    Light Hypernuclei Production in Au+Au Collisions at $\sqrt{s_{NN}}=$ 3 GeV within Thermodynamic Approach

    M. Kozhevnikova🇷🇺 · Yu. B. Ivanov🇷🇺

    Simulations of the $\Lambda$-hyperon and light-hypernuclei production in Au+Au collisions at $\sqrt{s_{NN}}=$ 3 GeV were performed within updated Three-fluid Hydrodynamics-based Event Simulator Extended by UrQMD (Ultra-relativistic Quantum Molecular Dynamics) final State interactions (THESEUS). The light (hyper)nuclei are treated thermodynamically, i.e. they are considered on the equal basis with hadrons. The only additional parameter is related to the late freeze-out that imitates the afterburner stage for the light (hyper)nuclei because the UrQMD is not able to dynamically treat them. The calculation of hypernuclei production is completely similar to that of light nuclei. The hypernuclei results are compared with recent STAR data. It is found that the calculated midrapidity ${}_{\Lambda }^3$H/$\Lambda$ ratio falls within the error bars of the experimental point. It is remarkable that large difference between the $t/p$ and ${}_{\Lambda }^3$H/$\Lambda$ ratios is reproduced without any additional parameters. Rapidity distributions of ${}_{\Lambda }^3$H/$\Lambda$ and ${}_{\Lambda }^4$He/$\Lambda$ ratios are predicted. Midrapidity mean transverse momenta of protons, $\Lambda$s and light (hyper)nuclei in central collisions well agree with the data. The calculated directed flow also reasonably well reproduces of the data.

    ↳ nucl-thhep-phnucl-exPRC(2024)·7 citations
22. 22*

    Can fallback accretion on magnetar model power the X-ray flares simultaneously observed with gamma-rays of Gamma-ray bursts?

    Wen-Yuan Yu · Hou-Jun Lü🇨🇳 · Xing Yang🇨🇳 · Lin Lan · Zhe Yang🇯🇵

    The prompt emission, X-ray plateau, and X-ray flares of Gamma-ray bursts (GRB) are thought to be from internal dissipation, and the magnetar as the central engine with propeller fallback accretion is proposed to interpret the observed phenomena of GRBs. In this paper, by systematically searching for X-ray emission observed by Swift/Xry Telescope, we find that seven robust GRBs include both X-ray flares and plateau emissions with measured redshift. More interestingly, the X-ray flares/bumps for those seven GRBs are simultaneously observed in the gamma-ray band. By adopting the propeller fallback accretion model to fit the observed data, it is found that the free parameters of two GRBs (140512A and 180329B) can be constrained very well, while in the other five cases, more or less, they are not all sufficiently constrained. On the other hand, this requires that the conversion efficiency of the propeller is to be two or three times higher than that of the spindown dipole radiation of the magnetar. If this is the case, it is contradictory to the expectation from the propeller model: namely, a dirtier ejecta should be less efficient in producing gamma-ray emissions. Our results hint that at least the magnetar central engine with propeller fallback accretion model cannot interpret very well both the GRB X-ray flares simultaneously observed in the gamma-ray band and the X-ray flares of GRBs with a high Lorentz factor.

    ↳ astro-ph.HEhep-phApJ(2024)·7 citations
23. 23*

    The Jet Composition of GRB 230307A: Poynting-Flux-Dominated Outflow?

    Zhao-Wei Du🇨🇳 · HouJun Lü🇨🇳 · Xiaoxuan Liu🇨🇳 · EnWei Liang🇨🇳

    The jet composition of GRB plays an important role in understanding the energy dissipation and radiation mechanisms in GRB physics, but it is poorly constrained from the observational data. Recently, an interesting long-duration GRB 230307A with redshift $z=$0.065 has attracted great attention. The lack of detected thermal emission and mini-structure of prompt emission lightcurve of this burst suggest that the outflow is Poynting-flux-dominated and point towards the ICMART model. In this paper, we invoke two independent methods to investigate the jet composition of GRB 230307A. The high magnetization parameter ($\sigma >7$ or ever large) for$R_0=10^{10}$ cm that is used to suppress thermal component, strongly suggests that a significant fraction of the outflow energy is likely in a Poynting flux entrained with the baryonic matter. Moreover, it is found that the radiation efficiency of this burst for typical values ${ϵ}_e=0.1$ and ${ϵ}_B=0.01$ can reach as high as $50\%$ which disfavors the internal shock model, but is consistent with ICMART model. Finally, a possible unified picture to produce GRB 230307A originated from a compact star merger is also discussed.

    ↳ astro-ph.HEhep-phMNRAS(2023)·16 citations
24. 24*

    Exploring the QCD phase diagram with three flavors of Möbius domain wall fermions

    Yu Zhang🇯🇵 · Yasumichi Aoki🇯🇵 · Shoji Hashimoto🇯🇵 · Issaku Kanamori🇯🇵 · Takashi Kaneko🇯🇵 · Yoshifumi Nakamura🇯🇵

    We present an update on the study of the QCD phase transition with 3 flavors of Möbius domain wall fermions at zero baryon density. We performed simulations on lattices of size $36^3\times 12\times 16$ and $24^3\times 12\times 32$ with a variety of quark masses at a fixed lattice spacing $a=0.1361(20)$ fm, which correspond to a temperature 121(2) MeV. By analyzing the chiral condensate, chiral susceptibilitities and Binder cumulant on $36^3\times 12\times 16$ lattices together with the result obtained from our previous study on $24^3\times 12\times 16$ lattices, we identified a crossover occurring at quark mass around $m_q^{\overline{\mathrm{MS}}}(2\mathrm{GeV})\sim 3-4$ MeV for this temperature. Besides, we show the effects of residual chiral symmetry breaking on chiral condensate and chiral susceptibilities between $L_s=16$ and 32.

    ↳ hep-lathep-phhep-thnucl-thPoS(2024)·11 citations
25. 25*

    Search for Long-lived Particles at Future Lepton Colliders Using Deep Learning Techniques

    Yulei Zhang🇨🇳 · Cen Mo🇨🇳 · Xiang Chen🇨🇳 · Bingzhi Li🇨🇳 · Hongyang Chen🇨🇳 · Jifeng Hu🇨🇳 · Liang Li🇨🇳

    Long-lived particles (LLPs) provide an unambiguous signal for physics beyond the Standard Model (BSM). They have a distinct detector signature, with decay lengths corresponding to lifetimes of around nanoseconds or longer. Lepton colliders allow LLP searches to be conducted in a clean environment, and such searches can reach their full physics potential when combined with machine learning (ML) techniques.This experimental study, utilizing comprehensive full simulation data samples, focuses on LLP searches resulting from Higgs decay in $e^{+}{e}^{-}\to ZH$. We demonstrate that, by employing deep neural network approaches the LLP signal efficiency can be improved up to 95\% for an LLP mass around 50 GeV and a lifetime of approximately 1 nanosecond, while rejecting all SM backgrounds. Furthermore, the signal sensitivity for the branching ratio of Higgs decaying into LLPs reaches a state-of-art limit of $1.0\times 10^{-6}$ with a statistics of $4\times 10^6$ Higgs.

    ↳ hep-exhep-phFront.Phys.(2026)·8 citations
26. 26*

    Progress in meson-meson scattering at large $N_{\text{c}}$

    Jorge Baeza-Ballesteros🇪🇸 · Pilar Hernández🇪🇸 · Fernando Romero-López🇺🇸

    We study the large $N_{\text{c}}$ scaling of meson-meson scattering amplitudes in a theory with $N_{\text{f}}=4$ degenerate quark flavors. We focus on two different scattering channels, one having the same quantum numbers as some recently found tetraquark states at LHCb. Using Lüscher's formalism, we study the $N_{\text{c}}$ dependence of the scattering phase shift and investigate the presence of exotic resonances in the scattering amplitude. We analyze the impact of including two-vector-meson and tetraquark-like operators to extract the finite-volume energies.

    ↳ hep-lathep-phPoS(2024)·6 citations
27. 27*

    diffSph: a Python tool to compute diffuse signals from dwarf spheroidal galaxies

    Martin Vollmann🇩🇪 · Finn Welzmüller🇩🇪 · Lovorka Gajović🇩🇪

    So far no diffuse emissions in dwarf spheroidal satellites of the Milky Way have ever been observed. Given that dwarf galaxies are predominantly composed of Dark Matter, the discovery of these signals could offer valuable insights into understanding the nature of Dark Matter. We present "diffSph", a Python tool which in its present version provides fast predictions of such diffuse signals in radio frequencies. It also features a very comprehensive module for the computation of "J" and "D" factors that are relevant for indirect Dark Matter detection using gamma rays. Routines are coupled to parton-shower algorithms and Dark Matter halo mass functions from state-of-the-art kinematic fits. This code is also useful for testing generic hypotheses (not necessarily associated with any Dark Matter candidate) about the cosmic-ray electron/positron sources in the dwarf galaxies. The diffSph tool has already been employed in searches for diffuse signals from dwarf spheroidal galaxies using the LOw Frequency ARray (LOFAR).

    ↳ astro-ph.HEastro-ph.GAhep-phJCAP(2024)·0 citations
28. 28*

    Leptogenesis Effects on the Gravitational Waves Background: Interpreting the NANOGrav Measurements and JWST Constraints on Primordial Black Holes

    K. El Bourakadi🇲🇦 · H.Chakir🇲🇦 · M.Yu. Khlopov🇷🇺

    We demonstrate that the leptogenesis mechanisms, which are associated with B-L symmetry breaking mechanism has notable effects on the production of gravitational waves. These gravitational waves align well with the recent observations of a stochastic gravitational wave background by NANOGrav and pulsar-timing arrays (PTAs). For these gravitational waves to match the recent measurements, the critical value of the B-L breaking should be around the GUT scale. Moreover, we consider the generation of primordial gravitational waves from binary systems of Primordial Black Holes (PBHs) which could be predicted by the recent detection of gravitational waves. PBHs with specific masses can be responsible for massive galaxy formation observed at high redshifts reported by the James Webb Space Telescope (JWST). We contemplate the potential for a shared source between the NANOGrav and JWST observations, namely primordial black holes. These black holes could serve as seeds of rapid galaxy formation, offering an explanation for the galaxies observed by JWST.

    ↳ gr-qchep-phhep-thJCAP(2024)·2 citations
29. 29*

    NLSM $\subset$ Tr$({\varphi }^3)$

    Nima Arkani-Hamed🇺🇸 · Qu Cao🇨🇳 · Jin Dong🇨🇳 · Carolina Figueiredo🇺🇸 · Song He🇨🇳

    Scattering amplitudes for the simplest theory of colored scalar particles - the Tr(${\Phi }^3$) theory - have recently been the subject of active investigations. In this letter we describe an unanticipated wider implication of this work: the Tr(${\Phi }^3$) theory secretly contains Non-linear Sigma Model (NLSM) amplitudes to all loop orders. The NLSM amplitudes are obtained from Tr$({\Phi }^3)$ amplitudes by a unique shift of kinematic variables. We show that this shifted kinematics produces amplitudes for a cubic theory with a linear term in potential, with extrema spontaneously breaking $U(N)\to U(N-k)\times U(k)$. The Goldstone amplitudes for this theory coincide with those of pions in the $U(N)\times U(N)\to U(N)$ chiral Lagrangian to all orders in the planar limit. We also give a purely on-shell understanding of this correspondence, showing integrands defined by the kinematic shifts have the correct residues on poles and appropriately produce the Adler zero. Finally, we discuss how similar kinematic shifts produce certain infinite classes of mixed amplitudes of pions and Tr(${\Phi }^3$) scalars, most of which are not interpretable from the Lagrangian description.

    ↳ hep-thhep-phPRD(2024)·65 citations
30. 30*

    A Cold-Atom Particle Collider

    Guo-Xian Su🇨🇳 · Jesse Osborne🇦🇺 · Jad C. Halimeh🇩🇪

    A major objective of the strong ongoing drive to realize quantum simulators of gauge theories is achieving the capability to probe collider-relevant physics on them. In this regard, a highly pertinent and sought-after application is the controlled collisions of elementary and composite particles, as well as the scattering processes in their wake. Here, we propose particle-collision experiments in a cold-atom quantum simulator for a $1+1$D $\mathrm{U}(1)$ lattice gauge theory with a tunable topological $\theta$-term, where we demonstrate an experimentally feasible protocol to impart momenta to elementary (anti)particles and their meson composites. We numerically benchmark the collisions of moving wave packets for both elementary and composite particles, uncovering a plethora of rich phenomena, such as oscillatory string dynamics in the wake of elementary (anti)particle collisions due to confinement. We also probe string inversion and entropy production processes across Coleman's phase transition through far-from-equilibrium quenches. We further demonstrate how collisions of composite particles unveil their internal structure. Our work paves the way towards the experimental investigation of collision dynamics in state-of-the-art quantum simulators of gauge theories, and sets the stage for microscopic understanding of collider-relevant physics in these platforms.

    ↳ cond-mat.quant-gashep-exhep-lathep-ph+1PRX Quantum(2024)·61 citations
31. 31*

    Observables from classical black hole scattering in Scalar-Tensor theory of gravity from worldline quantum field theory

    Arpan Bhattacharyya🇮🇳 · Debodirna Ghosh🇮🇳 · Saptaswa Ghosh🇮🇳 · Sounak Pal🇮🇳

    In this article, we compute the two observables, impulse and waveform, in a black hole scattering event for the Scalar-Tensor theory of gravity with a generic scalar potential using the techniques of Worldline Quantum Field Theory. We mainly investigate the corrections to the above mentioned observables due to the extra scalar degree of freedom. For the computation of impulse, we consider the most general scenario by making the scalar field massive and then show that each computed diagram has a smooth massless limit. We compute the waveform for scalar and graviton up to 2PM, taking the scalar as massless. Furthermore, we discuss if the scalar has mass and how the radiation integrals get more involved than the massless case. We also arrive at some analytical results using stationary phase approximation.

    ↳ hep-thgr-qchep-phJHEP(2024)·29 citations
32. 32*

    Dark matter decay in the Milky Way halo

    Mark R. Lovell (Durham University)🇮🇸

    Dark matter may be detected in X-ray decay, including from the decay of the dark matter particles that make up the Milky Way (MW) halo. We use a range of density profiles to compute X-ray line intensity profiles, with a focus on the resonantly produced sterile neutrino dark matter candidate. Compared to the Navarro--Frenk--White density profile, we show that using an adiabatically contracted halo profile suppresses the line intensity in the halo outskirts and enhances it in the Galactic Centre (GC), although this enhancement is eliminated by the likely presence of a core within 3~kpc. Comparing our results to MW halo observations, other X-ray observations, and structure formation constraints implies a sterile neutrino mixing angle parameter $s_{11}\equiv {\sin }^2(2\theta )\times 10^{11}\sim [3,4]$ (particle lifetime ${\tau }_{28}\equiv \tau /(10^{28}\sec )\sim [1.0,1.3]$), which is nevertheless is strong tension with some reported non-detections. We make predictions for the likely decay flux that the XRISM satellite would measure in the GC, plus the Virgo and Perseus clusters, and outline further steps to determine whether the dark matter is indeed resonantly produced sterile neutrinos as detected in X-ray decay.

    ↳ astro-ph.COastro-ph.GAhep-phMNRAS(2024)·3 citations
33. 33*

    Trace anomaly form factors from lattice QCD

    Bigeng Wang🇺🇸 · Fangcheng He🇺🇸 · Gen Wang🇫🇷 · Terrence Draper🇺🇸 · Jian Liang🇨🇳 · Keh-Fei Liu🇺🇸 · Yi-Bo Yang🇨🇳

    The hadron mass can be obtained through the calculation of the trace of the energy-momentum tensor in the hadron which includes the trace anomaly and sigma terms. The anomaly due to conformal symmetry breaking is believed to be an important ingredient for hadron mass generation and confinement. In this work, we will present the calculation of the glue part of the trace anomaly form factors of the pion up to $Q^2\sim 4.3{\mathrm{GeV}}^2$ and the nucleon up to $Q^2\sim 1{\mathrm{GeV}}^2$. The calculations are performed on a domain wall fermion ensemble with overlap valence quarks at seven valence pion masses varying from $\sim 250$ to $\sim 540$ MeV, including the unitary point $\sim 340$ MeV. We calculate the radius of the glue trace anomaly for the pion and the nucleon from the $z$ expansion. By performing a two-dimensional Fourier transform on the glue trace anomaly form factors in the infinite momentum frame with no energy transfer, we also obtain their spatial distributions for several valence quark masses. The results are qualitatively extrapolated to the physical valence pion mass with systematic errors from the unphysical sea quark mass, discretization effects in the renormalization sum rule, and finite-volume effects to be addressed in the future. We find the pion's form factor changes sign, as does its spatial distribution, for light quark masses. This explains how the trace anomaly contribution to the pion mass approaches zero toward the chiral limit.

    ↳ hep-lathep-phnucl-thPRD(2024)·35 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.