The European Physical Journal C最新文献_第8页

Universality of the baryon axial vector current operator in large-(N_c) chiral perturbation theory 大- (N_c)手性微扰理论中重子轴矢量电流算子的普适性

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14790-x

Rubén Flores-Mendieta, Guillermo Sánchez-Almanza

{"title":"Universality of the baryon axial vector current operator in large-(N_c) chiral perturbation theory","authors":"Rubén Flores-Mendieta, Guillermo Sánchez-Almanza","doi":"10.1140/epjc/s10052-025-14790-x","DOIUrl":"10.1140/epjc/s10052-025-14790-x","url":null,"abstract":"<div>The baryon axial vector current is computed in a combined formalism in (1/N_c) and chiral corrections. Flavor SU(3) symmetry breaking is accounted for in two ways: Implicitly through the integrals occurring in the one-loop graphs and explicitly through perturbative symmetry breaking. Loop integrals can be expanded in a power series in the ratio of the decuplet-octet baryon mass difference to the pseudoscalar meson mass and the first three terms in the series are retained and evaluated. The universal baryon axial vector current so constructed is neither diagonal nor off-diagonal in the sense that it can connect baryon states of either different or equal spins to obtain appropriate axial vector couplings. Processes of interest are found in octet-baryon and decuplet-baryon semileptonic decays and strong decays of decuplet baryons. A fit to the available experimental information is performed to determine the free parameters in the formalism, which allows one to estimate, for instance, the leading axial vector coupling in the semileptonic decays (Omega ^- rightarrow Xi ^0 ell ^-overline{nu }_ell ) and (Omega ^- rightarrow {Xi ^*}^0ell ^-overline{nu }_ell ).\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 9","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14790-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Weak decays of the (varvec{B_s}) meson in the self-consistent covariant light-front approach 自洽协变光前方法中(varvec{B_s})介子的弱衰减

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14677-x

S. Thejus Mary, Rohit Dhir

{"title":"Weak decays of the (varvec{B_s}) meson in the self-consistent covariant light-front approach","authors":"S. Thejus Mary, Rohit Dhir","doi":"10.1140/epjc/s10052-025-14677-x","DOIUrl":"10.1140/epjc/s10052-025-14677-x","url":null,"abstract":"<div>We present a comprehensive study of weak transition form factors and decay observables of the (B_s) meson in transitions to pseudoscalar (P) and vector (V) mesons. The (B_s rightarrow P(V)) form factors are calculated using the self-consistent covariant light-front quark model, with a model-independent z-series expansion calibrated to lattice QCD and phenomenological inputs for quark masses and (beta ) parameters. This enables reliable (q^2)-resolved predictions across the full kinematic range. Based on these form factors, we predict branching ratios and angular observables, including forward–backward asymmetries, polarization fractions, and leptonic convexity parameters for semileptonic decays. Nonleptonic two-body decay rates for (B_s rightarrow PP) and (B_s rightarrow PV) modes are also computed within the standard factorization framework using the same dynamical input. Comparisons with results from lattice QCD, light-cone sum rules, and other approaches are presented, highlighting both theoretical consistency and persistent tensions with experiment.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 9","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14677-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A comprehensive approach to the physics of mesons 介子物理学的综合方法

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14774-x

A. S. Miramontes, J. M. Morgado, J. Papavassiliou, J. M. Pawlowski

{"title":"A comprehensive approach to the physics of mesons","authors":"A. S. Miramontes, J. M. Morgado, J. Papavassiliou, J. M. Pawlowski","doi":"10.1140/epjc/s10052-025-14774-x","DOIUrl":"10.1140/epjc/s10052-025-14774-x","url":null,"abstract":"<div>We develop an inclusive approach for the self-consistent solution of coupled sets of Bethe-Salpeter and Schwinger–Dyson equations in QCD. This framework allows us to maintain the axial Ward-Takahashi identities of the theory within advanced approximation schemes, such as the skeleton or three-particle irreducible expansions. For this purpose we reformulate the Schwinger-Dyson equation of the axial-vector vertex such that the bulk of its quantum corrections is expressed in terms of an effective vertex, containing an additional gluon. Crucially, this vertex satisfies a symmetry-induced relation of its own, which involves the full quark-gluon vertex. As a result, the Schwinger-Dyson equation reproduces the standard Ward-Takahashi identity satisfied by the axial-vector vertex. Consequently, the known relation between the quark mass function and the wave function of the pion in the chiral limit is duly fulfilled. The present approach offers valuable insights into the interplay between symmetry and dynamics, and provides a practical path towards computations of hadron physics within sophisticated approximations. In particular, the one-loop dressed truncation of the key dynamical equations, including that of the quark-gluon vertex, is shown to be completely compatible with the required symmetry relations. Further extensions and potential phenomenological applications of the developed framework are briefly discussed.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 9","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14774-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Flavor-changing phenomenology in a U(1) model U(1)模型中的风味变化现象学

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14803-9

N. T. Duy, D. T. Huong, Duong Van Loi, Phung Van Dong

{"title":"Flavor-changing phenomenology in a U(1) model","authors":"N. T. Duy, D. T. Huong, Duong Van Loi, Phung Van Dong","doi":"10.1140/epjc/s10052-025-14803-9","DOIUrl":"10.1140/epjc/s10052-025-14803-9","url":null,"abstract":"<div>We study family-nonuniversal extensions of the SM, based upon gauge symmetry (SU(3)_C otimes SU(2)_L otimes U(1)_X otimes U(1)_N), where the last two factors determine the hypercharge, (Y=X+N). We consider the third quark family transforming under the gauge symmetry differently from the first two quark families. The setup naturally induces small neutrino masses through the existence of right-handed neutrinos by anomaly cancellation. The nonuniversality of quark families leads to tree-level quark FCNCs coupled to the new gauge boson (Z') and an extended Higgs sector. The FCNCs significantly modify neutral-meson mixings, rare meson decays, and CP-violating observables, which constrain the new physics at TeV. If the first or second quark family transforms differently from the rest of the quark families (opposite to the above case), the new physics contribution is extremely enhanced, bounding the new physics to be much beyond TeV. Hence, the discrepancy of the third quark family is favored, given that the new physics is at TeV. The approach also suggests a flipped model in which the family nonuniversality is translated to the lepton sector; that is, all quark families transform universally, which suppresses the quark FCNCs, whereas lepton families transform nonuniversally, implying lepton FCNCs. Hence, the FCNCs are also transmuted from the quark sector to the lepton sector. A novel aspect of the flipped model is that lepton flavor violation is coupled to the new (Z') boson and new Higgs bosons at the tree level. Additionally, it provides suitable neutrino masses and dark matter candidates via a scotoseesaw scheme. The new physics in the flipped model is bounded at TeV, similar to the original model.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 9","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14803-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erratum: Correlations between maximum mass of neutron stars and the nuclear matter properties and the constraints from PSR J0740+6620 and GW190814 中子星最大质量与核物质性质的相关性及PSR J0740+6620和GW190814的约束

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14678-w

M. Zhou, H. M. Liu, H. Zheng, X. Q. Liu, W. P. Lin, Z. H. Li, A. Bonasera

引用次数: 0

Analysis of the strong vertices (Lambda _cD^{(*)}N^*(1535)) and (Lambda _bB^{(*)}N^*(1535)) in QCD sum rules QCD和规则中强顶点(Lambda _cD^{(*)}N^*(1535))和(Lambda _bB^{(*)}N^*(1535))的分析

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14754-1

Jie Lu, Dian-Yong Chen, Guo-Liang Yu, Zhi-Gang Wang, Ze Zhou

{"title":"Analysis of the strong vertices (Lambda _cD^{(*)}N^*(1535)) and (Lambda _bB^{(*)}N^*(1535)) in QCD sum rules","authors":"Jie Lu, Dian-Yong Chen, Guo-Liang Yu, Zhi-Gang Wang, Ze Zhou","doi":"10.1140/epjc/s10052-025-14754-1","DOIUrl":"10.1140/epjc/s10052-025-14754-1","url":null,"abstract":"<div>In this article, we firstly analyze the mass and pole residue of negative parity nucleon (N^*(1535)) within the two-point QCD sum rules. Basing on these results, we continuously study the strong coupling constants of vertices (Lambda _cDN^*), (Lambda _cD^*N^*), (Lambda _bBN^*) and (Lambda _bB^*N^*) in the framework of three-point QCD sum rules. At hadron side, all possible couplings of interpolating current to hadronic states are considered. At QCD side, the contributions of vacuum condensate terms (langle bar{q}qrangle ), (langle g_s^2GGrangle ), (langle bar{q} g_ssigma Gqrangle ), (langle bar{q}qrangle ^2) and (g_s^2langle bar{q}qrangle ^2) are also considered. By setting the four momentum of (D^{(*)}[B^{(*)}]) mesons off-shell, the strong coupling constants in deep space-like regions ((Q^2=-q^2gg Lambda _{QCD}^2)) are obtained. Then, the momentum dependent coupling constants in space-like regions are fitted into analytical function (G(Q^2)) and are extrapolated into time-like regions ((Q^2<0)). Finally, the on-shell values of strong coupling constants are obtained by taking (Q^{2}=-m_{D^{(*)}[B^{(*)}]}^2). The results are (G_{Lambda _cDN^*}(Q^2=-m_D^2)=4.06^{+0.96}_{-0.75}), (f_{Lambda _cD^*N^*}(Q^2=-m_{D^*}^2)=3.73^{+0.68}_{-0.16}), (g_{Lambda _cD^*N^*}(Q^2=-m_{D^*}^2)=9.22^{+3.16}_{-0.36}), (G_{Lambda _bBN^*}(Q^2=-m_B^2)=9.11^{+1.54}_{-1.61}), (f_{Lambda _bB^*N^*}(Q^2=-m_{B^*}^2)=8.55^{+2.69}_{-2.21}) and (g_{Lambda _bB^*N^*}(Q^2=-m_{B^*}^2)=-,0.25^{+0.16}_{-0.01}).\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 9","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14754-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterization of a GAGG detector for neutron measurements in underground laboratories 用于地下实验室中子测量的GAGG探测器的特性

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14807-5

L. Ascenzo, G. Benato, Y. Chu, G. Di Carlo, A. Molinario, S. Vernetto

{"title":"Characterization of a GAGG detector for neutron measurements in underground laboratories","authors":"L. Ascenzo, G. Benato, Y. Chu, G. Di Carlo, A. Molinario, S. Vernetto","doi":"10.1140/epjc/s10052-025-14807-5","DOIUrl":"10.1140/epjc/s10052-025-14807-5","url":null,"abstract":"<div>In rare events experiments, such as those devoted to the direct search of dark matter, a precise knowledge of the environmental gamma and neutron backgrounds is crucial for reaching the design experiment sensitivity. The neutron component is often poorly known due to the lack of a scalable detector technology for the precise measurement of low-flux neutron spectra. (hbox {Gd}_{3}hbox {Al}_{2}hbox {Ga}_{3}hbox {O}_{12}):Ce (GAGG) is a newly developed, high-density scintillating crystal with a high gadolinium content, which could allow to exploit the high ((n,gamma )) cross section of 155Gd and 157Gd for neutron measurements in underground environments. GAGG crystals feature a high scintillation light yield, good timing performance, and the capability of particle identification via pulse-shape discrimination. In a low-background environment, the distinctive signature produced by neutron capture on gadolinium, namely a (beta /gamma ) cascade releasing up to 9 MeV of total energy, and the efficient particle identification provided by GAGG could yield a background-free neutron capture signal. In this work, we present the characterization of a first GAGG detector prototype in terms of particle discrimination performance, intrinsic radioactive contamination, and neutron response.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 9","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14807-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Isospin kaon anomaly and its consequences 同位旋介子异常及其后果

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14798-3

Francesco Giacosa, Martin Rohrmoser

引用次数: 0

Screened axio-dilaton cosmology: novel forms of early dark energy 筛选轴膨胀宇宙学：早期暗能量的新形式

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-24 DOI: 10.1140/epjc/s10052-025-14735-4

Adam Smith, Philippe Brax, Carsten van de Bruck, C. P. Burgess, Anne-Christine Davis

{"title":"Screened axio-dilaton cosmology: novel forms of early dark energy","authors":"Adam Smith, Philippe Brax, Carsten van de Bruck, C. P. Burgess, Anne-Christine Davis","doi":"10.1140/epjc/s10052-025-14735-4","DOIUrl":"10.1140/epjc/s10052-025-14735-4","url":null,"abstract":"<div>We study the cosmology of multi-field Dark Energy, using a well-motivated axio-dilaton model that contains the minimal number of fields to have the 2-derivative sigma-model interactions that power-counting arguments show naturally compete with General Relativity at low energies. Our analysis differs from earlier, related, studies by treating the case where the dilaton’s couplings to matter are large enough to require screening to avoid unacceptable dilaton-mediated forces in the solar system. We use a recently proposed screening mechanism that exploits the interplay between stronger-than-gravitational axion-matter couplings with the 2-derivative axion-dilaton interactions to suppress the couplings of the dilaton to bulk matter. The required axion-matter couplings also modify cosmology, with the axion’s background energy density turning out to resemble early dark energy. We compute the properties of the axion fluid describing the rapid oscillations of the axion field around the time-dependent minimum of its matter-dependent effective potential, extending the usual formalism to include nontrivial kinetic sigma-model interactions. We explore the implications of these models for the Cosmic Microwave Background and the growth of structure and find that for dilaton potentials of the Albrecht–Skordis form (itself well-motivated by UV physics), successful screening can be consistent with the early dark energy temporarily comprising as much as 10% of the total density in the past. We find that increasing the dilaton-matter coupling decreases the growth of structure due to enhanced Hubble friction, an effect that dominates the usual fifth-force effects that amplify structure growth.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 9","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14735-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Observational appearances of an inner extremal regular black hole illuminated by various accretion flows 由各种吸积流照亮的内部极端规则黑洞的观测外观

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-09-23 DOI: 10.1140/epjc/s10052-025-14782-x

Dan Zhang, Guoyang Fu, Xi-Jing Wang, Qiyuan Pan, Xiao-Mei Kuang, Jian-Pin Wu

引用次数: 0