The European Physical Journal C最新文献_第3页

The bosonic string spectrum and the explicit states up to level 10 from the lightcone and the chaotic behavior of certain string amplitudes

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-02 DOI: 10.1140/epjc/s10052-025-13955-y

Igor Pesando

{"title":"The bosonic string spectrum and the explicit states up to level 10 from the lightcone and the chaotic behavior of certain string amplitudes","authors":"Igor Pesando","doi":"10.1140/epjc/s10052-025-13955-y","DOIUrl":"10.1140/epjc/s10052-025-13955-y","url":null,"abstract":"<div>We compute the irreps and their multiplicities of bosonic string spectrum up to level 10 and we give explicitly the on shell top level lightcone states which make the irreps. For the irreps up to three indexes and all the totally antisymmetric ones we give the general recipe and the full irreps. It turns out that lightcone is quite efficient in building these low indexes irreps once the top level states are known. For scalars and vectors we compute the multiplicity up to level 22 and 19 respectively. The first scalar at odd level appears at level 11. For the bosonic string in non critical dimensions we argue that at level N there are always states transforming as tensors with (sge frac{1}{2} N) indices. Only in critical dimensions there are states with (sle frac{1}{2} N). Looking at the explicit coefficients of the combinations needed to make the irreps from the lightcone states we trace the origin of the chaotic behavior of certain cubic amplitudes considered in literature to the extremely precise and sensitive mixtures of states. For example the vectors at level (N=19) are a linear combinations of states and when the coefficients are normalized to be integer some of them have more than 1200 figures.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-13955-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749129","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

Probing light scalars and vector-like quarks at the high-luminosity LHC 在高亮度大型强子对撞机上探测轻标量和类矢量夸克

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-02 DOI: 10.1140/epjc/s10052-025-14085-1

U. S. Qureshi, A. Gurrola, A. Flórez, C. Rodriguez

{"title":"Probing light scalars and vector-like quarks at the high-luminosity LHC","authors":"U. S. Qureshi, A. Gurrola, A. Flórez, C. Rodriguez","doi":"10.1140/epjc/s10052-025-14085-1","DOIUrl":"10.1140/epjc/s10052-025-14085-1","url":null,"abstract":"<div>A model based on a (U(1)_{T^3_R}) extension of the Standard Model can address the mass hierarchy between generations of fermions, explain thermal dark matter abundance, and the muon (g - 2), (R_{(D)}), and (R_{(D^*)}) anomalies. The model contains a light scalar boson (phi ') and a heavy vector-like quark (chi _textrm{u}) that can be probed at CERN’s large hadron collider (LHC). We perform a phenomenology study on the production of (phi ') and ({chi }_u) particles from proton–proton ((textrm{pp})) collisions at the LHC at (sqrt{s}=13.6) TeV, primarily through (g{-g}) and (t{-chi _textrm{u}}) fusion. We work under a simplified model approach and directly take the (chi _textrm{u}) and (phi ') masses as free parameters. We perform a phenomenological analysis considering (chi _textrm{u}) final states to b-quarks, muons, and neutrinos, and (phi ') decays to (mu ^+mu ^-). A machine learning algorithm is used to maximize the signal sensitivity, considering an integrated luminosity of 3000 (text {fb}^{-1}). The proposed methodology can be a key mode for discovery over a large mass range, including low masses, traditionally considered difficult due to experimental constraints.\u0000\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14085-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761724","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

Transport phenomena and KSS bound in quantum-corrected AdS black holes

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-01 DOI: 10.1140/epjc/s10052-025-14103-2

Behnam Pourhassan, İzzet Sakallı

{"title":"Transport phenomena and KSS bound in quantum-corrected AdS black holes","authors":"Behnam Pourhassan, İzzet Sakallı","doi":"10.1140/epjc/s10052-025-14103-2","DOIUrl":"10.1140/epjc/s10052-025-14103-2","url":null,"abstract":"<div>In this paper, we study quantum effects on transport properties of charged anti-de Sitter (AdS) black holes, focusing on non-perturbative corrections to the shear viscosity-to-entropy ratio. We consider exponential corrections to both the entropy and transport coefficients, examining their impact on the Kovtun–Son–Starinets (KSS) bound. Through detailed analysis, we demonstrate that quantum corrections significantly modify transport phenomena, particularly in the small-horizon-radius regime. We explore three scenarios: unmodified shear viscosity with quantum-corrected entropy, quantum corrections to both quantities, and preservation of the universal ratio. Our results show that electrical conductivity, bulk viscosity, and thermal conductivity receive substantial modifications from quantum effects while maintaining consistency with established transport laws. The analysis reveals that for the positive correction coefficient, the KSS bound can be violated, while for the negative correction coefficient, it remains valid. We demonstrate these effects through numerical analysis and graphical representations, providing insight into quantum transport phenomena in strongly coupled systems.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14103-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749097","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

Bound states of a fermion-dyon system

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-01 DOI: 10.1140/epjc/s10052-025-14073-5

A. Yu. Loginov

引用次数: 0

Scalar dark matter production through the bubble expansion mechanism: the role of the Lorentz factor and non-renormalizable interactions

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-01 DOI: 10.1140/epjc/s10052-025-14064-6

Jose A. R. Cembranos, Jesús Luque, Javier Rubio

{"title":"Scalar dark matter production through the bubble expansion mechanism: the role of the Lorentz factor and non-renormalizable interactions","authors":"Jose A. R. Cembranos, Jesús Luque, Javier Rubio","doi":"10.1140/epjc/s10052-025-14064-6","DOIUrl":"10.1140/epjc/s10052-025-14064-6","url":null,"abstract":"<div>We consider a Bubble Expansion mechanism for the production of scalar dark matter during a first-order phase transition in the very early Universe. Seeking for a dark matter energy density in agreement with observations, we study different renormalizable and non-renormalizable interactions between the dark matter species and the field undergoing the transition, considering all possible regimes for the Lorentz boost factor associated with the motion of the bubble wall. By employing a combination of analytical and numerical techniques, we demonstrate that sufficient dark matter production is achievable even in the previously unexplored low-velocity bubble expansion regime, enlarging the parameter space and possibilities of the scenario. Notably, for the non-renormalizable interactions it is found that the produced dark matter abundances exhibit a similar qualitative behavior to the renormalizable case, even for low Lorentz boost factors. Furthermore, for a transition around the electroweak scale, the associated gravitational wave spectrum is within the reach of future detectors. \u0000\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14064-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749099","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

Recoil electron polarization-dependent T-odd correlations in neutrino elastic scattering on polarized electron target

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-01 DOI: 10.1140/epjc/s10052-025-14084-2

Arkadiusz Błaut, Wiesław Sobków

{"title":"Recoil electron polarization-dependent T-odd correlations in neutrino elastic scattering on polarized electron target","authors":"Arkadiusz Błaut, Wiesław Sobków","doi":"10.1140/epjc/s10052-025-14084-2","DOIUrl":"10.1140/epjc/s10052-025-14084-2","url":null,"abstract":"<div>Possible symmetry breaking tests with respect to the time inversion in the elastic scattering of neutrinos on polarized electrons are considered, assuming that the incoming neutrino beam is either longitudinally or transversely polarized, and both momentum and polarization of recoil electrons are observed. In the process, in addition to the standard interaction, the exotic scalar, pseudoscalar and tensor interactions can participate. Due to the nonstandard interactions, different types of triple T-odd products in the cross section may appear. We consider several experiments in which mixed products built of the recoil electron polarization and two other vector quantities (incoming neutrino momentum, its polarization, polarization of the electron target and outgoing electron momentum) can be identified. Observations of the T-odd correlations may indicate noninvariance under time reversal as well as the presence of exotic interactions. A complete analysis of the problem requires a precise determination of the possible contributions from the interactions mimicking the genuine violation of time reversal symmetry, e.g. final state interactions.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14084-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749034","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

New physics effects with right-handed neutrinos in semileptonic decay (B_c^+ rightarrow B_s mu ^+ nu _{mu })

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-01 DOI: 10.1140/epjc/s10052-025-14050-y

Priyanka Boora, Dinesh Kumar, Kavita Lalwani

引用次数: 0

Estimation of ( H_0 ) and ( r_d ) in the (omega (z)) parameterization within Einstein and Horava–Lifshitz gravity using DESI-Y1 and SDSS-IV

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-03-31 DOI: 10.1140/epjc/s10052-025-14056-6

Ujjal Debnath, Himanshu Chaudhary, Niyaz Uddin Molla, S. K. J. Pacif, G. Mustafa

{"title":"Estimation of ( H_0 ) and ( r_d ) in the (omega (z)) parameterization within Einstein and Horava–Lifshitz gravity using DESI-Y1 and SDSS-IV","authors":"Ujjal Debnath, Himanshu Chaudhary, Niyaz Uddin Molla, S. K. J. Pacif, G. Mustafa","doi":"10.1140/epjc/s10052-025-14056-6","DOIUrl":"10.1140/epjc/s10052-025-14056-6","url":null,"abstract":"<div>We propose a novel dynamical dark energy model within the frameworks of Einstein gravity and Horava–Lifshitz gravity, utilizing the DCMPM parametrization of the dark energy equation of state to derive the Hubble parameter. We keep ( r_d ) as a free parameter, and use different cosmological datasets such as cosmic chronometer measurements, Type Ia Supernovae observations, and Baryon Acoustic Oscillation data from DESI Y1 and SDSS-IV to extract the posterior distributions of each model parameters. Furthermore, we investigate the evolution of the Universe using various cosmographic parameters and conduct diagnostic analyses, including the statefinder and ( O_m ) diagnostics. Using various statistical metrics, we compare both models against the standard (Lambda )CDM model and find that all are well-supported by current data. Notably, the DCMPM parameterization within Einstein gravity emerges as a promising extension to the standard (Lambda )CDM framework.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 3","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14056-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740820","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

Investigating the glueball-like particle X(2370) in B meson decays

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-03-31 DOI: 10.1140/epjc/s10052-025-13874-y

Xiao-Tong Li, Guang-Yu Wang, Qi-An Zhang

{"title":"Investigating the glueball-like particle X(2370) in B meson decays","authors":"Xiao-Tong Li, Guang-Yu Wang, Qi-An Zhang","doi":"10.1140/epjc/s10052-025-13874-y","DOIUrl":"10.1140/epjc/s10052-025-13874-y","url":null,"abstract":"<div>Based on the collected data on (J/psi rightarrow gamma K_S^0K_S^0eta '), the Beijing Spectrometer (BESIII) experiment has conducted an analysis of the mass and spin parity of the X(2370) particle. The findings areconsistent with the characteristics expected of the lightest pseudoscalar glueball. We point out that further exploration of this particle’s nature can be pursued through investigations of heavy bottom meson decays. Assuming the identity of X(2370) as a pseudoscalar glueball, we compute the form factors for (Brightarrow X(2370)) transitions in the factorization approach. With these results, the estimated branching fractions for semileptonic B decays into X(2370) can reach the order of (10^{-6}) and those for nonleptonic decays can reach the order (10^{-8}). These results suggest that decays of B mesons into X(2370) are detectable at experimental facilities like Belle-II. Future experimental endeavors hold promise in expanding our understanding of glueball physics, contributing to the ongoing exploration of this intriguing particle.</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 3","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-13874-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740819","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

Interplay of intrinsic motion of partons and soft gluon emissions in Drell–Yan production studied with PYTHIA

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-03-30 DOI: 10.1140/epjc/s10052-025-14066-4

I. Bubanja, H. Jung, N. Raičević, S. Taheri Monfared

{"title":"Interplay of intrinsic motion of partons and soft gluon emissions in Drell–Yan production studied with PYTHIA","authors":"I. Bubanja, H. Jung, N. Raičević, S. Taheri Monfared","doi":"10.1140/epjc/s10052-025-14066-4","DOIUrl":"10.1140/epjc/s10052-025-14066-4","url":null,"abstract":"<div>Understanding the intrinsic transverse momentum (intrinsic-(k_textrm{T})) of partons within colliding hadrons, typically modeled with a Gaussian distribution characterized by a specific width (the intrinsic-(k_textrm{T})width), has been an extremely challenging issue. This difficulty arises because event generators like Pythia8 require an intrinsic-(k_textrm{T}) width that unexpectedly varies with collision energy, reaching unphysical values at high energies. This paper investigates the underlying physics behind this energy dependence in Pythia8, revealing that it arises from an interplay between two non-perturbative processes: the internal transverse motion of partons and non-perturbative soft gluon emissions. These contributions are most constrained in the production of Drell–Yan pairs with very low transverse momentum, where soft gluon effects become increasingly prominent with rising collision energy-contrary to initial expectations. Through a detailed analysis of the Sudakov form factor and its influence on intrinsic-(k_textrm{T}) width, we clarify the observed energy scaling behavior in Pythia8, providing insight into a longstanding issue in parton shower modeling.\u0000\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 3","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14066-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740774","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