The European Physical Journal C最新文献_第2页

Chaos of charged particles near a renormalized group improved Kerr black hole in an external magnetic field 外加磁场中重整化群附近带电粒子的混沌改进了克尔黑洞

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-09 DOI: 10.1140/epjc/s10052-025-14853-z

Junjie Lu, Xin Wu

{"title":"Chaos of charged particles near a renormalized group improved Kerr black hole in an external magnetic field","authors":"Junjie Lu, Xin Wu","doi":"10.1140/epjc/s10052-025-14853-z","DOIUrl":"10.1140/epjc/s10052-025-14853-z","url":null,"abstract":"<div>In a quantum theory of gravity, a renormalization group improved Kerr metric is obtained from the Kerr metric, where the Newton gravitational constant is modified as a function of the radial distance. The motion of neutral test particles in this metric is integrable. However, the dynamics of charged test particles is nonintegrable when an external asymptotically homogeneous magnetic field exists in the vicinity of the black hole. The transition from regular dynamics to chaotic dynamics is numerically traced as one or two dynamical parameters vary. From a statistical point of view, the strength of chaos is typically enhanced as both the particle energy and the magnetic field increase, but it is weakened with increasing the particle angular momentum and the black hole spin. In particular, an increase of the quantum corrected parameter weakens the extent of chaos. This is because the running Newton gravity constant effectively weakens the central gravitational attraction and results in decreasing sensitivity to initial conditions.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14853-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256135","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

Decay of Nambu–Goto cosmic string loops via coupling to a massive Kalb–Ramond field 南布-后陀宇宙弦环与大质量卡尔布-雷蒙场耦合的衰减

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-09 DOI: 10.1140/epjc/s10052-025-14851-1

Ivan Rybak

引用次数: 0

Pentaquarks (P_c) in a dynamical coupled-channel approach of (gamma p rightarrow J/psi p) reaction (gamma p rightarrow J/psi p)反应动力学耦合通道方法中的五夸克(P_c)

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-09 DOI: 10.1140/epjc/s10052-025-14845-z

Xu Zhang

{"title":"Pentaquarks (P_c) in a dynamical coupled-channel approach of (gamma p rightarrow J/psi p) reaction","authors":"Xu Zhang","doi":"10.1140/epjc/s10052-025-14845-z","DOIUrl":"10.1140/epjc/s10052-025-14845-z","url":null,"abstract":"<div>We construct a dynamical coupled-channel approach to photon-induced (J/psi ) production to search for the trace of the pentaquarks (P_c.) In this approach, the considered open-charm intermediate states are (Lambda _c bar{D}^{(*)}) and (Sigma _c bar{D}^{(*)}.) Scattering amplitude involving (Lambda _c bar{D}^{(*)},) (Sigma _c bar{D}^{(*)}) and (J/psi p) interactions is calculated from solving a set of coupled-channel integral equations. The coupled-channel interaction potentials are generated from one-boson-exchange. The pentaquarks (P_c) are dynamically generated from the coupled-channel interactions. Moreover, the background contributions to the (P_c) signals are assumed to be the Pomeron exchange and (sigma ) exchange. We analyze the total and differential cross sections of (J/psi ) photoproduction measured by the GlueX and (J/psi )-007 experiments. It is found that both (sigma ) exchange and open-charm state rescattering have contributions in describing the total and differential cross section. The total cross section gets enhanced due to the open-charm state rescattering in the pentaquark production regions, and is of order 1 nb or smaller.</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14845-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256453","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

Thermodynamic analysis and shadow bound of black holes surrounded by a dark matter halo 被暗物质晕包围的黑洞的热力学分析和阴影边界

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-08 DOI: 10.1140/epjc/s10052-025-14861-z

Yun Soo Myung

引用次数: 0

The characteristics of circular motion and quasiperiodic oscillations around accelerating black hole 加速黑洞周围圆周运动和准周期振荡的特性

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-08 DOI: 10.1140/epjc/s10052-025-14857-9

Tao-Tao Sui, Xin-Yang Wang

{"title":"The characteristics of circular motion and quasiperiodic oscillations around accelerating black hole","authors":"Tao-Tao Sui, Xin-Yang Wang","doi":"10.1140/epjc/s10052-025-14857-9","DOIUrl":"10.1140/epjc/s10052-025-14857-9","url":null,"abstract":"<div>This study explores the motion of massive test particles and associated quasi-periodic oscillations (QPOs) around an accelerating black hole. The acceleration factor A suppresses the radial effective potential (V_{text {eff}}), thereby lowering the energy ({mathcal {E}}) and angular momentum ({mathcal {L}}) required for stable circular orbits. Stability demands (partial _r^2 V_{text {eff}} ge 0), setting an upper bound AM (le 0.0161). As A increases, the innermost stable circular orbit (ISCO) radius grows, while ({mathcal {L}}{text {ISCO}}) and ({mathcal {E}}{text {ISCO}}) decrease. Radiative efficiency (epsilon ) rises with A, peaking at (6.9%). Fundamental frequencies show that A accelerates the decay of the Keplerian (Omega _{phi }) and vertical (Omega _{theta }) frequencies, while suppressing the radial frequency E. The divergence between (Omega _{theta }) and (Omega _{phi }) increases with A, differing from spherical black hole behavior. Using the RP, ER3, ER4, and WD QPO models, the WD model predicts the highest frequencies. ER4’s resonant radius remains fixed across frequency ratios, unlike ER3. Although A suppresses twin-peak QPO frequencies, it enhances the nodal precession frequency (nu _{text {nod}}). Fitting observational data from GRO J1655−40 and XTE J1859+226 and applying the TOV limit, the ER4 model uniquely fits GRO J1655−40 with ((10^3A, M, r/M) approx (4.31, 3.43 M_odot , 8.08)). For XTE J1859+226, three models yield (10^3A approx 1.4), excluding ER3, suggesting stronger acceleration in GRO J1655−40.\u0000\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14857-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256606","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

Multi-messenger and cosmological constraints on dark matter through two-fluid neutron star modeling 通过双流体中子星模型对暗物质的多信使和宇宙学约束

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-08 DOI: 10.1140/epjc/s10052-025-14849-9

Ankit Kumar, Sudhakantha Girmohanta, Hajime Sotani

{"title":"Multi-messenger and cosmological constraints on dark matter through two-fluid neutron star modeling","authors":"Ankit Kumar, Sudhakantha Girmohanta, Hajime Sotani","doi":"10.1140/epjc/s10052-025-14849-9","DOIUrl":"10.1140/epjc/s10052-025-14849-9","url":null,"abstract":"<div>In this study, we investigate the impact of dark matter (DM) on neutron stars (NSs) using a two-fluid formalism that treats nuclear matter (NM) and DM as gravitationally coupled components. Employing NM equations of state spanning a wide range of stiffness and a self-interacting asymmetric fermionic DM framework, we explore the emergence of DM core- and halo-dominated structures and their observational implications. Constraints from gravitational waves (GW170817), NICER X-ray measurements (PSR J0030+0451), and pulsar mass limits (PSR J0740+6620) delineate a consistent parameter space for DM properties derived from these multi-messenger observations. DM halo-dominated configurations, while consistent with PSR J0740+6620’s mass limits and NICER’s radius measurements for PSR J0030+0451, are ruled out by the tidal deformability bounds inferred from the GW170817 event. Consequently, the combined limits inferred from the observational data of GW170817, PSR J0030+0451, and PSR J0740+6620 support the plausibility of DM core-dominated configurations. Constraints on the DM self-interaction strength from galaxy cluster dynamics further refine the DM parameter space permitted by NS observations. This work bridges multi-messenger astrophysics and cosmology, providing insights into DM interactions and their implications for NS structure, evolution, and observational signatures.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14849-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256642","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

Semiclassical causal geodesics: Minkowski spacetime case 半经典因果测地线：闵可夫斯基时空情形

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-08 DOI: 10.1140/epjc/s10052-025-14804-8

Adam Cieślik, Andrzej Góźdź, Patryk Mach, Aleksandra Pȩdrak, Włodzimierz Piechocki

{"title":"Semiclassical causal geodesics: Minkowski spacetime case","authors":"Adam Cieślik, Andrzej Góźdź, Patryk Mach, Aleksandra Pȩdrak, Włodzimierz Piechocki","doi":"10.1140/epjc/s10052-025-14804-8","DOIUrl":"10.1140/epjc/s10052-025-14804-8","url":null,"abstract":"<div>We use an integral quantization model based on the Heisenberg–Weyl group to describe the motion of a spinless particle in the Minkowski background spacetime. This work is a sequel to a previous paper, devoted to mathematical aspects of our model: construction of the space of coherent states and properties of elementary observables. We compute transition amplitudes corresponding to the free motion of a particle between two coherent states. These amplitudes are then used to model quantum random walks of free relativistic particles. Our quantization scheme allows us to recover interference patterns occurring in a standard double-slit experiment, known from the classical approach. This result is obtained by modeling the slits in terms of eigenstates of the position operator and computing transition amplitudes between position and coherent states. We design our model in a way which allows for a future generalization to a semiclassical quantization of the geodesic motion in curved spacetimes.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14804-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256607","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

The lower bound on the orbital period of Kerr–Newman black holes 克尔-纽曼黑洞轨道周期的下界

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-08 DOI: 10.1140/epjc/s10052-025-14828-0

Yan Peng

引用次数: 0

Revisiting the (Lambda _c^+rightarrow bar{K}^0eta p) reaction: the role of (N^*(1535),) (N^*(1650)) and (Sigma (1620)) 回顾(Lambda _c^+rightarrow bar{K}^0eta p)的反应：(N^*(1535),)(N^*(1650))和的作用 (Sigma (1620))

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-08 DOI: 10.1140/epjc/s10052-025-14870-y

Jing Song, Melahat Bayar, Yi-Yao Li, Eulogio Oset

{"title":"Revisiting the (Lambda _c^+rightarrow bar{K}^0eta p) reaction: the role of (N^*(1535),) (N^*(1650)) and (Sigma (1620))","authors":"Jing Song, Melahat Bayar, Yi-Yao Li, Eulogio Oset","doi":"10.1140/epjc/s10052-025-14870-y","DOIUrl":"10.1140/epjc/s10052-025-14870-y","url":null,"abstract":"<div>We perform a theoretical study of the weak decay (Lambda _c^+ rightarrow bar{K}^0 eta p) using a coupled-channel chiral unitary approach that incorporates both pseudoscalar-baryon and vector-baryon interactions. Our framework includes contributions from both internal and external weak emission mechanisms, as well as strong final state interactions. We assume that the (N^*(1535)) and (N^*(1650)) resonances are dynamically generated through meson-baryon scattering and they appear as distinct structures in the (eta p) invariant mass distributions. A clear peak also appears in the (bar{K}^0 p) invariant mass distribution around 1620 MeV, associated with the dynamically generated (Sigma (1620)) resonance. Notably, this work provides the first theoretical description of the simultaneous observation of these two related (N^*) resonances in the same meson-baryon final state. Our results highlight the crucial role of final state interaction and the interplay between different weak decay topologies in shaping the resonance patterns. These findings offer new insights into the nature of nucleon excitations and support the interpretation of (N^*(1535)) and (N^*(1650)) as dynamically generated states. Moreover, the identification of the (Sigma (1620)) further supports the picture of hadronic molecular structures emerging from meson-baryon interactions in the non-perturbative QCD regime.\u0000</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14870-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256643","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

Hunting primordial black hole dark matter in the Lyman-(alpha ) forest 在莱曼- (alpha )森林中寻找原始黑洞暗物质

IF 4.8 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-10-08 DOI: 10.1140/epjc/s10052-025-14827-1

Akash Kumar Saha, Abhijeet Singh, Priyank Parashari, Ranjan Laha

{"title":"Hunting primordial black hole dark matter in the Lyman-(alpha ) forest","authors":"Akash Kumar Saha, Abhijeet Singh, Priyank Parashari, Ranjan Laha","doi":"10.1140/epjc/s10052-025-14827-1","DOIUrl":"10.1140/epjc/s10052-025-14827-1","url":null,"abstract":"<div>A very pressing question in contemporary physics is the identity of Dark Matter (DM). Primordial Black Holes (PBHs) are one of the most well-motivated DM candidates. Light PBHs have been constrained by either the non-detection of their Hawking radiation itself, or by the non-observation of any measurable effects of this radiation on astrophysical and cosmological observables. We constrain the PBH contribution to the DM density by non-detection of their Hawking radiation’s effect on the intergalactic medium (IGM) temperature evolution. We use the latest deductions of IGM temperature from Lyman-(alpha ) forest observations. We put constraints on the fraction of DM as PBHs with masses (5 times 10^{15}) g–(10^{17}) g, separately for spinning and non-spinning BHs. We derive constraints by dealing with the heating effects of the astrophysical reionization sources on the IGM in two ways. In one way, we completely neglect this heating due to astrophysical sources, thus giving us weaker constraints, but completely robust to the reionization history of the universe. In the second way, we utilise some modelling of the ionization and temperature history, and use it to derive more stringent constraints. We find that for non-spinning PBHs of mass (10^{16}) g, the current measurements can constrain the PBH-density to be (lesssim ) 0.1% of the total DM. We find that these constraints are competitive, and hence provide a new observable to probe the nature of PBH DM. The systematics affecting Lyman-(alpha ) forest measurements are different from other constraining observations, and thus this is a complementary probe.</div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14827-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256110","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