物理最新文献

{"title":"Holographic QCD running coupling for heavy quarks in strong magnetic field","authors":"Irina Ya. Aref’eva,&nbsp;Ali Hajilou,&nbsp;Alexander Nikolaev,&nbsp;Pavel Slepov","doi":"10.1140/epjc/s10052-025-14885-5","DOIUrl":"10.1140/epjc/s10052-025-14885-5","url":null,"abstract":"<div><p>We investigate the influence of a magnetic field on the running coupling constant for a heavy-quark model in a bottom-up holographic approach. To achieve this, we employ a magnetized Einstein–Maxwell–Dilaton background that captures the essential features of heavy quark dynamics. Similar to the light-quark model, the running coupling <span>(alpha )</span> for heavy quarks decreases in the presence of a strong external magnetic field at fixed temperature and chemical potential. The key distinction between the light and heavy quark models lies in the locations of their respective phase transitions. However, near the 1st order phase transitions, the behavior of <span>(alpha )</span> is analogous for both cases: <span>(alpha )</span> exhibits jumps that depend on temperature, chemical potential, and magnetic field strength.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14885-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316149","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}

{"title":"Localization of q-form field on squared curvature gravity domain wall brane coupling with gravity and background scalar","authors":"Xin-Nuo Zhang,&nbsp;Heng Guo,&nbsp;Yong-Tao Lu","doi":"10.1140/epjc/s10052-025-14900-9","DOIUrl":"10.1140/epjc/s10052-025-14900-9","url":null,"abstract":"<div><p>Unlike the duality in four-dimensional spacetime, where the <i>q</i>-form fields corresponds to the scalar fields or the vector fields, in higher dimensional spacetime, they denote new types of particles. In this paper, we investigate the localization of the KK modes of the <i>q</i>-form fields in a five dimensional brane world. We introduce the coupling between the <i>q</i>-form fields and both the gravity and the background scalar field. This consideration enables the localization of the <i>q</i>-form fields on the five-dimensional RS-2 thick brane, leading to the derivation of zero modes, Schrödinger-like equations, and a four-dimensional effective action. We suggest a new function <span>(F(R,varphi ))</span> to stand for the coupling of the <i>q</i>-form field with gravity and background scalar fields. Our analysis highlights the significance of the parameters <span>(text{ C}_2)</span> and <span>(displaystyle t)</span> in the localization processes.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14900-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316148","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}

{"title":"Macroscopic states in Bose–Einstein condensate dark matter model with axionlike interaction","authors":"Andriy Nazarenko","doi":"10.1140/epjc/s10052-025-14893-5","DOIUrl":"10.1140/epjc/s10052-025-14893-5","url":null,"abstract":"<div><p>The phase diagrams of ultralight dark matter (DM), modeled as a self-gravitating Bose–Einstein condensate with axionlike interaction, are studied. We classify stable, metastable, and unstable DM states over a wide range of condensate wave function amplitudes. It is shown that the axionlike interaction causes instability and an imaginary speed of sound at low amplitudes, whereas, in a specific high-amplitude band, DM attains a stable state capable of forming a dense solitonic core and suppressing quantum fluctuations in the surrounding galactic DM halo. These findings are corroborated by evaluating thermodynamic functions for DM in the dwarf galaxy NGC 2366 and its hypothetical analogs with different core-to-halo mass ratios. Distinct DM phase compositions respond differently to fluctuation-induced partial pressure, resulting in a first-order phase transition in a certain range of an interaction parameter. While the DM properties in NGC 2366 lie within the supercritical regime, the phase transition nonetheless provides a thermodynamic marker separating stable from unstable DM configurations. Once a dense core forms – reaching a threshold of about 12% of the total mass – the enhanced gravitation stabilizes the DM halo against fluctuations, while the internal pressure ensures core stability. In particular, we find that NGC 2366’s dense DM comprises roughly 19% of the DM mass while occupying only 4.7% of its total volume.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14893-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316146","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}

{"title":"Lyapunov exponents, phase transitions, and Chaos bound of ModMax AdS black holes","authors":"Gorima Bezboruah,&nbsp;Mozib Bin Awal,&nbsp;Prabwal Phukon","doi":"10.1140/epjc/s10052-025-14920-5","DOIUrl":"10.1140/epjc/s10052-025-14920-5","url":null,"abstract":"<div><p>We study the thermodynamic phase transition of ModMax anti-de Sitter (AdS) black holes using Lyapunov exponents of massless and massive particles in unstable circular orbits. Our results demonstrate that the thermal profile of the Lyapunov exponent serves as an efficient probe of the black hole’s phase structure. We calculate the discontinuity in the Lyapunov exponent across the transition and show that it acts as an order parameter, exhibiting a critical exponent <span>(delta =1/2)</span> in the vicinity of the critical point. Furthermore, we explore the violation of the chaos bound, finding that the bound is violated when the horizon radius falls below a threshold value. We also examine how the ModMax parameter and the particle’s angular momentum modify this threshold, revealing their role in controlling the onset of chaos bound violation.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14920-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316147","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}

{"title":"Overview of national regulatory approaches to assess worker’s exposure to radon in industries involving norm","authors":"R. Trevisi,&nbsp;T. Bituh,&nbsp;A. Canoba,&nbsp;M. Chege,&nbsp;A. Cordelle,&nbsp;D. Chambers,&nbsp;N. Chambers,&nbsp;P. Egidi,&nbsp;R. Gellermann,&nbsp;F. Grandia,&nbsp;J. Hondros,&nbsp;C. Kunze,&nbsp;J. Lee,&nbsp;B. Michalik,&nbsp;F. Otoo,&nbsp;S. Pepin,&nbsp;K. N. Rovenska,&nbsp;R. Sapoi,&nbsp;P. Tchokossa,&nbsp;O. van Dongen","doi":"10.1140/epjp/s13360-025-06837-5","DOIUrl":"10.1140/epjp/s13360-025-06837-5","url":null,"abstract":"<div><p>National regulations address the radiological protection of industrial processes involving Naturally Occurring Radioactive Material (NORM), each with different approach. A collection of information gathered by members of the International Radiation Protection Association task group on “NORM” helps identify key differences in regulatory strategies. The main findings indicate that, while national regulations generally implement the requirements of international standards—and, for EU Member States, the provisions of European Commission directives—and consider ICRP recommendations, the regulatory approaches and protocols for managing worker exposure to radon in workplaces involving NORM vary significantly. In most countries, industrial processes involving NORM are regulated as planned exposure situations, whereas exposure to radon in workplaces is typically managed as an existing exposure situation. When radon doses need to be assessed because requirements for planned exposure situations apply, national regulations often require that these contributions be recorded and treated separately. However, in several countries, the contribution from radon inhalation is explicitly incorporated into the total effective dose assessment. In certain cases, the calculation specifically accounts only for the radon exposure attributable to the handling of NORM, excluding background or unrelated sources. The methodology for estimating radon doses can vary significantly between countries. There is a lack of harmonisation in the physical quantities used for assessment, as well as in the values of dose conversion factors.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Production of Δ0 resonances in p+12C collisions at 9.9 GeV/c","authors":"Kosim Olimov,&nbsp;Kadyr G. Gulamov,&nbsp;Akbar I. Suvanov,&nbsp;Khusniddin K. Olimov","doi":"10.1140/epjp/s13360-025-06934-5","DOIUrl":"10.1140/epjp/s13360-025-06934-5","url":null,"abstract":"<div><p>The new experimental data on the inclusive reaction <i>p</i>+¹²C → ∆⁰ + X at an incident proton momentum of 9.9 GeV/<i>c</i> and various characteristics of the ∆⁰ resonances produced in <i>p</i>+¹²C collisions at projectile proton momentum of 4.2 and 9.9 GeV/<i>c</i> have been presented. The average mass and width of the mass distribution of the ∆⁰ resonances have proved to be independent of the primary energy of incident protons. The mass width of the ∆⁰ resonances produced in the target (¹²C) nucleus fragmentation region has been found to be almost half of the mass width of the ∆⁰ resonances in free hadron-nucleon collisions. The average number per one collision event of the ∆⁰ resonances produced in <i>p</i>+¹²C collisions at 9.9 GeV/<i>c</i> turned out to be about 2.4 times greater than that in <i>p</i>+¹²C collisions at 4.2 GeV/<i>c</i>. We have obtained that the hypothesis of the limiting fragmentation is not fulfilled for the ∆⁰ resonances in the inclusive reaction <i>p</i>+¹²C → ∆⁰ + X in the range of kinetic energy of the incident projectile protons from 3.37 to 9 GeV, corresponding to the momentum interval of incident protons from 4.2 to 9.9 GeV/<i>c</i>. The results of present analysis indicate that formation of the ∆⁰ resonance in the region of fragmentation of the target (¹²C) nucleus in <i>p</i>+¹²C collisions at 9.9 GeV/<i>c</i> occurs predominantly via excitation of one of the target (¹²C) neutrons to a ∆⁰ resonance, which then decays promptly into proton and <i>π</i>^‒ meson.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamical systems approach and cosmological attractors in newer general relativity","authors":"Manuel Hohmann,&nbsp;Ulbossyn Ualikhanova","doi":"10.1140/epjc/s10052-025-14865-9","DOIUrl":"10.1140/epjc/s10052-025-14865-9","url":null,"abstract":"<div><p>We study the cosmological dynamics of a class of symmetric teleparallel gravity theories known as “newer general relativity” using the methods of dynamical systems, restricted to the case of vacuum solutions with a spatially flat Friedmann–Lemaître–Robertson–Walker metric. For the most general class of theories, we study generic properties of the solutions, in particular their fixed points, asymptotic behavior and effective dark energy. We then apply this approach to two phenomenologically motivated subclasses of theories, which we study in full detail. For these theories, we derive the complete space of solutions and cosmological attractors, which we display in a number of phase diagram. Depending on the particular theory at hand, we find different possible scenarios, including a turnaround followed by a big crunch, a big rip and an eternally expanding universe whose Hubble parameter asymptotically approaches zero. It turns that this different behavior can be explained by the effective dark energy barotropic index, which shows either phantom or non-phantom behavior, depending on the theory, but does not change dynamically between these two possibilities.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14865-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316591","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}

{"title":"Bifurcation analysis and Turing pattern formation on multiplex networks of ecological model with trade-off dynamics","authors":"Masoom Bhargava,&nbsp;Balram Dubey","doi":"10.1140/epjp/s13360-025-06951-4","DOIUrl":"10.1140/epjp/s13360-025-06951-4","url":null,"abstract":"<div><p>Ecological trade-offs occur when organisms balance conflicting demands, such as survival and reproduction. Predators may risk injury or death when pursuing dangerous prey, affecting their survival. Similarly, prey must balance reproductive efforts against safety, while predators must weigh food acquisition against the risk of harm. In order to represent prey collective defense, we present a ecological model in this study that includes prey growth affected by fear and a Monod-Haldane functional response. We explore how group defense influences prey trade-off dynamics and introduce a predator death function to represent losses due to dangerous prey encounters. The model reveals complex dynamics, including bistability and several bifurcations: transcritical, saddle-node, Hopf, Bogdanov–Takens, Bautin, homoclinic, and limit cycle bifurcations. Our results indicate that high amount of group defense can lead to predator extinction, highlighting the trade-off between food acquisition and safety. We further extend the model to include cross-diffusion, accounting for species-specific movement patterns. We theoretically derive Turing conditions for both continuous and multiplex domains, demonstrating how cross-diffusion and network topology can destabilize homogeneous steady states, leading to diverse Turing patterns. Our findings reveal that over time prey can drive predator extinction, emphasizing the trade-off between food acquisition and safety in predator–prey systems. Additionally, we observe that variations in the average degree of the Lattice can significantly influence the emergence of Turing patterns and the spatial distribution of species.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strategic research agenda and roadmaps for radiation protection metrology","authors":"João Alves,&nbsp;Margarida Caldeira,&nbsp;Ana Fernandes,&nbsp;Steffen Ketelhut,&nbsp;Behnam Khanbabaee,&nbsp;Oliver Hupe,&nbsp;Hayo Zutz,&nbsp;Annette Röttger,&nbsp;Teemu Siiskonen,&nbsp;Reetta Nylund,&nbsp;Christelle Adam-Guillermin,&nbsp;Miloš Živanović,&nbsp;Attila Veres,&nbsp;Vladimir Sochor,&nbsp;Mihail-Razvan Ioan,&nbsp;Amra Šabeta,&nbsp;Robert Bernat,&nbsp;Steven Bell,&nbsp;Britt Wens,&nbsp;Denis Glavič-Cindro,&nbsp;Linda Persson","doi":"10.1140/epjp/s13360-025-06898-6","DOIUrl":"10.1140/epjp/s13360-025-06898-6","url":null,"abstract":"<div><p>EURAMET EMPIR 19NET03 <i>supportBSS</i> project entitled <i>Support for a European Metrology Network (EMN) on reliable radiation protection regulation</i>, started in June 2020 and completed in May 2024. One of the tasks of the <i>supportBSS</i> project was the preparation of a Strategic Research Agenda (SRA) based on the identified metrology needs to support the European legislation and regulation in Radiation Protection, and of two Roadmaps for metrology services and capabilities, one under the European Council Directive 2013/59/EURATOM and the other under the EURATOM Treaty. The preparation of the SRA began with a comprehensive literature review including the analysis of the SRAs from the MEENAS Radiation Protection platforms and of strategic documents from other relevant organizations such as IAEA, BIPM-CCRI, HERCA, EURAMET, among others. Information was also collected from the stakeholders at different stages of the project, through organized workshops and a targeted questionnaire, which included specific sections for metrology laboratories and for stakeholders from the different fields of activity. This paper presents the first SRA and Roadmaps developed as key outputs of the <i>supportBSS</i> project, presented to EURAMET as deliverables 4 and 5 at the closure of the project. Taking into account the ongoing technological developments in the field, as well as the fact that EURAMET may use the information collected at its own discretion, it is anticipated the European Metrology Network for Radiation Protection will need to periodically revise and update these documents in the near future.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06898-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"A realistic photon spectra in polarized (gamma gamma ) processes in SANCphot","authors":"Sergey G. Bondarenko,&nbsp;Aidos Issadykov,&nbsp;Lidia V. Kalinovskaya,&nbsp;Andrey A. Sapronov","doi":"10.1140/epjc/s10052-025-14904-5","DOIUrl":"10.1140/epjc/s10052-025-14904-5","url":null,"abstract":"<div><p>This work presents an approach to improve the precision of polarized photon–photon collisions simulation implemented in the SANCphot package. The basic linear Compton approximation of the incoming photon spectrum is extended to a general energy distribution and a realistic description of circular or linear polarizations as expected to be seen at photon–photon colliders.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14904-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316240","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}