The European Physical Journal Plus最新文献

{"title":"Spin effects on particle creation and evaporation in f(R, T) gravity","authors":"A. A. Araújo Filho,&nbsp;N. Heidari,&nbsp;Francisco S. N. Lobo","doi":"10.1140/epjp/s13360-026-07656-y","DOIUrl":"10.1140/epjp/s13360-026-07656-y","url":null,"abstract":"<div><p>In this work, we study how the spin of particle modes influences particle creation, greybody factors, absorption, and evaporation of a black hole within the framework of modified electrodynamics in <i>f</i>(<i>R</i>, <i>T</i>) gravity, recently proposed in Róis et al. (Phys Rev D 111(12):124044, 2025). All spin sectors-scalar, vector, tensor, and spinorial-are analyzed to obtain the corresponding features. For particle creation, we consider massless bosonic and fermionic perturbations to determine the respective particle densities. Analytical expressions for the greybody factors are derived, with suitable approximations for the tensor and spinorial cases. The absorption cross section is computed numerically, and using the <i>Stefan–Boltzmann</i> law, we estimate the black hole evaporation lifetime. The associated energy and particle emission rates are also discussed, along with the correspondence between quasinormal modes and greybody factors.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-026-07656-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738356","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":"Multimodal manuscript representation: toward an open repository for manuscript research data","authors":"Hans Clausen,&nbsp;Simon Brenner,&nbsp;Manfred Schreiner,&nbsp;Willfried Vetter","doi":"10.1140/epjp/s13360-025-07133-y","DOIUrl":"10.1140/epjp/s13360-025-07133-y","url":null,"abstract":"<div><p>Research on historical manuscripts is increasingly supported by technical disciplines, which are used, for example, to digitally restore degraded text or to analyze the composition of inks, pigments, binders, and the materials constituting the manuscript’s support. The Centre of Image and Material Analysis in Cultural Heritage (CIMA) in Vienna is an inter-university research institution that fosters collaboration between philology and the natural sciences. CIMA has generated a large amount of diverse research data and findings concerning numerous manuscripts. These data exist in various formats and are distributed across different storage media at the participating institutions. This paper describes the conceptual framework and technical implementation of a digital research data repository designed for the long-term preservation and dissemination of CIMA’s large volumes of heterogeneous data. The repository provides the research data related to the examined manuscripts for download and reuse by interested users, in accordance with open-access principles. Furthermore, the diverse data are visualized through a user interface, presenting different research insights derived from a single physical manuscript. This multimodal representation of a manuscript is intended to serve as an accessible starting point for interdisciplinary investigation, data exploration, and teaching.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-07133-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738178","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":"Radiation interaction characteristics and spectroscopic properties of novel produced Ni40Co10Cr10Al10Ti10B5Rx (x = 15; R: Mo, Ta, W, Nb, Gd) alloys for nuclear applications","authors":"Murat Aygun,&nbsp;Zeynep Aygun,&nbsp;Ercan Ercan","doi":"10.1140/epjp/s13360-026-07683-9","DOIUrl":"10.1140/epjp/s13360-026-07683-9","url":null,"abstract":"<div><p>The present study aims to develop five novel Ni-based alloys and systematically evaluate their radiation shielding performance. The elements Ni, Al, Ti, Cr, Co, B, Ta, Mo, Nb, Gd and W were selected for the development of Ni-based alloys with the composition Ni40Co10Cr10Al10Ti10B5Rx (x = 15; R: Mo, Ta, W, Nb, Gd). The attenuation parameters were determined using the Phy-X/PSD software and also compared with literature results. Furthermore, experimental results were obtained using X-ray diffraction, Scanning Electron Microscopy and Energy Dispersive Spectroscopy techniques. X-ray diffraction analysis demonstrates that all alloys crystallize primarily in the FCC structure; secondary phases emerge in dependence of refractory additions. The relationship between the content of Mo, Ta, W, Nb, Gd and the radiation protection capability of the alloys were evaluated. It can be noted that the alloy containing W exhibits superior shielding performance, whereas the alloys containing Nb and Gd show lower shielding capabilities. The findings of this study show that Ni-based alloys have favorable shielding properties for use as shielding materials in nuclear applications.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-026-07683-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738347","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":"Flavour physics beyond the LHC","authors":"Patrick Koppenburg","doi":"10.1140/epjp/s13360-026-07522-x","DOIUrl":"10.1140/epjp/s13360-026-07522-x","url":null,"abstract":"<div><p>The next 20 years will be the golden age of flavour physics, with the operation of the LHCb and Belle II experiments. After that, an <span>(e ^{+}e ^{-})</span> collider could further improve the precision with sizeable <span>(text {Z})</span>, <span>(W ^{+})</span> <span>(W ^{-})</span> and <span>(textrm{t})</span> <span>(overline{{textrm{t}}})</span> runs.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737840","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":"Nonlinear pulsational modes in (kappa)-deformed spherical tripolar dust molecular clouds to structure formation","authors":"Jonmoni Dutta,&nbsp;Ahmed Atteya,&nbsp;Pralay Kumar Karmakar","doi":"10.1140/epjp/s13360-026-07557-0","DOIUrl":"10.1140/epjp/s13360-026-07557-0","url":null,"abstract":"<div><p>The astrophysical mechanism responsible for hierarchical bounded structure formation in diverse cosmic environments has been an active research frontier for decades. In particular, gravitational collapse dynamics in dust molecular clouds (DMCs) plays a central role in star formation processes. In this context, nonlinear analyses incorporating the presence of negative ions and tripolar dust still remain unexplored. We herein develop a theoretical model formalism to study the nonlinear pulsational mode of gravitational collapse (PMGC) dynamics in spherically symmetric astrophysical DMCs. The macroscopic DMC state is presumed to exist in a globally quasi-neutral, hydrostatic, and homogeneous equilibrium. It comprises lighter nonthermal species, such as electrons, positive ions, and negative ions, modeled with the <span>(kappa)</span>-deformed Kaniadakis distribution laws, with heavier dust grains as viscous fluids. The dust thermodynamics is described amid the Larson logatropic barotropic equation of state. Applying the nonlinear Wentzel, Kramers, Brillouin (WKB) perturbation method, we methodically derive a pair of gravitoelectrostatically coupled extended Korteweg-de-Vries (ce-KdV) equations. Numerical analysis reveals the excitation of a conjugational pair-hybrid solitary wave train modal pattern, alongside their diverse multiparametric stability properties. This study further shows that the PMGC dynamics exhibits non-conservative behaviors due to the collective dust-induced coupling effects. This ce-KdV study offers essential insights into the self-gravitational collapse phenomena relevant to early-stage star formation scenarios.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738379","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":"Approximate computation of all eigenvalues using sparse block-low-rank matrices in electronic structure calculations for aggregated molecular systems","authors":"Akihiro Ida,&nbsp;Takeo Hoshi","doi":"10.1140/epjp/s13360-026-07642-4","DOIUrl":"10.1140/epjp/s13360-026-07642-4","url":null,"abstract":"<div><p>In electronic structure calculations (ESCs) to study various properties of materials, it is necessary to calculate all eigenvalues in such a way that their order is known. Therefore, a tridiagonalization method using the repeated block Householder transformation (HT) is generally employed to solve eigenvalue problems for discretized matrices. Although the matrix can be represented as a sparse matrix with high accuracy, it is treated as a dense matrix from the beginning because the sparse matrix is transformed into a dense matrix in a single block HT. The method based on dense matrix arithmetic requires a memory storage of <span>(Oleft({N}^{2}right))</span> and arithmetic operations of <span>(Oleft({N}^{3}right))</span>. In this study, a construction method of sparse BLR matrices for ESCs and a special block HT for the sparse BLR matrices are proposed to reduce them and provide a pre-screening method to search for promising materials by calculating approximately all the eigenvalues of ESCs. The proposed method realizes efficient arithmetic by determining the block size of sparse BLR matrices on the molecular unit under the assumption of an aggregated molecular system. The validity of the proposed method has been investigated for aggregated fullerene (<span>({text{C}}_{60})</span>) molecules. It is confirmed that the accuracy of the band energy and the band gap calculated from the eigenvalues can be controlled by the tolerance <span>({varepsilon }_{H})</span> for the low-rank approximation in the modified special block HT for sparse BLR matrices. Numerical experiments show that the memory complexity of the proposed method is between <span>(Oleft(Nright))</span> and <span>(Oleft({N}^{2}right))</span> depending on the molecular arrangements and the required accuracy. Even when <span>(Oleft({N}^{2}right))</span> memory is required, it is less than a tenth of that required for the conventional method with dense matrices. Moreover, the computational complexity of the proposed method appears to be <span>(O)</span>(<span>({N}^{2})</span>), significantly reduced from <span>(O)</span>(<span>({N}^{3})</span>) of the conventional method.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738241","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":"Measurement-dependent nonlocality in tree tensor networks","authors":"Meng Cui,&nbsp;Jinchuan Hou,&nbsp;Lihua Yang,&nbsp;Xiaofei Qi","doi":"10.1140/epjp/s13360-026-07532-9","DOIUrl":"10.1140/epjp/s13360-026-07532-9","url":null,"abstract":"<div><p>Bell inequalities of local reality and network local reality are established based on the assumption of measurement independence. The violation of Bell’s inequalities witnesses the existence of nonlocal correlations. However, the assumption of measurement independence is contradictory to a fully causal hidden variable theory. In this paper, we focus on measurement-dependent nonlocality in tree tensor networks. We derive corresponding measurement-dependent network locality inequalities, and investigate the degree of measurement independence required for signal-free classical local models to simulate nonlocal correlations under conditions where different parties exhibit measurement dependence. Our research findings indicate that, when both the first and last layers exhibit measurement dependence, the required degree of measurement independence is higher than in the scenario where only the last layer exhibits measurement dependence. This suggests that the former configuration offers greater security for applications in quantum communication. Furthermore, the number of input measurements has a significant impact on the measurement independence required for signal-free classical local models to simulate nonlocal correlations.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738240","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":"Assessment of dosimetric characteristics of sheep tooth enamel using electron paramagnetic resonance technique","authors":"Ghada Bassioni,&nbsp;Nabil El-Faramawy","doi":"10.1140/epjp/s13360-026-07638-0","DOIUrl":"10.1140/epjp/s13360-026-07638-0","url":null,"abstract":"<div><p>The electron paramagnetic resonance (EPR) spectra of six sheep molar teeth were examined as radiation dosimeters. Enamel fragments with a grain size of 80–125 μm were extracted and prepared. Basic parameters such as microwave generator frequency were extensively studied, and it was found that the appropriate frequency was at least 100 GHz or more. The dose response of the enamel fragments was studied using two different gamma sources. The response was found to be linear at low doses up to 39 Gy and then the behavior changed to supralinear at high doses. The study showed the possibility of using sheep teeth as a radiation dosimeter in conditions of radioactive contamination.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738026","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":"Thermal fluctuations and accretion disk of a non-commutative AdS black hole with a global monopole","authors":"Rabia Saleem,&nbsp;Muhammad Israr Aslam,&nbsp;Arshia Anees","doi":"10.1140/epjp/s13360-026-07681-x","DOIUrl":"10.1140/epjp/s13360-026-07681-x","url":null,"abstract":"<div><p>In the present work, we have investigated thermodynamics and shadow images obtained by infalling spherical accretion flow of non-commutative (NC) Anti-de Sitter (AdS) black hole (BH) with global monopole. The relation between temperature <span>(T_{+})</span> and the event horizon <span>(r_{+})</span> interprets that it reaches the highest point for larger radii of BH event horizon <span>(r_{+})</span> when <span>(P&lt;P_{c})</span> (where <i>P</i> is thermodynamical pressure and <span>(P_{c})</span> is the critical pressure). From the analysis of heat capacity <span>(C_{P})</span>, we find that the smaller and larger BHs are showing stable thermal fluctuations, while intermediate BHs depict unstable behavior. We discussed the Gibbs free energy, which indicates that the larger BHs are more thermodynamically stable as compared to smaller ones. We also derive the exact values of critical points and probe the influence of each parameter on <span>(P-V)</span> criticality and observe that the isotherms and slightly consistent with Van der Walls like fluid. Finally, we discussed the optical features of BH shadow images as well as intensities for different values of involved parameters. It is observed that both the size of the BH shadow and the observed intensities change significantly with variations in <span>(theta)</span> and <span>(eta)</span>.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737994","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":"Computational analysis of nonlinear bioheat transfer equation of multilayered brain tissue with porosity during tumor thermal therapy","authors":"Deepak Kumar,&nbsp;Faishal Ansari,&nbsp;Jitendra Singh","doi":"10.1140/epjp/s13360-026-07640-6","DOIUrl":"10.1140/epjp/s13360-026-07640-6","url":null,"abstract":"<div><p>The present model incorporates a bioheat transport framework within multilayered brain tissue, accounting for blood perfusion and thermal conductivity as temperature-dependent variables, while also considering porosity during magnetic fluid hyperthermia. Additionally, the skin’s surface is subjected to a nonlinear boundary condition of heat-flux kind. The treatment’s temperature level is crucial for tumor eradication, which is forecasted by resolving the current model utilizing the Crank–Nicolson scheme. To validate the current scheme, we compared with the Laplace transform solution in specific situation against both types of boundary conditions. The analysis indicates that augmenting the nonlinear thermal conductivity coefficient (<span>(alpha _{2})</span>) and the blood perfusion coefficient (<span>(beta _2)</span>) reduces the temperature profile. Moreover, augmenting the porosity parameter (<span>(mathfrak {e}_i)</span>) substantially reduces tissue temperature. Furthermore, augmenting the magnetic parameters <span>(H_0)</span> and <i>f</i> boosts the heating profile specifically within the tumor. An elevation in the convective heat transfer coefficient (<span>(h_c)</span>) under Robin conditions reduces outer-layer temperatures, whereas an increased ambient temperature (<span>(T_{00})</span>) elevates the boundary temperature. The Neumann condition reduces outer-layer temperatures by increasing heat flux (<span>(q_o)</span>). A comparative investigation demonstrates that the nonlinear model produces lower peripheral tissue temperatures and more effectively protects healthy tissue than the linear model, suggesting its superior appropriateness for therapeutic heating applications.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 4","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-026-07640-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738001","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}