The European Physical Journal Plus最新文献

{"title":"Effect of temperature and electrode patches on the flow structure and heat transfer of dielectric liquid","authors":"Yuan Ma,&nbsp;Haosheng Yu,&nbsp;M. M. Rashidi,&nbsp;Rasul Mohebbi,&nbsp;Zhigang Yang","doi":"10.1140/epjp/s13360-025-06187-2","DOIUrl":"10.1140/epjp/s13360-025-06187-2","url":null,"abstract":"<div><p>Electro-thermo-convection (ETC) plays a critical role in heat transfer enhancement, particularly in dielectric fluids subjected to external electric fields. However, the impact of temperature and electrode patch arrangements on the flow structure and heat transfer characteristics of ETC remains underexplored. This study systematically investigates the influence of these factors within a square cavity using the lattice Boltzmann method (LBM). The effects of Rayleigh number (5000 ≤ Ra ≤ 50,000), electric Rayleigh number (100 ≤ <i>T</i> ≤ 200), and patch aspect ratio (0.05 ≤ <i>AR</i> ≤ 0.95) are analyzed. The results show that varying AR significantly alters the flow structure, charge density, and electric potential distribution. Notably, for Ra = 5000 and 10,000, increasing <i>T</i> enhances heat transfer, with the highest average Nusselt number (Nu_avg) observed at <i>AR</i> = 0.05 and <i>T</i> = 200, leading to a 36% and 30% increase, respectively. However, at Ra = 50,000, the effect of <i>T</i> on Nu_avg becomes less pronounced. These findings provide new insights into optimizing ETC for advanced thermal management applications.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688567","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":"Hawking radiation through tunneling from a hot NUT-Kerr–Newman-Kasuya-Anti-de Sitter black hole","authors":"Heisnam Shanjit Singh,&nbsp;Chiranjeeb Singha,&nbsp;Sraban Kumar Upadhyaya","doi":"10.1140/epjp/s13360-025-06186-3","DOIUrl":"10.1140/epjp/s13360-025-06186-3","url":null,"abstract":"<div><p>In this research work, we examine the tunneling phenomenon of a charged Dirac particle emerging from the thermal horizon of a hot NUT-Kerr–Newman-Kasuya-Anti-de Sitter (HNKNK-AdS) black hole. Using the tunneling formalism, we derive the Hawking temperature associated with the charged Dirac particle at the horizon of the HNKNK-AdS black hole. Our findings reveal that the effective Hawking temperature depends on various black hole parameters, including electric and magnetic charges, magnetic mass, the cosmological constant, and angular momentum. Additionally, the Hawking radiation for the Kerr–Newman black hole diminishes slightly, and a minor correction to the thermal radiation is identified. We also discuss the heat capacities of the HNKNK-AdS and find that there exists an infinite number of discontinuity implying that the black hole system becomes unstable as the smaller the event horizon of the black hole and hence deduces the well-known heat capacity for the Kerr–Newman black hole.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143668040","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":"Low-energy critical behavior in two-dimensional tilted semi-Dirac semimetals driven by fermion–fermion interactions","authors":"Wen Liu,&nbsp;Wen-Hao Bian,&nbsp;Xiao-Zhuo Chu,&nbsp;Jing Wang","doi":"10.1140/epjp/s13360-025-06154-x","DOIUrl":"10.1140/epjp/s13360-025-06154-x","url":null,"abstract":"<div><p>Employing the renormalization group approach, we carefully investigate the critical behavior of two-dimensional tilted semi-Dirac semimetals induced by the fermion–fermion interactions in the low-energy regime. After incorporating all one-loop corrections, we derive the coupled RG equations of all related parameters and introduce two distinct strategies, named as Strategy I and Strategy II, to describe different scenarios. A detailed numerical analysis yields several interesting behavior in the low-energy limit. At first, we notice that the fermion–fermion interactions either vanish or diverge in the Strategy I, depending on the initial values of the tilting parameter and the fermionic couplings, whereas these interactions in the Strategy II always diverge at a certain critical energy scale, which is associated with the initial conditions. Next, the microstructural parameter <span>(alpha )</span> and the fermion velocity <span>(v_F)</span> in the Strategy I share the similar behavior with their Strategy II counterparts. It is observed that fermion–fermion interactions lead to an increase in <span>(alpha )</span> while driving a decrease in <span>(v_F)</span>. Furthermore, the system can either be attracted by the Gaussian fixed point (GFP) or certain relatively fixed point (RFP) in the Strategy I. However, it always flows toward the RFP in the Strategy II at the lowest-energy limit. These results would provide helpful insights into the studies on observable quantities and phase transitions in the two-dimensional tilted semi-Dirac semimetals and the analogous semimetals.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143668277","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":"Quasiparticle solutions for the nonlocal NLSE with an anti-Hermitian term in semiclassical approximation","authors":"Anton Kulagin,&nbsp;Alexander Shapovalov","doi":"10.1140/epjp/s13360-025-06183-6","DOIUrl":"10.1140/epjp/s13360-025-06183-6","url":null,"abstract":"<div><p>We deal with the <i>n</i>-dimensional nonlinear Schrödinger equation (NLSE) with a cubic nonlocal nonlinearity and an anti-Hermitian term, which is widely used model for the study of open quantum system. We construct asymptotic solutions to the Cauchy problem for such equation within the formalism of semiclassical approximation based on the Maslov complex germ method. Our solutions are localized in the neighbourhood of a few points for every given time, i.e. form some spatial pattern. The localization points move over trajectories that are associated with the dynamics of semiclassical quasiparticles. The Cauchy problem for the original NLSE is reduced to the system of ordinary differential equations and auxiliary linear equations. The semiclassical nonlinear evolution operator is derived for the NLSE. The general formalism is applied to the specific one-dimensional and two-dimensional NLSEs with a periodic trap potential, dipole-dipole interaction, and phenomenological damping. It is shown that the long-range interactions in such model, which are considered through the interaction of quasiparticles in our approach, can lead to drastic changes in the behaviour of our asymptotic solutions.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143668275","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":"Rad-hard silicon carbide thermal neutron detectors for quality assurance in BNCT","authors":"Roberto Bedogni,&nbsp;Miguel Angel Caballero-Pacheco,&nbsp;Luigi Russo,&nbsp;Abner Ivan Castro-Campoy,&nbsp;Dolzodmaa Dashdondog,&nbsp;Felipe Lopes Frigi,&nbsp;Alessandro Calamida,&nbsp;Fabio Moro,&nbsp;Antonino Pietropaolo","doi":"10.1140/epjp/s13360-025-06149-8","DOIUrl":"10.1140/epjp/s13360-025-06149-8","url":null,"abstract":"<div><p>Quality Assurance in BNCT dosimetry includes the determination of spatial distributions of thermal neutrons in a water phantom. Activation foils are typically adopted as thermal neutron detectors, making measurements time consuming and requiring considerable manpower. This process would be greatly simplified if an active thermal neutron sensor existed which could scan the volume of a water phantom, as done in conventional radiotherapy with electron LINACs. To this aim, an experiment was organised using rad-hard Silicon Carbide Schottky diodes with active area 1 mm², sensitized to thermal neutrons with a 30 μm ⁶LiF coating. To operate in water, they were made waterproof through a customised 3D printed plastic holder. A suitable neutron field was produced by degrading the 14 MeV beam from the ENEA Frascati Neutron Generator with an assembly formed by a copper-lead shielding followed by a water phantom. The thermal neutron fluence achieved in the water phantom was in the order of 2–3 × 10⁵ cm⁻² s⁻¹. The spatial distribution of thermal neutrons in water was measured using both the Silicon Carbide Schottky diodes and the gold activation foils. The experiment was fully simulated with MCNP. This paper presents the results of the experiment and the possible implications for Quality Assurance in BNCT dosimetry.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06149-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143668276","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":"Exploring anomalous flavour-changing neutral tqh transitions at future muon colliders: insights from (mu ^{+}mu ^{-}rightarrow tbar{q}h) interactions","authors":"Eda Alici","doi":"10.1140/epjp/s13360-025-06210-6","DOIUrl":"10.1140/epjp/s13360-025-06210-6","url":null,"abstract":"<div><p>Flavour-changing neutral current (FCNC) interactions between the Higgs boson and the top quark are subject to significant suppression within the Standard Model. Consequently, these interactions can only attain an observable level through the influence of Beyond the Standard Model (BSM) physics effects. It is therefore of great importance to investigate these rare interactions, both to test the limits of the Standard Model and to reveal new physical signatures. At this point, the high sensitivity, clean experimental environment and low systematic uncertainties provided by muon colliders allow for a detailed study of such rare processes. In this context, the present study analyses the signal of the process <span>(mu ^+mu ^- rightarrow tbar{q}h)</span> and the background processes <span>(tbar{t})</span>, <span>(tWbar{b})</span>, <i>WWh</i> and <i>WW</i> at both in <span>(sqrt{s} = 1)</span> TeV and <span>(sqrt{s} = 3)</span> TeV energy levels. Analyses at the 1 TeV energy level reveal the observability of FCNC interactions even at low energy conditions and achieve the limit <span>(text {Br}(t rightarrow qH) = 1.96 times 10^{-4})</span>. This result corresponds to an improvement of approximately 1.5 times compared to the current limits of the ATLAS experiment, which are <span>(3.0 times 10^{-4})</span>. On the other hand, at the 3 TeV energy level, the most stringent limit was calculated under the luminosity <span>(mathcal {L} = 20 ab^{-1})</span>, yielding a value of <span>(text {Br}(t rightarrow qH) = 1.1 times 10^{-4})</span>. This result coincides an improvement of approximately 3 times with respect to the current ATLAS experimental limits. The findings of the study underscore the potential of muon colliders in the search for new physics and the pivotal role they can play in the study of rare processes such as Higgs-top quark interactions. Consequently, the results are expected to provide a crucial foundation for both experimental and theoretical studies and to make a significant contribution to the search for BSM physics.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06210-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143655329","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":"Diagnostic characterisation of masonry and decorative materials of the apsidal area of the Cathedral of Cefalù (Sicily, Italy)","authors":"Antonella Bertino,&nbsp;Silvia Portale,&nbsp;Alessia Coccato,&nbsp;Paolo Mazzoleni,&nbsp;Germana Barone","doi":"10.1140/epjp/s13360-025-06176-5","DOIUrl":"10.1140/epjp/s13360-025-06176-5","url":null,"abstract":"<div><p>The Cathedral of Cefalù (Sicily, Italy), a UNESCO World Heritage Site since 2015, was built during the Norman rule and is famous for its magnificent mosaic. The mosaic apparatus, located in the apsidal area of the Cathedral, recently underwent extensive conservation work. Besides the mosaic <i>tesserae</i>, this area of the Cathedral was subjected to interventions aimed at preserving the integrity of masonry plasters, mortars, stuccoes and coloured plasters. However, basic information such as the chemical and mineralogical composition and microstructural arrangement of original materials was still lacking. In this perspective, in situ and ex situ analyses were carried out for the first time on the masonry and decorative materials of Cefalù’s Cathedral apse. Chemical analyses were carried out on original mosaic <i>tesserae</i> by means of portable X-ray fluorescence, highlighting that their manufacture involved the recycling of glass, excluding the use of natural glass and identifying the chromophores responsible for the wide colour variety<i>;</i> X-ray diffractometry was performed on masonry plasters and mortars allowing to recognise the use of predominantly carbonatic binders and the presence of degradation products such as calcium oxalates and sodium chloride; finally, petrographic observations carried out on stuccoes enabled the identification of various types of aggregates (carbonatic, gypsum-based, and quartz-feldspathic) embedded in a carbonatic binder, while petrographic analysis of the coloured plasters allowed the identification of three pigmentation techniques. Overall, these analyses provided very useful information on the nature of building and decorative materials as well as their mineralogical composition and degradation products, laying the foundations for future conservation work that takes into account the characteristics of each material.</p><h3>Graphic abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06176-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143655330","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":"Large-time wave patterns in higher-order lumps of the Mel’nikov equation","authors":"Xiuyu Tao,&nbsp;Qin Fang,&nbsp;Bo Yang","doi":"10.1140/epjp/s13360-025-06181-8","DOIUrl":"10.1140/epjp/s13360-025-06181-8","url":null,"abstract":"<div><p>In this paper, we study large-time wave patterns in higher-order lumps of the Mel’nikov equation. We show that two types of lump patterns appear when time is large. For the first type of lump patterns, it contains fundamental lumps uniformly distributed in triangular shapes, and this triangular pattern reverses its shape along the <i>x</i>- and <i>y</i>- directions when time goes from large negative to large positive. For the second type of lump patterns, it contains fundamental lumps distributed in non-triangular shapes in the outer region, together with possible fundamental lumps arranged in triangular shapes in the inner region. When time goes from large negative to large positive, the non-triangular pattern in the outer region occurs a linear transformation which involves actions such as dilation, rotation, stretch, shear and transitions, while the triangular pattern, when it arises in the inner region, reverses its shapes along the <i>x</i>- and <i>y</i>- axis. In general, these wave patterns are related to root structures of the Yablonskii-Vorob’ev polynomials and the Wronskian–Hermit polynomials. Leading-order predictions of lump locations at large time also analytically derived, and excellent agreement is observed when compared to true solutions.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645606","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":"Landau levels for massive disclinated graphene-based topological insulator","authors":"G. Q. Garcia,&nbsp;J. R. S. Oliveira,&nbsp;P. J. Porfírio,&nbsp;C. Furtado","doi":"10.1140/epjp/s13360-025-06153-y","DOIUrl":"10.1140/epjp/s13360-025-06153-y","url":null,"abstract":"<div><p>In this work, we investigate the massive Kane–Mele model for graphene in the presence of disclination and an external magnetic field, where graphene behaves as a topological insulator. In the low-energy limit, the effective field equation for graphene is described by a Dirac equation with three different degrees of freedom. We succeed in decoupling the set of eight components of the Dirac equation by using the spin projector <span>({hat{C}})</span> in the disclinated geometry. As consequence, we obtain the Landau levels in this framework, in which we note the emergence of zero modes as edge states due to the inversion symmetry breaking. We also note that for different sites in sublattices <span>(mathcal {A/B})</span>, one can have different values of gap width.\u0000</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143655182","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":"Factorization way to symmetries of systems on curved spaces","authors":"Sergio Salamanca","doi":"10.1140/epjp/s13360-025-06174-7","DOIUrl":"10.1140/epjp/s13360-025-06174-7","url":null,"abstract":"<div><p>In a previous work we showcased the factorization method to find the symmetries of superintegrable systems with spherical separability in flat spaces. Here we analyze the same problem, but in constant curvature spaces along the examples of curved Kepler-Coulomb and harmonic oscillator systems. We also show how this procedure can also be directly extended to the curved Smorodinsky-Winternitz and Evans systems.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645441","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}