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Stagnation point of the triple nanoparticle nanofluid flow through the spinning sphere with radiation absorption 带有辐射吸收的三重纳米粒子纳米流体流经旋转球的停滞点
IF 2.219 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02768-5
Kotha Gangadhar, Naga Chandrika G, Saeed Dinarvand
{"title":"Stagnation point of the triple nanoparticle nanofluid flow through the spinning sphere with radiation absorption","authors":"Kotha Gangadhar, Naga Chandrika G, Saeed Dinarvand","doi":"10.1007/s12043-024-02768-5","DOIUrl":"https://doi.org/10.1007/s12043-024-02768-5","url":null,"abstract":"<p>Heat absorption and thermal radiation have significant roles in engineering and research. These two principles have applications in thermal transportation, gas turbines, nuclear power plants, electrical fuel, aerospace engineering, projectiles and renewable energy. The present work analyses the stagnation point ternary nanofluid motion over a circulating sphere in the presence of a magnetic field and radiation absorption. The nonlinear controlling equations are replaced by ordinary differential equations by applying a suitable comparison factor. The bvp4c process was used to establish numerical outcomes of the partial differential equations. This mathematical numerical findings are presented graphically. The results of ternary nanoparticles (Cu–Ag–CuO/water), hybrid nanoparticles (Cu–Ag/water) and copper (Cu) nanoparticles have also been compared, and this comparison suggests that ternary nanoparticles (Cu–Ag–CuO/water) are more effective at attenuating hemodynamic factors (such as wall shear stress and heat transfer) than hybrid and copper (Cu) nanoparticles. Comparison with previous literature results is also done and the results are found to be in very good agreement with those published earlier.</p>","PeriodicalId":743,"journal":{"name":"Pramana","volume":null,"pages":null},"PeriodicalIF":2.219,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141588508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
引用次数: 0
Microscopic parametrization of the near threshold oscillations of the nucleon time-like effective electromagnetic form factors 核子时样有效电磁形式因子近阈值振荡的微观参数化
IF 3.043 3区 物理与天体物理
The European Physical Journal A Pub Date : 2024-07-11 DOI: 10.1140/epja/s10050-024-01365-9
Francesco Rosini, Simone Pacetti, Olga Shekhovtsova, Egle Tomasi-Gustafsson
{"title":"Microscopic parametrization of the near threshold oscillations of the nucleon time-like effective electromagnetic form factors","authors":"Francesco Rosini, Simone Pacetti, Olga Shekhovtsova, Egle Tomasi-Gustafsson","doi":"10.1140/epja/s10050-024-01365-9","DOIUrl":"https://doi.org/10.1140/epja/s10050-024-01365-9","url":null,"abstract":"<p>We present an analysis of the recent near threshold BESIII data for the nucleon time-like effective form factors. The damped oscillation emerging from the subtraction of the dipole formula is treated in non-perturbative-QCD, making use of the light cone distribution amplitudes expansion. Non-perturbative effects are accounted for by considering <span>(Q^2)</span>-dependent coefficients in such expansions, whose free parameters are determined by fitting to the proton and neutron data. Possible implications and future analysis have been discussed.</p>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":null,"pages":null},"PeriodicalIF":3.043,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141585678","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}
引用次数: 0
Design of elastic metamaterial plate and application in subway vibration isolation 弹性超材料板的设计及在地铁隔振中的应用
IF 2.584 4区 材料科学
Applied Physics A Pub Date : 2024-07-11 DOI: 10.1007/s00339-024-07691-5
Qian Wang, Linchang Miao, Haizhong Zheng, Peng Xiao, Benben Zhang
{"title":"Design of elastic metamaterial plate and application in subway vibration isolation","authors":"Qian Wang, Linchang Miao, Haizhong Zheng, Peng Xiao, Benben Zhang","doi":"10.1007/s00339-024-07691-5","DOIUrl":"https://doi.org/10.1007/s00339-024-07691-5","url":null,"abstract":"<p>While using the subway brings people convenient transportation, The low frequency vibration caused by metro is one of the factors that seriously threaten the physical and mental health of human beings and the working environment. Phononic crystals structure and elastic metamaterials have been favored for the past few years because of their excellent low frequency vibration control properties. In this paper, based on local resonance theory, an elastic metamaterial thick plate structure is designed to attenuate low frequency vibration. Through plane wave expansion method and numerical simulation, the dispersion curve and reduced vibration effect of the thick plate structure are simulated and analyzed, and it is proved that the elastic metamateric thick plate structure opens the bend wave band gap range of 36–110 Hz within the limits of lower frequency below 150 Hz. Finally, a kind of new lower frequency vibration isolation thick plate barrier is designed to minish the effect of low-frequency vibration, which has a potential engineering application foreground in the field of low-frequency vibration control and isolation of subway.</p>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":null,"pages":null},"PeriodicalIF":2.584,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141588589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
X-ray emission spectrum for axion–photon conversion in magnetospheres of strongly magnetized neutron stars 强磁化中子星磁层中轴子-光子转换的 X 射线发射光谱
IF 4.59 2区 物理与天体物理
The European Physical Journal C Pub Date : 2024-07-11 DOI: 10.1140/epjc/s10052-024-13051-7
Shubham Yadav, M. Mishra, Tapomoy Guha Sarkar
{"title":"X-ray emission spectrum for axion–photon conversion in magnetospheres of strongly magnetized neutron stars","authors":"Shubham Yadav, M. Mishra, Tapomoy Guha Sarkar","doi":"10.1140/epjc/s10052-024-13051-7","DOIUrl":"https://doi.org/10.1140/epjc/s10052-024-13051-7","url":null,"abstract":"<p>Detecting axionic dark matter (DM) could be possible in an X-ray spectrum from strongly magnetized neutron stars (NSs). We examine the possibility of axion–photon conversion in the magnetospheres of strongly magnetized NSs. In the current work, we investigate how the modified Tolman–Oppenheimer–Volkoff (TOV) system of equations (in the presence of a magnetic field) affects the energy spectrum of axions and axions-converted-photon flux. We have considered the distance-dependent magnetic field in the modified TOV system of equations. We employ three different equations of states (EoSs), namely APR, FPS, and SLY, to solve these equations. We obtain the axions emission rate by including the Cooper-pair-breaking formation process and Bremsstrahlung process in the core of NSs using the NSCool code. We primarily focus on Magnificient seven (M7) star RXJ 1856.5-3754. We further investigate the impact of the magnetic field on the actual observables, such as axion energy spectrum and axion-converted-photon flux at an axion mass in meV range by assuming mass <span>(M_{NS} sim 1.4M_{odot }.)</span> We compare our calculated axion-converted-photon flux from all available archival data sets from PN+MOS+Chandra. We also study the variation of the energy spectrum at a fixed energy with varying central magnetic fields. Our predicted axion-converted-photon flux values as a function of axion energy closely follow the experimentally archival data, which allows us to put bounds on the axion mass for the three EoS.</p>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":null,"pages":null},"PeriodicalIF":4.59,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141587556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
引用次数: 0
Resonance behaviour for a bistable system driven by random-phase square-wave signal-modulated noise and multiplicative noise 由随机相位方波信号调制噪声和乘法噪声驱动的双稳态系统的共振行为
IF 2.219 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02807-1
Feng Guo, Cheng-Yin Zhu, Qiang-Ming Cai, Jian-Wei Wang
{"title":"Resonance behaviour for a bistable system driven by random-phase square-wave signal-modulated noise and multiplicative noise","authors":"Feng Guo, Cheng-Yin Zhu, Qiang-Ming Cai, Jian-Wei Wang","doi":"10.1007/s12043-024-02807-1","DOIUrl":"https://doi.org/10.1007/s12043-024-02807-1","url":null,"abstract":"<p>The stochastic resonance (SR) phenomenon for a bistable system subject to signal-modulated noise and to multiplicative and additive noise is investigated. The signal is modelled as a random-phase asymmetric square-wave one. Based on adiabatic approximation condition and two-state theory, the system output signal-to-noise ratio (SNR) is deduced. It is found that double SR phenomenon occurs when the SNR varies with the asymmetry of the square-wave signal. One resonance peak appears when the SNR changes with the amplitude of the square-wave signal. Traditional SR can be observed on the curves of the SNRs vs. the strength of the signal-modulated noise and vs. the intensities of the multiplicative and additive noise. The non-monotonous dependence of the SNR on the system parameter is discussed.</p>","PeriodicalId":743,"journal":{"name":"Pramana","volume":null,"pages":null},"PeriodicalIF":2.219,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141588630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
引用次数: 0
Enhancing heat transfer on the free convection of conducting hybrid nanofluid through stretching/shrinking surface 通过拉伸/收缩表面增强导电混合纳米流体的自由对流传热
IF 2.219 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02762-x
Ram Prakash Sharma, P K Pattnaik, S R Mishra, Seema Tinker, Subba Rao Allipudi
{"title":"Enhancing heat transfer on the free convection of conducting hybrid nanofluid through stretching/shrinking surface","authors":"Ram Prakash Sharma, P K Pattnaik, S R Mishra, Seema Tinker, Subba Rao Allipudi","doi":"10.1007/s12043-024-02762-x","DOIUrl":"https://doi.org/10.1007/s12043-024-02762-x","url":null,"abstract":"<p>A study is carried out for the flow of a steady two-dimensional hybrid nanofluid through an exponentially expanding/shrinking surface under the influence of a magnetic field. Further, the impact of thermal buoyancy is also incorporated into the momentum equation. The model is developed using the rheological properties of hybrid nanofluid, such as viscosity, conductivity, specific heat, etc. that develop the physical significance of nanofluid. The principal equations for the motion are re-constructed to their dimensionless form by implementing similarity transformation and these are handled numerically using Runge–Kutta fourth-order. The crux of the problem is that the dual solution is obtained for the particular flow parameters. Further, the simulation is carried out by setting the characterising parameters, and their characteristics are explained briefly. The important outcomes of the study are: for the enhanced volume concentration the velocity profile enhances significantly in the case of the first solution and the impact is opposite in the case of the second solution.</p>","PeriodicalId":743,"journal":{"name":"Pramana","volume":null,"pages":null},"PeriodicalIF":2.219,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141586880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
引用次数: 0
Exclusive charmonium production at the electron-ion collider in China 中国电子-离子对撞机的独家粲生产
IF 4.59 2区 物理与天体物理
The European Physical Journal C Pub Date : 2024-07-11 DOI: 10.1140/epjc/s10052-024-13033-9
Xue Wang, Xu Cao, Aiqiang Guo, Li Gong, Xiao-Shen Kang, Yu-Tie Liang, Jia-Jun Wu, Ya-Ping Xie
{"title":"Exclusive charmonium production at the electron-ion collider in China","authors":"Xue Wang, Xu Cao, Aiqiang Guo, Li Gong, Xiao-Shen Kang, Yu-Tie Liang, Jia-Jun Wu, Ya-Ping Xie","doi":"10.1140/epjc/s10052-024-13033-9","DOIUrl":"https://doi.org/10.1140/epjc/s10052-024-13033-9","url":null,"abstract":"<p>We investigate the exclusive <span>(J/psi )</span> production at the future Electron-ion collider in China by utilizing the eSTARlight event generator. We model the cross-section and kinematics by fitting to the world data of <span>(J/psi )</span> photoproduction. Projected statistical uncertainties on <span>(J/psi )</span> production are based on the design of a central detector, which consists of a tracker and vertex subsystem. The precision of the pseudo-data allows us to probe the near-threshold mechanism, e.g. the re-scattering effect. The significance of the forward amplitudes is discussed as well. The design and optimization of the detector enhance the potential for exploring the near-threshold region and the realm of high four-momentum transfer squared, which is of particular interest on several physics topics.</p>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":null,"pages":null},"PeriodicalIF":4.59,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141587553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
引用次数: 0
Molecular dynamics insights into nanoscale lubrication: a comparative study of regimes 分子动力学对纳米级润滑的启示:制度比较研究
IF 2.584 4区 材料科学
Applied Physics A Pub Date : 2024-07-11 DOI: 10.1007/s00339-024-07712-3
Mohsen Motezaker, Shaoping Xiao, Amir R. Khoei, Jabbar Ali Zakeri
{"title":"Molecular dynamics insights into nanoscale lubrication: a comparative study of regimes","authors":"Mohsen Motezaker, Shaoping Xiao, Amir R. Khoei, Jabbar Ali Zakeri","doi":"10.1007/s00339-024-07712-3","DOIUrl":"https://doi.org/10.1007/s00339-024-07712-3","url":null,"abstract":"<p>This study utilizes molecular dynamics simulations to explore the tribological behavior of rough surfaces across various lubrication regimes—boundary, mixed, and elastohydrodynamic (EHL)—at the nanoscale. The analysis not only highlights the distinct interactions between asperity contacts and lubricant films but also introduces novel insights into how lubricant film thickness and surface roughness interplay to dictate frictional dynamics. The analysis reveals that in dry contact, surface roughness quickly stabilizes despite an initial increase in contact area, indicating a dominant role of asperity interlocking that influences frictional resistance. Transitioning to boundary lubrication, the presence of a lubricant layer modifies the contact mechanics, leading to a slower root mean square (RMS) reduction of surface roughness and a more gradual increase in friction force, emphasizing the lubricant’s protective effect against asperity flattening. Nevertheless, under lower loads, this protective effect can lead to increased frictional forces compared to dry contact due to higher final roughness. Mixed lubrication maintains a near-constant contact area after initial contact, with any variations in friction force primarily occurring in the early cycles due to rapid asperity flattening. In the EHL regime, the formation of a complete lubricant film between surfaces results in the lowest friction forces, dominated by viscous shear rather than direct asperity contact. Unique to this study is the quantification of these effects under realistic roughness conditions (RMS of 1.2 nm). These regime-specific behaviors underline the nuanced interplay between RMS, contact area, and friction forces, and enhance our understanding of the fundamental principles guiding the design of lubrication strategies for advanced mechanical systems.</p>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":null,"pages":null},"PeriodicalIF":2.584,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141587087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Numerical investigation of tunable and switchable refractive index-based mid-infrared metamaterial absorber 基于折射率的可调谐和可切换中红外超材料吸收器的数值研究
IF 2.219 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02789-0
Nikita Choudhary, Anjani Kumar Tiwari
{"title":"Numerical investigation of tunable and switchable refractive index-based mid-infrared metamaterial absorber","authors":"Nikita Choudhary, Anjani Kumar Tiwari","doi":"10.1007/s12043-024-02789-0","DOIUrl":"https://doi.org/10.1007/s12043-024-02789-0","url":null,"abstract":"<p>In this paper, we numerically investigate a tunable and switchable metamaterial absorber operating in the mid-infrared region. The metamaterial structure comprises an array of metal–dielectric concentric nanodisks and a metal square patch on a substrate coated with thin dielectric and metal layers. The two dielectric regions induce two absorption bands, which can be independently tuned by changing the refractive index and geometrical parameters of the dielectric layers. In an optimised geometry, a dual-band to a single-band switchable frequency response is achieved by interchanging the refractive index of the dielectric layers. The origin of the resonant absorptions is traced to the simultaneous excitation of electric and magnetic fields in the dielectric regions. Due to architectural symmetry, the investigated structure is polarisation-insensitive and exhibits high absorption over a wide range of angles.</p>","PeriodicalId":743,"journal":{"name":"Pramana","volume":null,"pages":null},"PeriodicalIF":2.219,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141586882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
引用次数: 0
Study of neutrinoless double beta decay in the Standard Model extended with sterile neutrinos 标准模型中的无中微子双β衰变研究
IF 4.59 2区 物理与天体物理
The European Physical Journal C Pub Date : 2024-07-11 DOI: 10.1140/epjc/s10052-024-13024-w
Debashree Priyadarsini Das, Sasmita Mishra
{"title":"Study of neutrinoless double beta decay in the Standard Model extended with sterile neutrinos","authors":"Debashree Priyadarsini Das, Sasmita Mishra","doi":"10.1140/epjc/s10052-024-13024-w","DOIUrl":"https://doi.org/10.1140/epjc/s10052-024-13024-w","url":null,"abstract":"<p>We study a model where the Standard Model is augmented with three sterile neutrinos. By adopting a particular parameterization of a <span>((6times 6))</span> unitary matrix—in this context, light neutrino masses being generated via a type-I seesaw mechanism—we analytically derive the masses of the sterile states using an exact seesaw relation. The masses of the sterile states are derived in terms of the lightest mass of active neutrinos and active–active and active–sterile mixing angles and phases; they can be all light, all heavy, or a mixture of light and heavy compared to the active states. This can be attributed to the interplay of the <i>CP</i>-violating (CPV) phases of the mixing matrix. As both active and sterile states can mediate the neutrinoless double beta decay (<span>(0nu beta beta )</span>) process, their contributions to the effective mass of the electron neutrino, <span>(|m_{ee}|)</span>, become a function of the mass of the lightest active state and active–active and active–sterile mixing angles and phases. We explore the parameter space of <span>(|m_{ee}|)</span>, keeping in mind the present and future sensitivity of <span>(0nu beta beta )</span> decay searches. By making use of constraints from charged lepton flavor-violating (cLFV) processes and non-unitarity, we explore the role of additional CPV phases and active–sterile mixing angle values. The numerical values thus obtained for <span>(|m_{ee}|)</span> can vary from as low as <span>(mathscr {O}(10^{-4}))</span> to saturating the present experimental limit. We also check the reliability of our result by calculating the branching ratio of <span>(mu rightarrow e gamma )</span>, a prominent cLFV process, and non-unitarity in this framework.</p>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":null,"pages":null},"PeriodicalIF":4.59,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141587552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
引用次数: 0
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