Chinese Journal of Physics最新文献

{"title":"QUENCH: Quantum unraveling in enhanced nonlinear CTP hydrodynamics","authors":"Matthew James Stephenson","doi":"10.1016/j.cjph.2024.02.048","DOIUrl":"10.1016/j.cjph.2024.02.048","url":null,"abstract":"<div><div>We introduce the linear subgroup of volume-preserving diffeomorphism as the underlying symmetry to construct an action within the effective field theory framework and the Schwinger–Keldish formalism. The formulated action is posited to effectively incorporate dissipative effects into the Navier–Stokes equations.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"93 ","pages":"Pages 437-441"},"PeriodicalIF":4.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140089487","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}

{"title":"Flow and heat transfer analysis of an ionanofluid above a rotating disk undergoing torsion","authors":"Dibjyoti Mondal,&nbsp;Amit Kumar Pandey,&nbsp;Abhijit Das","doi":"10.1016/j.cjph.2024.11.024","DOIUrl":"10.1016/j.cjph.2024.11.024","url":null,"abstract":"<div><div>The convective heat transfer properties of traditional nanofluids and ionic liquid-based nanofluids (ionanofluids) are crucial in engineering applications such as heat exchangers, electronics cooling, and energy storage. Given the relevance of the rotating disk flow model in these applications, this study examines the boundary layer flow and heat transfer resulting from the torsional motion of a rough rotating disk, specifically considering <span><math><mrow><msub><mrow><mi>Al</mi></mrow><mrow><mn>2</mn></mrow></msub><msub><mrow><mi>O</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow></math></span> and <span><math><mi>Cu</mi></math></span> nanoparticles dispersed in water and the ionic liquid <span><math><mrow><mrow><mo>[</mo><msub><mrow><mi>C</mi></mrow><mrow><mn>4</mn></mrow></msub><mi>m</mi><mi>i</mi><mi>m</mi><mo>]</mo></mrow><mrow><mo>[</mo><mi>N</mi><msub><mrow><mrow><mo>(</mo><mi>T</mi><mi>f</mi><mo>)</mo></mrow></mrow><mrow><mn>2</mn></mrow></msub><mo>]</mo></mrow></mrow></math></span> under a vertical magnetic field. The boundary value problem governing this flow is first shown to have a solution through a topological shooting method. Numerical integrations via a collocation method (SQLM) are then used to evaluate the flow and heat transfer characteristics. The results show that torque requirements decrease with the torsional exponent <span><math><mi>m</mi></math></span>, with water requiring more torque than <span><math><mrow><mrow><mo>[</mo><msub><mrow><mi>C</mi></mrow><mrow><mn>4</mn></mrow></msub><mi>m</mi><mi>i</mi><mi>m</mi><mo>]</mo></mrow><mrow><mo>[</mo><mi>N</mi><msub><mrow><mrow><mo>(</mo><mi>T</mi><mi>f</mi><mo>)</mo></mrow></mrow><mrow><mn>2</mn></mrow></msub><mo>]</mo></mrow></mrow></math></span> to sustain rotation. Notably, <span><math><mrow><mrow><mo>[</mo><msub><mrow><mi>C</mi></mrow><mrow><mn>4</mn></mrow></msub><mi>m</mi><mi>i</mi><mi>m</mi><mo>]</mo></mrow><mrow><mo>[</mo><mi>N</mi><msub><mrow><mrow><mo>(</mo><mi>T</mi><mi>f</mi><mo>)</mo></mrow></mrow><mrow><mn>2</mn></mrow></msub><mo>]</mo></mrow></mrow></math></span>-based fluids exhibit a higher heat transfer enhancement than water. Lamina-shaped nanoparticles deliver the highest heat transfer rates compared to other shapes (spherical, cylindrical, and columnar). Furthermore, the entropy generation number <span><math><mrow><mi>N</mi><mi>S</mi></mrow></math></span> declines with increased azimuthal slip parameter <span><math><msub><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span>, thermal slip parameter <span><math><msub><mrow><mi>λ</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span>, and torsional exponent <span><math><mi>m</mi></math></span>. This indicates that entropy generation can be controlled by incorporating torsional motion with thermal slip on an anisotropic rough disk, while also carefully selecting other governing parameters.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"93 ","pages":"Pages 127-157"},"PeriodicalIF":4.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167084","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}

{"title":"Singularity-free dark energy star in Rastall gravity","authors":"Debadri Bhattacharjee,&nbsp;Pradip Kumar Chattopadhyay","doi":"10.1016/j.cjph.2024.11.035","DOIUrl":"10.1016/j.cjph.2024.11.035","url":null,"abstract":"<div><div>The notion of dark energy presents a potential avenue to avoid the gravitational collapse of compact objects, leading to singularities. The present article is devoted primarily to study a novel singularity-free relativistic solution of the Einstein field equations for dark energy stars in the framework of the Rastall theory of gravity. To analyse our model, we consider the Low-Mass X-ray Binary (LMXB) 4U 1608-52 having a mass of <span><math><mrow><mn>1</mn><mo>.</mo><mn>74</mn><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span> and a radius of 9.3 km (Güver et al., 2010) as a possible dark energy star candidate. We begin with the dark energy equation of state, where the density of dark energy is proportional to the isotropic perfect fluid distribution through a coupling parameter <span><math><mi>α</mi></math></span>. We compute the induced metric and extrinsic curvature tensors at the stellar hyper-surface to evaluate the necessary unknown constants appearing in the model. We conduct a thorough and comprehensive analysis to demonstrate the dependence of the physical behaviour of the model on the Rastall parameter <span><math><mrow><mo>(</mo><mi>ξ</mi><mo>)</mo></mrow></math></span>, and interestingly, we obtain a possible phase transition from the dark to baryonic profile, which is sensitive to both <span><math><mi>α</mi></math></span> and <span><math><mi>ξ</mi></math></span>. We also compute the percentage of dark energy present in the model by varying <span><math><mi>ξ</mi></math></span>. However, for a fixed value of <span><math><mi>ξ</mi></math></span>, the percentage variation of dark energy with the mass of a star shows that the percentage of dark energy depends on the mass and radius of a star. The causality and energy conditions are well met in the present model, which describes its physical acceptability. The stability of the stellar configuration is established through the study of stability analysis. The graphical nature of the physical parameters and the present theoretical study show that our proposed model is non-singular and a viable representation of a stable realistic stellar structure in the presence of dark and baryonic matter simultaneously.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"93 ","pages":"Pages 183-201"},"PeriodicalIF":4.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143168053","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}

{"title":"Lepton masses and mixings with broken μ−τ symmetry in a B – L extended 3HDM based on (Z2×Z4)⋊Z2  (I) symmetry","authors":"V.V. Vien","doi":"10.1016/j.cjph.2024.12.010","DOIUrl":"10.1016/j.cjph.2024.12.010","url":null,"abstract":"<div><div>We propose a <span><math><mrow><mi>B</mi><mo>−</mo><mi>L</mi></mrow></math></span> extended three-Higgs-doublet model (3HDM) based on non-Abelian symmetry <span><math><mrow><mrow><mo>(</mo><msub><mrow><mi>Z</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>×</mo><msub><mrow><mi>Z</mi></mrow><mrow><mn>4</mn></mrow></msub><mo>)</mo></mrow><mo>⋊</mo><msub><mrow><mi>Z</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> <!--> <!-->(I) in the light of the Type-I seesaw mechanism for explaining the smallness of neutrino mass, the lepton mass hierarchy and the lepton mass and mixing. The resulting Dirac and Majorana neutrino mass matrices hint for a realistic lepton mixing pattern in which the <span><math><mrow><mi>μ</mi><mo>−</mo><mi>τ</mi></mrow></math></span> symmetry is broken by the contribution from the charged-lepton sector. The hierarchy of lepton masses is naturally achieved and the constraints on the effective neutrino mass is consistent with the recent experimental constraints.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"93 ","pages":"Pages 418-429"},"PeriodicalIF":4.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143168054","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}

{"title":"Nonlinear steady Darcy-Bénard convection problem: Revisit using the heatlines approach","authors":"K.M. Lakshmi ,&nbsp;P.G. Siddheshwar ,&nbsp;D. Laroze ,&nbsp;P. Díaz","doi":"10.1016/j.cjph.2025.01.032","DOIUrl":"10.1016/j.cjph.2025.01.032","url":null,"abstract":"<div><div>The classical problem of Darcy-Bénard convection(<span><math><mrow><mi>D</mi><mi>B</mi><mi>C</mi></mrow></math></span>) in enclosures is revisited using the method of heatlines to have a better perspective of the problem. General aspect ratio is chosen in the analysis which helps in obtaining the results of four different types of enclosures, viz., tall, square, shallow and very shallow. Three different water saturated porous media<span><math><mrow><mo>(</mo><mi>W</mi><mi>S</mi><mi>P</mi><mi>M</mi><mo>)</mo></mrow></math></span> and their actual thermophysical properties are used in the computation of the results. The method of heatlines facilitates the observation of fluid and heat flow lines in order to have a good understanding of the dynamics. The neo-classical approach not only accurately predicts the critical Darcy-Rayleigh and wave numbers but also picturizes the heat flow of the problem in the most natural way. The Galerkin method is used in the paper for the normal and convective modes of convection yields accurate analytical results in the heatlines formulation. Theoretical expression to calculate the number of Bénard cells that form in the system at onset is obtained by linear theory, and ranges of aspect ratio at which unicellular, two-cellular and multicellular convection are possible are determined and documented. The weakly non-linear stability analysis is performed to determine the heat transport. Among four considered enclosures, maximum heat transport is achieved in the case of a square enclosure. Out of three chosen <span><math><mrow><mi>W</mi><mi>S</mi><mi>P</mi><mi>M</mi></mrow></math></span>, the water-saturated glass balls porous medium and the water-saturated aluminium-foam porous medium show most stable and least stable behaviours. Results obtained from the heatlines approach are validated by comparing with the results of the classical <span><math><mrow><mi>D</mi><mi>B</mi><mi>C</mi></mrow></math></span> problem in the case of a very shallow enclosure. From the study, we conclude that the square enclosure with water-saturated aluminium-foam porous medium has possible application in heat removal systems.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"94 ","pages":"Pages 328-346"},"PeriodicalIF":4.6,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387155","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}

{"title":"Unsteady and quasi-steady shear stress under oscillating flow of a viscoelastic fluid in a cylindrical pipe","authors":"Jahon Akilov ,&nbsp;Mamasoli Dzhabbarov ,&nbsp;Bakhtiyor Khuzhayorov ,&nbsp;Fadzilah Md Ali","doi":"10.1016/j.cjph.2025.01.030","DOIUrl":"10.1016/j.cjph.2025.01.030","url":null,"abstract":"<div><div>This paper examines the oscillatory laminar flow of a viscoelastic fluid in a pipe with circular cross-section. The linear Oldroyd equation is adopted as the rheological equation. Expressions for the transfer and frequency functions in the Laplace transforms are derived. The ratio of unsteady and quasi-steady wall shear stress, in contrast to the quasi-steady approach, depends on the parameter expressing the acceleration of fluid flow. Computational experiments were carried out to determine the unsteady wall shear stress. It is established that with increasing acceleration of the fluid flow, the unsteady shear stress increases for a viscous fluid, while for a viscoelastic fluid it also depends on the relaxation parameters. For certain frequencies, the transient shear stress depends almost linearly on frequency. For a Maxwell fluid, the dependence of unsteady shear stress on frequency has an oscillatory character. The differences between these results and the results obtained based on the quasi-steady approach are shown. Influence of viscoelastic properties of the fluid on dynamics of unsteady shear stress is also studied. The results obtained show that the viscoelastic properties of the fluid act as a limiting factor when using a quasi-steady approach to determine the unsteady wall shear stress. It was shown that the acceleration of fluid flow acts in the same manner.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"94 ","pages":"Pages 365-379"},"PeriodicalIF":4.6,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394413","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}

{"title":"Magnetic structure of ternary intermetallic Tb3Co4Sn13 with nonchiral crystal structure","authors":"Chin-Wei Wang ,&nbsp;Chia-Nung Kuo ,&nbsp;Chin-Shan Lue ,&nbsp;R.O. Piltz ,&nbsp;Chi-Hung Lee","doi":"10.1016/j.cjph.2025.01.017","DOIUrl":"10.1016/j.cjph.2025.01.017","url":null,"abstract":"<div><div>Single crystals of the ternary stannide Tb₃Co₄Sn₁₃ were synthesized using the tin self-flux method. This article reports the results of magnetic susceptibility, specific heat, and neutron diffraction studies. The title compound undergoes a structural phase transition at <em>T_D</em> of 89.4 K and a magnetic ordering temperature <em>T_N</em> of 11.3 K. The crystal structure transitions from a high-temperature <em>Pm</em>-3<em>n</em> structure to a rhombohedral <em>R</em>-3<em>c</em> structure, and this transition is accompanied by an increase in unit cell volume at <em>T_D</em>. Tb³⁺ is the only magnetic species in the compound, with spins entering long-range magnetic order states below <em>T_N</em>.​ The magnetic space group is <em>R</em>-3′<em>c</em> (#167.105), the maximal subgroup of the proposed <em>R</em>-3<em>c</em> structure. Also investigated was the isostructural Nd₃Co₄Sn₁₃. The same <em>R</em>-3<em>c</em> model fits the low-temperature structure of Nd₃Co₄Sn₁₃, and the magnetic space group is identified as <em>R</em>-3′<em>c</em>' (#167.106), consistent with the structure reported in the authors’ previous study.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"94 ","pages":"Pages 355-364"},"PeriodicalIF":4.6,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394414","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}

{"title":"The “echo” effect in response to a current pulse acting on a superconductor in a magnetic field","authors":"A.N. Maksimova,&nbsp;A.N. Moroz,&nbsp;S.V. Pokrovskii,&nbsp;D.A. Aleksandrov,&nbsp;V.A. Kashurnikov","doi":"10.1016/j.cjph.2025.01.037","DOIUrl":"10.1016/j.cjph.2025.01.037","url":null,"abstract":"<div><div>The response of a layered high-temperature superconductor to a current pulse of microsecond duration has been calculated in the framework of a two-dimensional model of a layered HTS. In the external magnetic field, an “echo” effect is observed, i.e., a voltage increase in the sample after the current is completely switched off. This effect is observed at low temperatures and disappears near 70 K. The effect persists when the duration of the current pulse is increased. The effect persists as the duration of the trailing edge of the pulse increases. The occurance of this effect is associated with the flow of the vortex lattice after the transport current is switched off.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"94 ","pages":"Pages 250-261"},"PeriodicalIF":4.6,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372136","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}

{"title":"A new black hole coupled with nonlinear electrodynamics surrounded by quintessence: Thermodynamics, geodesics, and Regge–Wheeler potential","authors":"Ahmad Al-Badawi ,&nbsp;Faizuddin Ahmed","doi":"10.1016/j.cjph.2025.01.021","DOIUrl":"10.1016/j.cjph.2025.01.021","url":null,"abstract":"<div><div>We present a new exact solution to the gravitational field equations, where nonlinear electrodynamics (NLED) serves as the matter source in the presence of a quintessence field (QF). This solution describes a static, spherically symmetric black hole in the context of Anti-de Sitter (AdS) space, with the black hole (BH) surrounded by quintessence matter. The resulting black hole solution generalizes the AdS Schwarzschild–Kiselev black hole and reduces to the standard AdS-Schwarzschild black hole in the appropriate limits. Additionally, under certain conditions, this solution recovers the Bardeen–Kiselev regular black hole. We further explore the horizon structure and thermodynamic properties of this new black hole spacetime, accounting for the contributions from both NLED and the QF, including the state parameter of the QF. These contributions modify the spacetime geometry, thereby altering the thermodynamic behavior of the black hole. Moreover, we analyze the geodesic equations and show how NLED and the QF influence the effective potential for massless photon particles. Finally, we study the Regge–Wheeler (RW) potential for this regular black hole and demonstrate how variations in the parameters (NLED and QF) affect the RW potential for fields of different spins: spin-zero (<span><math><mrow><mi>S</mi><mo>=</mo><mn>0</mn></mrow></math></span>), spin-one (<span><math><mrow><mi>S</mi><mo>=</mo><mn>1</mn></mrow></math></span>), and spin-two (<span><math><mrow><mi>S</mi><mo>=</mo><mn>2</mn></mrow></math></span>). To illustrate the effects, we provide graphical representations of the RW potential for both multipole numbers <span><math><mrow><mi>ℓ</mi><mo>=</mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mi>ℓ</mi><mo>=</mo><mn>1</mn></mrow></math></span>.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"94 ","pages":"Pages 185-203"},"PeriodicalIF":4.6,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348464","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}

{"title":"Constraints on Λ(t)CDM cosmology using cosmic chronometers and supernova data","authors":"Yerlan Myrzakulov ,&nbsp;M. Koussour ,&nbsp;M. Bulanbay ,&nbsp;S. Muminov ,&nbsp;J. Rayimbaev","doi":"10.1016/j.cjph.2025.01.025","DOIUrl":"10.1016/j.cjph.2025.01.025","url":null,"abstract":"<div><div>In this manuscript, we investigate the constraints on dynamical vacuum models within the framework of <span><math><mrow><mi>Λ</mi><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow></mrow></math></span>CDM cosmology by assuming a parameterization of the vacuum energy density as <span><math><mrow><msub><mrow><mi>ρ</mi></mrow><mrow><mi>Λ</mi></mrow></msub><mrow><mo>(</mo><mi>t</mi><mo>)</mo></mrow><mo>=</mo><msub><mrow><mi>ρ</mi></mrow><mrow><mi>Λ</mi><mn>0</mn></mrow></msub><mfenced><mrow><mn>1</mn><mo>+</mo><mi>α</mi><mrow><mo>(</mo><mn>1</mn><mo>−</mo><mi>a</mi><mo>)</mo></mrow></mrow></mfenced></mrow></math></span>, where <span><math><msub><mrow><mi>ρ</mi></mrow><mrow><mi>Λ</mi><mn>0</mn></mrow></msub></math></span> is the present vacuum density and <span><math><mi>α</mi></math></span> is a free parameter. We use 31 cosmic chronometer data points and 1048 Pantheon type Ia supernova samples to constrain the model parameters. Our statistical analysis employs Markov Chain Monte Carlo (MCMC) simulations. We have found that the universe is currently undergoing accelerated expansion, transitioning from a decelerating phase. The transition redshift <span><math><mrow><msub><mrow><mi>z</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>6</mn><msubsup><mrow><mn>5</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>19</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>03</mn></mrow></msubsup></mrow></math></span> obtained from the combined CC+SNe dataset is consistent with recent constraints. The total EoS indicates an accelerating phase, with density parameters for matter and vacuum energy exhibiting expected behaviors. The <span><math><mrow><mi>O</mi><mi>m</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow></mrow></math></span> diagnostic shows distinct behaviors for different datasets, and the present value of the jerk parameter deviates slightly from the <span><math><mi>Λ</mi></math></span>CDM model but remains consistent within uncertainties. These findings support the dynamic nature of dark energy and provide valuable constraints on the evolution of the universe.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"94 ","pages":"Pages 287-297"},"PeriodicalIF":4.6,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378976","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}