Astrophysics and Space Science最新文献

Shock evolution in the solar atmosphere with non-ideal effects 具有非理想效应的太阳大气中的激波演化

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-05-08 DOI: 10.1007/s10509-026-04582-4

Ekta Jain, Dhanpal Singh, S. D. Ram

引用次数: 0

Stable equilibria and fractal basin under Yukawa gravitational correction in the generalised photogravitational RTBP with a disc 广义光引力圆盘RTBP在汤川引力修正下的稳定平衡与分形盆地

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-05-07 DOI: 10.1007/s10509-026-04578-0

Nikshita Pandya, Ram Kishor

{"title":"Stable equilibria and fractal basin under Yukawa gravitational correction in the generalised photogravitational RTBP with a disc","authors":"Nikshita Pandya, Ram Kishor","doi":"10.1007/s10509-026-04578-0","DOIUrl":"10.1007/s10509-026-04578-0","url":null,"abstract":"<div><p>The Yukawa potential exhibits an exponential decay to the classical Newtonian inverse-square law, parametrised by the dimensionless coupling strength <span>(alpha )</span> and screening length <span>(lambda )</span>, providing a versatile framework for examining finite-range gravitational modifications. This study investigates the effects of Yukawa corrections on the existence and linear stability analysis of equilibrium points along with associated fractal basins of attraction in the generalized photogravitational restricted three-body problem (RTBP), incorporating a gravitational potential from a surrounding disc or belt-like structure. The analysis conducts a parallel examination of three representative celestial systems, Proxima-Centauri, Sun-Mars and Sun-Saturn systems as illustrative cases across different mass regimes. Numerical explorations indicate that the non-collinear equilibrium points exhibit a singular value for <span>(alpha = alpha _{0} approx -0.0309282 )</span>. Moreover, the critical mass parameter <span>(mu _{c})</span> is found to decrease, monotonically with increasing values of <span>(alpha in (-1,1))</span> and <span>(lambda in (0, infty ))</span>, wherein progressively negative values of <span>(alpha )</span> lead to expansion of the stability domain. Additionally, the basins of attraction, which are computed through multivariate Newton-Raphson method, exhibit fractal structures that reflect the convergence properties of the iterative scheme. This investigation demonstrates that Yukawa-type modifications, significantly alter the equilibrium configurations, their stability domains and convergence properties, offering deeper understanding of gravitational interactions beyond the classical Newtonian framework.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147829603","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

Enabling critical science through a new mission: the chromospheric magnetism explorer 通过一项新的任务实现关键科学：色球磁场探测器

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-05-06 DOI: 10.1007/s10509-026-04574-4

Holly Gilbert, Rebecca Centeno, Alfred de Wijn, Paul Bryans

{"title":"Enabling critical science through a new mission: the chromospheric magnetism explorer","authors":"Holly Gilbert, Rebecca Centeno, Alfred de Wijn, Paul Bryans","doi":"10.1007/s10509-026-04574-4","DOIUrl":"10.1007/s10509-026-04574-4","url":null,"abstract":"<div><p>The Chromospheric Magnetism Explorer (<i>CMEx</i>) is a NASA Heliophysics Small Explorers (SMEX) mission concept in an extended Phase A. <i>CMEx</i> uses ultraviolet spectropolarimetry to diagnose magnetism from the solar photosphere to the transition region, exploring how the magnetic field evolves from the dynamically-driven photosphere to the magnetically-dominated corona to form twisted non-potential flux ropes in the corona. This key transition happens in the chromosphere where only UV spectropolarimetry can give access to the highly complex dynamics where plasma properties change rapidly. Recent advances in the understanding of the polarization of UV chromospheric lines, which are not observable from the ground, have primed a space-based mission like <i>CMEx</i> for success. <i>CMEx</i> observes many near-UV spectral lines, including the well-known Mg II h and k lines as well as a series of Fe II lines, with full-Stokes polarimetry to provide quantitative diagnostics of plasma parameters densely sampling the 9 pressure scale heights in the chromosphere. This enables studies of how the magnetic field in and around active regions gets reconfigured leading up to the eruption process, how flares lead to persistent changes in photospheric and chromospheric magnetic fields, and what the large-scale magnetic structure of prominences is in their stable phase, and how it changes in the transition from equilibrium to eruption. Here we summarize the planned science and its implementation enabled by the mission concept.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10509-026-04574-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147829560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

The dynamical environment of Kepler–223 planetary system 开普勒- 223行星系统的动力学环境

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-05-04 DOI: 10.1007/s10509-026-04575-3

Carlos E. Chavez, Adrián Fierro, Ándres Avilés

{"title":"The dynamical environment of Kepler–223 planetary system","authors":"Carlos E. Chavez, Adrián Fierro, Ándres Avilés","doi":"10.1007/s10509-026-04575-3","DOIUrl":"10.1007/s10509-026-04575-3","url":null,"abstract":"<div><p>The Kepler space telescope was a successful mission that used the transit method. Multi–planetary systems are interesting because they are dynamically rich due to the planets’ interactions. Kepler’s mission was the first to find a system with four planets all in resonance, that is <i>Kepler–223</i>. The <i>Kepler–223</i> system is of unique dynamical interest as the first exoplanetary system confirmed to host four sub–Neptune planets in a precise 3:4:6:8 resonant chain. Previous dynamical studies have struggled to fully recover the long–term phase protection mechanisms, often finding that higher–order resonant angles circulate rather than librate. In this work, we re–examine the dynamical state of <i>Kepler–223</i> by performing high–resolution N–body integrations and constructing detailed stability maps in the <span>((a,e))</span> phase space, we demonstrate that the system is locked in a deeper resonant state than previously thought. Crucially, we find that all resonant arguments, exhibit robust libration over secular timescales. Our stability maps reveal that the planets reside in clearly defined stability islands that allow for higher eccentricities than previous estimates. We further compare these numerical islands with analytical resonance widths and find excellent agreement for the inner three planets, while the outermost planet (<i>Kepler–223</i>e) exhibits a stability region wider than first–order analytical theories predict, suggesting complex multi–body stabilization effects at the edge of the chain.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 5","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147807588","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

Formation of classical Be-stars of the early spectral subclass in the case of nonconservative mass transfer in close binary systems 紧密双星系统中非保守传质情况下早期光谱亚类经典be星的形成

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-04-28 DOI: 10.1007/s10509-026-04577-1

Evgeny Staritsin

{"title":"Formation of classical Be-stars of the early spectral subclass in the case of nonconservative mass transfer in close binary systems","authors":"Evgeny Staritsin","doi":"10.1007/s10509-026-04577-1","DOIUrl":"10.1007/s10509-026-04577-1","url":null,"abstract":"<div><p>Spin-up of a mass gaining component in a binary system is considered taking into account the mass loss from the system during the mass transfer between components in the Hertzsprung gap. The angular momentum that the accreting component gains during mass transfer depends on the increase in the mass of the component at this stage. The increase in the mass was considered over a broad range, from 5% to 100%. The case is considered when, after mass transfer, the mass of the accreting component has a value of 16 <span>(M_{odot })</span>, typical for early Be stars. The transfer of angular momentum within the accreting component occurs due to meridional circulation and shear turbulence. If the accreted mass accounts for more than 30%, the accretor obtains a rotation typical of early Be-stars. This conclusion does not depend on: a) the rotation of the accreting component before mass transfer, b) the amount of angular momentum coming from the boundary layer located between the star and the accretion disk, c) a possible decrease in the angular velocity of the disk below the Keplerian value, d) the efficiency of turbulence in the interior of the accretor.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147796805","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

Prediction of the annual maximum sunspot number for Solar Cycles 22, 23, 24 and 25 via the geomagnetic activity indices aa and Ap 利用地磁活动指数aa和Ap预测太阳周期22、23、24和25的年最大黑子数

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-04-24 DOI: 10.1007/s10509-026-04573-5

Mukul Mohan, Ravindra Pratap Patel

引用次数: 0

Observational constraints on varying-((G,Lambda )) cosmology with DESI DR2 DESI DR2对变化- ((G,Lambda ))宇宙学的观测约束

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-04-24 DOI: 10.1007/s10509-026-04576-2

S. Mandal, A. Singh, R. Chaubey

{"title":"Observational constraints on varying-((G,Lambda )) cosmology with DESI DR2","authors":"S. Mandal, A. Singh, R. Chaubey","doi":"10.1007/s10509-026-04576-2","DOIUrl":"10.1007/s10509-026-04576-2","url":null,"abstract":"<div><p>We examine an isotropic cosmological framework in which both the gravitational constant <span>(G)</span> and the cosmological term <span>(Lambda )</span> evolve with cosmic time. The varying dark energy explains the different features of the universe in the considered framework. For the power-law parametrization for <span>(G)</span>, we solve the corresponding cosmological equations to obtain the expansion rate. In order to determine the robust observational constraints on model parameters, we employ the latest DESI DR2 BAO measurements with the Cosmic Chronometers (CC) and Pantheon+SH0ES (PPS) data. The likelihood is constructed using the Markov chain Monte Carlo (MCMC) analysis and compared for the estimated parameters. The evolution of cosmological parameters such as the Hubble parameter, deceleration parameter, effective equation of state parameter are analyzed to investigate the cosmic evolution and dynamical behavior of the model. The late-time accelerating scenario of model has also been tested for bounds on <span>(dot{G}/G)</span> and information criterion to describe its performance with <span>(Lambda )</span>CDM model.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147738725","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

Low-latitude ionospheric TEC variability during Solar Cycle 24: assessment of IRI models using ANN 太阳活动周期24期间低纬度电离层TEC变率：利用人工神经网络评估IRI模式

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-04-17 DOI: 10.1007/s10509-026-04571-7

Nitin Dubey, Swati, Sparsh Agarwal, Dhananjali Singh, Devbrat Pundhir

{"title":"Low-latitude ionospheric TEC variability during Solar Cycle 24: assessment of IRI models using ANN","authors":"Nitin Dubey,  Swati, Sparsh Agarwal, Dhananjali Singh, Devbrat Pundhir","doi":"10.1007/s10509-026-04571-7","DOIUrl":"10.1007/s10509-026-04571-7","url":null,"abstract":"<div><p>Understanding long-term ionospheric total electron content (TEC) variability is crucial for enhancing satellite-based communication and navigation systems, particularly in low-latitude regions where ionospheric dynamics are highly complex. In this study, GNSS-derived TEC data from five low-latitude stations were analyzed during Solar Cycle 24 (2010-2020) and compared with the IRI-2016 and IRI-2020 models. Statistical analyses were performed across diurnal, seasonal, and solar-activity phases, and TEC variations were further predicted using an artificial neural network (ANN)-based NARX model. Strong correlations were observed between TEC and solar activity indices (0.83-0.99), while moderate correlations were obtained with geomagnetic indices (Dst and <span>(Sigma )</span>Kp). The IRI models reproduced the general TEC morphology but exhibited systematic overestimations and underestimations at specific stations, particularly near the equatorial ionization anomaly crest. In contrast, the ANN model demonstrated superior performance, yielding consistently low RMSE values across training, validation, and testing datasets. Entropy analysis revealed slightly enhanced variability during equinox periods, indicating increased ionospheric complexity. These results highlight the limitations of empirical models at low latitudes and demonstrate the effectiveness of data-driven approaches for accurate TEC prediction. This study uniquely integrates long-term multi-station TEC analysis, empirical model evaluation (IRI-2016 and IRI-2020), ANN-based prediction, and entropy-based complexity assessment within a unified framework, providing a comprehensive understanding of ionospheric variability over Solar Cycle 24.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737888","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

Strange quark matter cosmology in LRS Bianchi type-III universe LRS Bianchi iii型宇宙中的奇异夸克物质宇宙学

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-04-16 DOI: 10.1007/s10509-026-04572-6

A Patra, S Panda, R. N Patra

{"title":"Strange quark matter cosmology in LRS Bianchi type-III universe","authors":"A Patra, S Panda, R. N Patra","doi":"10.1007/s10509-026-04572-6","DOIUrl":"10.1007/s10509-026-04572-6","url":null,"abstract":"<div><p>We investigate the cosmological implications of strange quark matter in a four-dimensional locally rotationally symmetric (LRS) Bianchi type-III universe within the framework of General Relativity. By adopting the MIT bag equation of state, exact analytical solutions of the Einstein field equations are obtained for different expansion phases of the universe, in which the bag constant naturally emerges as an effective vacuum energy component. The resulting cosmological evolution exhibits a transition from an early radiation-dominated. The Hubble parameter is explicitly expressed as a function of redshift and confronted with cosmic chronometer and baryon acoustic oscillation data using a Markov Chain Monte Carlo analysis. The combined CC+BAO constraints </p><div><div><span>$$ H_{0} = 69.91^{+2.43}_{-1.94}~mbox{km},mbox{s}^{-1},mbox{Mpc}^{-1}, quad Omega _{Lambda }= 0.59^{+0.11}_{-0.18}, quad Omega _{k} = 0.37^{+0.09}_{-0.12}, $$</span></div></div><p> provides a qualitatively consistent description of anisotropic strange quark matter models while remaining consistent with late-time expansion measurements within a negatively curved cosmological framework. Although the imposed LRS symmetry leads to vanishing shear and effective isotropization, the intrinsic spatial curvature remains dynamically relevant at early times and leaves observable imprints on the expansion history of the universe. These results indicate that strange quark matter, through its bag constant contribution, can provide an effective and consistent description unifying early radiation-dominated evolution with late-time cosmic acceleration.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737378","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

New way to date globular clusters: Brown dwarf cooling sequences 确定球状星团日期的新方法：棕矮星冷却序列

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2026-04-13 DOI: 10.1007/s10509-026-04563-7

Roman Gerasimov

{"title":"New way to date globular clusters: Brown dwarf cooling sequences","authors":"Roman Gerasimov","doi":"10.1007/s10509-026-04563-7","DOIUrl":"10.1007/s10509-026-04563-7","url":null,"abstract":"<div><p>As the oldest building blocks of our Galaxy, globular clusters retain the archaeological footprint of the early stellar environments. Accurate absolute ages of globular clusters are required to interpret this ancient record. Existing dating techniques often produce precise but discordant ages, suggestive of systematic errors in excess of 1 Gyr. The James Webb Space Telescope (JWST) has unlocked a new dating method that leverages the cooling behavior of previously unobservable brown dwarf members. With a largely independent set of systematic errors, this new method provides a new consistency test for more established methodologies. I present a likelihood-based histogram-free method to derive globular cluster ages from multi-band JWST photometry of cluster members near and below the hydrogen-burning limit. By applying the method to a large set of simulated observations, I establish that formal age errors (i.e. errors based on measurement uncertainties alone) under 0.2 Gyr are attainable for nearby globular clusters. I also evaluate the significance of associated systematic effects, including the chemical heterogeneity of globular clusters (multiple populations), unresolved binary systems and uncertainties in brown dwarf cooling rates. As with other methods of age determination, systematic effects dominate the error budget (in selected cases, by over an order of magnitude), but may be reduced with more sophisticated analysis. Finally, I provide a lookup table for determining the number of observations, exposure times and temporal baselines required to estimate the age of a given cluster to a prescribed precision.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 4","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10509-026-04563-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147737664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0