Astrophysics and Space Science最新文献

{"title":"Nonlinear evolution of ion-acoustic wave packets in a weakly magnetized multi-ion plasma of the Venusian ionosheath","authors":"Adil Murad,&nbsp;Muhammad Adnan,&nbsp;Nabi Gul,&nbsp; Ikramullah,&nbsp;Fida Younus Khattak","doi":"10.1007/s10509-026-04642-9","DOIUrl":"10.1007/s10509-026-04642-9","url":null,"abstract":"<div><p>The nonlinear evolution of ion-acoustic wave packets is studied in a local, weakly magnetized Venusian multi-ion plasma model representative of the subsolar ionosheath and adjacent boundary regions. The model consists of superthermal electrons, solar-wind protons, and Venus-origin <span>(H^{+})</span> and <span>(O^{+})</span> ions; the electrons follow a <span>(kappa )</span> distribution and the ions are treated as warm fluids. In the low-frequency electrostatic limit, the direct Lorentz-force contribution of the weak induced magnetic field is neglected. A multiple-scale reductive perturbation analysis yields a nonlinear Schrödinger equation for a small-amplitude, quasi-monochromatic carrier. The three reported ion-acoustic branches are obtained simultaneously as the positive-frequency roots of the full coupled dispersion relation, rather than from three independent single-ion models. For the representative normalized parameter set, the phase and group characteristics depend on the ion thermal parameters and electron superthermality, and the oxygen-dominated branch has the largest calculated modulational-instability growth rate. Bright and dark envelope solutions occur in the focusing and defocusing regimes, respectively. These results identify conditions under which localized electrostatic envelopes may form in a compositionally mixed Venusian plasma. They are theoretical predictions within a homogeneous, collisionless, weak-amplitude fluid model and are not presented as direct detections of envelope solitons at Venus.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149034681","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}

{"title":"A rare non-drifting state in the subpulse drifting pulsar J1059-5742","authors":"L. H. Shang,&nbsp;H. X. Ma","doi":"10.1007/s10509-026-04640-x","DOIUrl":"10.1007/s10509-026-04640-x","url":null,"abstract":"<div><p>We report single-pulse observation of PSR J1059-5742 carried out with the 64-m Parkes radio telescope. Single-pulse analysis of the observation identifies three distinct emission states: a dominant subpulse-drifting state, a rare brighter non-drifting state, and short nulls. Our study show that 96.2% of the pulsar’s radio radiation is in the drifting state. In the drifting state, subpulses drift toward earlier longitudes, with drift periods of <span>(P_{3} = 5.7pm 0.5 P)</span> and <span>(P_{2} = 5.6pm 0.7^{circ })</span>. In the observation, we detect two rare non-drifting state events. The two non-drifting-state events persist for 107 and 108 rotation periods respectively. These two events accounted for 3.8% of the total observing time. Compared with single pulses in the drifting state, those in the non-drifting state are brighter, and the peak of the average pulse profile for the non-drifting state leads that of the drifting state by about <span>(2^{circ })</span> in spin longitude. This implies that changes may have occurred in the polar-cap discharge process or the magnetospheric configuration. Examination of the energies of all detected single-pulses revealed that the pulsar may have a nulling fraction of <span>(13pm 1%)</span>, and pulse nulling occurs only within the drifting state. The occasional cessation of drifting in PSR J1059-5742 may thus reveal a mode change of the polar-cap discharge.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986799","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}

{"title":"A multi-phase chronology of the Carrington storm of 1859 based on archival records of Trivandrum observatory","authors":"R. Jayakrishnan,&nbsp;Fazil C K,&nbsp;Ajesh A","doi":"10.1007/s10509-026-04634-9","DOIUrl":"10.1007/s10509-026-04634-9","url":null,"abstract":"<div><p>The rediscovery of bifilar magnetometer records from Trivandrum Observatory—preserved within the historical archives of the National Library of Scotland—provides a rare and independent equatorial dataset crucial for reassessing the intensity and temporal structure of the 1859 Carrington storm. These archival materials reveal a nuanced sequence of geomagnetic disturbances, in as response to a sequence of likely coronal mass ejection (CME) impacts on 16th August and 29th August preceding the well-known super storm of 2nd September, and subsequent magnetospheric disturbances on 5th, 13th and 15th September due to weaker CME events and/or solar wind streams. The analyses of the archived Aide’s bifilar magnetometer data show that the 29th August and 2nd September events were of comparable magnitude (<span>(Delta )</span>H ≈ −1851 nT and <span>(Delta )</span>H ≈ −1926 nT) respectively, positioning the former as a newly calibrated benchmark for pre-Carrington CME activity. The records evidence disrupted diurnal periodicity in the horizontal magnetic field intensity on 16th August, 5th September, 13th September and 15th September, underscoring the magnetospheric fluctuations which may have been induced by successive interplanetary CME (ICME) impacts. By leveraging these meticulously preserved observatory logs, this study reconstructs a multi-phase chronology of the Carrington storm.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986815","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}

{"title":"A perturbative approach to investigate nonlinear coherent structures in complex bipolar Saturnian plasmas","authors":"Tanushree Bezbaruah,&nbsp;Pralay Kumar Karmakar","doi":"10.1007/s10509-026-04637-6","DOIUrl":"10.1007/s10509-026-04637-6","url":null,"abstract":"<div><p>The propagation of nonlinear dust-acoustic structures in a dusty plasma environment of Saturn’s middle magnetosphere, specifically between the orbits of <i>Dione</i> and <i>Rhea</i>, is herein theoretically investigated. The model comprises oppositely charged (bipolar) dust grains treated as fluids, Maxwellian cold electrons and ions, and suprathermal hot electrons. Using the reductive perturbation method, a Korteweg-de Vries (KdV) equation is derived to describe weakly nonlinear dust-acoustic waves (DAWs), and its stationary solutions are analyzed numerically. The system supports rarefactive solitary waves, whose characteristics are strongly governed by the interplay between nonlinearity and dispersion. In particular, the equilibrium negative dust charge is found to play a decisive role in controlling the nonlinear behaviour and, consequently, the amplitude and profile of the solitary structures. The predicted electrostatic potential reaches amplitudes of the order of a few millivolts, while the associated electric field exhibits a bipolar signature in the mV/m range with a period of around a few hundreds of seconds. These results indicate the possible existence of ultra-low frequency nonlinear structures in the dusty regions of planetary magnetospheres and provide a theoretical basis for further investigations of low-frequency plasma dynamics in such environments.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986811","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}

{"title":"Application of machine learning to discover dynamical structures in 4D Poincaré maps in the circular restricted three-body problem","authors":"Kevin M. Trigg,&nbsp;Daniel J. Broyles,&nbsp;Robert A. Bettinger,&nbsp;Tyler J. Kapolka","doi":"10.1007/s10509-026-04638-5","DOIUrl":"10.1007/s10509-026-04638-5","url":null,"abstract":"<div><p>The spatial Circular Restricted Three-Body Problem (CR3BP) produces complex orbital dynamics that are difficult to classify at scale using traditional, manual Poincaré map analysis. A Poincaré map simplifies continuous orbital motion by recording the points where a trajectory intersects a chosen surface in phase space, converting a continuous path into a discrete set of crossings that reveal underlying topological structure. These crossings make it easier to characterize trajectory behavior, but interpreting them visually becomes impractical for large datasets and as Poincaré maps evolve from two into four dimensions. To address this challenge, an unsupervised clustering pipeline for discovering dynamical structures in four-dimensional (4D) Poincaré maps is introduced. Each trajectory’s Poincaré crossings are transformed into a compact feature representation capturing geometric dispersion, statistical, and frequency-based characteristics, enabling density-based clustering without prior labels. The method is evaluated across multiple Jacobi constants to assess robustness, and expanded to investigate chaining dynamical structures to find similar structures across different Jacobi constants. The results demonstrate that feature-based clustering can recover meaningful dynamical structures in high-dimensional trajectory data.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10509-026-04638-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986842","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}

{"title":"Astroclimatic conditions of the Suffa Plateau: optical and radiophysical parameters","authors":"Safarali B. Tursunkulov,&nbsp;Dilshod A. Raupov","doi":"10.1007/s10509-026-04617-w","DOIUrl":"10.1007/s10509-026-04617-w","url":null,"abstract":"<div><p>This paper presents the results of long-term astroclimatic and atmospheric monitoring conducted at the Suffa Plateau. Located at <span>(39^{circ }37^{prime }text{ N})</span> and <span>(67^{circ }56^{prime })</span> E, at an altitude of approximately 2300 m above sea level in the Turkestan Range, the Suffa Plateau is considered one of the most promising high-altitude astronomical sites in Central Asia for optical, millimeter-wave, and radio astronomical observations. The favorable astroclimatic conditions of the site are associated with its dry continental climate, relatively low precipitable water vapor (PWV), weak atmospheric turbulence, and low levels of radio-frequency interference. Optical seeing measurements obtained using a Differential Image Motion Monitor (DIMM) yielded median and mean nighttime seeing values of <span>(1.06^{prime prime })</span> and <span>(1.11^{prime prime })</span>, respectively, indicating relatively stable optical observing conditions. Long-term radiometric observations of atmospheric absorption and transparency were carried out using the dual-channel MIAP-2 millimeter-wave radiometer operating in the 84–99 GHz (3 mm) and 132–148 GHz (2 mm) atmospheric windows. Median and mean atmospheric absorption were 0.13 and 0.14 Np in the 2 mm channel and 0.11 and 0.12 Np in the 3 mm channel. Quantitative PWV retrievals were derived exclusively from the 2 mm channel, yielding median and mean PWV values of 4.96 and 5.91 mm, respectively, while the 3 mm channel was used primarily to characterize dry atmospheric opacity and long-term atmospheric transparency. Seasonal analysis demonstrates that winter months, particularly January and February, provide the most favorable conditions for millimeter-wave observations, when atmospheric absorption decreases by approximately <span>(50%)</span> relative to annual mean values. Additional comparison with ERA5 atmospheric reanalysis data confirms the general reliability and seasonal consistency of the radiometric PWV retrievals. The results indicate that the Suffa Plateau possesses favorable atmospheric conditions for a significant fraction of the year and represents a promising site for future optical, radio, and millimeter-wave astronomical facilities, including the RT-70 radio telescope currently under development.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986409","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}

{"title":"UV dose rates in Parsamian cometary nebulae: cosmic-ray-induced energetic processing of C2H2, H2CO, and CH3OH","authors":"A. Yeghikyan,&nbsp;M. Rah,&nbsp;L. Darbinyan,&nbsp;M. Alizadeh,&nbsp;S. Shamyar,&nbsp;S. Khachatryan","doi":"10.1007/s10509-026-04636-7","DOIUrl":"10.1007/s10509-026-04636-7","url":null,"abstract":"<div><p>We quantify absorbed UV dose rates for acetylene (C₂H₂), formaldehyde (H₂CO), and methanol (CH₃OH) in Parsamian cometary nebulae (Pa 13 and Pa 21) under two physical scenarios: a static molecular cloud (<span>(n(mathrm{H}_{2}) = 10^{3}text{ cm}^{-3})</span>) and a gravitationally collapsing core (<span>(n(r) propto r^{-1.5})</span>, from <span>(10^{18})</span> to <span>(10^{14}text{ cm})</span>). The energy source is the internal UV field from cosmic-ray (CR) excitation of H₂ via the Prasad–Tarafdar mechanism (parametrized following Padovani et al. 2024, validated with <span>cloudy</span> C25), with secondary electrons (<span>({sim }30text{--}50text{ eV})</span>) dominating at <span>(r leq 10^{14}text{ cm})</span> (<span>(n geq 10^{9}text{ cm}^{-3})</span>). Integrated over <span>(10^{6})</span> years, doses reach <span>({sim }10^{3}text{ eV},text{molecule}^{-1})</span> (static) and exceed <span>(10^{4}text{ eV},text{molecule}^{-1})</span> (collapsing), several orders of magnitude above the single-electron reaction threshold for glycine formation and within the energetically permissive regime identified in laboratory ice-irradiation studies, enabling isoprene (C₅H₈) precursor formation via acetylene polymerization. The C₂H₂/CH₃OH abundance ratio is the key diagnostic separating the prebiotic (isoprene) from the carbonaceous (PAH) pathway, placing Pa 13 and Pa 21 within the regime for complex prebiotic chemistry.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986442","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}

{"title":"Temporal delay characteristics of photometric maxima in the (i)-band of type Ia supernovae","authors":"Xiaoyin Chen,&nbsp;Rongjun Zhang,&nbsp;Xiangyun Zeng,&nbsp;Sheng Zheng,&nbsp;Zhengxue Chang,&nbsp;Yao Huang","doi":"10.1007/s10509-026-04633-w","DOIUrl":"10.1007/s10509-026-04633-w","url":null,"abstract":"<div><p>To investigate the physical origin of the secondary maximum in the <span>(i)</span>-band of Type Ia Supernovae (SNe Ia) and assess its application value in supernova physics research, a sample of 33 nearby SNe Ia with well-sampled <span>(i)</span>-band light curves from the LSQ/LCO collaboration and recent low-redshift follow-up data were selected. A comprehensive method combining SNooPy2 light curve fitting, Continuous Wavelet Transform (CWT) for objective peak identification, and Bayesian multi-Gaussian decomposition for peak parameter quantification was adopted to systematically analyze the temporal characteristics of the secondary maximum and its correlation with key physical parameters of SNe Ia. The results show that the temporal parameters of the secondary maximum have a significant negative correlation with the light curve decline rate <span>(Delta m_{15})</span>, among which the time interval between the primary and secondary maxima (<span>(mu _{3})</span>-<span>(mu _{1})</span>) has the strongest correlation (<span>(R^{2} approx 0.98)</span>, slope <span>({approx} -13.61 pm 0.37text{ days/magnitude})</span>). The epoch of the secondary maximum is found to track both the <span>(B-V)</span> and <span>(g-i)</span> colour-peak epochs (Pearson <span>(rapprox 0.77)</span> and <span>(rapprox 0.92)</span>, respectively), supporting the interpretation that these colour turnovers and <span>(mu _{3})</span> trace related phases of the post-maximum thermal evolution. These quantitative relationships provide a new perspective for investigating the thermal evolution and explosion physics of SNe Ia, and may offer a potential avenue for refining their use as standardizable candles in future cosmological studies.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986290","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}

{"title":"Phantom scalar charge as a control parameter for optical geometry and photon orbit stability around black holes","authors":"Indrajit Halder","doi":"10.1007/s10509-026-04635-8","DOIUrl":"10.1007/s10509-026-04635-8","url":null,"abstract":"<div><p>A phantom scalar field substantially alters the strong-field behavior of black hole spacetimes. We systematically investigate how the phantom scalar charge <span>(alpha )</span> influences null geodesics through the geometry of the optical manifold and the photon dynamics. By examining the Gaussian and geodesic curvatures of the optical geometry, we demonstrate that the phantom parameter <span>(alpha )</span> governs a smooth crossover from a strongly curved, intense-gravity regime to a stable weak-field regime. The present work also employs phase-portrait analysis using logarithmic and semi-logarithmic plots. We show that the Gaussian curvature encodes a smooth crossover between strong and weak-curvature regimes in the optical manifold. Furthermore, we explore how key observables—such as the effective potential, photon trajectories, the photon-sphere radius, the black hole shadow, and both weak and strong deflection angles—depend on <span>(alpha )</span>. We additionally evaluate the Lyapunov exponent <span>(lambda )</span>, which quantifies the instability of circular null geodesics in the photon sphere. This exponent attains its maximum at the radius of the photon sphere (<span>(r_{text{ph}})</span>) and decreases as <span>(r_{text{ph}})</span> increases. The phantom charge <span>(alpha )</span> systematically reduces the Lyapunov exponent <span>(lambda )</span>, smoothing the effective potential and lowering orbital instability. For small <span>(alpha )</span>, one recovers a Schwarzschild-like strong instability with a steep potential, while for large <span>(alpha )</span>, gravitational focusing is weakened, the optical geometry is reshaped, and null orbits become more stable. Our results indicate that the phantom scalar charge acts as a control parameter governing both the geometry and the stability of black hole photon regions.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986230","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}

{"title":"Probing fundamental cosmology with the dark ages 21-cm signal","authors":"Deepthi Moorkanat,&nbsp;Anoop Krishna,&nbsp;Hiten Hiten,&nbsp;R. V. Sadhaiv,&nbsp;Shinde Tejaswini Dadaso,&nbsp;Rajesh Mondal","doi":"10.1007/s10509-026-04632-x","DOIUrl":"10.1007/s10509-026-04632-x","url":null,"abstract":"<div><p>The cosmic dark ages offer a pristine, astrophysically unadulterated window into fundamental cosmology. Unlike the two-dimensional snapshot provided by the cosmic microwave background (CMB), the redshifted 21-cm signal from neutral hydrogen enables a three-dimensional tomographic view of cosmic evolution, observable through both the sky-averaged (global) signal and through analyzing spatial fluctuations across scales (power spectrum). In this work, we present comparative observational forecasts for three representative non-standard scenarios: Excess Radio Background (ERB) model (<span>(A_{r} = 0.001)</span>), co-SIMP dark matter model (<span>(C_{mathrm{int}} = 1.5)</span>) and the Starobinsky (ST) model of inflation featuring a localized primordial power suppression at <span>(k_{text{dip}} approx 7.5text{ Mpc}^{-1})</span>. Assuming a single-antenna spectrometer on the lunar far side integrating for 1000 hours, we find that the standard <span>(Lambda )</span>CDM global signal can be detected relative to null at <span>(4.12sigma )</span>. The co-SIMP global signal is detectable relative to null at <span>(4.67sigma )</span> and can be distinguished from standard <span>(Lambda )</span>CDM at <span>(2.76sigma )</span> significance, whereas the ERB model is detectable relative to null at <span>(3.86sigma )</span> but can only be distinguished from standard cosmology at <span>(0.29sigma )</span>. For spatial power spectrum observations over 10,000 hours using a compact <span>(25text{ km}^{2})</span> lunar far-side interferometer array, we forecast detection significances relative to null of <span>(1.97sigma )</span> (<span>(Lambda )</span>CDM), <span>(2.26sigma )</span> (ERB), <span>(4.50sigma )</span> (co-SIMP), and <span>(1.61sigma )</span> (ST). The spatial power spectrum enables model-discrimination significances relative to standard cosmology of <span>(3.32sigma )</span> for the co-SIMP model, <span>(0.29sigma )</span> for the ERB model, and <span>(0.13sigma )</span> for the ST model.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"371 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927173","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}