The Astrophysical Journal Letters最新文献_第2页

A High-Caliber View of the Bullet Cluster through JWST Strong and Weak Lensing Analyses 通过JWST强透镜和弱透镜分析子弹星团的高口径视图

The Astrophysical Journal Letters Pub Date : 2025-06-29 DOI: 10.3847/2041-8213/add2f0

Sangjun Cha, Boseong Young Cho, Hyungjin Joo, Wonki Lee, Kim HyeongHan, Zachary P. Scofield, Kyle Finner and M. James Jee

{"title":"A High-Caliber View of the Bullet Cluster through JWST Strong and Weak Lensing Analyses","authors":"Sangjun Cha, Boseong Young Cho, Hyungjin Joo, Wonki Lee, Kim HyeongHan, Zachary P. Scofield, Kyle Finner and M. James Jee","doi":"10.3847/2041-8213/add2f0","DOIUrl":"https://doi.org/10.3847/2041-8213/add2f0","url":null,"abstract":"The Bullet Cluster (1E 0657-56) is a key astrophysical laboratory for studying dark matter, galaxy cluster mergers, and shock propagation in extreme environments. Using new JWST imaging, we present the highest-resolution mass reconstruction to date, combining 146 strong lensing constraints from 37 systems with high-density (398 sources arcmin−2) weak lensing data, without assuming that light traces mass. The main cluster’s mass distribution is highly elongated (northwest–southeast) and consists of at least three subclumps aligned with the brightest cluster galaxies. The subcluster is more compact but elongated along the east–west direction, with a single dominant peak. We also detect a possible mass and intracluster light (ICL) trail extending from the subcluster’s eastern side toward the main cluster. Notably, these detailed features are closely traced by the ICL, with a modified Hausdorff distance of 19.80 ± 12.46 kpc. Together with multiwavelength data, the complex mass distribution suggests that the merger history of the Bullet Cluster may be more complex than previous binary cluster merger scenarios.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144516132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Decoding Long-duration Gravitational Waves from Binary Neutron Stars with Machine Learning: Parameter Estimation and Equations of State 用机器学习解码来自双中子星的长时间引力波：参数估计和状态方程

The Astrophysical Journal Letters Pub Date : 2025-06-29 DOI: 10.3847/2041-8213/ade42f

Qian Hu, Jessica Irwin, Qi Sun, Christopher Messenger, Lami Suleiman, Ik Siong Heng and John Veitch

{"title":"Decoding Long-duration Gravitational Waves from Binary Neutron Stars with Machine Learning: Parameter Estimation and Equations of State","authors":"Qian Hu, Jessica Irwin, Qi Sun, Christopher Messenger, Lami Suleiman, Ik Siong Heng and John Veitch","doi":"10.3847/2041-8213/ade42f","DOIUrl":"https://doi.org/10.3847/2041-8213/ade42f","url":null,"abstract":"Gravitational waves (GWs) from binary neutron stars (BNSs) offer a valuable understanding of the nature of compact objects and hadronic matter, and the science potential will be greatly enhanced by the third-generation (3G) GW detectors, which are expected to detect BNS signals with order-of-magnitude improvements in duration, detection rates, and signal strength. However, the resulting computational demands for analyzing such prolonged signals pose a critical challenge that existing Bayesian methods cannot feasibly address in the 3G era. To bridge this critical gap, we demonstrate a machine learning–based workflow capable of producing source parameter estimation and constraints on equations of state (EOSs) for hours-long BNS signals in seconds with minimal hardware costs. We employ efficient compression of the GW data and EOS using neural networks, based on which we build normalizing flows for inference that can deliver results in seconds. The optimized computational cost of BNS signal analysis with our framework shows that machine learning has the potential to be an indispensable tool for future catalog-level BNS analyses, paving the way for large-scale investigations of BNS-related physics across the 3G observational landscape.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"633 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144520611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Discovery of a Variable Yellow Supergiant Progenitor for the Type IIb SN 2024abfo 发现IIb型超新星SN 2024abfo的可变黄色超巨星祖星

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade4cd

Zexi Niu, 泽茜牛, Ning-Chen Sun, Justyn R. Maund, Zhen Guo, Wenxiong Li, Meng Sun, 萌孙 and Jifeng Liu

引用次数: 0

A Core-sensitive Mixed f/g-mode of the Sun Predicted by Wave Topology and Hydrodynamical Simulation 用波拓扑和流体力学模拟预测太阳的核敏感混合f/g模式

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade396

Arthur Le Saux, Armand Leclerc, Guillaume Laibe, Pierre Delplace and Antoine Venaille

引用次数: 0

An Ejection Event Captured by Very Long Baseline Interferometry during the Outburst of Swift J1727.8–1613 雨燕J1727.8-1613爆发期间的超长基线干涉测量捕获的弹射事件

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade0ab

Hongmin Cao, Jun Yang, Sándor Frey, Callan M. Wood, James C. A. Miller-Jones, Krisztina É. Gabányi, Giulia Migliori, Marcello Giroletti, Lang Cui, Tao An, Xiaoyu Hong and WeiHua Wang

{"title":"An Ejection Event Captured by Very Long Baseline Interferometry during the Outburst of Swift J1727.8–1613","authors":"Hongmin Cao, Jun Yang, Sándor Frey, Callan M. Wood, James C. A. Miller-Jones, Krisztina É. Gabányi, Giulia Migliori, Marcello Giroletti, Lang Cui, Tao An, Xiaoyu Hong and WeiHua Wang","doi":"10.3847/2041-8213/ade0ab","DOIUrl":"https://doi.org/10.3847/2041-8213/ade0ab","url":null,"abstract":"We observed a newly discovered Galactic black hole X-ray binary Swift J1727.8–1613 with the European VLBI Network (EVN) at 5 GHz. The observation was conducted immediately following a radio quenching event detected by the Karl G. Jansky Very Large Array. The visibility amplitude evolution over time reveals a large-amplitude radio flare and is consistent with an ejection event. The data can be interpreted either as a stationary component (i.e., the radio core) and a moving blob, or as two blobs moving away from the core symmetrically in opposite directions. The initial angular separation speed of the two components was estimated to 30 mas day−1. We respectively fitted a single circular Gaussian model component to each of 14 sliced visibility data sets. For the case of including only European baselines, during the final hour of the EVN observation, the fitted sizes exhibited linear expansion, indicating that the measured sizes were dominated by the angular separation of the two components. The 6 hr EVN observation took place in a rising phase of an even larger 4 day long radio flare, implying that the ejection events were quite frequent and therefore continuous radio monitoring is necessary to correctly estimate the power of the transient jet. Combined with X-ray monitoring data, the radio quenching and subsequent flares/ejections were likely driven by instabilities in the inner hot accretion disk.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144488890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Candidate Spectral Lines at 6 and 15 MeV from GRB 200829A and GRB 160905A GRB 200829A和GRB 160905A 6 MeV和15 MeV的候选谱线

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade4b8

Tong-Lei Liao, Shuo Xiao, Shao-Lin Xiong, Yan-Qiu Zhang, Wang-Chen Xue, Jiao-Jiao Yang, Zheng-Huo Jiang, Shu-Xu Yi, Zhen Zhang and Shuang-Nan Zhang

{"title":"Candidate Spectral Lines at 6 and 15 MeV from GRB 200829A and GRB 160905A","authors":"Tong-Lei Liao, Shuo Xiao, Shao-Lin Xiong, Yan-Qiu Zhang, Wang-Chen Xue, Jiao-Jiao Yang, Zheng-Huo Jiang, Shu-Xu Yi, Zhen Zhang and Shuang-Nan Zhang","doi":"10.3847/2041-8213/ade4b8","DOIUrl":"https://doi.org/10.3847/2041-8213/ade4b8","url":null,"abstract":"The discoveries of the evolving spectral line in gamma-ray burst (GRB) 221009A provide valuable information for understanding its extreme physical environment and emission mechanisms. In this work, we perform a comprehensive search for 3941 GRBs recorded in the Fermi/Gamma-ray Burst Monitor (GBM) from 2008 July to 2025 February; although no confirmed spectral lines are found, two spectral line candidates at ∼15 and ∼6 MeV in GRB 160905A and GRB 200829A are identified, respectively. Interestingly, the latter’s rest-frame line energy ∼13 MeV at redshift z = 1.25 is similar to that of GRB 221009A at z = 0.151. If this is true, it implies that they may share a common physical origin, possibly linked to blueshifted electron–positron annihilation processes within relativistic jets. Finally, this comprehensive search reveals no >5σ significant line features across the GBM GRB sample, with only two candidates at ∼3σ level. These results place meaningful constraints on the peculiarity and possible origin of the spectral line observed in GRB 221009A.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144488894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correlations between Event Rates of Short Gamma-Ray Bursts and Star Formation Rates with/without Time Delay 有/无时间延迟时短伽马射线暴事件率与恒星形成率的相关性

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade1d0

X. Y. Du, Z. B. Zhang, W. C. Du, G. A. Li, Y. Liu and H. C. Liu

{"title":"Correlations between Event Rates of Short Gamma-Ray Bursts and Star Formation Rates with/without Time Delay","authors":"X. Y. Du, Z. B. Zhang, W. C. Du, G. A. Li, Y. Liu and H. C. Liu","doi":"10.3847/2041-8213/ade1d0","DOIUrl":"https://doi.org/10.3847/2041-8213/ade1d0","url":null,"abstract":"In this Letter, we systematically investigate the redshift and luminosity distributions as well as the event rates of short gamma-ray bursts (SGRBs) detected by Swift, Fermi, and Konus–Wind satellites. It is found that the distributions of redshift and luminosity of Fermi and Konus–Wind SGRBs are identical, and they obviously differ from those of Swift/Burst Alert Telescope (BAT) SGRBs. The luminosity distributions of SGRBs detected by diverse detectors can be uniformly fitted by a smoothly broken power-law function. The median luminosity of Swift SGRBs is about 1 order of magnitude smaller than that of Fermi/Gamma-ray Burst Monitor (GBM) or Konus–Wind SGRBs. We also compare the local event rates of Swift/BAT, Fermi/GBM, and Konus–Wind SGRBs and find that the local rate of Swift SGRBs is around 2 orders of magnitude larger than that of either Fermi or Konus–Wind SGRBs, while the latter two rates are comparable. The observed SGRB rates can be successfully fitted by a power law plus Gauss function. The SGRB rates of three kinds of detectors match the delayed/undelayed star formation rates (SFRs) well, except the delayed lognormal and/or Gaussian SFRs at higher redshift, and exceed all types of SFRs at lower redshifts of z < 1. After deducting the diverse SFR components from the SGRB rates, to our surprise, we notice that the remaining SGRB rates steeply decline with redshift in a power-law-like form, indicating that these SGRBs could emerge from the old star populations or compact binary star mergers.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"152 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144516011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Supermassive Black Holes Stripping a Subgiant Star Down to Its Helium Core: A New Type of Multimessenger Source for LISA 超大质量黑洞将一颗次巨星剥离至其氦核：LISA的一种新型多信使源

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade432

Aleksandra Olejak, Jakob Stegmann, Selma E. de Mink, Ruggero Valli, Re’em Sari, Stephen Justham and Taeho Ryu

{"title":"Supermassive Black Holes Stripping a Subgiant Star Down to Its Helium Core: A New Type of Multimessenger Source for LISA","authors":"Aleksandra Olejak, Jakob Stegmann, Selma E. de Mink, Ruggero Valli, Re’em Sari, Stephen Justham and Taeho Ryu","doi":"10.3847/2041-8213/ade432","DOIUrl":"https://doi.org/10.3847/2041-8213/ade432","url":null,"abstract":"Some stars orbiting supermassive black holes (SMBHs) are expected to undergo a gravitational wave (GW)–driven inspiral and initiate mass transfer on nearly circular orbits. However, the stability and duration of such phases remain unexplored. In this work, we focus on the evolution of a low-mass, radiative-envelope subgiant star being stripped by an SMBH. We find that such systems can undergo a long-lasting, stable mass transfer phase, even if none of the angular momentum of the transferred material returns to the orbit to counterbalance the GW-driven decay. We show an example where a 2 M⊙ subgiant is stripped before entering the Laser Interferometer Space Antenna (LISA) band and loses almost its entire hydrogen envelope. The remaining helium core undergoes a prolonged GW-driven inspiral, becoming a loud LISA source. If formed in our Galaxy, the system would be detectable for several hundred thousand years, ultimately reaching extreme signal-to-noise ratios of a million. Hydrogen shell flashes in the residual envelope cause temporary radial expansions of the stripped star. As a result, a few additional phases of rapid mass transfer occur at orbital periods of 20–30 hr. Eventually, the core possibly undergoes circular partial tidal disruption at an orbital period of ∼10 minutes, corresponding to a GW emission frequency of a few mHz. We estimate a chance of about 1% that such a detectable LISA source exists in our own Galactic center. The loud final GW transient may lead to a few detections reaching as far as ∼1 Gpc, including, e.g., the Abell clusters.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144516149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tides Tighten the Hycean Habitable Zone 潮汐收紧海洋宜居带

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade434

Joseph R. Livesey, Juliette Becker and Susanna L. Widicus Weaver

引用次数: 0

Thermodynamic Evolution of Flaring Loops with Nonlocal Thermal Transport 具有非局部热输运的燃烧环的热力学演化

The Astrophysical Journal Letters Pub Date : 2025-06-25 DOI: 10.3847/2041-8213/ade542

S. Belov, T. Parmenter, T. Arber, D. Kolotkov, F. Reale and T. Goffrey

{"title":"Thermodynamic Evolution of Flaring Loops with Nonlocal Thermal Transport","authors":"S. Belov, T. Parmenter, T. Arber, D. Kolotkov, F. Reale and T. Goffrey","doi":"10.3847/2041-8213/ade542","DOIUrl":"https://doi.org/10.3847/2041-8213/ade542","url":null,"abstract":"Hot solar coronal loops, such as flaring loops, reach temperatures where the thermal transport becomes nonlocal. This occurs when the mean-free-path of electrons can no longer be assumed to be small. Using a modified version of the Lare2d code, we study the evolution of flare-heated coronal loops under three thermal transport models: classical Spitzer–Härm (SH), a flux-limited (FL) local model, and the nonlocal Schurtz–Nicolaï–Busquet (SNB) model. The SNB model is used extensively in laser-plasma studies. It has been benchmarked against accurate nonlocal Vlasov–Fokker–Planck models and proven to be the most accurate nonlocal model that can be applied on fluid timescales. Analysis of the density–temperature evolution cycles near the loop apex reveals a distinct evolutionary path for the SNB model, with higher temperatures and lower densities than local models. During energy deposition, the SNB model produces a more localized and intense temperature peak at the apex due to heat flux suppression, which also reduces chromospheric evaporation and results in lower postflare densities. Extreme-ultraviolet emission synthesis shows that the SNB model yields flare light curves with lower peak amplitudes and smoother decay phases. We also find that nonlocal transport affects equilibrium loop conditions, producing hotter and more rarefied apexes. These findings emphasize the need to account for nonlocal conduction in dynamic solar phenomena and highlight the potential of the SNB model for improving the realism of flare simulations. FL conduction models cannot reproduce the results of nonlocal transport covered by the SNB model.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144488895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0