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arXiv 2404.08045astro-ph.GAastro-ph.CO
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在红移0.725的星系中识别出超过40颗受引力放大的恒星

Identification of $>$40 gravitationally magnified stars in a galaxy at redshift of 0.725

Yoshinobu Fudamoto, Fengwu Sun, Jose M. Diego, Liang Dai, Masamune Oguri, Adi Zitrin, Erik Zackrisson, Mathilde Jauzac, David J. Lagattuta, Eiichi Egami, Edoard… 展开作者

Yoshinobu Fudamoto, Fengwu Sun, Jose M. Diego, Liang Dai, Masamune Oguri, Adi Zitrin, Erik Zackrisson, Mathilde Jauzac, David J. Lagattuta, Eiichi Egami, Edoardo Iani, Rogier A. Windhorst, Katsuya T. Abe, Franz Erik Bauer, Fuyan Bian, Rachana Bhatawdekar, Thomas J. Broadhurst, Zheng Cai, Chian-Chou Chen, Wenlei Chen, Seth H. Cohen, Christopher J. Conselice, Daniel Espada, Nicholas Foo, Brenda L. Frye, Seiji Fujimoto, Lukas J. Furtak, Miriam Golubchik, Tiger Yu-Yang Hsiao, Jean-Baptiste Jolly, Hiroki Kawai, Patrick L. Kelly, Anton M. Koekemoer, Kotaro Kohno, Vasily Kokorev, Mingyu Li, Zihao Li, Xiaojing Lin, Georgios E. Magdis, Ashish K. Meena, Anna Niemiec, Armin Nabizadeh, Johan Richard, Charles L. Steinhardt, Yunjing Wu, Yongda Zhu, Siwei Zou

AI总结:

利用JWST时域观测在红移0.725的“龙弧”星系中发现超过40颗微透镜恒星,揭示高事件发生率并证明高红移恒星统计研究的可行性。

摘要:

强引力放大效应能够探测微弱背景源、分辨其内部结构,甚至识别遥远星系中的单颗恒星。被高度放大的单颗恒星具有多种应用,包括研究遥远星系中的恒星族以及约束透镜平面中的暗物质结构。然而,这些应用一直受到已观测到的单颗恒星数量较少的限制,通常每个遥远星系只能识别出一颗或几颗恒星。在此,我们报告利用詹姆斯·韦布空间望远镜(JWST)的时域观测技术,在Abell 370后方一个红移为0.725的星系(当时宇宙年龄约为当前年龄的一半,被称为“龙弧”)中发现了超过40颗微透镜恒星。这些事件出现在预期的透镜临界曲线附近,表明它们是被放大的恒星,表现为来自星系团内恒星微透镜的暂现源。通过多波段测光,我们约束了恒星类型,发现其中许多与红巨星/超巨星一致,放大倍数达数百倍。这一发现揭示了龙弧中前所未有的高微透镜事件发生率,并证明JWST的时域观测为开展高红移恒星的统计研究开辟了可能性。

英文摘要:

Strong gravitational magnifications enable to detect faint background sources, resolve their internal structures, and even identify individual stars in distant galaxies. Highly magnified individual stars allow various applications, including studies of stellar populations in distant galaxies and constraining dark matter structures in the lensing plane. However, these applications have been hampered by the small number of individual stars observed, as typically one or a few stars are identified from each distant galaxy. Here, we report the discovery of more than 40 microlensed stars in a single galaxy behind Abell 370 at redshift of 0.725 when the Universe was half of its current age (dubbed ``the Dragon arc''), using James Webb Space Telescope (JWST) observations with the time-domain technique. These events are found near the expected lensing critical curves, suggesting that these are magnified stars that appear as transients from intracluster stellar microlenses. Through multi-wavelength photometry, we constrain stellar types and find that many of them are consistent with red giants/supergiants magnified by factors of hundreds. This finding reveals an unprecedented high occurrence of microlensing events in the Dragon arc, and proves that {\it JWST}'s time-domain observations open up the possibility of conducting statistical studies of high-redshift stars.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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