_version_ 1866917883678818304
author Fudamoto, Yoshinobu
Sun, Fengwu
Diego, Jose M.
Dai, Liang
Oguri, Masamune
Zitrin, Adi
Zackrisson, Erik
Jauzac, Mathilde
Lagattuta, David J.
Egami, Eiichi
Iani, Edoardo
Windhorst, Rogier A.
Abe, Katsuya T.
Bauer, Franz Erik
Bian, Fuyan
Bhatawdekar, Rachana
Broadhurst, Thomas J.
Cai, Zheng
Chen, Chian-Chou
Chen, Wenlei
Cohen, Seth H.
Conselice, Christopher J.
Espada, Daniel
Foo, Nicholas
Frye, Brenda L.
Fujimoto, Seiji
Furtak, Lukas J.
Golubchik, Miriam
Hsiao, Tiger Yu-Yang
Jolly, Jean-Baptiste
Kawai, Hiroki
Kelly, Patrick L.
Koekemoer, Anton M.
Kohno, Kotaro
Kokorev, Vasily
Li, Mingyu
Li, Zihao
Lin, Xiaojing
Magdis, Georgios E.
Meena, Ashish K.
Niemiec, Anna
Nabizadeh, Armin
Richard, Johan
Steinhardt, Charles L.
Wu, Yunjing
Zhu, Yongda
Zou, Siwei
author_facet Fudamoto, Yoshinobu
Sun, Fengwu
Diego, Jose M.
Dai, Liang
Oguri, Masamune
Zitrin, Adi
Zackrisson, Erik
Jauzac, Mathilde
Lagattuta, David J.
Egami, Eiichi
Iani, Edoardo
Windhorst, Rogier A.
Abe, Katsuya T.
Bauer, Franz Erik
Bian, Fuyan
Bhatawdekar, Rachana
Broadhurst, Thomas J.
Cai, Zheng
Chen, Chian-Chou
Chen, Wenlei
Cohen, Seth H.
Conselice, Christopher J.
Espada, Daniel
Foo, Nicholas
Frye, Brenda L.
Fujimoto, Seiji
Furtak, Lukas J.
Golubchik, Miriam
Hsiao, Tiger Yu-Yang
Jolly, Jean-Baptiste
Kawai, Hiroki
Kelly, Patrick L.
Koekemoer, Anton M.
Kohno, Kotaro
Kokorev, Vasily
Li, Mingyu
Li, Zihao
Lin, Xiaojing
Magdis, Georgios E.
Meena, Ashish K.
Niemiec, Anna
Nabizadeh, Armin
Richard, Johan
Steinhardt, Charles L.
Wu, Yunjing
Zhu, Yongda
Zou, Siwei
contents 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.
format Preprint
id arxiv_https___arxiv_org_abs_2404_08045
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Identification of $>$40 gravitationally magnified stars in a galaxy at redshift of 0.725
Fudamoto, Yoshinobu
Sun, Fengwu
Diego, Jose M.
Dai, Liang
Oguri, Masamune
Zitrin, Adi
Zackrisson, Erik
Jauzac, Mathilde
Lagattuta, David J.
Egami, Eiichi
Iani, Edoardo
Windhorst, Rogier A.
Abe, Katsuya T.
Bauer, Franz Erik
Bian, Fuyan
Bhatawdekar, Rachana
Broadhurst, Thomas J.
Cai, Zheng
Chen, Chian-Chou
Chen, Wenlei
Cohen, Seth H.
Conselice, Christopher J.
Espada, Daniel
Foo, Nicholas
Frye, Brenda L.
Fujimoto, Seiji
Furtak, Lukas J.
Golubchik, Miriam
Hsiao, Tiger Yu-Yang
Jolly, Jean-Baptiste
Kawai, Hiroki
Kelly, Patrick L.
Koekemoer, Anton M.
Kohno, Kotaro
Kokorev, Vasily
Li, Mingyu
Li, Zihao
Lin, Xiaojing
Magdis, Georgios E.
Meena, Ashish K.
Niemiec, Anna
Nabizadeh, Armin
Richard, Johan
Steinhardt, Charles L.
Wu, Yunjing
Zhu, Yongda
Zou, Siwei
Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
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.
title Identification of $>$40 gravitationally magnified stars in a galaxy at redshift of 0.725
topic Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2404.08045