The XRISM/Resolve View of the Fe K Region of Cyg X-3
Authors:   XRISM Collaboration, Audard Marc , Awaki Hisamitsu , Ballhausen Ralf , Bamba Aya , Behar Ehud , Boissay-Malaquin Rozenn , Brenneman Laura , Brown Gregory V. , Corrales Lia , Costantini Elisa , Cumbee Renata , Díaz Trigo María , Done Chris , Dotani Tadayasu , Ebisawa Ken , Eckart Megan E. , Eckert Dominique , Eguchi Satoshi , Enoto Teruaki , Ezoe Yuichiro , Foster Adam , Fujimoto Ryuichi , Fujita Yutaka , Fukazawa Yasushi , Fukushima Kotaro , Furuzawa Akihiro , Gallo Luigi , García Javier A. , Gu Liyi , Guainazzi Matteo , Hagino Kouichi , Hamaguchi Kenji , Hatsukade Isamu , Hayashi Katsuhiro , Hayashi Takayuki , Hell Natalie , Hodges-Kluck Edmund , Hornschemeier Ann , Ichinohe Yuto , Ishida Manabu , Ishikawa Kumi , Ishisaki Yoshitaka , Kaastra Jelle , Kallman Timothy , Kara Erin , Katsuda Satoru , Kanemaru Yoshiaki , Kelley Richard , Kilbourne Caroline , Kitamoto Shunji , Kobayashi Shogo , Kohmura Takayoshi , Kubota Aya , Leutenegger Maurice , Loewenstein Michael , Maeda Yoshitomo , Markevitch Maxim , Matsumoto Hironori , Matsushita Kyoko , McCammon Dan , McNamara Brian , Mernier François , Miller Eric D. , Miller Jon M. , Mitsuishi Ikuyuki , Mizumoto Misaki , Mizuno Tsunefumi , Mori Koji , Mukai Koji , Murakami Hiroshi , Mushotzky Richard , Nakajima Hiroshi , Nakazawa Kazuhiro , Ness Jan-Uwe , Nobukawa Kumiko , Nobukawa Masayoshi , Noda Hirofumi , Odaka Hirokazu , Ogawa Shoji , Ogorzalek Anna , Okajima Takashi , Ota Naomi , Paltani Stephane , Petre Robert , Plucinsky Paul , Porter Frederick S. , Pottschmidt Katja , Sato Kosuke , Sato Toshiki , Sawada Makoto , Seta Hiromi , Shidatsu Megumi , Simionescu Aurora , Smith Randall , Suzuki Hiromasa , Szymkowiak Andrew , Takahashi Hiromitsu , Takeo Mai , Tamagawa Toru , Tamura Keisuke , Tanaka Takaaki , Tanimoto Atsushi , Tashiro Makoto , Terada Yukikatsu , Terashima Yuichi , Tsuboi Yohko , Tsujimoto Masahiro , Tsunemi Hiroshi , Tsuru Takeshi , Uchida Hiroyuki , Uchida Nagomi , Uchida Yuusuke , Uchiyama Hideki , Ueda Yoshihiro , Uno Shinichiro , Vink Jacco , Watanabe Shin , Williams Brian J. , Yamada Satoshi , Yamada Shinya , Yamaguchi Hiroya , Yamaoka Kazutaka , Yamasaki Noriko , Yamauchi Makoto , Yamauchi Shigeo , Yaqoob Tahir , Yoneyama Tomokage , Yoshida Tessei , Yukita Mihoko , Zhuravleva Irina , Tomaru Ryota , Hayashi Tasuku , Hakamata Tomohiro , Miura Daiki , Koljonen Karri , McCollough Mike 
Published: December 2024

Abstract
The X-ray binary system Cygnus X-3 (4U 2030+40, V1521 Cyg) is luminous but enigmatic owing to the high intervening absorption. High-resolution X-ray spectroscopy uniquely probes the dynamics of the photoionized gas in the system. In this Letter, we report on an observation of Cyg X-3 with the XRISM/Resolve spectrometer, which provides unprecedented spectral resolution and sensitivity in the 2–10 keV band. We detect multiple kinematic and ionization components in absorption and emission whose superposition leads to complex line profiles, including strong P Cygni profiles on resonance lines. The prominent Fe xxv Heα and Fe xxvi Lyα emission complexes are clearly resolved into their characteristic fine-structure transitions. Self-consistent photoionization modeling allows us to disentangle the absorption and emission components and measure the Doppler velocity of these components as a function of binary orbital phase. We find a significantly higher velocity amplitude for the emission lines than for the absorption lines. The absorption lines generally appear blueshifted by ∼−500–600 km s−1. We show that the wind decomposes naturally into a relatively smooth and large-scale component, perhaps associated with the background wind itself, plus a turbulent, denser structure located close to the compact object in its orbit.