Constraining gas motion and non-thermal pressure beyond the core of the Abell 2029 galaxy cluster with XRISM
M. Audard, Hisamitsu Awaki, Ralf Ballhausen, Aya Bamba, Ehud Behar, Rozenn Boissay-Malaquin, Laura Brenneman, G. V. Brown, Lía Corrales, E. Costantini, Renata Cumbee, María Díaz Trigo, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, D. Eckert, S. Eguchi, Teruaki Enoto, Yuichiro Ezoe, Adam Foster, Ryuichi Fujimoto, Yutaka Fujita, Y. Fukazawa, Kotaro Fukushima, Akihiro Furuzawa, Luigi Gallo, Javier A. García, Liyi Gu, M. Guainazzi, Kouichi Hagino, Kenji Hamaguchi, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Natalie Hell, Edmund Hodges‐Kluck, A. E. Hornschemeier, Yuto Ichinohe, Daiki Ishi, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, J. S. Kaastra, T. R. Kallman, Erin Kara, Satoru Katsuda, Yoshiaki Kanemaru, Richard L. Kelley, Caroline A. Kilbourne, Shunji Kitamoto, Shōgo Kobayashi, Takayoshi Kohmura, Aya Kubota, Maurice A. Leutenegger, Michael Loewenstein, Yoshitomo Maeda, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, D. McCammon, B. R. McNamara, François Mernier, Eric D. Miller, J. M. Mïller, Ikuyuki Mitsuishi, Misaki Mizumoto, Tsunefumi Mizuno, Koji Mori, K. Mukai, Hiroshi Murakami, R. F. Mushotzky, Hiroshi Nakajima, Kazuhiro Nakazawa, Jan‐Uwe Ness, Kumiko Nobukawa, Masayoshi Nobukawa, Hirofumi Noda, Hirokazu Odaka, Shoji Ogawa, Anna Ogorzałek, Takashi Okajima, Naomi Ota, S. Paltani, Robert Petre, Paul P. Plucinsky, F. S. Porter, K. Pottschmidt, Kosuke Sato, Toshiki Sato, Makoto Sawada, Hiromi Seta, M. Shidatsu, A. Simionescu, Randall K. Smith, Hiromasa Suzuki, Andrew E. Szymkowiak, H. Takahashi, Mai Takeo, Toru Tamagawa
Abstract
Abstract We report on a detailed spectroscopic study of the gas dynamics and hydrostatic mass bias of the galaxy cluster Abell 2029, utilizing high-resolution observations from XRISM Resolve. Abell 2029, known for its cool core and relaxed X-ray morphology, provides an excellent opportunity to investigate the influence of gas motions beyond the central region. Expanding upon prior studies that revealed low turbulence and bulk motions within the core, our analysis covers regions out to the scale radius $R_{2500}$ (670 kpc) based on three radial pointings extending from the cluster center toward the northern side. We obtain accurate measurements of bulk and turbulent velocities along the line of sight. The results indicate that non-thermal pressure accounts for no more than 2% of the total pressure at all radii, with a gradual decrease outward. The observed radial trend differs from many numerical simulations, which often predict an increase in non-thermal pressure fraction at larger radii. These findings suggest that deviations from hydrostatic equilibrium are small, leading to a hydrostatic mass bias of around 2% across the observed area.