Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi*

Collaboration, Hitomi; Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steven W; Angelini, Lorella; Audard, Marc; Awaki, Hisamitsu; Axelsson, Magnus; Bamba, Aya; Bautz, Marshall W; Blandford, Roger; Brenneman, Laura W; Brown, Gregory V; Bulbul, Esra; Cackett, Edward M; Chernyakova, Maria; Chiao, Meng P; Coppi, Paolo S; Costantini, Elisa; de Plaa, Jelle; de Vries, Cor P; den Herder, Jan-Willem; Done, Chris; Dotani, Tadayasu; Ebisawa, Ken; Eckart, Megan E; Enoto, Teruaki; Ezoe, Yuichiro; Fabian, Andrew C; Ferrigno, Carlo; Foster, Adam R; Fujimoto, Ryuichi; Fukazawa, Yasushi; Furuzawa, Akihiro; Galeazzi, Massimiliano; Gallo, Luigi C; Gandhi, Poshak; Giustini, Margherita; Goldwurm, Andrea; Gu, Liyi; Guainazzi, Matteo; Haba, Yoshito; Hagino, Kouichi; Hamaguchi, Kenji; Harrus, Ilana M; Hatsukade, Isamu; Hayashi, Katsuhiro; Hayashi, Takayuki; Hayashida, Kiyoshi; Hell, Natalie; Hiraga, Junko S; Hornschemeier, Ann; Hoshino, Akio; Hughes, John P; Ichinohe, Yuto; Iizuka, Ryo; Inoue, Ha...

Abstract

The Hitomi Soft X-ray Spectrometer spectrum of the Perseus cluster, with ∼5 eV resolution in the 2–9 keV band, offers an unprecedented benchmark of the atomic modeling and database for hot collisional plasmas. It reveals both successes and challenges of the current atomic data and models. The latest versions of AtomDB/APEC (3.0.8), SPEX (3.03.00), and CHIANTI (8.0) all provide reasonable fits to the broad-band spectrum, and are in close agreement on best-fit temperature, emission measure, and abundances of a few elements such as Ni. For the Fe abundance, the APEC and SPEX measurements differ by 16%, which is 17 times higher than the statistical uncertainty. This is mostly attributed to the differences in adopted collisional excitation and dielectronic recombination rates of the strongest emission lines. We further investigate and compare the sensitivity of the derived physical parameters to the astrophysical source modeling and instrumental effects. The Hitomi results show that accurate atomic data and models are as important as the astrophysical modeling and instrumental calibration aspects. Substantial updates of atomic databases and targeted laboratory measurements are needed to get the current data and models ready for the data from the next Hitomi-level mission.

Citation

Collaboration, H., Aharonian, F., Akamatsu, H., Akimoto, F., Allen, S. W., Angelini, L., Audard, M., Awaki, H., Axelsson, M., Bamba, A., Bautz, M. W., Blandford, R., Brenneman, L. W., Brown, G. V., Bulbul, E., Cackett, E. M., Chernyakova, M., Chiao, M. P., Coppi, P. S., Costantini, E., …Raassen, A. (2018). Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi*. Publications of Astronomical Society of Japan, 70(2), Article 12. https://doi.org/10.1093/pasj/psx156

• Journal Article Type: Article
• Acceptance Date: Dec 13, 2017
• Online Publication Date: Apr 11, 2018
• Publication Date: Apr 11, 2018
• Deposit Date: May 31, 2018
• Publicly Available Date: May 31, 2018
• Journal: Publications of Astronomical Society of Japan
• Print ISSN: 0004-6264
• Electronic ISSN: 2053-051X
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 70
• Issue: 2
• Article Number: 12
• DOI: https://doi.org/10.1093/pasj/psx156
• Public URL: https://durham-repository.worktribe.com/output/1329854