In-orbit performance of the soft X-ray imaging system aboard Hitomi (ASTRO-H)
Abstract
We describe the in-orbit performance of the soft X-ray imaging system consisting of the Soft X-ray Telescope and the Soft X-ray Imager aboard Hitomi. Verification and calibration of imaging and spectroscopic performance are carried out making the best use of the limited data of less than three weeks. Basic performance including a large field of view of 38'x38' is verified with the first light image of the Perseus cluster of galaxies. Amongst the small number of observed targets, the on-minus-off pulse image for the out-of-time events of the Crab pulsar enables us to measure a half power diameter of the telescope as about 1.3'. The average energy resolution measured with the onboard calibration source events at 5.89 keV is 179 pm 3 eV in full width at half maximum. Light leak and cross talk issues affected the effective exposure time and the effective area, respectively, because all the observations were performed before optimizing an observation schedule and parameters for the dark level calculation. Screening the data affected by these two issues, we measure the background level to be 5.6x10^{-6} counts s^{-1} arcmin^{-2} cm^{-2} in the energy band of 5-12 keV, which is seven times lower than that of the Suzaku XIS-BI.
Cite
@article{arxiv.1709.08829,
title = {In-orbit performance of the soft X-ray imaging system aboard Hitomi (ASTRO-H)},
author = {H. Nakajima and Y. Maeda and H. Uchida and T. Tanaka and H. Tsunemi and K. Hayashida and T. G. Tsuru and T. Dotani and R. Nagino and S. Inoue and M. Ozaki and H. Tomida and C. Natsukari and S. Ueda and K. Mori and M. Yamauchi and I. Hatsukade and Y. Nishioka and M. Sakata and T. Beppu and D. Honda and M. Nobukawa and J. S. Hiraga and T. Kohmura and H. Murakami and K. K. Nobukawa and A. Bamba and J. P. Doty and R. Iizuka and T. Sato and S. Kurashima and N. Nakaniwa and R. Asai and M. Ishida and H. Mori and Y. Soong and T. Okajima and P. Serlemitsos and Y. Tawara and I. Mitsuishi and K. Ishibashi and K. Tamura and T. Hayashi and A. Furuzawa and S. Sugita and T. Miyazawa and H. Awaki and E. D. Miller and H. Yamaguchi},
journal= {arXiv preprint arXiv:1709.08829},
year = {2018}
}
Comments
Accepted for publication in PASJ. 17 pages, 18 figures