Inflight Calibration of the Hitomi Soft X-ray Spectrometer (2) Point Spread Function

Yoshitomo Maeda; Toshiki Sato; Takayuki Hayashi; Ryo Iizuka; Lorella Angelini; Ryota Asai; Akihiro Furuzawa; Richard Kelley; Shu Koyama; Sho Kurashima; Manabu Ishida; Hideyuki Mori; Nozomi Nakaniwa; Takashi Okajima; Peter J. Serlemitsos; Masahiro Tsujimoto; Tahir Yaqoob

doi:10.1093/pasj/psx146

arXiv · 1712.08321

Inflight Calibration of the Hitomi Soft X-ray Spectrometer (2) Point Spread Function

Yoshitomo Maeda·Toshiki Sato·Takayuki Hayashi·Ryo Iizuka·Lorella Angelini·Ryota Asai·Akihiro Furuzawa·Richard Kelley·Shu Koyama·Sho Kurashima·Manabu Ishida·Hideyuki Mori·Nozomi Nakaniwa·Takashi Okajima·Peter J. Serlemitsos·Masahiro Tsujimoto·Tahir Yaqoob

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Abstract

We present results of inflight calibration of the point spread function (PSF) of the Soft X-ray Telescope (SXT-S) that focuses X-ray onto the pixel array of the Soft X-ray Spectrometer system (SXS). We make a full array image of a point-like source by extracting a pulsed component of the Crab nebula emission. Within the limited statistics afforded by an exposure time of only 6.9~ksec and the limited knowledge of the systematic uncetainties, we find that the raytracing model of 1'.2 half-power-diameter (HPD) is consistent with an image of the observed event distributions across pixels. The ratio between the Crab pulsar image and the raytracing shows scatter from pixel to pixel that is 40% or less in all except one pixel. The pixel-to-pixel ratio has a spread of 20%, on average, for the 15 edge pixels, with an averaged statistical error of 17% (1 sigma). In the central 16 pixels, the corresponding ratio is 15% with an error of 6%.

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Yoshitomo Maeda, Toshiki Sato, Takayuki Hayashi, Ryo Iizuka, Lorella Angelini, Ryota Asai, Akihiro Furuzawa, Richard Kelley, Shu Koyama, Sho Kurashima, Manabu Ishida, Hideyuki Mori, Nozomi Nakaniwa, Takashi Okajima, Peter J. Serlemitsos, Masahiro Tsujimoto, Tahir Yaqoob. 2017-12-22. Inflight Calibration of the Hitomi Soft X-ray Spectrometer (2) Point Spread Function. https://doi.org/10.1093/pasj%2Fpsx146

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