Examining the angular resolution of the ASTRO-H’s soft x-ray telescopes

Sato, Toshiki; Iizuka, Ryo; Ishida, M.; Kikuchi, Naomichi; Maeda, Yoshitomo; Kurashima, Sho; Nakaniwa, Nozomi; Tomikawa, Kazuki; Hayashi, Takayuki; Mori, Hajime; Okajima, Takashi; Serlemitsos, P. J.; Soong, Yang; Izumiya, Takanori; Minami, Sari

doi:10.1117/1.jatis.2.4.044001

Cited by 14 publications

(11 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These pixels detect light that was reflected from the reflectors near the quadrant boundaries and slipped through the gate valve criss-cross structure (see figure 3 ). The PSF properties of the reflectors near the quadrant boundaries are found to be more complex than those from the other reflectors (Sato et al 2016a). These facts may contribute to the large scatter between the Crab pulsar image and the raytracing output.…”

Section: Discussionmentioning

confidence: 93%

“…During the ground calibration, the image of the SXT-S was over-sampled by the CCD detector with a 22.5µm pixel size, which corresponds to ∼0. 7 (Sato et al 2016a). Using the image, the Encircled Energy Fraction, or EEF, was calculated as a function of radius, by deriving the energy enclosed by a circle of a given radius centered on the centroid, as a fraction of the energy enclosed within some normalising radius.…”

Section: Methods and Analysismentioning

confidence: 99%

“…Data for estimating the errors on ground were taken with the X-ray calibration facility at ISAS/JAXA (Hayashi et al 2015). The errors were examined with "spot scan" measurements (Sato et al 2014, Sato et al 2016a, in which we illuminate regions all over the aperture of each quadrant with a square beam 8 mm on a side. Based on the scan results, "maps" of image blurring and the focus position were made.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

In-flight calibration of the Hitomi Soft X-ray Spectrometer. (2) Point spread function

Maeda

Sato

Hayashi

et al. 2018

Publications of the Astronomical Society of Japan

Self Cite

View full text Add to dashboard Cite

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% (1σ). In the central 16 pixels, the corresponding ratio is 15% with an error of 6%.

show abstract

Section: Discussionmentioning

confidence: 93%

Section: Methods and Analysismentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

In-flight calibration of the Hitomi Soft X-ray Spectrometer. (2) Point spread function

Maeda

Sato

Hayashi

et al. 2018

Publications of the Astronomical Society of Japan

Self Cite

View full text Add to dashboard Cite

show abstract

“…In brief, events are graded either into H (high-), M (medium-), or L (lowresolution) for decreasing length to the closest events in time. Ground Sato et al 2016a;Iizuka et al JATIS, submitted) and in-flight (Okajima et al 2016)…”

Section: Observationmentioning

confidence: 99%

“…Sato et al 2016a; Iizuka et al JATIS, submitted) and additional detailed measurements of the Au LMaeda et al 2016) and M edges. The Au L3 to L1 edges at 11.919, 13.734, and 14.353 keV and the M5 to M1 edges at 2.206, 2.291, 2.743, 3.148, and 3.425 keV are the most prominent features in the effective area curve of the Au-coated mirrors (figure 4f), which are also recognized in the actual spectrum (figure 4a).…”

mentioning

confidence: 98%

In-flight calibration of Hitomi Soft X-ray Spectrometer. (3) Effective area

Tsujimoto

Okajima

Eckart

et al. 2018

Publications of the Astronomical Society of Japan

Self Cite

View full text Add to dashboard Cite

We present the result of the in-flight calibration of the effective area of the Soft X-ray Spectrometer (SXS) onboard the Hitomi X-ray satellite using an observation of the Crab nebula. We corrected for the artifacts when observing high count rate sources with the X-ray microcalorimeter. We then constructed a spectrum in the 0.5-20 keV band, which we modeled with a single power-law continuum attenuated by an interstellar extinction. We evaluated the systematic uncertainty upon the spectral parameters by various calibration items. In the 2-12 keV band, the SXS result is consistent with the literature values in flux (2.20 ± 0.08 ×10 −8 erg s −1 cm −2 with a 1σ statistical uncertainty) but is softer in the power-law index (2.19 ± 0.11). The discrepancy is attributable to the systematic uncertainty of about +6/−7% and +2/−5% respectively for the flux and the power-law index. The softer spectrum is affected primarily by the systematic uncertainty of the Dewar gate valve transmission and the event screening.

show abstract