THE GAS IMAGING SPECTROMETER ON BOARD ASCA

Authors
OHASHI T EBISAWA K FUKAZAWA Y HIYOSHI K HORII M IKEBE Y IKEDA H INOUE H ISHIDA M ISHISAKI Y ISHIZUKA T KAMIJO S KANEDA H KOHMURA Y MAKISHIMA K MIHARA T TASHIRO M MURAKAMI T SHOUMURA R TANAKA Y UEDA Y TAGUCHI K TSURU T TAKESHIMA T
Citation
T. Ohashi et al., THE GAS IMAGING SPECTROMETER ON BOARD ASCA, Publications of the Astronomical Society of Japan, 48(2), 1996, pp. 157
Citations number
15
Categorie Soggetti
Astronomy & Astrophysics
Journal title
Publications of the Astronomical Society of Japan → ACNP
ISSN journal
00046264
Volume
48
Issue
2
Year of publication
1996
Database
ISI
SICI code
0004-6264(1996)48:2<157:TGISOB>2.0.ZU;2-8
Abstract
The Gas Imaging Spectrometer (GIS) system on board ASCA is described. The experiment consists of 2 units of imaging gas scintillation propor tional counters with a sealed-off gas cell equipped with an imaging ph ototube. The performance is characterized by the high X-ray sensitivit y (from 0.7 keV to over 10 keV), good energy resolution (7.8% FWHM at 6 keV following E(-0.5) as a function of X-ray energy E), moderate pos ition resolution (0.5 mm FWHM at 6 keV with E(-0.5) dependence), fast time resolution down to 61 mu s, and an effective area of 50 mm diamet er. The on-board signal processing system and the data transmitted to the ground are also described. The background rejection efficiency of the GIS is reaching the level achieved by the non-imaging multi-cell p roportional counters.