日本天文学会2005年春季年会 [W03c]
○宮崎聡、常田佐久、中屋秀彦、山田亨、家正則、海部宣男(国立天文台)、谷口義明(東北大)、 土居守、岡村定矩(東大)、池田優二、武山芸英(ジェネシア)、海道宣明、山口耕司(オービタル)、 Colin Norman、Holland Ford、JeffKruk (JHU)、大内正巳(STScI)、Robert Woodruf (Locheed Martin)
Very Wide Field Imager (VWFI) is a planned mosaic CCD camera which is one of onboard instruments
on Hubble Origins Probe (HOP) together with other two science instruments COS and WFC3.
VWFI consists of 59 2K×2K CCDs occupying > 2 quadrants ofthe HOP focal plane with off-axis aberration corrector optics.
The astigmatism corrector optics consists of a pair of simple fused-silicaprisms optimized and dedicated to each CCD.
The FOV of VWFI is 175.5 square-arcmin, and the HOP OTA with the corrector delivers stable and high Strehl-ratio
images with a 0.05 arcsec CCD pixel size over the wide field of view. CCDs are cooled down to -80℃ with a mechanical
cooling system and an external dedicated radiator. The fully-depleted CCDs to be provided by Hamamatsu Photonics have
a demonstrated capability of high quantum efficiency approx. 0.7 at 1 micron. The very high efficiency at red wavelengths
makes VWFI exceptionally qualified to pursue the above science drivers. Multiple optimized filters either allocated
to each CCDs or with the mechanical filter wheels allow multi-color imaging.
VWFI is currently being studied with US-Japan working group under the auspices of the NASA Origins Probes Study.
VWFI is expected to be primarily provided by Japan.
