next up previous contents
Next: SIS Up: Instruments Previous: Instruments

Telescope

A team from GSFC, Nagoya University and ISAS is providing the Astro-D telescope which consists of four identical sets of conical thin-foil nested mirrors. The design--already tested and flown in the BBXRT mission--combines high throughput and a wide energy band (0.3- 12 keV) with moderate spatial resolution (image size of 2.6 mm HPD giving an angular resolution of about 2.9 arcminutes); it also satisfies the severe size and weight constraints of the launch vehicle. In fact, in order to accommodate the telescope within the nose cone of the M-3S-II rocket, the optical bench of the mirror system will be extended after launch. The focal length of the telescope is 3500 mm; its inner and outer radii are 60 mm and 172 mm, respectively. The total effective area is 1000 cm^2 below 1 keV and is 500 cm^2 in the range 6-7 keV.

In the focal planes of the four sets of mirrors will be two Solid-state Imaging Spectrometers (SIS) and two Gas-scintillation Imaging Spectrometers (GIS), permanently installed.



Keith Arnaud
1/5/1998