The X-ray Imaging Spectrometer
There are four XIS detectors on Suzaku, each using a charge-coupled
device (CCD) to detect
the X-rays. These CCDs convert the X-ray photon into a cloud of
electrons, where the total charge of the cloud is proportional to the
X-ray energy. This cloud is moved (by voltages applied to the chip)
in bucket-brigade fashion across the CCD chip and measured at the end as
an electric charge. The charge measurement gives you a very accurate
estimate of the energy of the original X-ray. Each CCD consists of 1024
x 1024 pixels, and is about 25 mm on a side. Each one covers a region
on the sky 18 arc minutes x 18 arc minutes.
Each XIS detector is at the focal point of its own XRT.
The four Suzaku X-ray Imaging Spectrometers. (Click for larger view.)
Publication Date: June 2005