Soft X-ray Spectrometer

Model of the SXS module for Astro-H
Schematic drawing of the SXS detector module. The detector housing for the XCS is at the top of the drawing; the rest of the module houses the electronics and cooling system.

The Soft X-ray Spectrometer (SXS) is a system of X-ray calorimeters (the X-ray Calorimeter Spectrometer, or XCS) that sit behind an X-ray telescope (the Soft X-ray Telescope, or SXT). XCS is a spectrometer, an instrument that separates light signals into different frequencies, producing a spectrum.

A calorimeter works by detecting tiny temperature changes. When an incoming X-ray is absorbed in the detector, the detector heats up a tiny, tiny amount. In order to detect such a tiny temperature different, the detector will have be very cold – it will run at 50 milli-Kelvin, or 50 thousandths of a degree above absolute zero. Read more about this type of detector on our X-ray calorimeter page.

The SXS calorimeter will have 32 pixels and will detect X-rays in the range of 0.3 to 12 keV.