GSE XOP -> Instrument

The XRS Instrument

XRS is a high-resolution, high-throughput X-Ray Spectrometer

 

The XRS instrument is a telescope for X-ray astronomy, using a new kind of detector which combines good spectral resolution with good collecting power (throughput). This is the first time this type of detector has flown on a satellite mission.

Resolution and collecting power are the two main goals of an X-ray instrument.

 

X-ray astronomy consists mainly of looking at spectra, and there are two main goals in making an instrument for X-ray astronomy:

  1. Spectral Resolution. The ideal X-ray astronomy instrument would have a resolution narrower than any atomic spectral features one might look at. That would be a fraction of an eV. Currently the best resolution is achieved by grating-type instruments.
  2. Collecting power. Most interesting X-ray sources in the sky are very dim (less than one X-ray photon per second per cm2). This means that X-ray telescopes need to have large apertures, and detectors need high quantum efficiency. This has meant solid-state detectors of one kind or another up to now.

The XRS detectors combine relatively high resolution (~10eV) with very high efficiency (~99%) for the first time. This will allow a whole new range of observations.

 

For more information

There is a set of pages about the XRS at the LHEA. The GSE deals with data from the Calorimeter Analog Processor (CAP), and the Calorimeter Digital Processor (CDP). There is currently no information about the CAP, but the CDP has some pages available.