Characterization of the Astro-E2 X-ray spectrometer

We present the results of extensive characterization tests of the X-ray Spectrometer (XRS), which will be launched in 2005 as part of the Astro-E2 mission. The XRS will utilize a newly developed 2-D microcalorimeter array of 32 pixels that will provide a resolution of ∼6eV over the energy range 0.3-10keV. The detector is characterized by the energy scale and energy resolution, both of which vary with design and operating parameters. We have calibrated the gain scale and energy resolution over a range of operating parameters including bias voltage, temperature, and incident photon flux. We will present the response of the cumulative detector array as well as a measure of the uniformity of the individual pixels. One pixel is physically offset from the array and will be continuously illuminated by a radioactive source in-flight. We will show the accuracy with which this pixel can be used to monitor variations in the focal plane array. Finally, we have illuminated the array with a high-energy continuum source and measured the Hg absorption edges in order to characterize the absorption efficiency of the pixels.