Verifying the HETG spectrometer Rowland design
Abstract
The HETGS on AXAF is the coordinated operation of the AXAF High-Resolution Mirror Assembly (HRMA), the high-energy transmission grating (HETG), and the grating-readout array of the AXAF CCD Imaging Spectrometer (ACIS-S). XRCF calibration data are analyzed to verify the Rowland geometry design of the HETGS. In particular, ACIS-S imaging of quadrant shutter focus test is used to probe the focus, alignment, and astigmatism of the spectra produced by diffraction through the high and medium energy gratings of the HETG. The experimental results are compared to expected values and to results obtained with the AXAF simulator, MARX.
- Publication:
-
X-Ray Optics, Instruments, and Missions
- Pub Date:
- November 1998
- DOI:
- 10.1117/12.331261
- Bibcode:
- 1998SPIE.3444...36S