Laboratory studies on a spherically curved Bragg spectrometer for cosmic X-ray spectroscopy
Abstract
A spherical array of twenty LiF 200 crystals was built to test the performances of a freestanding, self-focussing spherical crystal cosmic X-ray spectrometer. Measurements presently available show that the size of the image for a point source at infinite distance would be 3 mm (FWHM) along the focalisation axis and 2.1 mm (FWHM) along the dispersion axis. The mosaic spread on individual crystals is less than 0.1 degree. A slightly systematic deviation from the ideal bending (0.1 degree) is observed at the edges of most crystals and this appears to be the major limitation to spectrometer performance.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- November 1981
- Bibcode:
- 1981STIN...8226082C
- Keywords:
-
- Bragg Angle;
- Cosmic X Rays;
- Crystal Optics;
- Diffraction;
- Spaceborne Astronomy;
- X Ray Spectroscopy;
- Bending;
- Focusing;
- Imaging Techniques;
- Lithium Fluorides;
- Optical Properties;
- Spheres;
- Instrumentation and Photography