Measurements Of X-Ray Scattering From Wolter Type Telescopes and Various Flat Zerodur Mirrors

Full beam X-ray tests of high angular resolution have been performed on two of MPI's 32 cm Wolter type I telescopes. Scattering levels are in agreement with those obtained earlier by pencil beam tests. Due to the higher angular resolution of the full beam tests the central core of the point spread function has been resolved. It shows a width of 6 arcsec FWHM and a half power radius of ≈ 30 arcsec. The large half power radius can be attributed to axial slope errors of the mirrors. 9 superpolished, flat mirror samples made of Zerodur have been subjected to extensive X-ray scattering measurements at λλ 13.3 Å, 8.3 Å, 2.8 Å, and 1.9 Å and grazing angles from 15 arcmin to 150 arcmin. The scattered intensity has been recorded out to 4- 20 arcmin off the specular direction. Two components differing in width can be distinguished in the line spread function: 1. a broad component, which can be understood in terms of standard scattering theories; 2. a narrow component, appearing within ± 5 areminofthe central peak. Some hypotheses for the origin of the narrow component will be discussed.