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Mirror Areas


Figure 4.2 gif shows the areas (in cm tex2html_wrap_inline1870 ) of the ROSAT mirror assembly as a function of energy for various off-axis angles (0', 20', 40', and 60'); obstruction by the telescope support structure has been included. The mirror areas do not vary much with energy except for various dips due to gold absorption edges before declining rapidly above 1 keV.

 fig4-2 figure148


Mirror type Wolter I
Mirror material Zerodur
Reflective coating Gold
Number of shells 4 paraboloid and hyperboloid pairs
Field of view tex2html_wrap_inline1848 (diameter)
Geometric area 1141 cm tex2html_wrap_inline1870
Aperture diameter 84 cm
Focal length 240 cm
Focal Plane Scale Factor 11.64 tex2html_wrap_inline1892 m arcsec tex2html_wrap_inline1894
High energy cutoff tex2html_wrap_inline1896 keV
angular resolution tex2html_wrap_inline1898 half energy width (HEW)
Scattered power <3 percent at 1.5 keV (for single reflection)
Table 4.1:   X-ray Mirror Assembly Characteristics

Michael Arida
Tue Jun 11 16:18:41 EDT 1996