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The HRI detector performance is characterized by several parameters. These are the field of view, the detector quantum efficiency, the window transmission, the sources of background, the spatial and temporal resolution, and overall detector plus electronics event capacity. These properties are briefly summarized in Table 4.3 gif and are discussed in more detail in the following sections. Values of the quantum efficiency and background quoted here are based on in-flight and ground performance of the HRI.


Field of View 38' (square)
Spatial Resolution 1.7'' (FWHM)
Quantum Efficiency 30 percent at 1 keV
Window Transmission 75 percent at 1 keV
Background tex2html_wrap_inline2000 internal
(counts arcmin tex2html_wrap_inline1930  s tex2html_wrap_inline1894 ) tex2html_wrap_inline2006 external tex2html_wrap_inline2008
tex2html_wrap_inline2010 XRB tex2html_wrap_inline2012
tex2html_wrap_inline2014 Typical Total
Temporal Resolution 61 tex2html_wrap_inline1892 s
Dead Time 0.36 to 1.35 ms
Table 4.3:   ROSAT HRI Performance Summary

tex2html_wrap_inline2008 Depending upon orbital location. tex2html_wrap_inline2012 Depending upon viewing direction.

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