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The Boron filter

The filter only covers the region of the image within the central ring. The region outside is totally unfiltered and therefore should NOT be used as background for a source within the ring.

NB: There is currently a problem with analysing sources outside the central ring in images which have been filtered. The software currently treats these sources as though they have been filtered. A workaround is to type,

  > hmodify filename.more.asterix.instrument.filter val="OFF"

before correcting the file with XRTCORR.

This data exterior to the filter was only provided by some early versions of the SASS.

Next: Time series analysis Up: XRT ROSAT Prev: The HRI