from Gaensler on wavdetect positions

From: Belinda Wilkes (belinda@head-cfa.harvard.edu)
Date: Mon Oct 14 2002 - 22:15:12 EDT


Date: Mon, 14 Oct 2002 11:27:13 -0400 (EDT)
Cc: bgaensler@cfa.harvard.edu (Bryan Gaensler)
From: Bryan Gaensler <bgaensler@cfa.harvard.edu>
Organisation: Harvard-Smithsonian Center for Astrophysics
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Dear Chandra users,

There has been some discussion on this list in the past about the
accuracy of positional determinations for point sources as a function
of off-axis angle.

Has anyone explored whether the difference between the true position of
a source and that given by WAVDETECT can be decomposed into two
components: a random error and a systematic offset? In other words, is
there a distortion map which can be applied to ACIS data, which
corrects for a systematic bias in the positions of sources as a
function of off-axis angle, energy and signal-to-noise? Or are the
errors in off-axis positions entirely random in nature?

regards,
        
Bryan Gaensler

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  Harvard/Smithsonian email: belinda@cfa.harvard.edu
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