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Last modified: 7 December 2012

URL: http://cxc.harvard.edu/ciao/bugs/dmfilth.html

Bugs: dmfilth

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For detailed information and examples of running this tool, refer to the dmfilth ahelp file.

Table of Contents

Bugs

Bugs

When using POISSON method, the distribution varies from true Poisson distribution slightly.

This is only detectable with many (hundreds) of runs.

The DIST method assumes positive, integer counts  (15 Mar 2012)

The tool will fail if this method is used with exposure-corrected images or if there are negative pixels in the source or background regions. 

unix% dmstat "events.fits[sky=region(source.reg)]"
EVENTS_IMAGE(x, y)
    min:        -2.0534541607         @:        ( 4620.5 4868.5 )
    max:        63.77072525           @:        ( 4588.5 4876.5 )
cntrd[log] :    ( 5.7060806841 5.973494067 )
cntrd[phys]:    ( 4586.1486455 4876.2879525 )
sigma_cntrd:    ( 6.3023091173 6.8273372496 )
   good:        70 
   null:        40

Last modified: 7 December 2012
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