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Last modified: 26 October 2016

URL: http://cxc.harvard.edu/ciao/bugs/sky2tdet.html

Bugs: sky2tdet


Caveats

# sky2tdet (CIAO): ERROR: no non-null/0/nan pixels are in the input image 

The most likely cause of this error is that the region and energy filter supplied to sky2tdet do not select any events:

unix% dmlist "evt2.fits[sky=region(ciao.reg)][energy=300:2000]" counts
0 

Workaround:

Adjust the energy filter for the WMAP to match that of your events. The range of event energies in the region can be found with dmstat:

unix% dmstat "evt2.fits[sky=region(ciao.reg)][cols energy]"
energy[eV]
min: 2231.7507324 @: 61
max: 7980.6259766 @: 35
mean: 4012.0070413
sigma: 1252.6216735
sum: 429284.75342
good: 107
null: 0

Last modified: 26 October 2016
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