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Last modified: 6 February 2012

URL: http://cxc.harvard.edu/ciao4.4/bugs/acis_find_afterglow.html

Bugs: acis_find_afterglow

Return to: Bug List Index

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

Table of Contents

Bugs

Bugs

If the event data have invalid exposure numbers, then the afterglows will have TIME=NaN. [New] (21 Dec 2011)

If the input event data have invalid exposure numbers (EXPNO<3), then the resulting afterglows will have TIME=NaN. These exposure numbers occur in observations affected by the threshold-plane (T-plane) latchup issue, which is noted in the comments section of the V&V report.

Workaround:

Filter the event data before running the afterglow tool. The valid ranges are EXPNO>=3 for timed mode data and EXPNO>=4 for continuous-clocking mode. 

unix% dmkeypar acisf00659_000N003_evt1.fits READMODE echo+
TIMED

unix% dmstat "acisf00659_000N003_evt1.fits[cols EXPNO]"
expno
    min:        2             @:        1 
    max:        3073          @:        754068 
   mean:        1478.2589949 
    sum:        1114783195 
   good:        754119 
   null:        0 

unix% dmcopy "acisf00659_000N003_evt1.fits[EXPNO>2]" acisf00659_expno_evt1.fits

On the rare occasions that there are two hot pixels adjacent to one another, the tool may not identify one of the hot pixels. [New] (06 Feb 2012)


Last modified: 6 February 2012
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