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Last modified: 26 October 2016

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

Bugs: tg_resolve_events


Table of Contents

Caveats


Caveats

# tg_resolve_events (CIAO): The following error occurred 38950 times:
  WARNING: Event chip position is outside of valid range. 
  Grating coordinates not computed for this event.

The warning indicates that some of the events chip coordinates are outside of the valid range, so tg_resolve_events cannot compute grating coordinates for them. It may be ignored, as long as the number of events outside the valid range is a small fraction of the total number of events in the file. For example:

unix% dmlist hrc_evt1.fits blocks
 
--------------------------------------------------------------------------------
Dataset: hrc_evt1.fits blocks
--------------------------------------------------------------------------------
 
     Block Name                          Type         Dimensions
--------------------------------------------------------------------------------
Block    1: PRIMARY                        Null        
Block    2: EVENTS                         Table        20 cols x 5866359  rows
Block    3: GTI                            Table         2 cols x 18       rows

(38950 / 5866359) * 100 = 0.663955

Since there are 5866359 events in the file, the 38950 for which grating coordinates were not computed make up just 0.66% of the total events.

# tg_resolve_events (CIAO): The following error occurred 10000 times:
  dsTREUNKNOWNINCOLERR -- WARNING: Not loading data from unrecognized level 1.5 input column.

The tool encountered a column in the input file that it does not recognize, and it is ignoring it when reading the file. Users who have applied the ACIS time-dependent gain correction will see this warning because of the PHA_RO column that is created in the reprocessed level=1 event file. This column is not used by any tools after acis_process_events, so the warning may be safely ignored.


Last modified: 26 October 2016
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