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CDA - News Item 040

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News Item 040

Update on CDFS 2010 Data


Due to a problem with bad pixel processing in one of the 2010 CDFS observations (ObsId 12218), a small percentage of its events were improperly omitted in the CDFS merged dataset released on 20 August 2010, with Chandra Announcement 61. This involved almost 6000 events (out of 200,000) with Time > 392706012, CCD_ID = 0, and CHIPY > 512.
A corrected event file for ObsId 12218 was released on 1 September 2010, identified by "N002". The 2010 and 2000-2007-2010 merged products were also regenerated, identified as "N002", and released on the same date.

We caution that the problem may occur for this ObsId (12218) if a user re-runs acis_build_badpix or acis_run_hotpix (which calls acis_build_badpix), for example following the CIAO bad pixel science thread.

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Last modified: 2010-12-22

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