CALDB Public Release Notes Version 1.8 CALDB Date: 2000-11-20T17:00:00 AP/CP Date: 2000-11-20T17:00:00 I. CHANGES We have included an update to the LETG/HRC-S "bowtie" region filter, to correct an error in the BACKSCAL values, where an inverted value had originally been installed. In four rows of the data, the BACKSCAL value has been changed from the incorrect value of 0.2 to the correct value of 5.0. The error resulted from a misconversion of values in the grating coordinate system. The HRC-S tgmask2 CALDB file is applicable to ALL LETG/HRC-S observations from launch date. The new file is letgD1999-07-22regN0002.fits Version 1.8.1: CALDB date: 2000-12-07T14:25:00 AP/CP date: 2000-12-07T14:25:00 Added OSIP v4 files to the processing CALDB. These were already released with CALDB 2.0 on 12/4/2000, with CIAO 2.0. However these files serve double duty, requiring implementation in the pipelines to do proper order-sorting in tg_resolve_events, grating pipeline L1.5. FILENAMES: (Dates correspond to programmatice ACIS focal plane temperature resets.) acisD1999-07-22osipN0004.fits (-90C) acisD1999-08-13osipN0004.fits (-100C) acisD1999-09-16osipN0004.fits (-110C) acisD2000-01-29osipN0004.fits (-120C) II. DATA AFFECTS TGMASK2 update (LETG/HRC-S): Data processed after DATE=2000-11-20T17:00:00 (AP or REPRO) will use the new tgmask2 file in the LETGS grating Level 2 (TG_EXTRACT) pipeline, and the new BACKSCAL value will appear in the pha2.fits files. Data processed with dates before the above date will not get the correction, and Dave Huenemoerder is working on a data fix for those previous process results. Version 1.8.1 OSIP update: The version 4 files make a more appropriate cut for each of the chips at -110C and -120C. The N0002 files have too narrow a set of limits for -120C; the cut-off sigma has been increased to 4. There were problems with the -110C BI chip data (considerable noise in the responses) in acisD1999-09-16osipN0002.fits which needed correction as well. The AP/CP date is the same as the CALDB date, and any data processed with DATE before 2000-12-07T14:25:00 will NOT have these corrections in the OSIP files used in processing. The user will want to run tg_resolve_events (L1.5) with one of these files (depending on temperature of ACIS during their OBSID), and then repeat tg_extract (L2) to generate a new PHA2 file, using CIAO 2.x. For those whose data is processed after this date, there is no need to repeat the L1.5 and L2 because one of these files will already have been used during SDP. Users can also check for ASCDSVER. ASCDSVER=R4CU5UPD12.3 and after will have had acess to these new files. Earlier ASCDSVER values will not have these corrections, and tg_resolve_events and tg_extract should be re-run by the users, using CIAO 2.x.