CALDB PUBLIC RELEASE NOTES Version: 2.1 CALDB effective date: 2000-12-21T19:00:00 Release date: NOT RELEASED TO THE PUBLIC CALDB 2.1 includes changes relevant only to the OBIDET L0.5 (observation interval determination) pipeline, which only runs with Standard Data Processing (SDP). For all sky observations, this upgrade is totally transparent and ineffectual. Only non-sky observations are to be handled differently as a result of these changes. See technical details below in Section II. "Sound and fury, signifying nothing." - Ayn Rand The new files in CALDB 2.1 will be included in CALDB 2.2 and higher versions, but have zero affect on CIAO or other tools. I. Summary of Changes OBSERVATION INTERVAL (OBI) TOLERANCES FILES CALDB implementation of OBI Tolerances (determination of intervals and relevant pipelines to run for a given set of Level 0 data. No new tolerances are specified herein. LOCATION: $CALDB/data/chandra/tel/bcf/otol/ FILENAMES: telD1999-07-23otolsN0001.fits telD1999-07-23otols_secN0001.fits SOFTWARE/PIPES/TOOLS affected: SDP OBIDET L0.5 Threads affected: NONE II. Technical Details OBI TOLERANCES (OBI_TOL) The obi_tolerances ARDs are the first CALDB compatible release of these data. In prior versions of the data system, a single obi_tolerances ARD was used from the $ASCDS_DATA directly, and not accessed via he CALDB. The ObI determination pipeline (OBIDET) identifies the actual data interval in telemetry that corresponds to the planned observation. The obi_tolerances ARD specifies the criteria used to match the actual and predicted spacecraft configuration data for this process. Ian Evans, as of 2000-12-19: As part of the CALDB implementation we have split the obi_tolerances ARD into two separate files to handle two separate processing threads. The first thread (observations on the sky) is the same as before, and the corresponding obi_tolerances file (telD1999-07-23otolsN0001.fits) has the same content as the previous implementation, except that it is updated with the necessary keywords for integration into the CALDB. For the second thread (non-sky observations; primarily calibration data eg, CTI measurements) we have modified the corresponding obi_tolerances file (telD1999-07-23otols_secN0001.fits) so that the state of the transmission gratings is not used in the matching criteria - since for such observations the state of the grating is not relevant for this purpose. This file also is updated with the necessary keywords for integration into the CALDB.