CALDB Release Notes Version 2.5 CALDB DATE (TT): 2001-05-15T17:59 (13:58 EDT) Released to the Public on 2001-06-04. I. Summary of Changes A. ACIS OSIP (order sorting tables) FILENAMES FP_TEMP CVSD (eff. date) acisD1999-09-16osipN0005.fits -110C 1999-09-16T00:00:00 acisD2000-08-11osipN0005.fits -110C 2000-08-11T00:00:00 acisD2000-01-29osipN0005.fits -120C 2000-01-29T20:00:00 acisD2000-08-12osipN0005.fits -120C 2000-08-12T22:00:00 B. HETG/ACIS-S Grating RMF's (GRMF's) FILNAMES TG ORDER TG TYPE acisheg1D1999-07-22rmfN0004.fits 1 HEG acisheg2D1999-07-22rmfN0004.fits 2 HEG acisheg3D1999-07-22rmfN0004.fits 3 HEG acismeg1D1999-07-22rmfN0004.fits 1 MEG acismeg2D1999-07-22rmfN0004.fits 2 MEG acismeg3D1999-07-22rmfN0004.fits 3 MEG C. LETG/ACIS-S Grating RMF: acisleg1D1999-07-22rmfN0001.fits 1 LEG D. LETG/HRC-S Grating RMF's: hrcleg1D1999-07-22rmfN0002.fits 1 LEG hrcleg2D1999-07-22rmfN0002.fits 2 LEG hrcleg3D1999-07-22rmfN0002.fits 3 LEG hrcleg4D1999-07-22rmfN0002.fits 4 LEG hrcleg5D1999-07-22rmfN0002.fits 5 LEG hrcleg6D1999-07-22rmfN0002.fits 6 LEG II. Technical Details A. OSIP files updates: The only thing that changes here is to include data points at 0.1 keV and 11.0 keV in the OSIP files for -110C and -120C ACIS FP temperatures. Until now, there has been a problem for LETG/ACIS-S OBSIDs, in that tg_extract would get a truncated first order spectrum, because tg_resolve_events (L1.5 pipeline tool) would have no events included below 0.277 keV, (44.76A) the lower limit of the N0002 and N0004 OSIP files. This upgrade to N0005 files removes the truncation in L1.5 which appears in the pha2.fits files (in SDP or CIAO) beyond 44.76 angstroms in LETG/ACIS-S observations (only). Zero affect on the HETG/ACIS OBSIDs. USERS: All data processed with CALDBVER 2.4 or earlier will have the truncation error for wavelengths beyond 44.76A in the LEG first orders for LETG/ACIS-S Observations. Hence those OBSIDs should be reprocessed using the CIAO 2.1 thread "Obtain Grating Spectra from LETG/ACIS Data" http://asc.harvard.edu/ciao/threads/spectra.letgacis.html. The selection of the correct upgraded OSIP files will be automatic in tg_resolve_events. All data processed with CALDBVER = 2.5 or later will NOT have this problem, and do not need CIAO 2.1 reprocessing to fix it. This upgrade also affects the grating ARF's for LETG/ACIS and HETG/ACIS configurations. See the threads at http://asc.harvard.edu/ciao/threads/mkgarf.hetgacis.html http://asc.harvard.edu/ciao/threads/mkgarf.letgacis.html B. Improved canned HETG/ACIS-S GRMF's: These are the first Chandra Grating RMF's that may be used in Sherpa fitting for profiling analysis of lines. They are also the first accurately to describe the baseline continuum in the calibration data due to the mirror scatter. These RMF's have been built to agree with HETG Calibration data by using Gaussian (line) and Lorentzian (mirror scatter) components to model the CAL data. As such they represent accurate instrumental responses for the HETG/ACIS-S configuration. The CIAO threads page will be under development to include instructions on the use of these files in Sherpa in the coming weeks. These files will also be necessary for generating commensurate-grid grating ARF's with mkgarf. See the thread for this at http://asc.harvard.edu/ciao/threads/mkgarf.hetgacis.html C. Canned LETG/ACIS-S GRMF (1st order only): There is finally an approved LETG/ACIS-S grating RMF for the first order, useful for proposal planning simulations and for mkgarf (mkgarf_acis script), for LETG/ACIS-S observations. See http://asc.harvard.edu/ciao/threads/mkgarf.letgacis.html This GRMF is basically representative of the true instrument response, and as such is recommended for use in Sherpa for line profiling work in the first order only. It includes Gaussian and Lorentzian components in the modeling; however improvements in the long-wavelength portion of the model would be desirable at this point, as problems remain in that region. D. LETG/HRC-S GRMF's (1-6 orders) We have upgraded GRMF's now, and an extension in orders for the LETG/HRC-S configuration. These are useful for proposal planning purposes, but not for Sherpa modeling at this point. They are useful for generating grating RMF's using the CIAO thread at http://asc.harvard.edu/ciao/threads/mkgarf.letghrcs.html Warning: The effective area information in the CALDB for HRC-S (specfically the quantum efficiency) is in need of an upgrade. See http://asc.harvard.edu/caldb/update_schedule.html for details. This GRMF is not quite representative of the true instrument response, and as such is not recommended for use in Sherpa for line profiling work. It does include Gaussian and Lorentzian components in the modeling; however improvements in the model are required to make it an accurate RMF for fitting. LETG response model improvements are an ongoing task for CAL and Science Data Systems Planning groups at the CXC. Users will be advised with improved LETG GRMF's are developed and available. NOTE: The Grating RMF's in B, C, and D above are for on-axis, nominal aimpoint observations only. They are not specific to any particular observations, which requires the use of the CIAO tool mkrmf, which is still under development and not publicly released.