CALDB RELEASE NOTES Version: 2.17 CALDB Effective Date: 2002-10-01T13:00:00 PUBLIC RELEASE DATE: 2002-10-01, 09:00 EDT I. Summary of Changes I.A. ACIS Series "C" background files version 2 For Observation dates: 2000-01-29T20:00:00 to 2000-12-01T00:00:00 In $CALDB/data/chandra/acis/bcf/bkgrnd/ Seven new files: acis1sD2000-01-29bkgrndN0002.fits acis236sD2000-01-29bkgrndN0002.fits acis57sD2000-01-29bkgrndN0002.fits acis7iD2000-01-29bkgrndN0002.fits acis7sD2000-01-29bkgrndN0002.fits acis8sD2000-01-29bkgrndN0002.fits acisiD2000-01-29bkgrndN0002.fits These replace the following V1 files, which will no longer be distributed with the CALDB: acis0iD2000-01-29bkgrndN0001.fits acis1iD2000-01-29bkgrndN0001.fits acis1sD2000-01-29bkgrndN0001.fits acis23sD2000-01-29bkgrndN0001.fits acis2iD2000-01-29bkgrndN0001.fits acis2sD2000-01-29bkgrndN0001.fits acis3iD2000-01-29bkgrndN0001.fits acis3sD2000-01-29bkgrndN0001.fits acis57sD2000-01-29bkgrndN0001.fits acis5sD2000-01-29bkgrndN0001.fits acis6iD2000-01-29bkgrndN0001.fits acis6sD2000-01-29bkgrndN0001.fits acis7iD2000-01-29bkgrndN0001.fits acis7sD2000-01-29bkgrndN0001.fits acis8sD2000-01-29bkgrndN0001.fits acisiD2000-01-29bkgrndN0001.fits The decision to remove these from the distribution is for the sake of saving space. Individual CALDB managers may elect to keep the V1 files online, though they will be marked BAD in the ACIS CALDB index. I.B. HETG/ACIS-S LSF Parameter Files, v3 In $CALDB/data/chandra/tel/grating/hetg/cpf/lsf/ (Indexed in the acis index file.) Filenames: acisheg1D1999-07-22lsfparmN0003.fits acismeg1D1999-07-22lsfparmN0003.fits I.C. HRC-I Quantum Efficiency Version 6 In $CALDB/data/chandra/hrc/bcf/qe/ Filename: hrciD1999-07-22qeN0006.fits Replaces file: hrciD1999-07-22qeN0005.fits I.D. LETG/HRC-S Grating ARFs version 4 In $CALDB/data/chandra/tel/grating/letg/cpf/arf/ (Indexed in the hrc branch file.) Filenames: hrcsletg0D1999-07-22arfN0004.fits hrcsleg-1D1999-07-22arfN0004.fits hrcsleg1D1999-07-22arfN0004.fits Files replaced: hrcsletg0D1999-07-22arfN0003.fits hrcsleg-1D1999-07-22arfN0003.fits hrcsleg1D1999-07-22arfN0003.fits I.E. HRC-S Quantum Efficiency version 6 In $CALDB/data/chandra/hrc/bcf/qe/ Filename: hrcsD1999-07-22qeN0006.fits File replaced: hrcsD1999-07-22qeN0005.fits I.F. LETG/HRC-S Encircled Energy ARFs (EEARFs) In $CALDB/data/chandra/tel/grating/letg/cpf/arf/ Filenames: hrcsleg1D1999-07-22eearfN0002.fits hrcsleg-1D1999-07-22eearfN0002.fits Files replaced: hrcsleg1D1999-07-22eearfN0001.fits hrcsleg-1D1999-07-22eearfN0001.fits ---------------------------------------------------------------------- II. Technical Details This section provides technical information and URLs to CAL web pages relevant to the data in the new CALDB files in question. II.A. ACIS Series "C" background event lists version 2 The 2000-01-29 to 2000-12-01 period ACIS background files have been updated and condensed. The most significant change is that the compilations of blank-sky fields now allow better modeling of Galactic soft X-ray excess/deficiency from source observations. In particular, for ACIS-S, pointings toward North Polar Spur are now excluded, with a couple of others added instead. The same sets of observations are now used for different chips as much as possible, so that one can try modeling the Galactic soft excess/deficiency w.r.t. these background files using the outlying regions of the FOV. For BI chips, the light curve is now cleaned using the 2.5-7 keV band (was 0.3-10 kev). Holes left after the source exclusion are filled similarly to the earlier period D2000-12-01 files. See the contributed ACIS background web site at http://cxc.harvard.edu/contrib/maxim/acisbg/ Pipes/Software/Tools affected: CIAO/acis_project_events Threads affected: "ACIS Background Subtraction (Blank-Sky Files)" http://cxc.harvard.edu/ciao/threads/acisbackground/ II.B. HETG/ACIS-S LSF Parameter Files, version 3 The method for determination line-spread-function parameters has been completely overhauled and a new set of values for both HEG and MEG have been compiled. The method of derivation still uses Capella calibration data. The procedure is to extract lines at a large range of wavelengths, symmetrically about the peak, with extraction regions corresponding to four different encircled energy fractions; These extracted regions are fit to two Gaussians (peaks) and two Lorentzians (wings), to derive fitted function parameters. These parameters are valid for: 1) Point sources. 2) Symmetric extraction regions about a peak. 3) Extraction regions >> ACIS pixel scale. 4) Pixel randomization at 0.5 pixels included. 5) For +1st order; seem to be valid for -1st order also. 6) Optimized for the nominal aimpoint. Pipes/Software/Tools affected: CIAO/mkgrmf Threads affected: "Create Grating RMFs for ACIS-S Observations" http://cxc.harvard.edu/ciao/threads/mkgrmf_aciss/ II.C. HRC-I Quantum Efficiency Version 6 A more realistic model for the HRC-I QE below 0.63 keV has been included, along with a minor tweak to the Carbon edge of the UVIS-I filter transmission. The MCP QE, a plot of which is available at http://cxc.harvard.edu/cal/Hrc/Flight/mcp_qe_i.v2.1.jpg includes much more low-energy structural detail, which has been derived with the aid of HRC-S MCP QE flight calibration results. Pipes/Software/Tools affected: CIAO/mkinstmap Threads affected: "Compute an HRC-I Exposure Map and Build Fluxed Image" http://cxc.harvard.edu/ciao/threads/expmap_hrc/ "Compute LETG/HRC-I Grating ARFs" http://asc.harvard.edu/ciao/threads/mkgarf_letghrci/ II.D. LETG/HRC-S Grating ARFs version 4 New calibration data for the LETG/HRC-S effective area have been released as of July 2002. The results are posted on the LETGS Effective area Web page at http://cxc.harvard.edu/cal/Links/Letg/User/Hrc_QE/ea_index.html An internal memo discussing the results in more detail is located at http://icxc.harvard.edu/cal/oldcal/LETG_results/EA/Memo_0207/memo_ea_0207.html (CXC only, password required). Existing HRMA, Grating efficiency, LETG bowtie extraction region, and HRC-S QE uniformity data were used in the analysis and development. The model now includes improvements were made over the energy range .15 to 6 keV, including: - better high energy response in the 1-6 keV range - modeling CsI M edges at 0.75 keV - required small shift of the UVIS C-K edge amounting to -0.25 eV - better joining of the low-E WD calibration to the mid-E AGN calibration at ~ .15 keV. Pipes/Software/Tools affected: CIAO/Sherpa Threads affected: "Fitting Grating Data in Sherpa" http://cxc.harvard.edu/ciao/threads/sherpa_grating/index.html II.E. HRC-S Quantum Efficiency version 6 Concurrent with the new HRC-S/LETG effective areas, a new corresponding mean QE for HRC-S has been released. There is a new model, version 3, of the HRC-S MCP QE, and a small tweak to the UVIS-S transmissions at the Carbon edge (version 4). See the HRC web pages for the MCP QE S, and the UVIS-S transmissions at: http://cxc.harvard.edu/cal/Hrc/mcp_qe.html (version 3 file) and http://cxc.harvard.edu/cal/Hrc/uvis_trans.html#uvis-s (version 4 files) Pipes/Software/Tools affected: CIAO/mkgarf, mkinstmap Threads affected: "Compute LETG/HRC-S Grating ARFs" http://cxc.harvard.edu/ciao/threads/mkgarf_letghrcs/ II.F. LETG/HRC-S Encircled Energy ARFs (EEARFs) version 2 The N0001 versions of the EEARFs have an error in that the -1 order file contains the wrong data; it has exactly the same data in it as the +1 order file, instead of the slightly asymmetric values prescribed in the ASCII table on the LETGS EA web page. See specifically that web page http://cxc.harvard.edu/cal/Links/Letg/User/Hrc_QE/ea_index.html#first and the ASCII EEARF file: http://asc.harvard.edu/cal/Links/Letg/User/Hrc_QE/EA/extract_effic/letg_extract_effic_bowtie.dat The FITS EEARF files at the above links are now correct; the +1 is unchanged, -1 has corrected data. We shall update version on both to avoid user confusion in identifying them. Pipes/Software/Tools affected: CIAO/Sherpa Threads affected: "Fitting Grating Data in Sherpa" http://cxc.harvard.edu/ciao/threads/sherpa_grating/index.html