CALDB Public Release Notes Version: 2.9 CALDB Effective Date: 2001-10-22T16:00:00 (11:58 EDT) With the coming release of CIAO 2.2 it is necessary to upgrade the Chandra CALDB to version 2.9. Several new tools require CALDB enhancements, including "mkgrmf", "reproject_events", and the ACIS and HRC L1 processing tools (PIXLIB upgrade). Therefore, you must download and install CALDB 2.9 (or upgrade from an earlier version) to run CIAO 2.2. I. SUMMARY OF CHANGES --------------------- A. PIXLIB "GEOM" version 4 FILENAME: $CALDB/data/chandra/tel/bcf/geom/telD1999-07-23geomN0004.fits The new file includes a more accurate representation of the telescope system geometry, including separate Rowland spacings for the HETG and LETG, as well as the corrected focal length for the HRMA. Use acis_process_events or hrc_process_events in CIAO 2.2 to implement the new file in your data. B. ACIS Background Events files, version 1 FILE LOCATION: $CALDB/data/chandra/acis/bcf/bkgrnd/ (new directory with 2.9) These are the CALDB implementation of the ACIS extended source background construction utilities that have been available from Maxim Markevitch on the swap page. These files are to be used by the new "reproject_events" routine in CIAO 2.2. NOTE: The ACIS background library adds approximately 223 MB to the size of the CALDB. C. HRC-I QE Uniformity (QEU) version 2 FILENAME: $CALDB/data/chandra/hrc/bcf/qe/hrciD1999-07-22qeuN0002.fits Implements the most recent HRC-I flat field measurements of the QE Uniformity into a correction map to be applied to HRC-I effective areas (mkarf) and HRC-I exposure maps (mkexpmap). D. HRC-S QE version 4 and QEU version 2 FILENAMES: $CALDB/data/chandra/hrc/bcf/qe/hrcsD1999-07-22qeN0004.fits $CALDB/data/chandra/hrc/bcf/qe/hrcsD1999-07-22qeuN0002.fits Allows the use of mkarf and mkgarf for HRC-S imaging or HRC-S/LETG grating observations. Replaces the need for canned ARFs or GARFs in these cases. E. LSF parameter files, version 1 FILENAMES: $CALDB/data/chandra/tel/grating/hetg/cpf/lsf/ acismeg1D1999-07-22lsfparmN0001.fits acisheg1D1999-07-22lsfparmN0001.fits $CALDB/data/chandra/tel/grating/letg/cpf/lsf/ hrcsleg1D1999-07-22lsfparmN0001.fits These files are necessary for the operation of "mkgrmf", newly released with CIAO 2.2. Now users can make their own grating RMFs for any order and any source position. F. Canned Grating RMFs File located in $CALDB/data/chandra/tel/grating/hetg or letg/cpf/rmf/ There is a minor change to all of the canned grating RMFs (GRMFs) in the CALDB. The HDUNAME for the principal extension has been changed to "MATRIX". This makes the files conform to the usual OGIP standard for RMFs. G. ACIS-I 2D_PSF file correction FILENAME: $CALDB/data/chandra/acis/cpf/2dpsf/acisi1998-11-052dpsf2N0002.fits This file has had a small header correction. II. Technical Details A. PIXLIB GEOM version 4 The new values are discussed on the internal web page http://icxc.harvard.edu/cal/platescale/geom11_test_030901.html The thread "Use the new GEOM.PAR (v4) file", located at http://asc.harvard.edu/ciao/threads/geom.par.thread.html instructs the use to implement the new file. NOTE: The Data System will not incorporate the new GEOM file for a few weeks from this release date, so CIAO reprocessing via this thread will be necessary to implement the new geometry data. B. ACIS Background Events files, version 1 The acis background and its subtraction are discussed on the CAL web page http://asc.harvard.edu/cal/Links/Acis/acis/Cal_prods/bkgrnd/current/index.html. To provide a means of subtracting a background from extended sources, where near-field background subtraction is not possible, certain event lists have been generated which may be convolved with any specific obseration's aspect solution to generate a suitable estimated background. These background events files are described in detail in the text: http://hea-www.harvard.edu/~maxim/axaf/acisbg/data/README The files contain event lists from specific blank-field observations, which have been cleaned of flares. They are specific to one or more ACIS chips, with either the ACIS-I or ACIS-S array positioned at the aimpoint. The naming convention used by Maxim Markevitch is as follows: acis[aimpoint]_[A,B,C]_chipid_bkg_evt_DDMMYY.fits where aimpoint position is either "i" or "s", depending on the SIM_Z value (which array is in the focal plane for these data, [A,B,C] gives the grouping corresponding to the temperature (A:-100C, B:-110C, and C:-120C) or the effective dates (A: SSD open to Sept 11, 1999, B: Sept 16, 1999-January 2000, and C: Feb 2000 - ). A fourth set may be added soon, effective Fall 2000, but is not included in this ECR. "chipid" is one of i0, i1, i2, i3, s0, s1, s2, s3, s4, s5, s6. For the CALDB, there is already a standard for filenames. Hence the background lists are named: acis#DYYYY-MM-DDbkgrndN0001.fits, where the date YYYY-MM-DD is the effective date of the file. For A files that is 1999-08-12, B 1999-09-16, and for C 2000-01-29. "#" is the integral specification for the chip, 0-9. The CIAO 2.2 tool "reproject_events" is used to implement background subtraction using these files. The THREAD which employs "reproject_events" is "ACIS Background Subtraction (Blank Sky files), located at http://asc.harvard.edu/ciao/threads/acisbackground.thread.html. C. HRC-I QE Uniformity (QEU) version 2 The HRC-I flat-field calibration maps posted at http://asc.harvard.edu/cal/Links/Hrc/CIP/Flight/FlatField/i_flat_details.html have been converted and renormalized into FITS format for use in CIAO exposure map and effective area software. ARDLIB in CIAO 2.2 will be expanded to include the new FITS file to be called automatically from the CALDB. The CIAO 2.2 thread "Compute an HRC-I Exposure Map and Build Fluxed Image", located at http://asc.harvard.edu/ciao/threads/expmap.hrc.html will employ this new file via the ARDLIB (ardlib.par) as a matter of course. D. HRC-S QE version 4 and QEU version 2 FOR HRC-S REFERENCE QE: The calibrations of the reference (on-axis) quantum efficiencies for HRC-S, including the pure MCP QEs and the UV/ion shield (UVIS) transmissions have been upgraded recently. The UVIS data are new as of 4/9/2001, and the new QE's are dated 5/15/2001. The CALDB "QE" files contain the multiplicative product of the UVIS transmission and the chip/plate QE. The new UVIS data (V3 files) are posted and illustrated on the CAL web page at http://asc.harvard.edu/cal/Links/Hrc/CIP/uvis_trans.html. The UVIS thickness varies with the structure, because of the HESF (high-energy suppression filter) structure. The structure is illustrated at that web page. The files with the specific data are at http://asc.harvard.edu/cal/Links/Hrc/CIP/SACpre/, with names uvis_s1.v3.mdl uvis_s2.v3.mdl uvis_s34.v3.mdl uvis_s56.v3.mdl See the full web page to view spatially how these data are to be applied. These new results include synchrotron transmission calibration data with improved edge structure definition. The new (on-axis) HRC-S MCP QE (V2) is posted and illustrated on the CAL web page at http://asc.harvard.edu/cal/Links/Hrc/CIP/mcp_qe.html. The specific data are at http://asc.harvard.edu/cal/Links/Hrc/CIP/Flight/mcp_qe_s.v2.mdl. The new QE's are derived from laboratory and flight flat field data analysis. FOR HRC-S QEU: The laboratory flat field data used to derive the HRC-S QEU are publicly posted at http://asc.harvard.edu/cal/Links/Hrc/CIP/flatfield.html#hrc-s, taken from flight measurments. HRC-S flat fields were acquired at seven energies (0.183, 0.277, 0.525, 0.852, 1.487, 4.511, 6.404 keV) in the HRC Lab prior to flight. These flats unavoidably included the UV/ion shield structure in the data. The data were binned up by 128 pixels (half-tap) for good statistics. HRC-S QE Uniformity was derived in the following way: The UV/ion shield was divided out of the HRC-S flat field measurements, leaving bare MCP QEs at seven energies. These were all normalized to the HRC-S nominal aimpoint. Only the nominal LETG dispersion strip (where the data from LETG nominal pointings would lie on the HRC-S) was extracted from the flats. This is because we have detailed source coverage of this region by calibration sources, for confirmation. However, we have very very limited coverage outside the nominal dispersion strip. Hence the new uniformity map includes no cross-dispersion variations. Instead, a grid spanning the full range of Chandra energies (0.06 - 12.0 keV) was then interpolated/extrapolated from the seven line energies, producing a linear HRC-S QEU along the array. The linear QEU was then replicated in the cross-dispersion dimension to produce a full QEU surface, applicable to any pointing of the HRC-S. The thread "Compute LETG/HRC-S Grating ARFs", updated for CIAO 2.2, employs these new files with the new "fullgarf" script to build LETG/HRC-S grating ARFs. This thread is located at: http://asc.harvard.edu/ciao/threads/mkgarf.letghrcs.html E. LSF parameter files, version 1 With the advent of CIAO 2.2 the new mkgrmf (make grating RMF) tool will be released mkgrmf requires the line-spread function (LSF) parameters to calculate the matrices. The parameters include those for Gaussian (lines) and Lorentzian (scattering tails) components of the HEG, MEG, and LEG grating parts, as functions of wavelength. These parameters have been used to generate the canned grating RMFs (GRMFs) released previously and still included in the CALDB. Those canned, on-axis GRMFs will remain in the CALDB; however with the addition of these three files, users will be able to generate observation-specific GRMFs for any order order of the HEG/ACIS-S and MEG/ACIS-S, as well as LEG/HRC-S, including an rmf specific to any wavelength grid or extraction region. The parameters have been used in mkgrmf to generate GRMFs which were then compared with Capella grating observations in the three configurations. These Gaussian and Lorentzian parameters were derived using MARX simulations to generate grating responses that most closely matched the LSF calibrations for HEG, MEG, and LEG. The HEG calibration data for this are located at http://space.mit.edu/HETG/technotes/ede_0102/ede_0102.html These data can be fitted well across the full range using the MARX model, and hence GRMFs generated with these values are good for fitting. The new CIAO 2.2 thread "Create Grating RMFs", located at http://asc.harvard.edu/ciao/threads/mkgrmf.thread.html, instructs the user in implementation of the mkgrmf tool, which uses these files automatically from the CALDB via the ARDLIB. F. Canned Grating RMFs The HDUNAME for all the files has been changed to MATRIX.