CalDB PUBLIC Release Notes
Version: 3.4.0
Effective Date: 2007-05-16T15:00:00

I. Introduction

CalDB 3.4.0 is a significant upgrade over all preceding versions of the Chandra Calibration Database. It includes improvements to the following areas:

    1) ACIS T_GAIN Epochs 28 & 29 (November 2006 - April 2007)
    2) ACIS/MEG 1st-order LSF parameters
    3) ACIS/HETG and ACIS/LETG optional dispersion mask files for use in CIAO 4beta1
    4) Modified boundary conditions for response inputs to mkacisrmf for BI chips without CTI correction
    5) New ACIS blank-sky background event lists
    6) HRC-I Time-dependent GMAPs version N0002
    7) HRC-S QE with improved Oxygen K-edge features

The ACIS BKGRND blank-sky files are packaged separately as has been our usual procedure. See the CIAO/CALDB downloads page for more information, Additionally, to reduce the size of the CalDB 3.4.0 upgrade tar ball, we have reinitiated the cumulative upgrades with this release. This implies that if your site has not upgraded the local CalDB with version 3.3.0 or, then you must use the "main", not the "upgrade", tar ball to install CalDB 3.4.0.

II. Summary of Changes

A. ACIS T_GAIN upgrades for EPOCH 28 & 29 (Nov. 06 - April '07)
    Location: $CALDB/data/chandra/acis/bcf/t_gain/
    Filenames:    acisD2006-08-01t_gainN0005.fits
    The ACIS external calibration source (ECS) data taken in the radiation zone during the 01-Nov-2006 through 31-Jan-2007 period has been reduced and analyzed for the T_GAIN corrections for all FI chips with CTI correction applied, and for BI chips for both CTI-corrected and non-CTI-corrected cases. The first two files above apply to the case of CTI_APP='PPPPPNPNPP', that is, where the parallel CTI correction has been applied to only the FI chips, and none to the BI chips.

    The 3rd and 4th files apply for the CTI_APP case 'PPPPPBPBPP', where all ten ACIS chips are CTI corrected to the fullest extent available, parallel CTI correction for the FI chips, and both serial and parallel to the BI's.

PIPES/TOOLS affected:
CIAO and Standard Processing (SDP) ACIS L1 tool acis_process_events, parameters apply_cti and cti_file.

THREADS affected:

"Creating a new ACIS L2 events file"
"Applying the ACIS time-dependent gain correction"

B. ACIS Blank-Sky BKGRND events lists
   Unpacking Location: $CALDB/data/chandra/acis/bcf/bkgrnd/
   Filenames: See $CALDB/data/chandra/acis/bcf/bkgrnd/acis_bkgrnd_manifest.txt
       for a table of files, CCD_ID's, and other relevant
       information. Sixty-six files in all are included.

ACIS Blank-sky files in the CalDB have been upgraded to be equivalent to the latest files in Maxim Markevitch's contributed experimental background files web page, These files include four epochs of Chandra ACIS Background, including those for -100C focal plan operation (1999-08-12 to 1999-09-16), -110C (1999-09-16 to 2000-01-29), and two epochs for -120C (2000-01-29 to 2000-12-01, and 2000-12-01 to the present).  CTI-corrected background files with T_GAIN correction applied are included for chips 0-3 and 6. No BI CTI-corrected data for ACIS-5 or ACIS-7 are included at this time, though they are forthcoming in a future release.

CIAO tools affected:

CIAO Threads affected:
"Using the ACIS "Blank-Sky" Background Files"

C. HRC-S QE version N0009
   Location: $CALDB/data/chandra/hrc/bcf/qe/

Modified oxygen K-edge structure for all three plates, approximately 10% affect at 545 eV.

CIAO Tools affected
mkexpmap (mkinstmap), mkgarf with LETG/HRC-S

CIAO Threads affected:
"Compute LETG/HRC-S Grating ARFs"

D. HRC-I Time-Dependent GMAPs version N0002
   Location: $CALDB/data/chandra/hrc/bcf/gain/

SDP/CIAO pipeline/tool affected
    HRC L1 pipeline and CIAO reprocessing tool hrc_process_events

CIAO Threads affected:

"Create a New Level=2 Event File" 

E. ACIS-S/MEG 1st Order LSF Parameters for mkgrmf version N0005 (TG_RAND=0.0)
   Location: $CALDB/data/chandra/tel/grating/hetg/cpf/lsf/

These files will produce a more appropriately narrow GRMF for MEG/ACIS-S.

CIAO tools affected: mkgrmf

CIAO threads affected:
"Create Grating RMFs for HRC Observations"
F. ACIS-S/Grating DISP_REG files: Secondary TGMASK files for tgextract2
   Location: $CALDB/data/chandra/acis/bcf/disp_reg/

CIAO 4Beta1 tools affected: tgextract2

CIAO Threads Affected:
To be released later!

G. Correction to the P2_RESP N0005 BI chip SC_MATRIX header
   Location: $CALDB/data/chandra/acis/cpf/p2_resp/
   Filename: acisD2000-01-29p2_respN0005.fits
   (File already released in CalDB 3.0.0, December, 2004. Header
   modifications only to boundary conditions, to add an additional
   case for which the file may be selected from the index.)

CIAO tools affected: mkacisrmf and related scripts (psextract, acisspec, specextract)
    when analyzing ACIS-5 and ACIS-7 data, uncorrected for CTI, only.

CIAO Threads affected:
"Creating ACIS RMFs with mkacisrmf" 

H. PCAD ALIGN/FID_POS files version N0006
   Location: $CALDB/data/chandra/pcad/bcf/align/
   Filenames: pcadD<yyyy-mm-dd>alignN0006.fits
              where yyyy-mm-dd = CVSD0001, or Calibration Validity
                    Start Date.
These new files have no affect whatever on CIAO users. They are used in SDP only. Two new epochs added (2003-06-09 and 2006-12-10) are added to correct for astrometric errors which are believed to be due to cooling down of the ACA CCDs.

SDP Pipes/tools affected:
ASPECT L1 pipeline

- Dale