STScI Logo

Hubble Space Telescope
Calibration Product Review for the GHRS

  1. Introduction
  2. Calibration Process
  3. Summary of Reference Files
  4. File Descriptions
  5. Individual Reference Files
  6. Tables stored in CDBS but not used by CALHRS

(GHRS Instrument Science Report 067, Official Update)

Lisa E. Sherbert and S. J. Hulbert

This Report summarizes the status of calibrations and calibration reference files for the Goddard High Resolution Spectrograph. Each calibration file that is stored in the Calibration Database System (CDBS) is briefly described as well.

1. Introduction

The pipeline data reduction program, calhrs, determines how to calibrate a particular dataset by checking "switches" that are set to PERFORM or OMIT and by accessing various calibration reference files. These reference files were summarized in GHRS-ISR-067 Calibration Product Review for the GHRS in Early Cycle 4, by Hulbert, et al., but due to changes in calibration, this document needs to be continually updated. Up until now, we have been providing updates via the GHRS Calibration Resource pages on the World Wide Web. This is the latest version of that document, dated 06 Jun 1997, and it will be available on only on the WWW, initially.

This document contains a listing of all GHRS Reference Images and Tables that are presently available in the Calibration Data Base System (CDBS). The tables herein are intended to provide a history of the differences among the files and tables which were used by the pipeline to calibrate GHRS data. This Report provides a description of the files and their usage as of 06 June 1997, for the convenience of Archival HST users. A brief review of the calibration process and control switches is included here. Additional information on the usage of calhrs and the reference files may be found in HST Data Handbook, issued in December, 1995 and later.

2. Calibration Process

Figure 1 shows a flowchart of the calibration process followed by calhrs. In this diagram, the rectangles on the right-hand side contain the name of a calibration switch that "controls" a given calibration step. The performed calibration step is briefly described in the central rectangular box. The rounded boxes on the left contain the names of calibration reference files needed for a particular calibration step to be completed. Figure 2 is an example science data header, listing the header keywords that act as calibration "switches" as well as the list of calibration reference files used.

Figure 1: Calibration Flowchart

Figure 2: Calibration Flowchart (Continued)

Figure 3: Example Science Data Header File Showing Calibration Reference Files and Switches

                  / CALIBRATION REFERENCE FILES
DIOHFILE = 'zref$cce1504az.r0h' / diode response header file
PHCHFILE = 'zref$bcc11275z.r1h' / photocathode response header file
VIGHFILE = 'zref$e751116dz.r2h' / vignetting response header file
ABSHFILE = 'zref$e5v0936rz.r3h' / absolute flux header file
NETHFILE = 'zref$e5v0936az.r4h' / absolute flux wavelength net header file
DQIHFILE = 'zref$cce1505kz.r5h' / data quality initialization header file
SAAHFILE = 'zref$h5m1337dz.r6h' / SAA Contour Mask header file
CCR1     = 'ztab$aau13518z.cz1' / photocathode line mapping parameters table
CCR2     = 'ztab$ba412190z.cz2' / photocathode sample parameters table
CCR3     = 'ztab$c7f1130oz.cz3' / detector parameters table
CCR4     = 'ztab$a3d1045dz.cz4' / wavelength ranges table
CCR5     = 'ztab$e3u1417oz.cz5' / spectral order constants table
CCR6     = 'ztab$e3t1251bz.cz6' / dispersion constants table
CCR7     = 'ztab$e3t1250tz.cz7' / thermal constants table
CCR8     = 'ztab$e3t1250lz.cz8' / incidence angle coefficients table
CCR9     = 'ztab$e751042hz.cz9' / echelle interpolation constants table
CCRA     = 'ztab$e751041qz.cza' / echelle non-interpolation constants table
CCRB     = 'ztab$d8b1457az.czb' / scattered light correction factors
CCRC     = 'ztab$e3u14301z.czc' / global wavelength coefficients table
CCRD     = 'ztab$e3t1028nz.czd' / photocathode blemish table
CCRE     = 'ztab$h5m13378z.cze' / background count rate model
CCG2     = 'mtab$a3d1145ly.cmg' / paired-pulse correction table

                  / CALIBRATION SWITCHES
DQI_CORR = 'PERFORM           ' / data quality initialization
EXP_CORR = 'PERFORM           ' / division by exposure time
DIO_CORR = 'PERFORM           ' / diode response correction
PPC_CORR = 'PERFORM           ' / paired-pulse correction
MAP_CORR = 'PERFORM           ' / mapping function
DOP_CORR = 'OMIT              ' / doppler compensation
PHC_CORR = 'PERFORM           ' / removal of photocathode nonuniformity
VIG_CORR = 'PERFORM           ' / removal of vignetting nonuniformity
MER_CORR = 'PERFORM           ' / merging of substep bins
GWC_CORR = 'PERFORM           ' / use global wavelength coefficients
ADC_CORR = 'PERFORM           ' / application of dispersion constants
MDF_CORR = 'OMIT              ' / median filter of background spectra
MNF_CORR = 'OMIT              ' / mean filter of background spectra
PLY_CORR = 'PERFORM           ' / polynomial smoothing of background spectra
BMD_CORR = 'OMIT              ' / background model INSTEAD of bkgd spectra
BCK_CORR = 'PERFORM           ' / background removal
IAC_CORR = 'PERFORM           ' / incidence angle correction
ECH_CORR = 'PERFORM           ' / correction for echelle ripple
FLX_CORR = 'PERFORM           ' / absolute flux calibration
HEL_CORR = 'PERFORM           ' / conversion to heliocentric wavelengths
VAC_CORR = 'OMIT              ' / vacuum to air correction

3. Summary of Reference Files

Table 1 lists the 7 types of GHRS reference images and 15 types of GHRS reference tables contained in CDBS as well as 2 reference tables used for post-pipeline processing. Table 1 is organized by file format, the filename extension used to identify a given type of reference image or table, the name of the header keyword in the science data header that contains the actual name of the reference image or table used by the calibration software to calibrate the data, a short description of the reference image or table, and, where appropriate, the selection criterion used to differentiate among reference files of the same type.

4. File Descriptions

The summaries found in Tables 2 through 24 are grouped by the DESCRIPTION column in Table 1. Each existing reference image has listed the detector or grating for which this file is appropriate-reference tables are not differentiated in this manner since they contain data appropriate for all gratings or detectors. The date of its installation into CDBS, the USE_AFTER date, the source of the data (PEDIGREE), and a short description of why the file was updated is also given. The USE_AFTER date is an important feature of CDBS. This keyword allows for the proper time-tagging of reference files and tables. A given file or table with a particular USE_AFTER date should only be used to process data obtained on or after the USE_AFTER date-hence, the name. The PEDIGREE of a reference file or table indicates the source of the data. The permitted values for this parameter are:

GROUND means that pre-launch measurements were used to generate the reference data;

INFLIGHT means that measurements were collected with GHRS in orbit; and, MODEL means that the data are based on a model instead of measurements; DUMMY means that there is no reference data, instead the file or table contains all 1's or 0's and has no effect on calibration.

For internal tracking purposes we are now including from the CDBS-PODPS tracking forms, the initials of those persons who (submitted/verified/approved) the data. The slashes separate the different steps in the process of getting the data into the CDBS; information which is unavailable will be left blank. A list of full names corresponding to the initials used is available below:

Initials Person/Organization Initials Person
IDT Instrument Definition Team PL Paul Lee
MdlP Michele de la PeC1a HG Harry Garner
JDE Jonathan Eisenhamer DL Don Lindler
LF Laura Ferrarese CL Claus Leitherer
RLG Ron Gilliland MM Melissa McGrath
AMG Anne Gonnella ABS Al Schultz
SJH Steve Hulbert LES/MEW Lisa E. Sherbert
ML Matt Lallo DRS Dave Soderblom
HL Howard Lanning CT Calvin Tullos
JRM Jennifer Mack

4.1 Selecting the "Right" Images and Tables

Over the past several years a number of changes have been made to both the reference images and tables and the calibration software that employs them. In general, software changes are backwards-compatible with earlier versions of reference tables. However, this has not always been the case. Consequently, the current version of the software will not properly run with "old" data and/or "old" reference files. This is most likely to be a problem if one is using data from before 11 Nov 91 in its original form. The simplest work-around to any problem of this sort is to obtain officially processed data and the latest (appropriate) reference files and tables from the HST data archive. There are two methods by which one can identify the "best" reference files and tables to use when recalibrating GHRS data. 1) Use this document and compare it to your headers by hand. 2) Use the HST Data archive -the GHRS calibration file form in StarView provides a simple interface for identifying the "best" files.

File Format Filename Extension Header Keyword Description Selection Criterion
Files r0h DIOHFILE GHRS diode response files Detector
r1h PHCHFILE GHRS photocathode response files Grating
r2h VIGHFILE GHRS vignetting files Grating
r3h ABSHFILE GHRS absolute sensitivity files Grating
r4h NETHFILE GHRS wavelength net files Grating
r5h DQIHFILE GHRS data quality files Detector
r6h SAAHFILE SAA Contour Mask header file n/a
Tables cz1 CCR1 GHRS line mapping parameters n/a
cz2 CCR2 GHRS sample mapping parameters
cz3 CCR3 GHRS detector parameters
cz4 CCR4 GHRS wavelength ranges
cz5 CCR5 GHRS spectral order constants
cz6 CCR6 GHRS dispersion constants
cz7 CCR7 GHRS thermal constants
cz8 CCR8 GHRS incidence angle constants
cz9 CCR9 GHRS echelle ripple interpolation constants
cza CCRA GHRS echelle ripple non-interpolation constants
czb CCRB GHRS scale factors for scattered light subtraction
czc CCRC GHRS Global Wavelength Coefficients
czd CCRD GHRS Photocathode Blemish Location Table
cze CCRE GHRS Background Count Rate Model
cmg CCG2 Paired-pulse correction table
Tables czy Not used for pipeline processing PtNe Lamp Line List n/a
czz SSA Wavelength Offsets

5. Individual Reference Files

5.1 Diode Response Files (DIOHFILE).

The diodes within the Digicons of the GHRS do not have identical sensitivities. The diode response correction (controlled by DIO_CORR) divides the input data by diode response values (which are near unity). Applying a correction to the observed count rates is normally done in all cases. This file has changed with time because of threshold adjustment in a few diodes. Each detector has 512 diodes, the middle 500 of which are used for science.

FILE DET DATE USE_AFTER PEDIGREE COMMENT
8ck15001z.r0h 1 20 Dec 89 24 Apr 90 GROUND Initial delivery from IDT.
(DL/ML/RLG)
8ck15002z.r0h 2
aaj0926dz.r0h 1 19 Oct 90 24 Apr 90 INFLIGHT OV Data from IDT.
(RLG//RLG)
aaj0926oz.r0h 2
c551543az.r0h 2 07 May 92 20 Apr 92 INFLIGHT Thresholds adjusted for science diodes 80, 237, 273, and 441 (86, 243, 279, 447 out of 512) by STScI based on discussions w/HG.
(SJH/MEW/MEW)
cce1504az.r0h 2 15 Dec 92 21 Dec 92 INFLIGHT Set science diode 342 (348 out of 512) response to 0: turned off as of 92356 PHA test (PID 2851); based on discussions w/HG.
(SJH/MEW/MEW)
f511531az.r0h 2 12 Apr 95 15 May 95 INFLIGHT Science diode 237 (243/512) turned off as of 95135.
(LES/AG)
f5o1134cz.r0h 1 22 May 95 29 May 95 INFLIGHT Science diode 085 (091/512) turned off as of 95149.
(AG/LES)
g2e08350z.r0h 2 26 Feb 96 26 Feb 96 INFLIGHT Science diode 051 (057/512) turned off as of 96057.
(LES/DRS)

5.2 Photocathode Response Files (PHCHFILE).

The photocathode response correction (controlled by PHC_CORR) is included to allow for the removal of the granularity of the GHRS photocathodes to achieve high signal-to-noise. Presently, however, the GHRS does not use this feature because obtaining the flat-field exposures for all possible grating positions is impracticable for most gratings. Therefore the default pipeline image is a DUMMY file that is populated with ones and zeroes and the only changes made to the default since launch have been to correct mistakes and keep grating names up to date. However, in 1996, G140L flat filed files became available. Please see GHRS-ISR-076 for more details.

FILE GRATING DATE USE_AFTER PEDIGREE COMMENT
96t0914qz.r1h ECH-A 20 Dec 89 24 Apr 90 DUMMY Initial Delivery from IDT. WARNING: these files contain incorrect values in pixel 300.
(DL/ML/RLG)
96t0916lz.r1h G140L
96t0915gz.r1h G140M
96t09157z.r1h ECH-B
96t0915qz.r1h G160M
96t09167z.r1h G200M
96t0916ez.r1h G270M
aa916392z.r1h ECH-A 10 Oct 90 24 Apr 90 DUMMY NOTE: incorrect values in previous files have been corrected.
(RLG//RLG)
aa91640lz.r1h G140L
aa91639jz.r1h G140M
aa91639cz.r1h ECH-B
aa91639qz.r1h G160M
aa916401z.r1h G200M
aa91640az.r1h G270M
bcc1126sz.r1h ECH-A 12 Dec 91 24 Apr 90 DUMMY Same data. New grating names.
(CT//RLG)
bcc1127bz.r1h G140L
bcc11273z.r1h G140M
bcc11270z.r1h ECH-B
bcc11275z.r1h G160M
bcc11277z.r1h G200M
bcc11279z.r1h G270M
fbk1610nz.r1h ECH-A 29 Nov 95 24 Apr 90 DUMMY Updated to add PEDIGREE and DESCRIP keywords to alert user to DUMMY nature of these files.
(LES//LES)
fbk1610oz.r1h ECH-B
fbk1610pz.r1h G140M
fbk1610rz.r1h G160M
fbk1610sz.r1h G200M
fbk1610tz.r1h G270M
fbk16110z.r1h G140L
ga41342hz.r1h G140L LSA 04 Oct 96 04 Feb 94 INFLIGHT Post-COSTAR flatfields. For optional use with S/N>30 data. Use with CALHRS v.5.10 or higher. Not intended for pipeline. See GHRS-ISR-076.
(ABS//ABS)
ga41342iz.r1h G140L SSA
h3e1400fz.r1h G140L LSA 03 Apr 97 04 Feb 94 INFLIGHT Fixes previous 2 files by removing the INDEFs in first and last points (which put zeros in end-points of calibrated data.)
(ABS//LES)
h3e1400gz.r1h G140L SSA

5.3 "Vignetting" (VIGHFILE).

The response of the GHRS photocathode drops near its edges, producing an effect similar to optical vignetting, hence the name. This effect is calibrated by comparing similar spectra obtained at the center and edges of the photocathode. Setting VIG_CORR to PERFORM will correct for this phenomena.

FILE GRATING DATE USE_AFTER PEDIGREE COMMENT
8cl0946rz.r2h ECH-A 20 Dec 89 24 Apr 90 DUMMY Initial delivery from IDT.
(DL/ML/RLG)
8cl0948hz.r2h G140L
8cl0947pz.r2h G140M
8cl0947hz.r2h ECH-B
8cl09484z.r2h G160M
8cl09489z.r2h G200M
8cl0948dz.r2h G270M
b9i1428qz.r2h G140L 02 Oct 91 24 Apr 90 INFLIGHT SV data from IDT. New grating names.
(DL//RLG)
b9i14289z.r2h G140M
b9i1428ez.r2h G160M
b9i1428hz.r2h G200M
b9i1428mz.r2h G270M
bcc1126oz.r2h ECH-A 12 Dec 91 24 Apr 90 DUMMY New Grating names.
(CT//CT)
bcc1126qz.r2h ECH-B
d9u0950mz.r2h G160M 30 Sep 93 24 Apr 90 INFLIGHT Deleted 1st 2 groups from previous version because they lead to bad calibration. The groups deleted correspond to the short wavelength end of G160M.
(SJH//LES)
e3t1323gz.r2h ECH-B 29 Mar 94 24 Apr 90 INFLIGHT Post-SV data from IDT.
(LES//SJH)
e751116az.r2h ECH-A 05 Jul 94 4 Feb 94 INFLIGHT Post-COSTAR data from IDT.
(CL/PL/SJH)
e751116cz.r2h ECH-B
e751116dz.r2h G160M
e751116ez.r2h G270M
e751116fz.r2h G140L
ebe1353oz.r2h G200M 18 Nov 94 4 Feb 94 INFLIGHT Post-COSTAR SSA vignetting from IDT for use with CALHRS v1.3.7.
(SJH/SJH/LES)
ebe1353pz.r2h ECH-A
ebe1353qz.r2h G140L
ebe1353rz.r2h G160M
ebe1353tz.r2h G270M
fc11607fz.r2h ECH-A 15 Dec 95 4 Feb 94 INFLIGHT Reordered groups to avoid IRAF bug which introduced errors into calibrated data for certain spectral orders. Deleted extra group for line_pos=139.712.
(LES//LES)

5.4 Absolute Sensitivity Files (ABSHFILE, NETHFILE).

The FLX_CORR switch controls the flux calibration on GHRS data. Each sensitivity file is associated with a net wavelength file, NETHFILE. The standard fluxes in the far ultraviolet were changed around the time COSTAR was installed and are now based on the star G191B2B, FOS high-resolution observations, and models by Finley. Note that time variable post-COSTAR sensitivities became available after GHRS was removed from HST during the Second Servicing Mission.

ABSHFILE GRATING NETHFILE DATE USE-AFTER PEDIGREE COMMENT
8cl1032iz.r3h ECH-A 8cl1122sz.r4h 20 Dec 89 24 Apr 90 GROUND Initial delivery from IDT. (These are missing from the file list attached to tracking form; would assume that these files were delivered at the same time as all the other initial deliveries and that the same persons (DL/ML/RLG) were involved)
8cl1035sz.r3h G140L 8cl11245z.r4h
8cl10342z.r3h G140M 8cl1123az.r4h
8cl1033dz.r3h ECH-B 8cl11234z.r4h
8cl1034jz.r3h G160M 8cl1123hz.r4h
8cl10353z.r3h G200M 8cl1123pz.r4h
8cl1035gz.r3h G270M 8cl1123tz.r4h
b9i1427bz.r3h ECH-A b9i14291z.r4h 11 Nov 91 24 Apr 90 INFLIGHT SV data from IDT. New grating names.
(DL//RLG)
b9i14285z.r3h G140L b9i14301z.r4h
b9i1427jz.r3h G140M b9i1429cz.r4h
b9i1427fz.r3h ECH-B b9i14297z.r4h
b9i1427nz.r3h G160M b9i1429hz.r4h
b9i1427rz.r3h G200M b9i1429lz.r4h
b9i14281z.r3h G270M b9i1429qz.r4h
e4e13583z.r3h ECH-B 14 Apr 94 04 Feb 94 INFLIGHT Interim post-COSTAR sensitivities for Side 2.
(SJH//)
e4e13582z.r3h G270M
e4e13581z.r3h G200M
e4e13580z.r3h G160M
e5v0936nz.r3h ECH-A e5v09367z.r4h 31 May 94 04 Feb 94 INFLIGHT Post-COSTAR sensitivities for all gratings. NOTE: UV fluxes corrected for updated standard, G191B2B. Based on FOS high dispersion observations and Finley models*1.005 for G191B2B only.
(CL/PL/SJH)
e5v0936oz.r3h ECH-B e5v09368z.r4h
e5v0936qz.r3h G140M e5v09369z.r4h
e5v0936rz.r3h G160M e5v0936az.r4h
e5v0936sz.r3h G200M e5v0936bz.r4h
e5v0936tz.r3h G270M e5v0936cz.r4h
e5v09370z.r3h G140L e5v0936ez.r4h
h4s1130pz.r3h G140L h4s1130qz.r4h 29 Apr 97 04 Feb 94 INFLIGHT New, Improved G140L baseline post-COSTAR sensitivity calibration. See GHRS-ISR-085.
(LES//LES)
h4s1135ez.r3h G140L h4s1130qz.r4h 29 Apr 97 14 Jun 94 INFLIGHT New time-variable G140L post-COSTAR sensitivities. Wavelength coverage is incomplete in these files.
(LES//LES)
h4s1135fz.r3h 01 Aug 94
h4s1135gz.r3h 21 Oct 94
h4s1135hz.r3h 14 Jan 95
h4s1135iz.r3h 17 Apr 95
h4s1135jz.r3h 25 Jun 95
h4s1135kz.r3h 17 Sep 95
h4s1135lz.r3h 04 Jan 96
h4s1135mz.r3h 02 Feb 96
h4s1135nz.r3h 30 Aug 96
h4s1135oz.r3h 22 Nov 96
h4s1135pz.r3h 24 Jan 97
h5m10094z.r3h G140L h4s1130qz.r4h 22 May 97 14 Jun 94 INFLIGHT Time-variable G140L post-COSTAR sensitivities. Same as above except wavelength coverage is now complete in these files.
(LES//LES)
h5m10095z.r3h 01 Aug 94
h5m10096z.r3h 21 Oct 94
h5m10097z.r3h 14 Jan 95
h5m10098z.r3h 17 Apr 95
h5m10099z.r3h 25 Jun 95
h5m1009az.r3h 17 Sep 95
h5m1009bz.r3h 04 Jan 96
h5m1009cz.r3h 02 Feb 96
h5m1009dz.r3h 30 Aug 96
h5m1009ez.r3h 22 Nov 96
h5m1009fz.r3h 24 Jan 97
h851622iz.r3h Ech-A e5v09367z.r4h 05 Aug 97 05 Aug 97 INFLIGHT Previous post-COSTAR Ech-A sensitivity corrected linearly (19% at all wavelengths) to agree with newer mu_col_006.tab reference file. See GHRS-ISR-088.
(JRM//LES)
h851622jz.r3h G140M e5v09369z.r4h 05 Aug 97 05 Aug 97 INFLIGHT Previous post-COSTAR G140M sensitivity corrected linearly (~2% at 1100A to ~8% at 1600A) to agree with newer mu_col_006.tab reference file. See GHRS-ISR-088.
(JRM//LES)
h9a11401z.r3h Ech-A e5v09367z.r4h 05 Aug 97 04 Feb 94 INFLIGHT Same as above Ech-A but with correct USEAFTER date.
(JRM//LES)
h9a11402z.r3h G140M e5v09369z.r4h 05 Aug 97 04 Feb 94 INFLIGHT Same as above G140M but with correct USEAFTER date.
(JRM//LES)
h9p15195z.r3h Ech-B e5v09368z.r4h 25 Sep 97 04 Feb 94 INFLIGHT Previous post-COSTAR Ech-B sensitivity corrected to agree with newer mu_col_006.tab reference file. See GHRS-ISR-090. Using this file, fluxes will no longer be overpredicted by ~35% at 1800A nor underpredicted by ~10% at 2800A.
(JRM//LES)

5.5 Data Quality Initialization (DQIHFILE).

This file is used to flag dead diodes in the GHRS Digicons during data quality initialization (DQI_CORR). The dead diodes are "removed" from the calibrated data during the merging of substep bins (controlled by the MER_CORR switch).

FILE DET DATE USE_AFTER PEDIGREE COMMENT
96t0916rz.r5h 1 20 Dec 89 24 Apr 90 GROUND Initial delivery from IDT.
(DL/ML/RLG)
96t09174z.r5h 2
c5516031z.r5h 2 07 Mar 92 24 Apr 90 INFLIGHT Set flag value of dead diodes to '400' to match calibration software.
(SJH/MEW/MEW)
c7u0854mz.r5h 1 31 Jul 92 24 Apr 90 INFLIGHT Set flag value of dead diodes to `400' to match calibration software.
(SJH/MEW/MEW)
cce1505kz.r5h 2 15 Dec 92 21 Dec 92 INFLIGHT Science diode 342 (348/512) turned of as of 92356.
(SJH/MEW/MEW)
f511531iz.r5h 2 12 Apr 95 15 May 95 INFLIGHT Science diode 237 (243/512) turned off as of 95135.
(LES/AG)
f5o1134qz.r5h 1 22 May 95 29 May 95 INFLIGHT Science diode 085 (091/512) turned off as of 95149.
(AG/LES)
g2e08383z.r5h 2 26 Feb 96 26 Feb 96 INFLIGHT Science diode 051 (057/512) turned off as of 96057.
(LES/DRS)

5.6 SAA Contour Mask Header (SAAHFILE)

This file is used by the optional background model correction switch (BMD_CORR), made available with calhrs v.1.3.11 (Mar 97), as a basis for the shape of the South Atlantic Anomaly (SAA) based on HST PDB (Project Database) Model 7. The location of HST during the observation is compared to the location of the SAA Model contour. Warning messages are issued for any readout which is found to encroach upon the SAA. Background count rate model results are unreliable in this region.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
h5m1337dz.r6h 22 May 97 24 Apr 90 MODEL SAA Contour Model 7 from PDB for Model BKGD (BMD_CORR) correction. See GHRS-ISR-084. Requires CALHRS v.1.3.11 or later.
(MdlP//LES)

5.7 Line and Sample Mapping Parameters (CCR1, CCR2).

The mapping parameter tables referred to in the MAP_CORR calibration step contain coefficients that relate the photocathode coordinate system to the diode array coordinate system. Sample position is measured in the dispersion direction while line position is measured perpendicular to the dispersion.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d10459z.cz1 06 Mar 90 24 Apr 90 GROUND Initial delivery from IDT.
(DL//RLG)
aau13518z.cz1 06 Nov 90 24 Apr 90 INFLIGHT OV data from IDT.
(LF//RLG)
FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045az.cz2 14 Mar 90 24 Apr 90 GROUND Initial delivery from IDT.
(DL//RLG)
aaj11108z.cz2 19 Oct 90 24 Apr 90 INFLIGHT OV data from IDT.
(RLG//RLG)
ba412190z.cz2 11 Nov 91 24 Apr 90 INFLIGHT Improved data from IDT; new grating names.
(DL//RLG)

5.8 Detector Parameters (CCR3).

Among many other things, this table determines how the background measurements are smoothed before being applied to the observations. The most recent version, dated 15 July 1992, forces the background to be calculated as a single average value across the spectrum, in order to avoid effects that were caused by using polynomials or straight lines. Many calibration steps use some subset of parameters from this table.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045bz.cz3 06 Mar 90 24 Apr 90 GROUND Initial delivery from IDT.
(DL//RLG)
bc41634lz.cz3 04 Dec 91 24 Apr 90 INFLIGHT Values for polynomial background smoothing added.
(DL//RLG)
c7f1130oz.cz3 15 Jul 92 24 Apr 90 INFLIGHT Order for polynomial smoothing of background set to zero.
(SJH/MEW/MEW)

5.9 Wavelength Ranges (CCR4).

The wavelength range table contains the valid ranges of wavelength that are applicable to each grating of the GHRS. This reference table is, in fact, not now used by the calibration software.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045dz.cz4 06 Mar 90 24 Apr 90 GROUND Initial delivery from IDT. NOTE: This reference table is currently not used by the calibration software.
(DL//RLG)

5.10 Spectrum Constants (CCR5).

In the process of the wavelength calibration, the application of dispersion constants (controlled by switch ADC_CORR) step makes use of this table to determine which spectrum order was observed, especially when echelle-mode observations are obtained.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045fz.cz5 06 Mar 90 24 Apr 90 GROUND Initial delivery from IDT.
(DL//RLG)
bc41510sz.cz5 04 Dec 91 24 Apr 90 GROUND New grating names.
(MEW//MEW)
e3u1415mz.cz5 30 Mar 94 24 Apr 90 INFLIGHT Modified to support global dispersion coefficient algorithm. Added values for all first order gratings.
(LES//SJH)
e3u1417oz.cz5 30 Mar 94 16 Jan 94 INFLIGHT Global dispersion coefficient algorithm constants modified to use Post-Servicing Mission Side 1 Carrousel positions (which are based on Side 2 encoder values).
(LES//SJH)

5.11 Dispersion Constants (CCR6).

The determination of a wavelength solution (controlled by the ADC_CORR switch) uses these dispersion constant values to generate wavelength scales appropriate to the mode of observation This table is indexed by carrousel position-interpolation in this table is often necessary. This table is used when the global wavelength solution is not used, i.e. calibration step GWC_CORR is set to OMIT.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045hz.cz6 06 Mar 90 24 Apr 90 GROUND Initial delivery from IDT.
(DL//RLG)
aau1352az.cz6 30 Oct 90 24 Apr 90 INFLIGHT OV data from IDT. WARNING: this table contains incorrect values for the dispersion coefficients at certain carrousel positions.
(LF//RLG)
ba412199z.cz6 04 Nov 91 24 Apr 90 INFLIGHT New grating names. Same errors as previous table.
(DL//RLG)
c3v1133gz.cz6 31 Mar 92 24 Apr 90 INFLIGHT NOTE: Errors in previous two tables have been corrected.
(SJH/SJH/SJH)
e3t1251bz.cz6 29 Mar 94 16 Jan 94 INFLIGHT Side 1 values modified for Post-Servicing Mission Side 1 Carrousel positions (which are based on Side 2 encoder values).
(LES//SJH)

5.12 Thermal Constants (CCR7).

Thermal constants are used during the wavelength solution calibration step (ADC_CORR) to correct the wavelength scales for the effect of temperature within the GHRS.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045iz.cz7 06 Mar 90 24 Apr 90 DUMMY Initial delivery from IDT.
(DL//RLG)
ba41219bz.cz7 04 Nov 91 24 Apr 90 INFLIGHT SV data from IDT; new grating names.
(DL//RLG)
e3t1250tz.cz7 29 Mar 94 24 Apr 90 INFLIGHT Table modified and columns added for improved global dispersion coefficient determination. Data provided by IDT.
(LES//SJH)

5.13 Incident Angle Correction, or Aperture Offsets (CCR8).

All GHRS wavelengths are referenced to the SSA. Light enters the LSA and the two spectral calibration lamp apertures at different angles than for the SSA; a zero-point shift in wavelength is seen. The IAC_CORR step places non-SSA observations on the same wavelength scale as the SSA.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045jz.cz8 06 Mar 90 24 Apr 90 DUMMY Initial delivery from IDT.
(DL//RLG)
aau1352fz.cz8 30 Oct 90 24 Apr 90 INFLIGHT OV data from IDT.
(LF//RLG)
ba41219ez.cz8 04 Oct 91 24 Apr 90 INFLIGHT SV data from IDT; new grating names.
(DL//RLG)
bb110387z.cz8 01 Nov 91 24 Apr 90 INFLIGHT SV data from IDT for LSA/ G160M, G200M, G270M combinations. NOTE: Some DUMMY data for Side 2 gratings still included.
(DL//RLG)
e3t1250lz.cz8 29 Mar 94 16 Jan 94 INFLIGHT Side 1 values modified for Post-Servicing Mission Side 1 Carrousel positions (which are based on Side 2 encoder values). NOTE: DUMMY values in previous table removed.
(LES//SJH)
h2615285z.cz8 18 Feb 97 04 Feb 94 INFLIGHT New LSA offsets measured in program 6213. No change to G140L. See GHRS-ISR-080.
(ABS//LES)

5.14 Echelle Blaze Function Interpolation and Non-Interpolation (CCR9 and CCRA).

The ECH_CORR calibration step uses the constants contained in these tables to correct echelle observations for the effect of the echelle blaze function as part of the spectrum rectification process.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045kz.cz9 06 Mar 90 24 Apr 90 DUMMY Initial delivery from IDT.
(DL//RLG)
bb11038hz.cz9 01 Nov 91 24 Apr 90 INFLIGHT SV data from IDT; new grating names.
(DL//RLG)
e3t1250az.cz9 29 Mar 94 16 Jan 94 INFLIGHT Side 1 values modified for Post-Servicing Mission Side 1 Carrousel positions (which are based on Side 2 encoder values).
(LES//SJH)
e751042hz.cz9 05 Jul 94 4 Feb 94 INFLIGHT Post-COSTAR data from IDT. Data may be incorrect for both gratings.
(CL/PL/SJH)
e8c09237z.cz9 12 Aug 94 4 Feb 94 INFLIGHT Increased carrousel position range to prevent incorrect interpolation.
(SJH//SJH)


FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1045mz.cza 06 Mar 90 24 Apr 90 GROUND Initial delivery from IDT.
(DL//RLG)
bb11038kz.cza 01 Nov 91 24 Apr 90 INFLIGHT SV data from IDT; new grating names.
(DL//RLG)
e3t1249fz.cza 29 Mar 94 16 Jan 94 INFLIGHT Side 1 values modified for Post-Servicing Mission Side 1 Carrousel positions (which are based on Side 2 encoder values).
(LES//SJH)
e5n1103iz.cza 23 May 94 16 Jan 94 INFLIGHT Added "CPNORM" column to provide carrousel position for normalization of ripple function. Corresponding change made to CALHRS. Table is for post-Side 1 turn on data.
(SJH//SJH)
e5n1355kz.cza 23 May 94 04 Apr 90 INFLIGHT Added "CPNORM" column to provide carrousel position for normalization of ripple function. Corresponding change made to CALHRS. Table is for pre-COSTAR data.
(SJH//SJH)
e751041qz.cza 05 Jul 94 04 Feb 94 INFLIGHT Post-COSTAR IDT values.
(CL/PL/SJH)
e8c0922rz.cza 12 Aug 94 04 Feb 94 INFLIGHT Corrects values for ECH-A "CPNORM" column.
(SJH//SJH)

5.15 Scale Factors for Scattered Light Subt raction (CCRB).

The background subtraction step in calibration determines the degree of scattered light in the spectrum. Currently only the data for the echelle gratings are non-dummy, inflight values. Scattered light contamination in the 1st order gratings is relatively unimportant.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
bbf1357dz.czb 15 Nov 91 24 Apr 90 DUMMY DUMMY installed by STScI. New gratings names. NOTE: This table is missing values for some orders.
(SJH//RLG)
bc41437gz.czb 04 Dec 91 24 Apr 90 DUMMY Data for missing orders added.
(SJH//RLG)
d8b1457az.czb 13 Aug 93 24 Apr 90 INFLIGHT New scattered light coefficients for Echelle gratings taken from Cardelli, Ebbets, and Savage, ApJ 413, p.401,1993.
(SJH//LES)
ga20907fz.czb 01 Oct 96 24 Apr 90 INFLIGHT Same as above. Resubmitted to correct CDBS error which triplicated some lines.
(AMG//AMG)

5.16 Global Wavelength Coefficients (CCRC).

The global wavelength coefficients table is used by the wavelength solution calibration step (ADC_CORR) to determine wavelength coefficients when GWC_CORR is set to PERFORM. This table differs from table CCR6 in that it is not indexed on carrousel position. Instead, the coefficients to a global solution across all carrousel positions is contained in table CCRC. This is the preferred method for producing a wavelength scale.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
e3u1428cz.czc 30 Mar 94 24 Apr 90 INFLIGHT Values for global dispersion coefficient algorithm to determine wavelengths. Also includes zero point temperatures of all GHRS thermal monitors on which Global Coefficients are based. Data provided by IDT.
(LES//SJH)
e3u14301z.czc 30 Mar 94 16 Jan 94 INFLIGHT Side 1 values for global dispersion coefficient determination modified for Post-Servicing Mission Side 1 Carrousel positions (which are based on Side 2 encoder values).
(LES//SJH)

5.17 Photocathode Blemish Locations (CCRD).

The photocathode blemish location table contains locations of known photocathode blemishes and is used by calhrs to update data quality flags and to mark regions and severity of blemishes. The table was delivered 29 March 1994 but may be applied to any observations since launch.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
e3t1028nz.czd 29 Mar 94 24 Apr 90 INFLIGHT Locations of known photocathode blemishes. Data provided by IDT and used by CALHRS v.1.3.4 to update data quality flags to mark region and severity of blemish.
(LES//SJH)

5.18 Background Count Rate Model (CCRE).

The background count rate model is used with the optional background model correction switch (BMD_CORR), available in calhrs v.1.3.11 (Mar 97). When set to PERFORM, the BMD_CORR switch will calculate and subtract a model background based on location of the telescope's orbit instead of using the background bins obtained with an observation. The SAA Model 7 contour is used to issue warning messages per readout of an observation (see SAAHFILE). Results from the background count rate model are not reliable in or near the SAA. This table contains mean derived background count rates as a function of geomagnetic latitude and longitude. The model is actually the blue FOS model derived by Rosenblatt, et. al (1992) multiplied by a GHRS-detector-specific scaling factor. Header keywords in the table contain the multiplicative scaling factors required to scale the results from the model to the appropriate GHRS detector.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
h5m13378z.cze 23 May 97 24 Apr 90 INFLIGHT Rosenblatt, et al.'s FOS Blue background count rate model (based on geomagnetic latitude and longitude) multiplied by a scale factor appropriate to the GHRS detector. See GHRS-ISR-084. Requires CALHRS v.1.3.11 or later.
(MdlP//LES)

5.19 Paired-Pulse Corrections (CCG2).

Correction for detector dead-time requires information contained in table CCG2. This table is actually shared with FOS, although the data used are unique to GHRS.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
a3d1145ly.cmg 15 Dec 89 24 Apr 90 GROUND Initial delivery from IDT. This table is "shared" with FOS.
(//)

6.Tables stored in CDBS but not used by CALHRS

6.1 Platinum-Neon Lamp Line List.

The Platinum-Neon line list table contains laboratory measurements of wavelengths for features of a Platinum-Neon spectrum calibration lamp. These are uniformly transformed to vacuum wavelengths at all wavelengths and this information is used during post-pipeline processing by the wavecal task.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
d9r16547z.czy 15 Sep 93 24 Apr 90 GROUND This table contains laboratory wavelengths for the Pt-Ne spectral calibration lamps taken from Reader, et al. Ap.J.Suppl. 72, 1990, p. 831 corrected to vacuum wavelengths. Used by wavecal task.
(JDE//SJH)

6.2 Small Science Aperture Wavelength Offsets.

The SSA wavelength offset table contains wavelength offsets between the SSA and SC1 and SC2. This table is used during post-pipeline processing by the wavecal task.

FILENAME DATE USE_AFTER PEDIGREE COMMENT
d9f14083z.czz 15 Sep 93 24 Apr 90 GROUND This table contains offsets between the SSA and SC1 and SC2. Used by zwavecal task.
(JDE//SJH)

May not have been updated for all post-COSTAR Side 1 Carrousel positions.

h9m1538dz.czz 25 Sep 97 16 Jan 94 GROUND Updated for all post-COSTAR Side 1 Carrousel positions. (MdLP//LES)