CALSTIS Version 2.19 was released on 2005-November-03 in the new STSDAS release, Version 3.3.1, which can be found on the STSDAS Download Page.

Update: This version of CALSTIS was installed in the OTFR pipeline on 2006-April-10

The following OPRs are implemented in the release of CALSTIS 2.19:

OPR 52667:	Correct for temperature-dependent sensitivity in CALSTIS
OPR 53524:	CALSTIS6 should apply grating/aperture flux correction (gactab)
OPR 53707:	CALSTIS CTE correction is not correct for subarrays
OPR 53708:	CALSTIS fails when virtual overscan is all zero
OPR 53210:	Include xpos parameter in x1d.cl for calstis6
OPR 53709:	CALSTIS4 can overwrite memory for long-slit data

OPR 52667: Correct for temperature-dependent sensitivity in CALSTIS

The flux correction in 'calstis7' now also includes a dependence on the temperature. Temperature corrections have been implemented by adding two columns to the TDS file. One called REFTEMP contains a single value for each optical element. The second column, TEMPSENS, uses the same wavelength grid as already defined by the TDS corrections so that the temperature correction can be allowed to vary as a function of wavelength for an individual grating (although initially we will use a constant value for each grating).

The correction factor to the extracted flux at each wavelength will then be

(1  +  TEMPSENS  *   (temp-REFTEMP))

Where temp is given by the science extension header keywords:
OM1CAT for the FUV-MAMA
OM2CAT for the NUV-MAMA
OCCDHTAV for side-2 CCD data

The TEMPSENS, and REFTEMP columns have the following values:

Modes	TEMPSENS	REFTEMP
FUV-MAMA	-.00265+/-.00035	36.0
NUV-MAMA	+0.0	36.0
G230LB/MB	+.00337+/-.0002	19.0
G430L/M	+.0021+/-.00045	19.0
G750L/M	+0.0	19.0

For side 1 CCD data the correction factor will always be unity (no temperature correction). However, the TDS reference files will always contain just the side 2 values, so applying no temperature correction for side-1 CCD data has been hard wired into the code based on detector==CCD and the observation date.

The temperature correction factor will be calculated at each wavelength for which the TDS vector is defined, and then linearly interpolated to each wavelength in the data. The correction then gets applied at the same time that the TDS correction gets applied.

OPR 53524: CALSTIS6 should apply grating/aperture flux correction (gactab)

For some STIS modes, the grating and aperture throughputs cannot be simply multiplied together to get the net throughput for point sources. Instead, an additional wavelength-dependent correction factor that depends on the grating/aperture combination used was needed. A new reference table (GACTAB) has been created to contain the array of correction factors for various combinations of grating, central wavelength, and aperture. Calstis6 has been modified to read this table, unless the name is blank or "N/A", and apply the correction factor during the flux-correction step.

OPR 53707: CALSTIS CTE correction is not correct for subarrays

The correction for the nonuniformity of charge transfer efficiency in CALSTIS did not allow for the possibility of a subarray. The algorithm for CTE correction for a subarray is not known for sure. The simplest solution was to assume that the loss of CTE is the same as if the data were in a full-frame exposure at the location of the subarray. This simple adjustment has been implemented within CALSTIS6 to the function responsible for flux correction.

OPR 53708: CALSTIS fails when virtual overscan is all zero

A bug in the blevcorr step was found in the code that rejected outliers in the virtual overscan region. When all values of the virtual overscan were zero, CALSTIS rejected all those values and tried to divide by the number of valid points, which was then zero. This was fixed by regarding all the pixels as valid if they're all zero.

OPR 53709: CALSTIS4 can overwrite memory for long-slit data

Due to the use of the F1 aperture for a wavecal observation, one of the occulting bars was about 100 pixels off the aperture. There was a loop in CALSTIS with incorrectly specified loop limits so that they depended on the location of the occulting bar, and CALSTIS wrote beyond the end of an array, which resulted in a bus error.

OPR 53210: Include xpos parameter in x1d.cl for calstis6
(Related OPR 53714: Change CALSTIS6 command-line flag -st to be an offset)

The 'xoffset' parameter from calstis6 made visible in the 'x1d' task. This xpos parameter allows one to specify the X pixel location of an undispersed image. This is necessary in order to correct for an offset in the dispersion direction or to extract the spectrum of a target that is not the one used for target acquisition.

CNSHD542457: ODELAYTIME: hstephem needs to be consistent with current version of odelaytime
CNSHD542451: ODELAYTIME: extraneous factor of pi/180

Relativistic correction in 'odelaytime' was corrected to use the proper units for the velocity aberration angles.