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inttag stis


NAME · USAGE · PARAMETERS · DESCRIPTION · EXAMPLES · BUGS · REFERENCES
SEE_ALSO

NAME

inttag -- Convert an events table of TIMETAG into an integrated ACCUM image.

USAGE

inttag input output

PARAMETERS

input [string]
Input file that contains TIMETAG event stream. This is ordinarily a FITS file containing two tables. The TIMETAG data are in the table with EXTNAME = "EVENTS", and the "good time intervals" are in the table with EXTNAME = "GTI". If the GTI table is missing or empty, all times will be considered "good".
output [string]
Name of output FITS file.
(starttime = INDEF) [real]
Start time for integrating events, in units of seconds since the beginning of the exposure. The default value of INDEF means that the start time will be set to the first START time in the GTI table.
(increment = INDEF) [real]
Time interval in seconds. The default value of INDEF means integrate to the last STOP time in the GTI table.
(rcount = 1) [int, min = 1, max = INDEF]
Repeat count, the number of output image sets to create. If rcount is greater than 1 then increment must also be specified (but starttime may still be set to INDEF).
(highres = no) [bool]
Create a high resolution output image?
(allevents = no) [bool]
If allevents is set to yes, all events in the input EVENTS table will be accumulated into the output image. The TIME column in the EVENTS table will only be used to determine the exposure time, and the GTI table will be ignored.
(verbose = yes) [bool]
Print additional info?

DESCRIPTION

The task inttag converts an events table of TIMETAG mode STIS data into a raw, time-integrated ACCUM image. inttag integrates the TIMETAG event stream in time to produce an ACCUM mode image integrating over only the good time intervals. The output image can be calibrated as any other raw image.

INPUT AND OUTPUT FILES

The input file for inttag is an event stream table of TIMETAG mode produced by generic conversion. The data will be Doppler corrected (as required for medium and high resolution spectroscopic modes). This file will consist of a primary header with no data, and two binary table extensions. The primary header is identical in structure to the primary header of an ACCUM mode image. The first binary table (EXTNAME=EVENTS) contains a list of the events themselves (i.e. science data as an event stream), and the second binary table (EXTNAME=GTI) contains a list of good time intervals for the TIMETAG exposure. Columns "TIME", "AXIS1", and "AXIS2" in the EVENTS table are read. Columns "START" and "STOP" in the GTI table are read.

The output image is a time integrated (ACCUM mode) image with the same structure as any other STIS MAMA raw image (i.e. primary header followed by a single or series of triplet extensions: SCI, ERR, DQ). The number of triplets is determined by the value of rcount. The time interval in the Nth triplet covers from (starttime + (N-1)*increment) to (starttime + N*increment). The exposure time in each interval need not be identical, because events are included in the image only if they occur during "good time intervals" (as determined by the GTI extension table). The keyword OBSMODE in the primary header of the output image will still be set to "TIME-TAG".

The output science image is ready to be calibrated (see calstis, crreject, basic2d, x2d, x1d).

EXAMPLES

1. To process an inttag file in the data set with rootname "o3xv04nfm". The output image will be in low resolution:

      cl> inttag o3xv04nfm_tag.fits o3xv04nfm_raw.fits

2. As above, but create a five-imset output file, starting at 27.3 seconds after the shutter opened, with each imset integrated over 100 seconds.

      cl> inttag o3xv04nfm_tag.fits o3xv04nfm_raw.fits starttime=27.3 \
	  increment=100 rcount=5

3. As above, but let the start time default to the first good time interval in the GTI table.

      cl> inttag o3xv04nfm_tag.fits o3xv04nfm_raw.fits starttime=INDEF \
	  increment=100 rcount=5

BUGS

REFERENCES

STIS ISR 96-13, S. Baum et al, July 1996.
Iraf task written by R. Katsanis.
INTTAG routine written by N. Zarate.

SEE ALSO


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