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tamode stsdas.hst_calib.hrs.z_calib



tamode -- Analyze GHRS target acquisition field map.


tamode input aperture table tabstat


This routine will analyze the results of an GHRS target acquisition field map. It will create an output table, or append to an existing table. the following information about the map image:

o The left and right edge positions, computed as the position where the flux is 1/2 the maximum flux in the X-profile of the image (computed by summing all image lines).

o The upper and lower edge positions in the Y-profile (computed by summing all samples in each line).

o The X-center (the midpoint between the left and right edges).

o The Y-center (the midpoint between the upper and lower edges).

o The X- and Y-centroid of the image.

o The X and Y centers (computed by cross-correlation of the X and Y profiles with templates of user-specified widths).

o The area of the image computed as:


o The total flux in the image.

Optionally, the program will add the positions of the spectral calibration lamp apertures (computed by the GHRS on-board software) to the output table.

The X and Y coordinate system is in deflection units, giving the position viewed by the upper left focus diode.


input [file name]
The name of the input image containing the GHRS field map.
aperture = "lsa" [string, allowed values: lsa | ssa | sc| sc2]
Name of the aperture that was used to observe in the map.
table = "tamode" [file name]
The name of the output table to be written or appended. This table will have the following columns:

     'APERTURE'   - Aperture name (char*3).
     'LEFT_EDGE'  - Location of the left edge (double).
     'RIGHT_EDGE' - Location of right edge (double).
     'UPPER_EDGE' - Upper edge location (double).
     'LOWER_EDGE' - Lower edge location (double).
     'X_CENTER'   - Center computed from edges (or on-board
		    deflection calibration of SC1 and SC2) (double).
     'Y_CENTER'   - Center computed from edges or the on-board
		    deflection calibration (double).
     'X_CENTROID' - Centroid in the X-direction (double).
     'Y_CENTROID' - Centroid in the Y-direction (double).
     'X_CROSSCOR' - Center in X from cross-correlation (double).
     'Y_CROSSCOR' - Center in Y from cross-correlation (double).
     'AREA'       - Area of aperture computed from edge positions.
     'FLUX'       - Total flux in the image.
     'TIME'       - Spacecraft packet time for the map (char*24).
tabstat = "write" [string, allowed values: write | append]
Method used to store output data. Specifying "write" will cause a new table to be created. If "append" is specified, then the results will be written to the end of the present output table; in this case, the input map must be for the same acquisition mirror mode as the table's current data.
(twidthx = 5) [integer, min=1, max=21]
Cross correlation template width for the X-direction (must be an odd value). Even values passed to twidthx will be incremented.
(twidthy = 5) [integer, min=1, max=21]
Cross correlation template width for the Y-direction (must be an odd value). Even values passed to twidthy will be incremented.
(map = yes) [boolean]
Process the field map and put the results in the output table?
(defcal = yes) [boolean]
Put the results of the deflection calibration performed by the onboard software into the output table? The location of both spectral calibration lamps will be added to the table.


1. Compute the aperture parameters for the small science aperture using the image mapssa. Also include the SC1 and SC2 locations from the on-board deflection calibration.

hr> tamode mapssa "SSA" "write"

2. Append results for the large aperture to the previously created table. Do not include the deflection calibration results.

hr> tamode maplsa "LSA" "append" defcal=no




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