NAME

det2att2 - Converts detector coordinate offsets and rotations to attitude quaternions

USAGE

det2att2 infile outfile teldeffile startsys

DESCRIPTION

The det2att2 task calculates the spacecraft rotation quaternions corresponding to offsets in detector coordinates. The det2att2 task can also incorporate time-dependent rotations of the detector coordinate system relative to the SKY coordinate system. This option requires that the input file has columns for the sine and cosine of the rotation angle; otherwise the rotation angle is assumed to be zero.

The det2att2 task is mission-independent and allows the selection of the origin system of the transformation using the parameter 'startsys'. The quaternion qdelta for an offset (dx, dy) is such that with a mapping of a detector position p = (px, py) to SKY coordinates using an attitude q0, yield identical results when applying qdelta*q0 to p as applying q0 to (p-dx, p-dy).

PARAMETERS

infile = offsets.fits [filename]
Name of input offset file.

outfile = deltaq.fits [string]
Name of output attitude file.

(teldeffile = teldef.fits) [string CALDB|file name]
Name of the teldef file. If the parameter is set to CALDB, the file is read from the calibration database.

startsys = SKY_FROM [string]
Name of the starting coordinate system. This must be either one of the coordinate systems defined in the file specified by the 'teldeffile' parameter, or the special value SKY_FROM. For teldef file format versions older than 0.2 and 'startsys=SKY_FROM', the originating coordinate system is read from the SKY_FROM keyword in 'teldeffile'.

(deltaxcol = DELTADETX) [string]
Column name for the offset in the detector X-coordinate.

(deltaycol = DELTADETY) [string]
Column name for the offset in the detector Y-coordinate.

(sincol = SINANGLE) [string]
Column name for the sine of the rotation angle of the detector coordinates.

(coscol = COSANGLE) [string]
Column name for the cosine of the rotation angle of the detector coordinates.

(clobber = no) [boolean yes|no]
Overwrites the existing output file if set to yes.

(chatter = 1) [integer 0|1|2|3]
Chatter level for output. Set to 0 to suppress output, or to 1, 2, or 3 for increasing the chatter of the output.

(logfile = !DEFAULT) [string DEFAULT|NONE|file name]
Log file name. If set to DEFAULT, uses the name of the task and, if preceded by "!", overwrites the file if it exists. If set to NONE, no log file is created.

(debug = no) [boolean yes|no]
Diagnostic output is printed out on the screen if set to yes.

(history = yes) [boolean yes|no]
Records tool parameters in HISTORY.

EXAMPLES

  1. Convert an offset file derived from Hitomi CAMS into a delta-attitude quaternion. The input file is the output of cams2det. The teldef file is that for HXI1, which is the instrument for which the offsets were derived.
    2.    det2att2 infile=CAMS_offsets.fits outfile=delta_attitude.att teldeffile=ah_hxi1.teldef startsys=RAW
      deltaxcol=DELTARAWX deltaycol=DELTARAWY clobber=yes
  2. Convert an offset file derived from Swift TAM into a delta-attitude quaternion. The teldef file is that for Swift/XRT. The 'deltaxcol' and 'deltaycol' parameters can be the default values. The 'sincol' and 'coscol' parameters are ignored. 
    3.    det2att2 infile=TAM_offsets.fits outfile=delta_attitude.att teldeffile=sw_xrt.teldef startsys=SKY_FROM clobber=yes

SEE ALSO

det2att, cams2det, cams2att

LAST MODIFIED

February 5, 2024