The SWIFT BAT Software Guide Version 6.3 30 ... - HEASARC - Nasa

D.14. BATMASKWTEVT 163
(distance = 1.0e7) [real ]
Default bat z position if bat z is zero (centimeters).
(maskoffx = 0.0) [real ]
Translational offset to apply to the mask along the BAT X coordinate from its nominal design
position.
(maskoffy = 0.0) [real ]
Translational offset to apply to the mask along the BAT Y coordinate from its nominal design
position.
(maskoffz = 0.0) [real ]
Translational offset to apply to the mask along the BAT Z coordinate from its nominal design
position.
(maskthickness = INDEF) [string ]
Thickness of the lead mask tiles in centimeters. Normally this will be set to INDEF, which
reads the mask thickness from the aperture file. A thickness of 0 cm is permitted.
(distfile=CALDB) [string ]
The ‘distfile’ parameter should point to a FITS file containing an MxNx2 image (or CALDB
to use the default instrument correction in the calibration database). The two planes of the
image are the non-linear distortion of the BAT “plate scale” as a function of position in the
sky image. The values are offsets in tangent plane coordinates (IMX,IMY), and therefore
unitless. The first plane of the image cube is the IMX offset, and the second plane is the
IMY offset. The sense of the offset is (TRUE-APPARENT), i.e. for a measured position in
tangent plane coordinates, the offset values should be *added* to arrive at the true position
in tangent plane coordinates. The images are low-resolution versions of the BAT field of view
in instrumental sky coordinates, and are meant to be interpolated to the desired sampling.
The WCS keywords must specify the image coordinate systems.
(buffersize = 32768) [integer ]
Size of internal event buffer for processing.
(subpixsize = 0.02) [real ]
Size of detector subpixels used in computing mask weighting, in centimeters. Can be no larger
than 0.02 cm.
(teldef = “CALDB”) [string ]
BAT instrument telescope description file, which defines instrument-to-spacecraft alignments.
Must be specified when celestial coordinates are provided. If the CALDB database is set up,
then CALDB can also be specified.
(origin z = 0) [real ]
For ground testing with a near-field source. The position of the origin of coordinates (in cm),
to which the source position is referred.
(maskwtswgain = 0.04) [real ]
Mask weight technique software gain correction factor. When corrections=maskwt, the
weights are divided by (1+maskwtswgain). This is correction is software algorithm dependent
and not intended to be changed by the user.