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

118 APPENDIX D. BAT SOFTWARE TOOL REFERENCE
(aperture) [filename ]
Aperture file. The default is the aperture file in the CALDB area. This parameter may
be omitted or set to “NONE” if only background cleaning is required (i.e., the srcclean
parameter set to “NO”). If several aperture types are available in the CALDB, the user can
specify CALDB:apertype. Valid values of apertype are currently: FLUX or DETECTION,
for apertures optimized for flux reproducibility or detection sensitivity, respectively.
(detmask) = “NONE” [filename ]
Name of a detector mask file. This should be an image file with the same dimensions as the
focal plane map. A pixel value of 0 indicates the detector is enabled for imaging, and a value
of 1 indicates disabled, noisy, or otherwise selected for elimination from fits. A default value
of NONE implies all detectors are on, except for the BAT detector gap regions.
• It is strongly recommended to use a detector mask file if one is available. The quality of the
fit, especially to calibration data is greatly improved if only working detectors are included
in the fits.
(wtmapin) = “NONE” [filename ]
Name of an input error map. This is used to provide weights for the fitting in case one is
cleaning a DPI which does not have Poisson statistics (such as an already cleaned DPI). The
typical sequence would be to create an error map using the wtmapout parameter on the first
cleaning and then read this error map in on the second cleaning. If an already cleaned image
is cleaned without an input error map than uniform weighting is used.
(wtmapout) = “NONE” [filename ]
Name of an output error map. If a filename is specified then the tool writes out a DPI
containing the calculated weights for each detector. This can be used on subsequent cleanings
as the input wtmapin error map.
(backexp) = “NONE” [filename ]
If the name of a file is given here, then the background model will be output to this file. The
format is a binary table with one column for each model parameter. The data is written in
DPH format, or as a 286 X 173 element array, one number per detector. This table gives the
model which was fit to the data, not the actual fit to the data. The final column in the table
is the covariance matrix from the fit.
(bat z) = 0 [real ]
This is the z-component of the distance to the source in BAT Z coordinates (the vertical
distance of the source from the origin of the BAT coordinate system). This parameter is
ignored if srcclean = “NO.” If the incatalog contains a BAT Z keyword, then the value of the
keyword is used and the value of the bat z parameter is not used. Note that the default value
of 0 corresponds to a source at infinity.
(bkgmodel) = “simple” [string ]
This optional parameter indicates the background model to be fit. Currently only two models
are hard coded: the simple model which is the 14 parameter fit described above and an even
simpler test model which was used in testing the fit procedures. As more sophisticated
background models are developed, they will be incorporated into the code.