The Source Model File

The model.dat file contains the source model parameters required by uvplot to generate SNR curves and to compute model visibilities for output in FITS files. Each of the components are arranged horizontally by rows with a `#' signalling the start of a comment. The order of the data are as follows:

• 1. X position from phase center in milliarcseconds.
• 2. Y position from phase center in milliarcseconds.
• 3. The component flux in millijanskys.
• 4. The FWHM along the major axis in milliarcseconds.
• 5. The FWHM along the minor axis in milliarcseconds.
• 6. The position angle of the major axis measured from north toward east.
• 7. The percentage polarization of the component.
• 8. The position angle of the polarization vector measured from north toward east.

Model.dat can be directly modified from within uvplot by selecting the model option(see figure on p. ). If this file is modified or edited outside the program, the user must make sure that the format of the lines is unchanged. If any entries are not properly placed, uvplot will abort due to an error in reading the file. It is thus safest to modify model.dat from within uvplot, so the file format is automatically preserved.