Imaging simulations

To use $\cal OYST\!ER\,$for imaging simulations, first create a data set using the fakedata procedure. This will create scans, for which one can compute model values using calcmodel after reading a model file. calcmodel will compute the complex visibilities (scans.complexvis) and squared visibilities (scans.vissqm). If one wants to write this data into a FITS file, nothing needs to be copied since the procedure put_fits uses the complex visibilities to derive the FITS visibility variables amplitude and phase. If noise is to be added to the visibilities, it should be added to the real and imaginary parts of scans.complexvis.

The data can then be mapped in AIPS with or without using phase self-calibration.