Antenna List
Standard Telescopes
Many are delivered with CASA. You need to find your data repository, whose location can vary with installation and operating system.
CASA <10> repodir=os.getenv("CASAPATH").split(' ')[0]+"/data/alma/simmos/"
If you look there you will see ALMA, CARMA, EVLA, etc, and can set the antennalist input to one of them
CASA <11> ls repodir
CASA <11> antennalist=repodir+"almaconfig.out20.cfg"
ALMA
You need to pick a configuration number based on desired resolution. This plot will help:
File:Beamsummary.png 300 pix
You can also use this python program: [1] to suggest a beam configuration for you, but you will need to download this table of beams [2] and unpack the tarball in your working directory.
Others, including your own, possibly fictitious Observatory
the configuration files are merely ASCII files with four or five columns: X,Y,Z,diameter, and optional station name. For example for ALMA, the columns are
- UTM-X (Easting; meters).
- UTM-Y (Northing; meters).
- Z (Altitude in meters)
- Diameter (meters). =simdata= uses a primary beam calculated using Airy patterns for the diameters you specify and a 1m diameter circular blockage in the center of each antenna or station. CASA has more accurate primary beams for some observatories, and will used those if available.
The file must begin with header information defining the columns. such header lines begin with "#", and must include at least the observatory name and coordinate system:
- observatory = VLA
- coordsys = XYZ
Some coordinate systems require further definitions to uniquely specify them.