*Astronomy 206. Stellar Physics
STELLAR ATMOSPHERE
(From "Astrophysics Simulations", by Danby, J.M.A., Kouzes, R.,
& Whitney, C., Wiley, 1995.)
The program ATMOS allows you to calculate a model of the atmosphere
of a star by specifying the stellar mass, radius and luminosity. You
can derive these parameters by first using STELLAR, ZAMS, EVOL, or
another stellar interior program. ATMOS assumes that the gas is
stratified in homogeneous shells concentric with the center of the star.
The shells are thin, and hence may be represented by plane parallel
layers. ATMOS uses the Boltzmann-Saha law to calculate the ionization
of the gas, and the source function equals the Planck function - LTE.
Convection is treated with mixing length theory.
You can run ATMOS on the 486 PC in the computer room (A 111). Switch on
the computer (on your left side) and the monitor. Wait for it to reboot;
it will be in C: drive when done. If already on, go to C: drive. Go to
subdirectory CUPS/CUPSAS (use chdir). Here all computer codes reside. Go
to subdirectory ATMOS and type ATMOS. Under menu item [File] you can
read about the code and how to use it.