1.1.1. table star CoStar, temp=34,700K log(g)=4  [index 2, ZAMS, age]

The CoStar (Schaerer et al. 1996a, b; and Schaerer & de Koter 1997) grid of windy hot stellar atmospheres was incorporated into Cloudy in collaboration with Peter van Hoof.  These stars have temperatures ranging from 18,521K through 53,397K.  The original ASCII file obtained from their web site must be compiled to bring it into the Cloudy energy mesh and convert to binary format for rapid access.  There are many possible ways to interpolate on this grid, as described next.

table star CoStar, 37,000K, index 2. The CoStar grid consists of 6 evolutionary tracks, each corresponding to a specific Zero Age Main Sequence (ZAMS) mass.  Each track consists of several models (ranging from 3 to 7, depending on the track). The index number of the model corresponds to a specific age of the star as it is followed through its evolution. So the index number is a rough way to indicate how evolved the star is; index 1 indicates a main sequence star, higher numbers indicate more evolved stars. A summary of the effective temperatures of all models can be found in Table 11. The index is the second optional number on the command line if the keyword index appears.

If only one number is on the line and no keyword appears, an index of unity is assumed.  It is possible to specify a ZAMS mass, surface gravity, or age with the following commands.  The original CoStar file should be consulted to see what range of parameters is available.

table star Costar, 37,000 4.  With no keyword the second parameter is the log of the surface gravity.

table star CoStar, ZAMS mass=30, time=1000000.  With the ZAMS keyword the ZAMS mass and age of the star is specified.

table star CoStar, age=1000000, mass=30.  With the _AGE keyword the mass and age of the star is specified.

Last changed 03/31/03.
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