Advantages and Limitations of the Astrophysical Web Page

Depending on the user's needs, this Web Page should be considered an
alternative to the main Web Page.  While there are several advantages to
this page, there are also limitations.  Both will be summarized below.
 

Users must always remember that neither these precalculated opacity tables
or data from the main Opacity Web Page contain any molecular species in
the equation of state or any molecular cross sections in the opacity
calculations.  Users must provide their own tables below 12,000 oK
if they wish to include these important molecular contributions.
 
Users also need to remember that all of the equation of state calculations
are done in local thermodynamic equilibrium (LTE).
 

 
ADVANTAGES
 
  1. Rosseland opacity tables may be obtained for a large number of
     complex mixtures in a fraction of the time and effort it would
     take to calculate the same data on the main web page.
 
  2. The tables are given in terms of oK and R, which are more
     standard parameters for astrophysical modeling than temperatures
     in keV and densities in gm/cc.  R input is not an option on the
     main web page at present, but may be added in the future.
 
LIMITATIONS
 
  1. Users can not create new mixtures.
 
  2. Thera are no Planck opacities, frequency dependent opacities or
     average ionization tables for the astrophysical mixtures.
 
  3. The R grid is fixed and can not be chosen by the user in the way
     that the density grid can be chosen on the main opacity web page.
     This means that the user can select a sub grid of the R's, but can
     not obtain a more detailed grid or points outside of the given R
     range.