The elemental opacities are calculated on a uniform grid of
temperatures, electron degeneracy paramaters and dimensionless photon
energies u, where u is defined as:
u = hv / kT
hv is the photon energy in eV and kT is the temperature
in eV. The u grid is selected instead of the photon energy grid
because the same u grid can be used for all temperatures and
cover the important photon energy ranges needed to integrate the
Rosseland and Planck "gray" opacities. These photon energy ranges
would be 0. - 20. eV for a temperature of 1. eV and 0. - 2000. eV for
a 100. eV temperature. For the u grid, the range would be 0. -
20. for both temperatures.
u Grid used on the Web Page
The opacities are calculated on a grid of 14,900 u points
for each temperature point. This grid is shown below:
u Values 14,900 Point Grid
_________ ___________________________
0.0
|
| 9600 points, steps of .00125
|
12.5
|
| 1600 points, steps of .005
|
20.0
|
| 1000 points, steps of .01
|
30.0
|
| 700 points, steps of .1
|
100.0
|
| 900 points, steps of 1.0
|
1000.0
|
| 900 points, steps of 10.0
|
10000.0
|
| 200 points, steps of 100.0
|
30000.0
_____
14900 points