Define model gas density, . This is actually the hydrogen nucleus
density, so that, e.g., the total particle density in a fully-ionized
plasma with solar abundances is
.
Units are cm
. The default value is
1 cm
. Whether or not this quantity is held fixed is determined
by the value of the constant pressure switch lcpres.
If the density is constant then the appropriate definition
of ionization parameter (
) is adopted.
The constant density case is the default.
Note: see the section for the radexp parameter for additional density input options.