title constant temper black body limit from Ferland and Rees 1988
c tests whether departure coef are forced to unity by induced processes
c
c commands controlling continuum =========
black body, t = 50000 lte
c
c commands for density & abundances =========
hden 10
init file="hheonly.ini"
c
c commands controlling geometry  =========
stop lyman continuum optical depth -6
set dr -10
stop zone 1
c
c other commands for details     =========
iterate 
constant temper 50000
c
c commands controlling output    =========
print populations h-like
print heating
print departure coef
print line faint -1
save overview "limit_h_induc.ovr"
save performance "limit_h_induc.per"
save monitors "limit_h_induc.asr" last
c
c commands giving the monitors    =========
monitor h-like departure coef hydrogen, average 1
monitor h-like departure coef helium, average 1
c limit_h_induc.in
c class limit 
c ========================================
c 

This example tests whether induced processes force level populations
of hydrogen to LTE when they are irradiated by a
blackbody in strict thermodynamic equilibrium.  The density is
low enough value for radiation to dominate the rate equations
coupling levels with each other and the continuum.  The expectation
is for all departure coefficients to equal unity.

Checks:
-	Departure coefficients exactly unity.
-	Grain temperatures are exactly 5*104 K.