title redshift 1000 recombination epoch
c
c commands controlling continuum =========
c a true blackbody radiation field, in strick thermo equilibrium
blackbody 3000 STE
c
c commands for density & abundances =========
hden 0
abundances primordial
c
c commands controlling geometry  =========
stop zone 1
c
c other commands for details     =========
case b 
iterate
c
c commands controlling output    =========
normalize lines to "Ca B" 4861
print ages
print departure coef
print line faint -5
save overview "igm_z3.ovr"
save performance "igm_z3.per"
save monitors "igm_z3.asr"
c
c commands giving the monitors    =========
// >>chng 01 sep 24, from 80.5 to 59.2, lower def case b optical depth
// >>chng 03 may 17, from 59.2 to 23.6, update pump more often
// >>chng 04 mar 04, from 23.6 to 54.07, improv conv
// >>chng 04 jun 12, from 54.07 to 80.0, chng cont shield fcn
// >>chng 07 oct 22, from 80.0 to 111.7, resolve l-levels of h-like sequence
// >>chng 12 oct 22, from 111.7 to 92.71, zone tau in rt_line_one
monitor line "H  1" 4861 92.71
//
monitor hydrogen 2 tempeature 3000
//
// >>chng 00 mar 22, widflx, pump bug from -0.709 to -0.672, also error
// >>chng 01 aug 23, from 0.672 to 0.699, 2x better con res
// >>chng 01 sep 24, from -0.699 to -1.06 lower def case b optical depth
// >>chng 03 may 17, from -1.06 to -1.26 update pump more often
// >>chng 04 mar 04, from -1.26 to -1.11 improv conv
// >>chng 04 jun 12, from -1.11 to -0.651 chng cont shield fcn
// >>chng 12 oct 22, from -0.651 to -0.9445, zone tau in rt_line_one
monitor ionization hydrogen 2 -0.9445 error 0.06
//
// >>chng 01 sep 24, from 0.304 to 0.326 lower def case b optical depth
// >>chng 02 may 27, from 0.326 to 0.359, improved brems gaunts
// >>chng 02 jun 21, from 0.359 to 0.320, improved brems gaunts
// >>chng 03 may 17, from 0.320 to 0.347 update pump more often
// >>chng 04 mar 04, from 0.347 to 0.327, imrov conv
// >>chng 04 jun 12, from 0.327 to 0.294 chng cont shield fcn
// >>chng 11 nov 16, from 0.294 to 0.3225, adjust newmole monitors
// >>chng 11 dec 16, from 0.3225 to 0.2677, adjust botches due to recent iso recomb changes
// >>chng 12 oct 22, from 0.2677 to 0.2963, zone tau in rt_line_one
monitor line "ff h" 0 0.2963
//
// >>chng 01 sep 24, from 0.0185 to 0.049 lower def case b optical depth
// >>chng 03 may 17, from 0.049 to 0.0806 update pump more often
// >>chng 04 mar 04, from 0.0806 to 0.0555, imrov conv
// >>chng 04 jun 12, from 0.0555 to 0.0162 chng cont shield fcn
// >>chng 12 oct 22, from 0.0162 to 0.0365, zone tau in rt_line_one
monitor line "h- h" 0 0.0365
//
// >>chng 01 sep 24, from 0.0163 to 0.043 lower def case b optical depth
// >>chng 03 may 17, from 0.043 to 0.0703 update pump more often
// >>chng 04 mar 04, from 0.0703 to 0.0485, imrov conv
// >>chng 04 jun 12, from 0.0485 to 0.0142 chng cont shield fcn
// >>chng 12 oct 22, from 0.0142 to 0.0321, zone tau in rt_line_one
monitor line "h-fb" 0 0.0321
//
// >>chng 01 sep 24, from 0.0103 to 0.027 lower def case b optical depth
// >>chng 03 may 17, from 0.027 to 0.0444 update pump more often
// >>chng 04 mar 04, from 0.0444 to 0.0307, imrov conv
// >>chng 04 jun 12, from 0.0307 to 0.0090 chng cont shield fcn
// >>chng 12 oct 22, from 0.009 to 0.0203, zone tau in rt_line_one
monitor line "h2+ " 0 0.0203
//
c igm_z3.in
c class limit igm
c ========================================
c 

This is a model of the universe near the recombination epoch, at
a redshift of a thousand.  The gas is exposed to a true blackbody at
3000 K, and the abundances are primordial.