     DESCRIPTION OF THE OPACITY TABLES: tableD2_NaH2_T_1e21_FS17.omg

They have been done for the D2 lines from T=500 to 3000K with a step size
of 500 K for an H2 density = 1e21 cm-3.

The "FS17" is an annotation that these tables were computed  using the
ab initio  potentials of Fernand Spiegelman 2017 for the
Na-H2 sytem (see Allard et al 2019).



They are valid up to a H2 density = 1e21 cm-3. They use the density expansion
described in Section 3.3 of Allard et al 2019



In the header I summarize the physical parameters:
TK: 1000.00
lambda: 5891.58
absorption oscillator strength fabs     0.64 cgs
 r0 and fabs and pi*r0*fabs      0.28000E-12    0.64080E+00    0.56368E-12
 see Eq.15  of Allard et al 2019
 radiator perturber mass:   23.00    2.00
 perturber density [cm-3]  0.10000E+22
omega cm-1 1st order.. until      15order
the first column of the table is \Delta omega cm-1 and following are the
15 terms of the density expansion Eq.14 of Allard et al 2019.
end
 5891.582  1.E+21  7.60885796               5.6367712E-13
 lambda    density      vn                  pi*r0*fabs

vn = 7.60885796 is a normalization factor for the  wing

 91                              15
number of points of the table    n_exp the order of the expansion

w_impact= 21.9821136  d_impact=1.69550044  in cm-1  are the line parameters
of the Lorentzian core (see Eq.14 of  Allard et al 2019)

 -3800.  1.57986974E-08  1.02353996E-07  3.80553396E-07  9.58880637E-07
  1.80693018E-06  2.70901701E-06  3.36802587E-06  3.57567608E-06
  3.31245589E-06  2.72220794E-06  2.01048642E-06  1.34837985E-06
  8.28244917E-07  4.69271889E-07  2.46724919E-07

\Delta \omega_min=-3800 cm-1



last point of the table is \Delta \omega_max=+4100 cm-1

the sampling  for $\Delta \omega$ is not constant it is very small close to the
core to make easier the junction between the near wing and the core of the
line given by a Lorentzian,  the line parameters are the impact
width and shift.

for each \Delta \omega I give  the 15  expansion  coefficients.

DESCRIPTION OF lect_sig.f

 lect_sig.f will read the table and will make the sum of the different terms of
the expansion until n_exp (see Eq.14 of  Allard et al 2019)

n_exp, the order of the expansion varies according to the temperature.

 the output are:
 
sigma_out.omg and sigma_out.lam for the wings,

lorentz_out.omg and  lorentz_out.lam for the core of  D1 or D2.

The input to read and process lect_sig.f is in lect_sig.csh

#run lect_prof
lect_sig<<%
densout
1.e21
domegc         sampling for the core 
0.5
nsf             number of points computed for the core 
1000
tableD2_NaH2_1000_1e21_FS17.omg


the different terms of the density expansion  reported in  the table
are computed for a density  dens_in =10^21,
for a density dens_out the first term of the expansion
will be multiplied by vn1=dens_out/dens_in, the second term by vn1**2 etc...

 the sampling for the wing is not constant, 100cm-1 in the far wing 
but  a smaller one in the near wing 10cm-1


 -10.  0.0678282956  0.40490037  1.09441101  1.95410855  2.67586719  3.01409084
  2.90439174  2.45471742  1.8516123  1.26274172  0.786435761  0.45093421
  0.23964576  0.118708486  0.0550739704
  0.  0.621223182  1.29471944  2.23689115  3.19191961  3.84883623  4.00662026
  3.66451081  2.98672931  2.19447725  1.4674465  0.900237113  0.510101036
  0.268524455  0.131985893  0.0608416396
  10.  0.0748869111  0.44747949  1.20985222  2.16076618  2.95950996  3.33424833
  3.21346752  2.71636159  2.04923885  1.39765886  0.870523044  0.499166478
  0.265277718  0.131399605  0.0609567064

For the junction between the Lorentzian core and the near wing the sampling
domegc for the Lorentzian and nsf the number of points computed for the core
have to be chosen as nsf x domegc to be larger than 3x10 cm-1, 10  cm-1 being
the sampling in the core.

when dens_out  gets very small domegc decreases and nsf increases to
to provide the Lorentzian core accurately. The files will be large.
Be carefull of the dimension in the lect_sig.f program.

