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restrepo
GitHub Repository: restrepo/ComputationalMethods
Path: blob/master/data/plasma/ABOUT.dat
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ABOUT THE COOLING FUNCTIONS

The associated files contain the cooling functions calculated for the paper
by R. S. Sutherland and M. A. Dopita to appear in ApJS in 1993.  See paper
or preprint for details.

*****FILE LIST

1) Collisonal Ionisation Equilibrium cooling functions as a function
of metallicity are given in the files:

	mzero.cie   : cie cooling for primordial hydrogen/helium mix log(T) = 4-8.5
	m-00.cie    : cie cooling for solar abundances mix log(T) = 4-8.5
	m-05.cie    : [Fe/H] = -0.5, solar/primordial average ratios
	m-10.cie    : [Fe/H] = -1.0, primordial ratios (ie enhanced oxygen)
	m-15.cie    : [Fe/H] = -1.5, primordial ratios
	m-20.cie    : [Fe/H] = -2.0, primordial ratios
	m-30.cie    : [Fe/H] = -3.0, primordial ratios
	m+05.cie    : [Fe/H] = +0.5, solar ratios log(T) = 4.1-8.5 (due to charge 
                   exchange problems at log(T) = 4.0)

2) Non-Equilibrium (NEQ) cooling functions as a function
of initial temperature are given in the files:

a) full internal diffuse field transfer (ie plane parallel case)
	pk6ff55.neq   : NEQ cooling for solar mix log(T0) = 5.5 down to 4.0
	pk6ff65.neq   : NEQ cooling for solar mix log(T0) = 6.5 down to 4.0
	pk6ff75.neq   : NEQ cooling for solar mix log(T0) = 7.5 down to 4.0
	pk6ff85.neq   : NEQ cooling for solar mix log(T0) = 8.5 down to 4.0
a) Zero internal diffuse field transfer (ie limiting case for fragmenting condensations)
	pk6zf55.neq   : NEQ cooling for solar mix log(T0) = 5.5 down to 4.0
	pk6zf65.neq   : NEQ cooling for solar mix log(T0) = 6.5 down to 4.0
	pk6zf75.neq   : NEQ cooling for solar mix log(T0) = 7.5 down to 4.0
	pk6zf85.neq   : NEQ cooling for solar mix log(T0) = 8.5 down to 4.0

3) Non-Equilibrium (NEQ) cooling functions as a function
of metallicity are given in the files:

pressure domain of models log(p/k) = 6

a) full internal diffuse field transfer (ie plane parallel case)
	pk6ff75m-05.neq   : NEQ [Fe/H] = -0.5; log(T0) = 7.5 down to 4.0
	pk6ff75m-10.neq   : NEQ [Fe/H] = -1.0; log(T0) = 7.5 down to 4.0
	pk6ff75m-15.neq   : NEQ [Fe/H] = -1.5; log(T0) = 7.5 down to 4.0
	pk6ff75m-20.neq   : NEQ [Fe/H] = -2.0; log(T0) = 7.5 down to 4.0
	pk6ff75m-30.neq   : NEQ [Fe/H] = -3.0; log(T0) = 7.5 down to 4.0
a) Zero internal diffuse field transfer (ie limiting case for fragmenting condensations)
	pk6zf75m-05.neq   : NEQ [Fe/H] = -0.5; log(T0) = 7.5 down to 4.0
	pk6zf75m-10.neq   : NEQ [Fe/H] = -1.0; log(T0) = 7.5 down to 4.0
	pk6zf75m-15.neq   : NEQ [Fe/H] = -1.5; log(T0) = 7.5 down to 4.0
	pk6zf75m-20.neq   : NEQ [Fe/H] = -2.0; log(T0) = 7.5 down to 4.0
	pk6zf75m-30.neq   : NEQ [Fe/H] = -3.0; log(T0) = 7.5 down to 4.0


*****FILE FORMAT

The data files consist of tab separated ASCII column data described as follows:

log(T): log temperature in K

ne	nH	nt : number densities, electrons, hydrogen and total ion in cm^-3.

log(lambda net)	log(lambda norm) : log on the net cooling function
and the normalised cooling function.  lambda norm = lambda net / (ne nt).
lambda net in ergs cm^-3 s^-1,  lambda net in ergs cm^3 s^-1.  While the 
densities are kept less than about p/k 10^8 both isobaric and isochoric
curves can be constructed from the normalised function using an appropriate
density function.  The non-equilibrium net cooling function is from the 
isobaric model used to calculate the curves.  In the CIE curves the net function
is for the isochoric cie model.

log(U):  U = 3/2 N kT   , N = ne + nt the total internal energy. ergs cm^-3

log(taucool):  The normalized cooling timescale Nr*( U/(lambda net))
               Nr = (ne nt)/(ne+nt).   s cm^-3

P12:  Gas pressure NkT. ergs ergs cm^-3 times 10^12

rho24:  Density g  cm^-3 times 10^24

Ci: The isothermal sound speed kms s^-1

mubar: mean molecular weight grams times 10^24

*****NOTES

Tests showed that density quenching begins to affect the curves in the low 
temperature parts of the cooling functions when log(p/k) = 8 or more.

Above log(T) = 7.5-8.5 it should be pretty safe to use a powerlaw
fit to the free-free losses

Good luck, and let me know if you have any problems.

These files will be available via anonymous ftp from 

merlin.anu.edu.au

login:anonymous
password:<your email address>

they will reside in the /pub/cool.

If you do not have ftp access, email arrangements can be made.

Yours sincerely

Ralph S. Sutherland  1992-1993.

-- Ralph S. Sutherland      Mount Stromlo & Siding Spring Observatories.
-- [email protected]  The Australian National University.
-- [email protected] --------------------------------------------