Grid of 3D helium-rich LTE synthetic spectra

Separate files for log (g) = 7.5, 8.0, 8.5, 9.0
Each file has a variable temperature range.
Composition (y = He/H in number) is for pure-He (y=1e30), 1e7, 1e5, 1e4, 1e3 and 1e2

Each model atmosphere was spatially and temporally averaged before calculating
the mean 3D spectra.

File format:

 1) Grid of 2610 wavelength points in Angstrom
 2) For each model at fixed gravity
    Header
    "Effective temperature =   [value]  gravity =  [value]  y =  0.000E+00"
    Grid of 2610 Fnu Eddington fluxes in air wavelength 
    (units of erg cm^-2 s^-1 Hz^-1)

Main reference
Cukanovaite, E., Tremblay, P.-E., Bergeron, P., et al. (2021) MNRAS, 501, 5274.

Conversion:

The flux at Earth is f = 4*pi*R^2/D^2 * Eddington flux

where R is the white dwarf radius, D the distance and the Eddington flux 
the quantity in the files. The radius can be found from Evolutionary Sequences.
There are several sources including the website below
https://www.astro.umontreal.ca/~bergeron/CoolingModels/

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Physics included in the calculations:

3D hydrodynamics convection
Freytag, B. et al. 2012, JCoPh, 231, 919
Cukanovaite, E., Tremblay, P.-E., Bergeron, P., et al. (2021) MNRAS, 501, 5274.

Non-ideal effects from charged and neutral particles 
Hummer, D.G. and Mihalas, D. 1988, ApJ, 331, 794
(Bohr radii of H I, H2, He II and He III have a free parameter of 0.5;
see Tremblay et al. 2010, ApJ, 712, 1345; Cukanovaite et al. 2021 MNRAS, 501, 5274)

Lyman, Balmer, Paschen, Brackett lines profiles (extended to a total of 60 lines in 2015)
Tremblay, P.-E. & Bergeron, P. (2009) ApJ, 696, 1755

Hydrogen neutral broadening profiles for Lyman alpha, beta, gamma and delta
Allard, N. 2014, public website (https://www.iap.fr/useriap/allard/lymantables.html)
Broadening due to charged particles for these lines is treated from the Tremblay+2009 reference above.

Hydrogen neutral broadening profiles for Lyman alpha from H2-H and H-H collisions
Kowalski, P. M., Saumon D. 2006, ApJ, 651, L137
(Warning: H-He collisions are not included)

H2 collision-induced absorption (including high-density corrections from Hare & Welsh 1958)
H2-H2 from Borysow et al. (2001, JQSRT, 68, 235)
H2-H from Hitran database (http://hitran.org/cia/)
H2-He from Jorgensen et al. (2000, A&A, 361, 283)
H-He from Gustafsson et al. (2001, APJ, 546, 1168)

H minus bf and ff opacity
John, T. L. 1988, A&A, 193, 189

He I bf, He II bf, He II ff, He III ff, He minus
Beauchamp A., 1995, PhD thesis

He I Stark broadening
Beauchamp A., 1995, PhD thesis (Stark broadening)

He I neutral broadening
Unsöld (1955) Physik der Sternatmospharen
Cukanovaite, E., Tremblay, P.-E., Bergeron, P., et al. (2021) MNRAS, 501, 5274.

He2+ bf and ff opacity
Stancil 1994, JQSRT, 51, 655

H2 minus ff opacity
H2+ bf and ff opacity
H bf opacity (>972 Angstrom Hummer & Mihalas pseudo-continuum cut)
H, H2 and H3 ff opacity
Stimulated emission
H, H2, He I, He II Rayleigh scattering
(Standard references, e.g. Mihalas 1978 Stellar Atmospheres book and Kurucz 1970, Atlas: A Computer Program)