Details of the Galactic OB models

The main parameters of this grid are the stellar temperature T and the surface gravity ggrav. The spacing of the stellar temperatures is 1 kK, while it is 0.2 dex for the surface gravity. The luminosities are derived from the stellar evolution models published by Ekström et al. (2012). The terminal wind velocity v is derived from the escape velocity. The models are calculated for log [M/(M/yr)] values of -7.0. A clumping of D=10 is assumed. Wind clumping starts at the sonic point and increases outwards until a stellar radius of R = 10 R.

The Galactic abundances are adopted from the TMAP abundance list.

Summary of the model atoms:

IonNo. of levels
H I 22
H II 1
He I 35
He II 26
He III 1
N I 10
N II 38
N III 85
N IV 38
N V 20
N VI 14
C I 15
C II 32
C III 40
C IV 25
C V 29
C VI 1
IonNo. of levels
O I 13
O II 37
O III 33
O IV 29
O V 36
O VI 16
O VII 15
S III 23
S IV 11
S V 10
S VI 1
Mg I 1
Mg II 32
Mg III 43
Mg IV 17
Mg V 20
Si I 20
IonNo. of levels
Si II 20
Si III 24
Si IV 23
Si V 1
P IV 12
P V 11
P VI 1
G I 1
G II 3
G III 13
G IV 18
G V 22
G VI 29
G VII 19
G IX 15
G X 1

Notes: Element "G" stands for the generic iron-group element, which combines the elements from Sc to Ni in solar relative mixture. In case of the "G" element, the number of levels given in the above table actually refers to superlevels.

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