Details of the WNL-H50 models (2016 version)

Note: This model grid, put online on 17.10.2016, replaces the previous version which, for reference, is still accessible by choosing "WNL-H50-2013" in the drop-down menu. The major improvement of the 2016 version concerns the iron-group elements. The superlevels are now grouped by states of the same parity. This avoids the spurious emission from Fe III that had been present in the UV spectra of the cooler models in the previous version. Moreover, ionisation stages of iron (and iron-group elements) up to Fe XVII are now taken into account for the hotter part of the grid.

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 1 0
N II 38 1
N III 85
N IV 38
N V 20
N VI 1
IonNo. of levels
C II 3
C III 40
C IV 25
C V 1
G II 1 0
G III 13 1
G IV 18
G V 22
G VI 29
G VII 19
IonNo. of levels
G IX 15
G X 1 28
G XI 0 26
G XII 0 13
G XIII 0 15
G XIV 0 14
G XV 0 10
G XVI 0 9
G XVII 0 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.

If two entries are given for the same ion, the first one refers to the cooler and the second entry to the hotter part (T* of 79 kK and higher).

Contour plots

For a couple of lines, contour plots of the equivalent width have been prepared. The contours are labeled with Wλ in Angstroem:

Hα ps pdf png
Hβ ps pdf png
He I5876 ps pdf png
He II5412 ps pdf png
C IV5801-5812 ps pdf png
N III4640 ps pdf png
N IV4058 ps pdf png
N V4604-4620 ps pdf png
N V4933-4944 ps pdf png

The following contour plot relates the stellar temperature T, which refers to the hydrostatic radius, to the "effective" temperature T2/3 referring to the radius of the optical depth 2/3. The contours are labeled with log T2/3 in Kelvin.

ps pdf png
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