Table 1
Opacity of Rayleigh scattering at τRoss ≈ 1 for a model atmosphere with Teff = 23 000K together with its comparison with the opacities of the Balmer continuum and electron scattering.
| Solar chemical composition | Helium-rich stars |
|
|
|
| nHe ii ≈ 104nH i | nHe ii ≈ 106nH i |
| σHe ii ≈ 10-3σH i | |
| χHe ii ≈ 10χH i | χHe ii ≈ 103χH i |
|
|
|
| nHe ii ≈ 10-1ne | nHe ii ≈ ne |
| σHe ii ≈ 10-3σe | |
| χHe ii ≈ 10-4χe | χHe ii ≈ 10-3χe |
|
|
|
| nHe ii ≈ 105nH i2 | nHe ii ≈ 106nH i2 |
| σHe ii ≈ 10-9σH i2 | |
| χHe ii ≈ 10-4χH i2 | χHe ii ≈ 10-2χH i2 |
|
|
|
|
|
Notes. The cross section is calculated for frequency 2.4 × 1015 s-1 where the flux is largest (according to Wien’s displacement law). In this table n stands for particle number density, σ for the Rayleigh scattering cross section, and χ for the opacity. Lower subscripts He ii and H i of cross section and opacity stand for Rayleigh scattering and e for free electrons. χH i2 is the Balmer continuum opacity and nH i2 number of hydrogen atoms with n = 2.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.