Search Publications

Formation of resonance spectral line profiles in stellar wind: Theory and observations

Sapar, L.; Sapar, A.

The theory of the formation of resonance spectral line profiles in the stellar wind of hot stars has been elaborated taking into account the presence of microturbulent motions. In this case the local frequency redistribution in the line profile function is incomplete. This circumstance generates dominating backscattering of photons and drastic cha…

New Insights on Late-A and Early-F Star Activity

Talavera, A.; Freire Ferrero, R.; Bruhweiler, F. +3 more

The onset of chromospheric activity in late-A and early-F stars is here discussed. The detection of Ly- emission core in several A and F atars with the IUE satellite, gives evidence for the presence of chromospheric layers in these stars up to B - V = 0m.19 (Marilli et al., 1996). Semiempirical chromospheric models for Altair allowed us (Freire Fe…