APIE TFAISeminaro vadovas: habil. dr. Gražina TAUTVAIŠIENĖ
Seminaro sekretorius: Eduardas PUZERAS
Tematika: astrofizika, astronominiai prietaisai ir stebėjimų metodika, mokslo organizaciniai klausimai
Detalesnė informacija: tel. 2193250, el. paštas Grazina.Tautvaisiene@tfai.vu.lt
Lyudmila Mashonkina (Institute of Astronomy, RAS, Russia) pranešimas
Gerbiami kolegos,
Š. m.sausio 16 dieną (trečiadienį), 11:00 Goštauto 12 ketvirtojo aukšto salėje pranešimą
skaitys užsienio svečias.
Pranešėja: Lyudmila Mashonkina, Institute of Astronomy, RAS, Russia
Pranešimo tema: Determination of stellar parameters and chemical abundances
based on non-LTE line formation
(Cheminės sudėties ir pagrindinių žvaigždžių parametrų nustatymas pagal NLTE linijas)
Anotacija:
The talk will concern with two type stars. Stars with effective temperatures close to the solar one and with various metallicities give important information for the studies of the Galaxy chemical evolution. Departures from LTE may significantly affect determinations of stellar parameters and chemical abundances of such stars, in particular, metal-poor stars. I will review the application of the non-LTE ionization equilibrium between Fe I and Fe II and between Ca I and Ca II to constrain the surface gravity of very metal-poor and hyper metal-poor stars spectroscopically. An astrophysical problem will be reviewed where non-LTE line formation for the selected atoms is considered in chemically stratified atmosphere and this leads to better interpretation of observed data. This is a violation of the ionization equilibrium between the second and first ions of rare-earth elements in rapidly oscillating chemically peculiar stars. What is meant by non-LTE will be briefly described in the introduction.
Kviečiame dalyvauti!
Eduardas
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