The photospheric barium spectrum: Solar abundance and collision broadening of Baii lines by hydrogen |
| |
| Authors: | Hartmut Holweger Edith A Müller |
| |
| Institution: | (1) Institut für Theoretische Physik und Sternwarte der Universität Kiel, Kiel, F.R.G.;(2) Observatoire de Genève, Sauverny, Switzerland |
| |
| Abstract: | A study of the solar Ba ii spectrum leads to a solar abundance of barium of log
ba = = 2.11±0.12, on the scale log
h = 12. The observed asymmetry of the resonance line  4554 is consistent with an isotopic abundance ratio equal to the terrestrial one. The meteoritic Ba/Si abundance ratio found in carbonaceous chondrites appears to exceed the solar ratio by 0.1 to 0.2 dex (Section 5).The broadening by collisions with hydrogen atoms is determined from the solar spectrum (Section 4). Damping half-widths, 
h, of the three stronger Ba ii lines turn out to be larger by a factor of about 3.0 than predicted from pure van der Waals interaction of dipoles.
Departures from LTE appear to be present in the cores of the resonance lines and of the lines arising from the metastable 5D levels (Section 6). The equivalent widths, however, remain practically unaffected.Equivalent widths of neutral barium lines are predicted and some new identifications of photospheric Ba i lines are suggested (Section 7). |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
