Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-12T20:42:52.718Z Has data issue: false hasContentIssue false

The Nature of the Chemical Anomalies of the Sirius A

Published online by Cambridge University Press:  14 August 2015

V. Leushin*
Affiliation:
Special Astrophysical Observatory of RAS, Russia [email protected]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

On the basis of the analysis of the observed equivalent line widths of FeI, FeII, and TiII in the spectra of Sirius A and Omicron Peg and calculation of abundances of these elements, the oscillator strengths of the lines used are refined. With the improved oscillator strengths, the iron and titanium abundances in the atmosphere of Sirius A are obtained with a higher accuracy than previously:

lgN(FeI) = 7.899 ±0.011,

lgN(FeII) = 7.908±0.010,

lgN(TiII) =5.30±0.02.

The improved accuracy allowed one to conclude that the surface magnetic field is absent in the atmosphere of Sirius A: H =3D 0±100 Gs. The equivalent widths of 7 helium lines of the red region of the spectrum are measured. The calculations of these lines (with allowance for their blending with lines of other elements) show normal helium abundance. Following a comparison of features of Sirius A and Omicron Peg, a suggestion is advanced on possible reasons for the existence of Am stars.

Type
II. Joint Discussions
Copyright
Copyright © Kluwer 1998