Abstract
ABSTRACT With the results of previous atmospheric diagnoses (Allen 1977) and equivalent-width data derived mostly from plates from the Dominion Astrophysical Observatory, abundances have been computed from lines of singly ionized chromium, manganese, and iron in a sample of A- and B-type normal and metal-enriched stars. The pertinent Warner (1967) oscillator strength scales were adjusted in accordance with recent laboratory work and measurements from the solar spectrum. The stars in the sample, which includes normal, Hg-Mn, Ap, and Am stars, show a wide variation in the relative abundances of these elements; in two very pronounced Mn stars, 53 Tau and HR 2844, large manganese excesses (i.e., Mn/Fe greater than 1) are derived. This result indicates the operation of nonnuclear processes on the composition of the observable layers of these stars.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
