Gm. Hill et Jd. Landstreet, COMPOSITIONAL DIFFERENCES AMONG THE A-TYPE STARS .1. 6 NARROW-LINED STARS, Astronomy and astrophysics, 276(1), 1993, pp. 142-160
We have determined abundances of up to 18 chemical elements using spec
trum synthesis for half a dozen narrow-lined A-type stars. Except for
Sirius (a hot Am star) and perhaps o Peg all are classified as normal.
Our results agree fairly well with those in the literature obtained u
sing more traditional techniques. Considerable star-to-star abundance
variations are present, even among the apparently normal stars. The ab
undance of iron varies over a range of about 0.7 dex and the abundance
s of most elements seem to vary at least roughly with those of iron. O
ur results are consistent with an approximately constant helium undera
bundance with respect to the Sun for all six stars; carbon exhibits an
anti-correlation with iron.