Analysis of C II resonance lines in some main sequence early-type stars

IUE data are used to investigate C II resonance lines at 1335 A in eight main-sequence stars of spectral types from A0 to B3, and both LTE and non-LTE line profiles have been computed. In stars with low rotational velocities (such as Vega, Pi Cet, and Tau Her), logarithmic carbon abundances log N(C/H) of -3.55 to -3.45 are obtained for the non-LTE case. The LTE analysis reveals lower carbon abundances by about 0.1 dex. Significant differences among the fast rotating stars are pointed out.