SIMBAD references

Nitrogen and sulphur abundances in 15 sharp-lined `normal' main sequence A stars are determined from new high-resolution CCD spectra. Non-LTE effects are taken into account. Nitrogen abundances are distributed over an interval of 0.5dex around the solar value of 8.05. Non-LTE abundance corrections range from -0.2 to -1.2dex. Sulphur is overabundant with respect to the sun by 0.1 to 0.6dex in all program stars. Taking non-LTE effects into account reduces the overabundances, but cannot remove them entirely; non-LTE abundance corrections {DELTA}logε are typically -0.1dex. Comparison with previously derived carbon abundances reveals that carbon and nitrogen behave very similarly in each star. Thus the anticorrelation of [C/Si] with [Si/H] found by Holweger (1992, Lecture Notes in Physics Vol. 401, eds. U. Heber and C.S. Jeffery, p. 48) is also true for [N/Si]. For sulphur a similar anticorrelation is also possible.