Nitrogen abundance in early B-stars I. NLTE calculations for gamma Pegasi

Based on Kurucz (1992) grid of models the NLTE calculations of nitrogen abu ndance in gamma Peg atmosphere revealed a slight deficiency of this element comparably to solar value ([N/H] approximate to -0.3). Together with the r ecent result on carbon abundance in this star atmosphere ([C/H] = -0.25; Ko rotin et al., 1998), the present determination shows that turbulent diffusi on in massive main sequence stars (discussed by Maeder, 1987) and connected with it the appearance of the CN-processed material at the stellar surface can hardly be operating in gamma Peg. The list of N II lines that can be used for LTE calculation of nitrogen abu ndance in hot stars is also presented.