BALTIC ASTRONOMY, cilt.14, sa.1, ss.51-82, 2005 (SCI-Expanded)
Elemental abundance analysis based on high S/N and high resolution Dominion Astrophysical Observatory spectrograms have been performed for two early type supergiants: 4 Lac (B9 lab) and v Cep (A2 Ia). Lines as weak as of order 5 mA are employed in this study. I The projected rotational velocities of these stars are 14 and 26 km s(-1) respectively. Both stars show similar radial velocity amplitudes, macro-turbulent velocities and the same general elemental abundance trends. Their He, CNO and light element abundances are solar or overabundant while the iron peak and heavy element abundances are solar or underabundant. Detailed LTE model atmosphere abundance analysis shows that 4 Lac has nuclearly processed matter in its photosphere while v Cep does not.