Chemically Peculiar stars

A star which shows spectral abnormalities with respect to other stars in its spectral type is classified as chemically peculiar. Six classes of such stars are known, and they tend to lie on the instability strip on the Hertzsprung-Russell diagram. Whether this curious coincidence has a physical reason remains an open question. In this work, I reviewed the classification of these stars using spectral data from the SOPHIE and ELODIE archive.