Astrophysics (Index)About

chemically peculiar star

(CP star, peculiar star)
(star with SED showing presence metals unusual for stars)

A chemically peculiar star (CP star, often what is meant by peculiar star) is a star with an unusual SED, indicating the presence of metals not expected in such stars, particularly if it does not fit the sequence of spectral features used to identify spectral classes. The common types are thought to stem from conditions at star formation, but other types may result from interactions of binary stars. Four common patterns:

Other types:

There are some post-main-sequence stars that would seem to fall in this category (S-type star, carbon star, PG 1159 star), but I believe the "peculiar" label is most often used regarding main sequence stars.

(star type,metallicity)
Further reading: peculiar star

Referenced by pages:
common envelope
Lambda Boötis star (λ Boo)