Search for spectral variability of  a sample of CP stars and phase relations among light, spectral and magnetic variations.

Tools: spectroscopic observations of HeI l 5876 Å equivalent width variations.

Results from this studies have been published in:

    Variability of the HeI l5876 Å line in early type chemically peculiar stars
     G. Catanzaro, F. Leone, F. A. Catalano
     1999, Astronomy and Astrophysics Supplement Series, 134, 211

Here are some examples from Paper I (click to blow up):

and from Paper II (click to blow up):