SPECTROSCOPIC CHANGES OF THE MAGNETIC CP STAR GAMMA-EQUULEI

From an analysis of some new spectroscopic observations of the magneti c CP star gamma Equ we derived an effective magnetic field of -930 +/- 150 G and a surface magnetic field of 4000 G. The magnitude of the ef fective field is compatible with a variation of the field on a time sc ale of a little more than 70 years. The temporal behaviour of the magn etic field is explained by the superposition of a dipole and quadrupol e and the model of the oblique rotator. Surprisingly a few radial velo city values differ from the expected ones by about 10 km/s.