Center for Astrophysics,
Harvard College Observatory and Smithsonian Astrophysical Observatory, Cambridge,
Mass.
Abstract
2677 magnitudes of the hot
massive variable star X Persei, the prime optical candidate for the X-ray
source 3U 0352+30, have been obtained from blue plates in the Harvard
collection taken between 1894.9 and 1975.1. We have analyzed these data for
periods from 0.5 to 180 days and find no periodic component of brightness with
full sinusoidal amplitude ? 0.05 mag. Other period searches, from 550 to 618
days and from 10.75 to 11.75 hours, likewise gave negative results for full amplitudes
of ? 0.07 mag.