The identification and UBV photometry of the visible component of the Centaurus X-3 binary system

Abstract

The optical component of the pulsating binary X-ray source Cen X-3 is identified with a faint, /V/ = 13.35, heavily reddened variable star lying slightly outside the error box of the 3U catalog. It shows a double-peaked light curve with an amplitude of about 0.12 mag which agrees in both period and phase with the X-ray data. The shallower minimum coincides in time with the X-ray pulsar eclipse. The estimated distance to Cen X-3 is about 8 kpc.