4.8-SECOND Pulsed X-Rays from Centaurus X-3 at Energy Greater than 7 KEV

We searched the hard X-ray data, from the 080-7 satellite, for the 4.8-second pulsations detected by Uhuru at lower energies. A pulse with a 4.841973 + 0.000009 s period was found in the 7-11 keV range from 1971 December 18.0 to 21.4 observations, with a ratio of pulsed to total flux of 45 + 10 percent. In the 11-22 keV range, 2 a upper limits were 80 percent pulsed fraction assuming an 80 percent ON duty cycle. For two other intervals (1971 December 21.4-25.8 and 1972 January 22.9-26.0), we obtained only 2 a upper limits of percent pulsed fraction over the entire 7-22 keV range, again assuming an 80 percent ON duty cycle. Subject heading: X-ray sources