A two-component X-ray spectrum from SMC X-1.

HEAO 1 A-2 and Einstein Solid State Spectrometer (SSS) observations of SMC X-1 are presented. An unpulsed soft component is found with a blackbody temperature of 0.16 keV and an area for the emission region of 10 to the 15th to 10 to the 17th sq cm. The hard X-ray component is pulsed; the phase-averaged spectrum is a power law with alpha of about 0.5 up to 17 keV, above which it steepens. The SSS sets an upper limit of less than 4 x 10 to the 21st H/sq cm to any absorption, and is consistent with that expected from the wind of Sk 160. Absorption dips with a timescale of several hundred seconds are seen immediately following an eclipse exit, and are probably caused by inhomogeneities in the wind of Sk 160.