A New Phenomenon in the Spectrum of Sigma Orionis E

A broad, variable emission has been found at Ha in the spectrum of the helium-rich star cr Ori E. The feature is a Woff-Rayet-like band of maximum width near 1800 km 1, which fills in the deep Ha absorption and reaches maximum intensities of nearly 30 percent above the continuum on either side. The emission intensity undergoes large variations with a time scale of a few hours. Radial-velocity measures do not establish binary motion, although a low-mass companion cannot be excluded. The nature of the energetic circumstellar activity reported, and its relationship to the helium anomaly, remain to be determined. SnUect headings: circumstellar shells - early-type stars - spectrum variables