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We continue to explore the accretion model of the massive binary system etaCarinae by studying the anomalously high He II 4686 line. The line appears justbefore periastron and disappears immediately thereafter. Based on the He II4686 line emission from O-stars and their modeling in the literature, wepostulate that the He II 4686 line comes from the acceleration zone of thesecondary stellar wind. We attribute the large increase in the line intensityto a slight increase in the density of the secondary stellar wind in itsacceleration zone. The increase in density could be due to the ionization andsubsequent deceleration of the wind by the enhanced X-ray emission arising fromthe shocked secondary wind further downstream or to accretion of the primarystellar wind. Accretion around the secondary equatorial plane gives rise tocollimation of the secondary wind, which increases its density, hence enhancingthe He II 4686 emission line. In contrast with previous explanations, thepresently proposed model does not require a prohibitively high X-ray flux todirectly photoionize the He.Comment: ApJ, in pres

Accretion onto the Companion of η Carinae during the Spectroscopic Event. III. The Heiiλ4686 Line