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We investigate a peculiar feature at the hottest, blue end of the horizontalbranch of Galactic globular cluster omega Centauri, using the high-precisionand nearly complete catalog that has been constructed from a survey taken withthe ACS on board the HST, that covers the inner 10x10 arcminutes. It is adensely populated clump of stars with an almost vertical structure in theF435W-(F435W-F625W) plane, that we termed "blue clump". A comparison withtheoretical models leads to the conclusion that this feature must necessarilyharbor either hot flasher stars, or canonical He-rich stars --progeny of theblue Main Sequence sub population observed in this cluster-- or a mixture ofboth types, plus possibly a component from the normal-He population hosted bythe cluster. A strong constraint coming from theory is that the mass of theobjects in the "blue clump" has to be very finely tuned, with a spread of atmost only $\sim$0.03Mo. By comparing observed and theoretical star counts alongboth the H- and He-burning stages we then find that at least 15% of theexpected He-rich Horizontal Branch stars are missing from the color-magnitudediagram. This missing population could be the progeny of red giants that failedto ignite central He-burning and have produced He-core White Dwarfs. Ourconclusion supports the scenario recently suggested by Calamida et al. (2008)for explaining the observed ratio of White Dwarfs to Main Sequence stars inomega Centauri.

Hot Horizontal Branch stars in omega Centauri: clues about their origin from the cluster Color Magnitude Diagram