Observations of Rapid Blue Variables--II: U Geminorum

Open Access
Publisher Website
Google Scholar
Abstract
We describe a new model for the binary dwarf nova U Geminorum, based on high time resolution photometric observations during normal light. These demonstrate the nature of the light flickering around the orbit. Flickering disappears during primary eclipse. We suggest that the previously known bright spot in the U Gem system is the source of all flickering during normal light, and that it is situated on the nebulous ring that surrounds the hot component. Infalling material from the cool star, which fills its Roche lobe, provides the energy needed to maintain the bright spot as a stable feature. We interpret primary eclipse as an eclipse of the bright spot plus nebulosity. Then the inclination of the orbit is such that the hot component is not eclipsed. Thus either component can be the source of the dwarf nova outbursts, in contrast with the model proposed by Krzeminski which requires that the seat of eruption be in the cool star.

This publication has 0 references indexed in Scilit: