New Dimming Events in Southern R Coronae Borealis Stars

Abstract

Abstract This paper reports on photometry of dimming events for three Southern R Coronae Borealis (RCB) stars. Two of these stars have recently entered a dimming phase (IO Nor and V653 Sco), while the other (GU Sgr) is emerging from a dimming event. Low resolution spectra of one of the targets indicates blueshifted Na i D lines, and hydrogen alpha emission. As the number of known RCBs grows, the need to monitor them and detect dimming events at an early stage increases.