Coordinated EXOSAT and Spectroscopic Observations of Flare Stars and Coronal Heating

Abstract

We present some preliminary results of simultaneous monitoring of the two flare stars, UV Ceti and EQ Peg with EXOSAT and ground based optical spectro-scopy. A strong correlation, found between the Hγ emission and the soft X-ray flux, over several hours of observation of UV Ceti, suggests that much of the low level X-ray flux which has previously been considered `quiescent', in fact derives from small flare events. The implication is that coronal heating in M type dwarfs may result directly from the frequent occurrence of micro-flares.