ELM studies on the COMPASS-D tokamak

A description of the various ELM types observed in single null divertor plasmas in COMPASS-D is given, including type I and type III ELMs in both ECRH and ohmically heated plasmas. Precursor oscillations to both type I and type III ELMs have been observed. The large variation in the precursor mode structure is discussed, as well as models of the effect on the plasma.