Results from the TFTR high-frequency toroidal Mirnov array for detection of modes in the Alfvén range of frequencies

Toroidal Alfvén eigenmodes and other Alfvénic modes have been predicted to be destabilized by the presence of a fusion α population in TFTR and future D-T machines, possibly resulting in significant loss of the fast α population. A new array of Mirnov coils has been added primarily for the measurement of moderate to high toroidal mode numbers. Initial measurements of the n number of ICRF generated toroidal Alfvén eigenmodes modes is presented. The array has also been used to measure the toroidal correlation length of the edge magnetic turbulence.