Magnetohydrodynamic Activity in High-β, Currentless Plasmas in Heliotron-E

Electron-cyclotron and neutral-beam heating have been used to produce currentless plasma with $〈\beta 〉\approx \mathrm{}(1-2)\%$ in the Heliotron-$E$ device. For moderately peaked profiles, magnetohydrodynamic activity that peaks at the $t=1\mathrm{}$ surface has been observed. The characteristics of the fluctuations are consistent with theoretical expectations for an $m=1\mathrm{}$ pressure-driven instability. The magnetohydrodynamic activity is associated with particle and energy losses but has not yet been directly linked to global confinement.