Sensitivity to Error Fields in NSTX High Beta Plasmas [report]

Jong-Kyu Park, Jonathan E. Menard, Stefan P. Gerhardt, Richard J. Buttery, Steve A. Sabbagh, Steve E. Bell, Benoit P. LeBlanc
2011 unpublished
It was found that error field threshold decreases for high β in NSTX, although the density correlation in conventional threshold scaling implies the threshold would increase since higher β plasmas in our study have higher plasma density. This greater sensitivity to error field in higher β plasmas is due to error field amplification by plasmas. When the effect of amplification is included with ideal plasma response calculations, the conventional density correlation can be restored and threshold
more » ... ored and threshold scaling becomes more consistent with low β plasmas. However, it was also found that the threshold can be significantly changed depending on plasma rotation. When plasma rotation was reduced by non-resonant magnetic braking, the further increase of sensitivity to error field was observed.
doi:10.2172/1062663 fatcat:3aoxpcwrpnhirpm5c2cy2r6vse