TY - JOUR
T1 - Experimental comparison of recycling and pumping changes during resonant magnetic perturbation experiments at low and high collisionality in DIII-D
AU - Unterberg, E. A.
AU - Brooks, N. H.
AU - Evans, T. E.
AU - Fenstermacher, M. E.
AU - Hillis, D. L.
AU - Maingi, R.
AU - Mordijck, S.
AU - Moyer, R. A.
AU - Osborne, T. H.
AU - Petrie, T. W.
AU - Watkins, J. G.
PY - 2009/6/15
Y1 - 2009/6/15
N2 - Resonant magnetic perturbations (RMPs) have been shown to successfully suppress edge localized modes (ELMs) in the DIII-D tokamak. A previous study of target plate conditions highlighted differences in RMP discharges between low and high electron collisionality, νe*, operation in DIII-D. This paper reports on a systematic study of the electron density pump-out associated with the turn-on of the RMP over a wide range of operating conditions in DIII-D, including shapes and collisionalities similar to those anticipated in ITER. It is shown that the pump-out magnitude, Δne, has an upper envelope that is inversely proportional to the pedestal νe*. The particle decay times, which are calculated based on global D2 particle balances, show an increase as the pedestal νe* is increased. Both results are suggestive that the underlying physics mechanism is an increase in edge particle transport and/or that wall depletion is playing a role in the pump-out magnitude.
AB - Resonant magnetic perturbations (RMPs) have been shown to successfully suppress edge localized modes (ELMs) in the DIII-D tokamak. A previous study of target plate conditions highlighted differences in RMP discharges between low and high electron collisionality, νe*, operation in DIII-D. This paper reports on a systematic study of the electron density pump-out associated with the turn-on of the RMP over a wide range of operating conditions in DIII-D, including shapes and collisionalities similar to those anticipated in ITER. It is shown that the pump-out magnitude, Δne, has an upper envelope that is inversely proportional to the pedestal νe*. The particle decay times, which are calculated based on global D2 particle balances, show an increase as the pedestal νe* is increased. Both results are suggestive that the underlying physics mechanism is an increase in edge particle transport and/or that wall depletion is playing a role in the pump-out magnitude.
UR - http://www.scopus.com/inward/record.url?scp=67349239680&partnerID=8YFLogxK
U2 - 10.1016/j.jnucmat.2009.01.052
DO - 10.1016/j.jnucmat.2009.01.052
M3 - Article
AN - SCOPUS:67349239680
SN - 0022-3115
VL - 390-391
SP - 486
EP - 489
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
IS - 1
ER -