Session NP1 - Poster Session VIII.
POSTER session, Wednesday afternoon, October 25
Exhibit Hall AB, Qu\'{e}bec City Convention Centre
The n=1 RWM has been clearly observed in DIII-D when the beta exceeds the predicted no-wall beta limit. The RWM onset is strongly affected by plasma rotation and static error fields. At values of beta above the no-wall beta limit, the static error field is observed to be amplified by plasma response leading to a more rapid decay of toroidal rotation and eventual RWM onset. The RWM has been controlled by an active feedback stabilization using six driven saddle coils on the midplane, and powered as three independent n=1 pairs. The RWM amplitude is monitored by a saddle coil sensors measuring the radial magnetic flux through the vacuum vessel under each driver coil. Stabilization of the RWM above the no-wall beta limit has been achieved for more than 30 wall times using ``mode control'' feedback logic and 10 wall times using ``smart shell'' feedback logic. These results are in agreement with predictions of the VALEN finite element 3-D feedback code.