DIII-D RESEARCH OPPORTUNITIES FORUM FOR THE 2008 EXPERIMENTAL CAMPAIGN
Login | Review | Submit | Logout | Help
Questions about this website? Contact Andrew LeBlanc Questions about ROF? Contact Chuck Greenfield
| Title | 464: Measurement of RFA using the SXR Diagnostic | ||
| Name: | Matthew Lanctot ( |
Affiliation: | Columbia University |
| Research Area: | RWM Physics | Presentation time: | Not requested | Co-Author(s): | Holger Reimerdes, Andrea Garofalo, Michael J. Schaffer |
| Description: | We will measure the internal mode structure of the plasma response (RFA) to externally applied magnetic field perturbations using the tools/techniques of active MHD spectroscopy and the SXR toroidal cameras. | ||
| Experimental Approach/Plan: | Apply slowly rotating (5-100 Hz) n=1 magnetic field perturbations with the Icoil while using feedback control of betan or control of the toroidal rotation. Analyze SXR data from these discharges to calculate a radial profile of the n=1 plasma fluid displacement. Compare these results with calculations of the mode structure of the external kink mode obtained from ideal MHD stability codes. Apply rotating error field in co and counter directions with respect to plasma rotation. Use neutral beam feedback control of the toroidal rotation to ramp down the rotation while applying the field to evaluate the effects of shielding. Scan beta and Icoil currents to maximize plasma response. | ||
| Background: | To date, on DIII-D, only arrays of magnetic sensors have been successfully used to investigate the RFA. Our goal is to extend the well-established methods of active MHD spectroscopy to include additional diagnostics. The newly refurbished SXR toroidal cameras can detect internal perturbations to the flux surfaces that result from externally applied fields. A more complete understanding of the internal RFA structure may help to elucidate the relationship between RFA and the RWM. | ||
| Resource Requirements: | -- | ||
| Diagnostic Requirements: | MSE, CER, SXR, ECE, magnetics | ||
| Analysis Requirements: | CERFIT | ||
| Other Requirements: | -- | ||
Print this page