ICRF heating in the Alcator C-Mod tokamak
ICRF heating experiments have been carried out in the Alcator C-Mod tokamak at power levels up to 3.5 MW. Features of Alcator C-Mod include high density operation, molybdenum plasma facing components, and a closed divertor configuration. The heating is accomplished with two two-strap antennas each run with dipole phasing at 80 MHz in deuterium plasmas with a hydrogen minority resonant at 5.3 T. Plasmas with {ital T}{sub {ital i}}=4 keV and {ital T}{sub {ital e}}=5 keV at {bar {ital n}}{sub {ital e}}=1{times}10{sup 20} m{sup {minus}3} have been produced with 3.5 MW of heating power. The heating has been shown to be strongest with a low minority concentration (1{endash}5{percent}) and the resonance on axis. For {bar {ital n}}{sub {ital e}}{approx_gt}2{times}10{sup 20} m{sup {minus}3}, the central {ital Z}{sub eff} remains below 1.5 with more than 2.5 MW of applied rf power. L-mode confinement scaling is observed both for ohmic and ICRF-heated plasmas with some deterioration at higher densities. H-mode transitions have been produced with the threshold for ELM-free H-modes at or below the ASDEX/DIII-D scaling. Enhanced confinement with strongly peaked density profiles has been achieved by lithium pellet injection. Applying 3 MW of rf power shortly after pellet penetration produces {ital T}{sub {ital i}0}=4 keV and a factor of five increase in fusion neutron rate (up to 9{times}10{sup 13} s{sup {minus}1}), and an H-mode transition. {copyright} {ital 1996 American Institute of Physics.}
- Research Organization:
- Massachusetts Institute of Technology
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC02-78ET51013
- OSTI ID:
- 285214
- Report Number(s):
- CONF-9505105--
- Journal Information:
- AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 355; ISSN 0094-243X; ISSN APCPCS
- Country of Publication:
- United States
- Language:
- English
Similar Records
ICRF heating experiments on the PLT tokamak
Fast-wave ion cyclotron resonance heating experiments on the Alcator C tokamak