Study of Inverted Sawtooth Activities in EAST Plasma

• 作 者: 陈晔斌 胡立群 陈开云 李妙辉
• 机 构: University of Science and Technology of China,Institute of Plasma Physics,Chinese Academy of Science
• 出 处: Plasma Science and Technology
• 发表日期: 2014年03期
• 关键词: EAST inverted monotonic curvature valley camera explained heating hollow appeara

On the EAST tokamak,during whole off-axis LHCD(low hybrid current drive)limiter discharge,inverted sawteeth oscillations on the SXR(soft X-ray camera)signals appear continuously,and no positive sawtooth is observed.It is thought that this phenomenon is caused by the curvature pinch,though it could partly be explained by the electron temperature profile observed on the PHA(soft X-ray pulse height analyzer)system.The off-axis LHCD and Ohmic heating generate a non-monotonic q profile.According to the curvature pinch effect,this q profile leads to a special electron density profile that has a valley ring.The non-monotonic q profile and the special electron density profile lead to this interesting phenomenon.

On the EAST tokamak, during whole off-axis LHCD (low hybrid current drive) limiter discharge, inverted saw tethers oscillations on the SXR (soft X-ray camera) signals appear continuously, and no positive sawtooth is observed. It is thought that that it is caused by the curvature pinch, though it could partly be explained by the electron temperature profile of the PHA (soft X-ray pulse height analyzer) system. off-axis LHCD and Ohmic heating generate a non-monotonic q profile. to the curvature pinch effect, this q profile leads to a special electron density profile that has a valley ring. the non-monotonic q profile and the special electron density profile lead to this interesting phenomenon.