148
edits
TJ-II: Plasma turbulence and cryogenic pellet injection: Difference between revisions
TJ-II: Plasma turbulence and cryogenic pellet injection (view source)
Revision as of 13:58, 10 October 2019
, 10 October 2019→Description of the activity
| Line 12: | Line 12: | ||
== Description of the activity == | == Description of the activity == | ||
Cryogenic pellet injection (PI) is widely used to fuel the core of magnetic confinement plasmas. PI can also serve as a plasma diagnostic, for example to locate fast-electron populations or to shed new light on plasma turbulence. For instance, preliminary studies on the effects of hydrogen pellets on radial electric fields, Er, and turbulence in Electron Cyclotron Resonance Heated (ECRH) discharges in TJ-II revealed that the level of core turbulence is reduced strongly for a short time scale (1 ms) after PI, this being followed by an increase in the evolution of plasma density and the recovery of the electron temperature. | Cryogenic pellet injection (PI) is widely used to fuel the core of magnetic confinement plasmas. PI can also serve as a plasma diagnostic, for example to locate fast-electron populations or to shed new light on plasma turbulence <ref> K. J. McCarthy, et al, Plasma Phys. Control Fusion 61 (2019) 014013 </ref>. For instance, preliminary studies on the effects of hydrogen pellets on radial electric fields, Er, and turbulence in Electron Cyclotron Resonance Heated (ECRH) discharges in TJ-II revealed that the level of core turbulence is reduced strongly for a short time scale (1 ms) after PI, this being followed by an increase in the evolution of plasma density and the recovery of the electron temperature.<ref> A. Zhezhera, et al., "Search for physical mechanisms that lead to increased turbulence following pellet injection in the stellarator TJ-II, 44th EPS Conf. Plasma Physics (2017) Belfast, Ireland, P2.171"</ref> | ||
Goal: To study the effects of cryogenic pellets on Er and on plasma turbulence across the TJ-II. | Goal: To study the effects of cryogenic pellets on Er and on plasma turbulence across the TJ-II. | ||
| Line 22: | Line 22: | ||
Plasma scenarios: Injection into low-density and medium-density ECRH plasmas with line-averaged electron density of ≤4x1018 m-3 and of 4 to 5.5x1018 m-3. | Plasma scenarios: Injection into low-density and medium-density ECRH plasmas with line-averaged electron density of ≤4x1018 m-3 and of 4 to 5.5x1018 m-3. | ||
Expected outcome: The evolution and characterization of plasma turbulence before, during and after pellet injection. | Expected outcome: The evolution and characterization of plasma turbulence before, during and after pellet injection. | ||
== International or National funding project or entity == | == International or National funding project or entity == | ||