Open AccessDynamics of the pedestal transport during edge localized mode cycles at ASDEX Upgrade
Author(s) -
E. Viezzer,
M. Cavedon,
P. Cano-Megias,
E. Fable,
E. Wolfrum,
D. J. Cruz-Zabala,
P. David,
R. Dux,
R. Fischer,
G. Harrer,
F. M. Laggner,
R. M. McDermott,
U. Plank,
T. Pütterich,
M. Willensdorfer
Publication year - 2020
Publication title -
plasma physics and controlled fusion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.328
H-Index - 111
eISSN - 1361-6587
pISSN - 0741-3335
DOI - 10.1088/1361-6587/ab5b1d
Subject(s) - asdex upgrade , physics , electron , atomic physics , tokamak , plasma , nuclear physics
The dynamic behaviour of the ion and electron energy, particle and momentum transport measured during type-I edge localized mode (ELM) cycles at ASDEX Upgrade is presented. Fast measurements of the ion and electron temperature profiles revelead that the ion and electron energy transport recover on different timescales, with the electrons recovering on a slower timescale (Cavedon et al 2017 Plasma Phys. Control. Fusion 59 105007). The dominant mechanism for the additional energy transport in the electron channel that could cause the delay in the electron temperature gradient ( ∇ T e ) recovery is attributed to the depletion of energy caused by the ELM. The local sources and sinks for the electron channel in the steep gradient region are much smaller compared to the energy flux arriving from the pedestal top, indicating that the core plasma may dictate the local dynamics of the ∇ T e recovery during the ELM cycle. A model for the edge momentum transport based on toroidal torque balance that takes into account the existence of poloidal impurity asymmetries has been developed. The analysis of the profile evolution during the ELM cycle shows that the model captures the dynamics of the rotation both before the ELM crash and during the recovery phase.