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Title: Dynamics of the pedestal transport during edge localized mode cycles at ASDEX Upgrade

Journal Article · · Plasma Physics and Controlled Fusion

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. The dominant mechanism for the additional energy transport in the electron channel that could cause the delay in the electron temperature gradient ($${\rm{\nabla }}{T}_{e}$$) 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 $${\rm{\nabla }}{T}_{e}$$ 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.

Research Organization:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE; EUROfusion Consortium; H2020 Marie-Sklodowska Curie Programme; European Research Council (ERC)
Contributing Organization:
The ASDEX Upgrade Team
Grant/Contract Number:
AC02-09CH11466
OSTI ID:
1598047
Alternate ID(s):
OSTI ID: 23028691
Journal Information:
Plasma Physics and Controlled Fusion, Journal Name: Plasma Physics and Controlled Fusion Journal Issue: 2 Vol. 62; ISSN 0741-3335
Publisher:
IOP ScienceCopyright Statement
Country of Publication:
United States
Language:
English

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