TY - GEN
T1 - Effect of pellet shots on edge plasma density fluctuations in the Wendelstein 7-X stellarator
AU - the W7-X Team
AU - Édes, L.
AU - Dunai, D.
AU - Zoletnik, S.
AU - Vécsei, M.
AU - Hegedűs, S.
AU - Anda, G.
AU - Takács, R.
AU - Cseh, G.
AU - Stechow, A. V.
AU - Otte, M.
AU - Rahbarnia, K.
AU - Winters, V.
AU - Harris, J.
N1 - Publisher Copyright:
© 2021 47th EPS Conference on Plasma Physics, EPS 2021. All rights reserved.
PY - 2021
Y1 - 2021
N2 - The pellet fuelling potential was studied at Wendelstein 7-X (W7-X) stellarator in the OP1.2b campaign. Unusual observation was made by the PCI diagnostics[1], showing sudden drop of fluctuation level in the core after pellet fuelling. The decreased fluctuation level was accompanied by improved energy confinement. In this paper the edge behaviour was studied in details in this period. The decreased turbulence level was clearly observed in the edge region with the Alkali Beam Emission Spectroscopy (ABES) diagnostic. The spatio-temporal structure of fluctuations were calculated using correlation functions in various periods of the discharge. Multiple diagnostics were used to complete and confirm the results from the analysis of the ABES diagnostic. The time evolution of fluctuation behaviour was characterized by calculating cross-correlations of ABES signals with Phase Contrast Imaging (PCI), H-alpha, Mirnov coil diagnostics signals.
AB - The pellet fuelling potential was studied at Wendelstein 7-X (W7-X) stellarator in the OP1.2b campaign. Unusual observation was made by the PCI diagnostics[1], showing sudden drop of fluctuation level in the core after pellet fuelling. The decreased fluctuation level was accompanied by improved energy confinement. In this paper the edge behaviour was studied in details in this period. The decreased turbulence level was clearly observed in the edge region with the Alkali Beam Emission Spectroscopy (ABES) diagnostic. The spatio-temporal structure of fluctuations were calculated using correlation functions in various periods of the discharge. Multiple diagnostics were used to complete and confirm the results from the analysis of the ABES diagnostic. The time evolution of fluctuation behaviour was characterized by calculating cross-correlations of ABES signals with Phase Contrast Imaging (PCI), H-alpha, Mirnov coil diagnostics signals.
UR - http://www.scopus.com/inward/record.url?scp=85119666971&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:85119666971
T3 - 47th EPS Conference on Plasma Physics, EPS 2021
SP - 956
EP - 959
BT - 47th EPS Conference on Plasma Physics, EPS 2021
PB - European Physical Society (EPS)
T2 - 47th EPS Conference on Plasma Physics, EPS 2021
Y2 - 21 June 2021 through 25 June 2021
ER -
