@article{feef9624f1d8425eaba9610654f3b410,
title = "Inter-ELM evolution of the edge current density in JET-ILW type i ELMy H-mode plasmas",
abstract = "Recent studies (Maggi et al 2015 Nucl. Fusion 55 113031; Maggi et al 2017 Nucl. Fusion 57 116012) have shown that on JET with the Be/W ITER-like wall (JET-ILW) in high β discharges with high D2 gas rates, the inter-ELM temperature pedestal growth is saturated half way through the ELM cycle, leading to plasmas with reduced confinement, and that the linear MHD stability of these pedestals is inconsistent with the peeling-ballooning paradigm (Snyder et al 2002 Phys. Plasmas 9 2037-43; Wilson et al 2002 Phys. Plasmas 9 1277-86). In this paper, the inter-ELM evolution of the edge current density is investigated in a wide range of type I ELMy H-modes on JET-ILW. It is found that in discharges at a low gas rate, the peak edge bootstrap current continuously increases until the ELM crashes, while it saturates during the ELM cycle at high gas rates. The effect of current diffusion on the build-up of the edge current inter-ELM is assessed by simulating the Ohmic current contribution with the JETTO transport code. The simulations indicate that current diffusion contributes little to the time evolution of the total edge current in the second half of the ELM cycle and the total current is dominated by the bootstrap current. Therefore, current diffusion does not explain why JET-ILW type I ELMy pedestals at a high gas rate and high βN are found to be stable to peeling-ballooning modes.",
keywords = "bootstrap current, current diffusion, edge current, ELMs, H-mode, JET-ILW, pedestal",
author = "Laszlo Horvath and C.F. Maggi and F.J. Casson and V. Parail and L. Frassinetti and F. Koechl and S. Saarelma and M.G. Dunne and K.J. Gibson and X. Litaudon and S. Abduallev and M. Abhangi and P. Abreu and M. Afzal and Aggarwal, {K. M.} and T. Ahlgren and Ahn, {J. H.} and Leena Aho-Mantila and N. Aiba and Markus Airila and R. Albanese and V. Aldred and D. Alegre and E. Alessi and P. Aleynikov and A. Alfier and A. Alkseev and M. Allinson and B. Alper and E. Alves and G. Ambrosino and R. Ambrosino and L. Amicucci and V. Amosov and Sund{\'e}n, {E. Andersson} and M. Angelone and M. Anghel and C. Angioni and L. Appel and C. Appelbee and P. Arena and M. Ariola and H. Arnichand and S. Arshad and Antti Hakola and Aaro J{\"a}rvinen and Juuso Karhunen and H.T. Kim and H.S. Kim and Seppo Koivuranta and Aki Lahtinen and Jari Likonen and Y. Liu and T. Makkonen and H. Nordman and Antti Salmi and M.I.K. Santala and Paula Sir{\'e}n and Tuomas Tala and {JET Contributors}",
note = "Funding Information: The authors would like to thank J Hobirk, I Lupelli, T Osborne, E Solano and G Szepesi for fruitful discussions. The authors are grateful to E Belli and J Candy for providing access to the NEO code. This work was supported by the Engineering and Physical Sciences Research Council (EP/ L01663X/1). This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Publisher Copyright: {\textcopyright} 2018 York Plasma Institute.",
year = "2018",
month = jun,
day = "13",
doi = "10.1088/1361-6587/aac7a9",
language = "English",
volume = "60",
journal = "Plasma Physics and Controlled Fusion",
issn = "0741-3335",
publisher = "Institute of Physics IOP",
number = "8",
}
