L–H transition threshold studies in helium plasmas at JET. (22nd October 2021)

• Record Type: Journal Article
• Authors: Solano, E.R.; Birkenmeier, G.; Delabie, E.; Silva, C.; Hillesheim, J.C.; Boboc, A.; Carvalho, I.S.; Carvalho, P.; Chernyshova, M.; Craciunescu, T.; de la Luna, E.; Fontdecaba, J.M.; Henriques, R.; Jacquet, P.; Jepu, I.; Kappatou, A.; King, D.; Lennholm, M.; Lerche, E.; Litherland-Smith, E.; Loarte, A.; Maslov, M.; Parra Diaz, F.; Parail, V.; Pawelec, E.; Rimini, F.G.; Shaw, A.; Siren, P.; Szepesi, G.; Štancar, Ž.; Tholerus, E.; Vartanian, S.; Viola, B.; Weisen, H.; JET Contributors, ;
• Is Part Of: Nuclear fusion. Volume 61:Number 12(2021)
• Publication Date: 2021-10-22
• Subjects: helium -- L–H transition -- tokamak; Nuclear fusion -- Periodicals; 621.48405
• DOI: 10.1088/1741-4326/ac2b76
• Languages: English
• ISSNs: 0029-5515

Abstract

Abstract: We present a study of the power threshold for L–H transitions ( P LH ) in almost pure helium plasmas, obtained in recent experiments at JET with an ITER-like wall (Be wall and W divertor). The most notable new result is that the density at which P LH is minimum, n ¯ e, min, is considerably higher for helium than for deuterium and hydrogen plasmas. We discuss the possible implications for ITER in its pre-fusion operating power phase.