Contrasting H-mode behaviour with fuelling and nitrogen seeding in the all-carbon and metallic versions of JET

A. Boboc, S. Brezinsek, M. Brix, M. Clever, R. Coelho, J.W. Coenen, I. Coffey, P.C. da Silva Aresta Belo, S. Devaux, P. Devynck, T. Eich , R.C. Felton, J. Flanagan, L. Frassinetti, L. Garzotti, M. Groth, S. Jachmich, A. Jarvinen, E. Joffrin, M.A.H. Kempenaars, U. Kruezi , K.D. Lawson, M. Lehnen, M.J. Leyland, Y. Liu, P.J. Lomas, C.G. Lowry, S. Marsen, G.F. Matthews, G.K. McCormick, A.G. Meigs, A.W. Morris, R. Neu, I.M. Nunes, M. Oberkofler, F.G. Rimini, S. Saarelma, B. Sieglin, A.C.C. Sips, A. Sirinelli , M.F. Stamp , G.J. van Rooij, D.J. Ward , M. Wischmeier and JET EFDA contributors EFDA–JET–PR(13)18