ITER L mode confinement database

This special topic describes the contents of an L mode database that has been compiled with data from Alcator C-Mod, ASDEX, DIII, DIII-D, FTU, JET, JFT-2M, JT-60, PBX-M, PDX, T-10, TEXTOR, TFTR and Tore Supra. The database consists of a total of 2938 entries, 1881 of which are in the L phase while 922 are ohmically heated only (ohmic). Each entry contains up to 95 descriptive parameters, including global and kinetic information, machine conditioning and configuration. The special topic presents a description of the database and the variables contained therein, and it also presents global and thermal scalings along with predictions for ITER. The L mode thermal confinement time scaling, determined from a subset of 1312 entries for which the τ_E,th are provided, is τ_E,th = 0.023I_P^0.96B_T^0.03R^1.83 (R/a)^0.06κ^0.64n̄_e^0.40M_eff^0.20P^-0.73 in units of seconds, megamps, teslas, metres, -, -, 10¹⁹ m^-3, atomic mass units and megawatts.