Diagnostics Of Detached Plasmas Using High-n Lines And Continuum Spectra Of D and He.

A Stark line shape code has been coupled to a collisional-radiative model and to an analytical model for the merging into the continuum of the Balmer lines. The coupled codes have been used for temperature and density diagnostics of detached plasmas. In contrast with the occupation probability and the lowering of the continuum edge approaches, the analytical line merging model used here consists in the use of Lorentzian profiles for highly excited Balmer transitions of deuterium. In addition, high-n helium lines (1s2p-1snl) up to n=12 observed in the JET divertor have been preliminary analyzed. The intensities of these experimental helium lines decrease more rapidly with the upper state nl than the intensities calculated with state populations at local thermodynamic equilibrium (LTE). [ABSTRACT FROM AUTHOR]