CIOP   05384
CENTRO DE INVESTIGACIONES OPTICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A spectroscopic study of forbidden transitions of noble gases in tokamaks
Autor/es:
C.J.B. PAGAN; M. MACHIDA; J. REYNA ALMANDOS; M. RAINERI; M. GALLARDO
Lugar:
Prague
Reunión:
Congreso; 25th Symposium on Plasma Physics and Technology; 2012
Resumen:
Argon and Krypton has been used for plasma diagnostics and as plasma coolant in many tokamaks around the world. Nevertheless, there is a great lack of information concerning these spectra, mainly when considering transitions in visible and ultraviolet for intermediate degrees of ionization, as that produced by forbidden transitions. Most of the information available for Ar III-VII and Kr II-VIII are in vacuum-ultraviolet, whose detection techniques are more complicated than that for visible. Visible lines occur in Ar or Kr spectra due to magnetic dipole or electric quadrupole transitions, but only a few lines were observed up to now: considering all degrees of ionization, from 4967 observed lines of Argon, only 50 are due to forbidden transitions. For Krypton, only 35 of the 4426 observed lines are from forbidden transitions. Krypton should be used in the ITER tokamak as a coolant gas in the plasma edge, which emphasizes the importance of that study for future applications in fusion plasma technology. Because of the low pressure of the tokamak plasmas, forbidden lines are possible to be observed. In present work, we will add small portions of krypton in the NOVA tokamak at University of Campinas (UNICAMP, Brazil), looking for intra-configuration magnetic dipole transitions for Kr V, never before observed in laboratory. We have special interest in the 1S0-1D2 transition at 5133 Å, 1D2-3P1 transition at 6258 Å, and 1S0-3P2 transition at 3134 Å, observed in astrophysical plasmas but never confirmed in laboratory. We calculated the transition probabilities for Kr V transitions, using Hartree-Fock and Dirac-Fock methods in order to estimate line intensities during the laboratory experiments.