A low-level activation technique for monitoring thermonuclear fusion plasma conditions.
Optimisation of the confinement and sustainability of a thermonuclear plasma requires methods to monitor processes in the plasma. In this work three materials were used as activation targets (Ti, MgF2 and a TiVAl compound). They were placed inside the joint European Torus (JET) vacuum chamber. Certain gamma-ray emitting radionuclides (7Be, 54Mn, 56Co, 57Co, 58Co and 46Sc) were measured using ultra low-level gamma-ray spectrometry in an underground laboratory 1-2 months after activation. They were found to arise from neutron activation of bulk sample material and surface contaminants sputtered from other Tokamak parts. Decision thresholds for some activation products were determined in order to aid in giving upper bounds for the flux of charged particles.
EC-JRC-IRMM, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium.
Joël
J
Gasparro
Mikael
M
Hult
Georges
G
Bonheure
Peter N
PN
Johnston
D000465:Algorithms; D005720:Gamma Rays; D005740:Gases / Q000032:analysis*; D006358:Hot Temperature; D008832:Microchemistry / Q000379:methods*; D009681:Nuclear Fusion; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods*; D011868:Radioisotopes / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013051:Spectrometry, Gamma / Q000379:methods*
D005740:Gases; D011868:Radioisotopes