High density helicon source for beam attenuating target
نویسندگان
چکیده
High density (ne ≥ 4× 1018m−3) helium plasma is produced in a linear device for the development of a neutral helium-beam attenuating target. Radially peaked density profile accompanied by one order of density jump is observed for radio frequency input power higher than the threshold power. The threshold power varies with the external magnetic field. The results suggest that the density jump is caused by the discharge transition from the inductively coupled mode to the helicon mode. Measurement of overall density profile for the axial direction shows the line integrated density is comparable to that required for the neutral helium-beam attenuating target.
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