A weak DC magnetic field is applied to an immersed helical resonator antenna in an RF plasma to study the effects of magnetic insulation on potential differences between plasma and antenna within the vacuum chamber. Past research suggests a link between minimizing antenna potential and mitigating self-sputtering effects within the chamber to minimize debris creation. Alteration of particle flux...

A plasma source excited by a double saddle helicon antenna outside the glass vacuum vessel has been modified by inserting a second copper antenna in contact with the plasma through the glass end plate. Both have the same frequency of 13.56 MHz but have a different phase. The immersed antenna is electrically floating, allowing a negative self-bias to form, leading to ion bombardment and sputteri...

An analytical and numerical study for the coupling of a current sheet antenna to a tokamak plasma is presented. The antenna is of finite poloidal and toroidal dimensions and screened from the plasma by a sheath of anisotropic conductivity that shorts out just the toroidal component of the rf field. The excitation of only the fast component of the waves in the ion-cyclotron range of frequencies ...

Investigations on the optimization of feed structures for exciting the slotted line antenna for high-density plasma production are presented. Each feed structure used (except the direct feed) excites a preferred component of the wave electric/magnetic field. It is seen that the efficacy of plasma production using the different feeds depends directly on the relative importance of the field compo...

This paper presents study of a 6.78 MHz RF source with impedance matching network based inductively coupled plasma generator ignition system for an Hion source. Two types of 10 turn RF antenna (solenoid coil) were developed, to couple the RF power to the ignition plasma chamber. The antenna’s electric parameters were measured using Vector Network Analyzer (VNA). A copper conductor of 3 x 4 mm s...

Two-dimensional images of the ionized argon light of a helicon discharge are made both along and across the magnetic field with various antenna configurations. Two antennas, a Nagoya type III and a helical antenna, are used to create a magnetized RF plasma with density in the range n ≤ 5× 1013 cm−3. A CCD camera with a 488 nm bandpass filter is used to image the plasma as magnetic field and pow...

Abstract. The compatibility of ICRF (Ion Cyclotron Range of Frequencies) antenna operation with high-Z plasma facing components (PFCs), needs improvement to keep ICRF as a good candidate for heating and current drive system in a fusion reactor. ASDEX Upgrade (AUG) with its tungsten (W) first wall and ICRF system allows to study ways to do this. A noticeable improvement of the ICRF operation wit...

1. Introduction The studies of linear antenna in anisotropic mediums are important in such applications as radio communication in space, heating of plasma by high-frequency electromagnetic fields, diagnostics of magnetoactive plasma, electromagnetic compatibility of electronic devices, etc. The purpose of the present work is the solution of the problem on excitation of a system of thin impedanc...

A simple model is presented to describe how the radio frequency electromagnetic field modifies plasma density antenna faces in tokamaks. Aside from “off-the-shelf” equations standardly used wave-plasma interaction relying on quasilinear approach, it invokes ponderomotive force presence of confining static magnetic field. The focus dynamics perpendicular Bo Stronger fields result being pushed fu...