Lane Beale edited Experimental Setup.tex  about 10 years ago

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\section{Experimental Setup}  The plasma was created by an inductively coupled RF source operating at a power of 215 W with Helium as the working gas. A voltage sweep was put across a langmuir probe 70 cm from the RF source 10 ms into the afterglow. A magnetic field was applied to the device through the use of two sets of four coaxial magnets created using 59.0 A and 24.5 A currents laid out around the device and resulting in a radially symmetric magnetic field through the device averaging to 63.5 Gauss along the axis.  Waves were generated in the plasma using a waveform generating antenna, in 5 frequencies ranging from 20Mhz to 120Mhz in 20Mhz steps. Measurements for the 20Mhz data run began 5cm away from the source to with 5 measurents taken in the z direction in 2 cm steps. Angular measurements were taken 21 times in 1.3$^\circ$ steps. The same measurements and acquisititons were made lengthwise and in the radial direction, but measurements were taken for 31 different angles, each for a set of frequencies during the 40-100 Mhz data runs. The 120 Mhz data run was taken 15 cm away from the allowed distance to the probe but instead 81 z measurements were taken at 0.37 steps and 51 angular measurements were taken at 1.0$^\circ$ steps. The electric field was measured by an electric dipole probe, as shown a model of which can be seen  in figure 1.