Experimental Measurement of Whistler Waves at the LAPTAG high school plasma laboratory

The vector magnetic field of whistler waves above and below half the electron cyclotron frequency is measured in 2 dimensions in a 51$\times $31 plane with $\delta z=1$cm, $\delta x=1$cm, $B=B_{0z} \le 100$ G, and $\delta t=0.4$ns. The experiments are performed in a high school plasma physics lab featuring a 1.5 meter long, 30 cm diameter pulsed, inductively coupled RF Argon plasma ($F_{rf} =625$Hz, $P\le 1$kW, $\tau _{plasma} =10$ms, $\tau _{rep} =50$ms, $10^8\le n\le 10^{12}\;\mbox{cm}^{-3})$. The three axis $\frac{d\vec {B}}{dt}$ probe, single loop launch antenna and signal detection amplifiers were constructed by the high school students. A phase-locked tone burst is generated at a fixed frequency and launches a whistler wave; each data plane takes six hours to acquire. Data is acquired with a computer controlled 2D drive and a networked 2.5 Gs (440 MHz) digital oscilloscope. The experiment is conducted in the quiescent afterglow 1 to 20 ms after the RF plasma production is terminated. The plasma density is also measured at each position. We present maps of the phase fronts of the wave, and group velocity as a function of frequency together with movies.