Experimental Measurement of Whistler Waves at the LAPTAG high school plasma laboratory
Abstract
The vector magnetic field of whistler waves above and below half the electron cyclotron frequency is measured in 2 dimensions in a 51x31 plane with δz=1cm, δx=1cm, B=B0z<=100 G, and δt=0.4ns. 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 (Frf=625Hz, P<=1kW, τplasma=10ms, τrep=50ms, 10^8<=n<=10^12;cm-3). The three axis dBdt 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. )
- Publication:
-
APS April Meeting Abstracts
- Pub Date:
- February 2010
- Bibcode:
- 2010APS..APR.C1046E