Measurement of Magnetic Field in a Laboratory Plasma by Thomson Scattering of Laser Light

A 2.7-Å band of the spectrum of ruby-laser light scattered by a plasma (20 eV, ${10}^{15}$ electrons/${\mathrm{cm}}^3$) in the presence of a magnetic field of about 15 kG has been isolated and passed through a 0.1-Å resolution interferometer. Magnetic modulation of the spectrum has been detected. There is reasonable agreement between the field strength calculated from the modulation and that measured by Faraday rotation.