UBC Theses and Dissertations
A low energy Beta-ray spectrometer Brown, Harry
The construction and preliminary tests of a Beta-ray spectrometer designed to work at energies below 100 Kev is described. The instrument is of the small semi-circular focussing type using four counter pairs. The design is for reasonably high resolution and high transmission angle. The magnetic field is produced by a combination of plane coils designed to maintain field homogeneity to better than 1%. The magnet current is held to 1 part in 10,000 by means of an electronic circuit composed of D.C. and A.C. amplification stages controlling the grids of a bank of 6AS7 double triodes in series with the magnet windings. The counter windows and source backing are collodion films of the order of 0.1 μ. Work on this instrument is continuing.