Equality of Velocity of Gamma-Rays of Opposite Circular Polarization in a Transverse Magnetic Field

Abstract

Results are reported from an investigation of the influence of the magnetic field on the propagation of light. The Mossbauer effect was used in a study on the equality of velocity of gamma rays of opposite circular polarization in a transverse magnetic field. The source, about 80 mc of cobalt- 57 diffused into the iron foil and giving the Mossbauer radiation of 14.3 Kev, and the pure natural iron absorber were placed in front of the two opposite melanex windows on the cyclotron vacuum chamber in which a pressure of 10/sup -5/ mm mercury was maintained through the experiment. The absorber was followed by a PX 130 xenon-filled proportional counter, the output of which was fed into a single-channel pulse height analyzer selecting the 14.3Kev gamma -ray peak. The scaler input was gated with a crystal controlled timing circuit, accurate to better than one part in 10,000. In the course of the experiment, the half-field absorber transmission was compared with the full-field transmission in frequent alternation and the corresponding counting rates, hereafter called HF and FF, recorded. Both HF/FF ratios deviate from unity and there is an increase of absorption at full field. The increase is not due to themore » effect of the magnetic field on the counter. This effect is due to the fact that, although at half field the absorber material reaches a high degree of magnetization, the complete saturation is not yet attained. Thus, there is an increase in absorption when the polarizing and analyzing field changes from its half field value of 1,250 oersteds to the full field value of 2,500 oersteds, when the material has reached the magnetic saturation. (C.H.)« less