THE HE-3/ (HE-3+HE-4) RATIO IN PRIMARY COSMIC RADIATION

The rtio equals He3 He3 He4 is determined using a nuclear emulsion stack exposed at the geomagnetic latitude 61 N on Augut 3, 1958 under 3.8 gmssq. cm. of matter. The ratio R found at the top of the atmosphere is 0.31 or - 0.08 for the same energy per nucleon 160-355 ev and 0.33 or - 0.08 for the same rigidity 1.05 - 1.48 Bv. These values are lower than a previous observation, but in agreement within the statistical errors, thus implying little or no time variation in the ratio R over a period of one year. Author