A measurement of the cosmic-ray source abundance of Ca-40

In this Letter we present the measured charge composition of the galactic cosmic rays from Ar to Ni and the isotopic composition of the elements Ca and Sc. We find that the ratio /sup 40/Ca/Fe at the cosmic-ray source is (5.9 +- 1.9%). This result is in good agreement with the meteoritic value (6.8 +- 1.0%).