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Ccunts / min * yA
Figurę 1*- Neutron yisld from a heavy icc target and frow the copper
bćtoking. Curve 1: number of counts for a 100 keV~thick hea-vy ice target. Curve 2: nuiaber of counts frora tbe copper support for a clGan, new target backing, obtained in the same ezperimental oonditions as curve 1. Curve 3: ratio of curve 1 to curve 2.