Fast Meson Interactions in Nuclear Emulsions. II.π+Mesons

Abstract

${\pi }^{+}$ mesons produced in the exterior proton beam of the Berkeley cyclotron are bent by an auxiliary magnet and detected in Ilford G5 emulsions. These mesons are studied in the same way as were the ${\pi }^{-}$ mesons in Part I of this experiment. Extra care is taken to eliminate protons from the data and a special technique is developed to make more efficient small angle scattering measurements. The average initial energy, 45.5 Mev, is slightly higher than that of the ${\pi }^{-}$ mesons, and the spread in energy is greater. Less than 18 percent of observed track is less than 30 Mev and 98 percent of it is over 22 Mev.