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Using a stack of multiwire proportional chambers with interspersed absorbers, we have measured the range distributions of low energy pions and muons, and have obtained the mean range and range straggling (deviation about the mean) and compared them with the calculations of Janni. The percent differences between the actual incident energies and those calculated from the mean range were 2.37% for 39.3 MeV μ+, 1.13% for 37.6 MeV π+, 0.608% for 33.0 MeV π+, 0.303% for 33.0 MeV π−, and 0.854% for 37.6 MeV π−. These differences are less than the expected errors in the range calculations. The ratios of the observed to the predicted range straggling for the corresponding particles and energies were 1.0, 1.2, 1.4, 1.4, and 1.2 (accurate to about ±10%).

The linear polarization of the coherent bremsstrahlung from a single crystal of silicon was measured by observing the one-dimensionally projected angles of electron and positron pairs. The coherent bremsstrahlung was produced by injecting the 1153 MeV electrons to the silicon crystal nearly along the [110] axis. The emission angles, η + and η − , of pair particles were determined event by observing their tracks with a set of four wire spark chambers. From the ( η + , η − ) distribution of events, the polarization of photons was evaluated. The obtained polarization was consistent with the calculated values, and the technique gives a new approach to the measurement of the linear polarization of photons.

We have simultaneously measured the range and multiple scattering of muons of kinetic energies between 9 and 25 MeV from foils of steel, aluminum, and polyethylene. We have expressed, after Moliere, the root-mean-square projected angle as: ϴ rms proj = A(L L rad ) 1 2 15(pv)−1 where L is the foil thickness, L rad the foil radiation length, p the muon momentum in MeV/ c , and v the muon velocity in units of c . We find that in this energy range A = 1.09 ± 0.02.

We have measured the multiple scattering of low-energy muons from foils of CH 2 , Al and galvanized Fe. The data is compared with theory.