Report providing detail measurements and percentages in charts, using three statistical parameters, for amplitude-probability distributions of atmospheric radio noise.

This report is a working document of the UB AEC Nuclear Cross Sections Advisory Group and is issued about twice a year for the purpose of stimulating important cross section measurements. The requests listed in this report have originated from various Atomic Energy Commission contractors, the Advisory Committee on Reactor Physics, and the Nuclear Cross Sections Advisory Group. The distribution is limited to members of the US Nuclear Cross Sections Advisory Group (NCSAG), the US Advisory Committee on Reactor Physics (ACRP), the Tripartite Nuclear Cross Sections Committee (TNCC), the European-American Nuclear Data Committee (EANDC), to US AEC off-site contractors, and to the requestors and measurers of the cross sections listed in this report. The contents of this document are not to be republished in part or in full without special permission of the chairman of the NCSAG, The unpublished data which appear in this report must not be quoted in publications without permission of the experimenter.

An experiment was performed at the ORR in order to find a good fission chamber location. Two locations on the pool side of the reactor tank were explored with a one inch diameter fission chamber. The thermal neutron flux attention was found to vary nearly exponentially with distance, and no shadowing effect could be seen during a reactor startup. The fission products high gamma flux could be discriminated without difficulties. Both positions seem to be adequate to locate a reactor control fission channel.

The relative yield of neutral photopions from various elements was determined as a function of the quantum limit energy of the Berkeley synchrotron. Single decay photons from neutral pions were observed at 45, 90, and 135 deg to the incident bremsstrahlung in the laboratory system. Mean free paths for neutral pions in nuclear matter were obtained, an optical model prediction of the photopion yields based upon pion-nucleus scattering data was confirmed, and the presence of coherent pion production in the forward direction was detected.