The absolute yields of prompt and delayed fission induced by negative muons in 232 Th, 238 U and 235 U have been measured. The delayed fission yields are much lower than could be predicted from Γ n / Γ f systematics for 15–20 MeV nuclear excitation. The systematics of prompt fission yields are compared with recently obtained photofission data. It is suggested that prompt fission can be used for investigating the channel structure of the fission barrier.
The absolute yields for prompt and delayed fission induced by negative muons in 237 Np, 239 Pu and 242 Pu have been measured and compared with photofission data.
The self-shunted streamer chambers can be used as visualizers of particle tracks and as detectors of event vertices. We discuss the operating conditions of this type of chamber in the presence of a magnetic field, and the features of the hv-pulse generator connected to the chamber. The results in the precision which can be obtained in the reconstruction of the tracks are discussed.
On Track Localization in Selfshunted Helium Filled Streamer Chambers
A helium-filled self-shunted streamer chamber with various admixtures (Ne, Xe, H 2 , CH 4 , H 2 O, α-pinene) is described. The operating conditions have been investigated. A qualitative explanation is presented for the mechanism of the track localization.
Analysis of the Spectator Angular Distributions in d + p ---> p + p + n Reaction at 3.3-GeV/c
The experimental polar angle distribution of the spectator nucleon in the dp to pnp reaction is studied in different intervals of the spectator momentum and four-momentum transfer. The results are compared with those from the impulse model calculations which take account of the ambiguity in the spectator particle identification. Agreement between the calculations and experiment is observed. The final state interaction of two nucleons is also considered.
Shift of the Electronic x-Rays in Heavy Muonic Atoms
Energy shifts of the electronic K X-rays of heavy muonic atoms have been observed. Natural metallic targets of Ta, Ir, Pb, Th and U were used. The shifts amounts to a few hundreds eV. This effect may give rise to a better understanding of muon cascade dynamics.
