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Channeling phenomena are observed for charged particles of momentum up to 250 GeV/c in a germanium crystal. The angular distributions of the channeled particles are compared with theoretical predictions based on a diffusion model. The results indicate additional mechanisms leading to dechanneling of the particles although channeling effects are observed for particles incident at up to several times the critical angle, in contrast with the results from low energy channeling.

Channeling phenomena are observed for positive particles of momentum up to 250 GeV/ c in a germanium crystal. The polar angular distributions of the channeled particles are compared with theoretical predictions based on a diffusion model. The results indicate that at high particle energy there may be additional mechanisms besides those operative at low energy leading to dechanneling of the particles. In spite of this, channeling effects are observed for particles incident at up to several times the critical angle, in contrast with the results from low energy channeling. Statistical equilibrium in the azimuthal angular distribution has also been observed at all measured beam momenta to about twice the calculated channeling critical angle. The breakdown of statistical equilibrium for the 2 cm crystal used occurs at an incident angle 2–3 times smaller than predicted theoretically.

The results of measurements of energy losses of 35-, 100-, and 250-GeV particles channeled through a 2-cm Ge crystal are reported. The energy losses are correlated with the incoming and outgoing particle angles, relative to the channel axis, and the results are compared with existing theories.

Designs are presented for two pre-processors to analyze scattering angles measured with drift-chamber systems for use in precision measurements of channeling effects at high energies.

Channeling of protons and positive and negative pions has been observed in a single crystal of germanium at beam momenta of 35, 100 and 250 GeV/c. Both energy loss and scattering have been measured. The channeling effects agree with observations at lower energies suitably scaled to these high energies. The suppression of inelastic nuclear interactions has been directly observed by monitoring multiple-track events.

Polarization effects in Mossbauer experiments are discussed using an S -matrix and densitymatrix formalism. Equations are derived for both Mossbauer transmission and scattering. The generality of the formalism is demonstrated by extending the discussion to include interference between Mossbauer and electronic scattering.

Signals that cannot be sampled at regular intervals occur in several fields. The techniques of time-series analysis can be useful if the auto-correlation function for irregular functions can be defined. This paper develops heuristic arguments for a proposed definition. This definition has proved useful in semiautomatic measurements of bubble-chamber film at Fermilab.

We have investigated the effects of pulse counting rate on chi-square calculations for the experimental arrangement used in Mossbauer effect studies.