Atomic Energy of Canada Limited

About: Atomic Energy of Canada Limited is a company organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Neutron & Zirconium alloy. The organization has 4845 authors who have published 4826 publications receiving 102951 citations.

Anisotropic phonon dispersion in GaS

Abstract: The group theoretical analysis of lattice vibrations in GaS and neutron inelastic scattering measurements of acoustic phonons propagating along the Delta , Sigma and T directions are presented. The elastic constants C11, C33, and C44 are derived and the results for the Delta direction are analysed to determine interlayer force constants. The frequencies of the B1 modes along Sigma and T show a weak quadratic dependence on wavevector. A simple interatomic force model is fitted to the phonon frequencies, and the frequency distribution function is calculated. The temperature dependence of the lattice specific heat and of the corresponding Debye temperature is calculated; over a small temperature range the variation of the specific heat is characteristic of a pseudo-two-dimensional solid.

Large Germanium Lithium-Drift p-i-n Diodes for Gamma-Ray Spectroscopy

Abstract: Germanium lithium-ion drift p-i-n diodes with depletion depths up to 11 mm and active volume 6 cm3 have been fabricated from 10 ohm-cm, gallium-doped material using a high-power drift method. Diodes were immersed in chloroform and drifted at ohmic dissipation power levels in the range 50-100 W at 30-50 V D. C. drift bias. Diodes were electrothermally stabilized during drift by the boiling action of the chloroform (B. P. = 61.3°C). Peak power levels of up to 250 W at 200 V bias were obtained at the commencement of the chloroform drift, but were reduced to within the range given above following a rapid increase in leakage current during the first few hours of drift. Diode temperatures were estimated at 10-20°C above the chloroform boiling point. Drift times were typically 500 to 700 hours for depletion depths of 8 and 10 mm respectively. Seven diodes with depletion depths 6-11 mm have been operated as ?-ray spectrometers in vacuum (10-6 mm Hg) at liquid N2 temperatures (77°K) with bias up to 1200 V and leakage currents ~10-9A. Some typical spectral response characteristics are given for diodes used as photoelectric ?-ray spectrometers and the effect of carrier trapping on energy resolution is demonstrated. Resolutions of 3.5 and 8.0 keV on the full-energy peaks of 122 and 1353 keV ?-rays were obtained from a device of average performance (5 cm2 x 7 mm depletion depth). The intrinsic full-energy peak efficiency of a 4.