The GRIFFIN facility for Decay-Spectroscopy studies at TRIUMF-ISAC

Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei, GRIFFIN, is a new high-efficiency γ-ray spectrometer designed for use in decay spectroscopy experiments with low-energy radioactive ion beams provided by TRIUMF\u27s Isotope Separator and Accelerator (ISAC-I) facility. GRIFFIN is composed of sixteen Compton-suppressed large-volume clover-type high-purity germanium (HPGe) γ-ray detectors combined with a suite of ancillary detection systems and coupled to a custom digital data acquisition system. The infrastructure and detectors of the spectrometer as well as the performance characteristics and the analysis techniques applied to the experimental data are described

Water waves, fixed cylinders and floating spheres: fully nonlinear diffraction calculations compared to detailed experiments

To increase the capabilities of the computer calculations a computer code for fully nonlinear potential calculations with water waves and floating bodies had been developed earlier. It uses a boundary integral equation formulation, which is discretized to give a higher order panel method. In the current thesis this computer code has been applied to diffraction calculations of regular waves of moderate steepness incident on fixed, surface piercing cylinders with circular and rectangular cross-sections

SAR sensing of vegetation wetness:The first results

Interception of rainfall by vegetation constitutes a large fraction of total water use and an important feedback mechanism in the hydrological cycle. Research used to be restricted to in situ observations at the patch scale. We present ERS-SAR observations to scale-up local observations. Microwave backscatter increases with the amount of rain water collected on the leaves. At the canopy scale, sensitivity of SAR to vegetation wetness is still present, as well as sensitivity to wetness of the upper soil layer. ERS-SAR data recorded just before and after rainfall are being analysed. Radar backscatter increases for almost all surfaces after rainfall. Preliminary we conclude: 1) ERS-SAR is useful to estimate vegetation wetness; 2) Best results are obtained when soil wetness and reflectivity are known; 3) The satellite determination of vegetation wetness may become more accurate when a larger angle of incidence is used