Experiments with a 4π charged-particle detector and the 8π spectrometer

Experimental techniques for charged-particle detectors used with 4π γ-ray spectrometers are reviewed. As examples, recent experiments at the TASCC facility in Chalk River with a 4π steradians modular miniature array of CsI(Tl) crystals coupled to large-area photodiodes operating with the "8π" spectrometer, are briefly discussed. We point out the importance of charged-particle detection in channel selection for in-beam spectroscopic studies. The main emphasis of the initial experiments with this apparatus has been on a study of the charged particles associated with superdeformed bands, and on the search for nuclear-structure effects in the evaporation spectra. Charged-particle evaporation spectra tagged with γ-ray multiplicity, total γ-ray energy and nuclear-spin orientation have been measured for events selected by gates on discrete γ-ray transitions in the residues. This detector is also being used in the search for superdeformation and hyperdeformation.