First results with the Microball and Gammasphere

The Microball, an improved 4{pi} multi-detector array, was used recently in conjunction with Gammasphere in three experiments. Highlights of the first results are presented here. The Microball consists of 95 CsI(T{ell}) scintillation detectors with individual Si photodiode readout, arranged in 9 rings. In these first experiments the Microball performed as designed, but the results in new physics exceeded the authors` expectations. They can say with certainty that by its powerful channel selection the Microball enhanced the performance of Gammasphere by one full coincidence fold. This was possible for all exit channels involving charged particle emission, with increasing performance benefit as one progressed to lighter reaction systems. They summarize the essential characteristics of the Microball and give some performance benchmarks. A detailed description of the Microball is given