Nuclear Instruments & Methods in Physics Research B vol:266 issue:19-20 pages:4652-4656
A method is presented for the detection of charged particles emitted in the b-decay of exotic nuclei. Direct implantation of radioactive nuclei in a very thin double-sided silicon strip detector is now feasible thanks to the advances in the production and post-acceleration of ISOL beams. The high degree of pixelazation, and consequently the small active volume of the detector, and the precise energy of the radioactive ion beam are the key features of the method. Among the advantages of the method are a good precision of the overall normalization and a reduction of the background due to b-radiation. Several developments are described in the present paper. The detection threshold at low energies is determined using pulsed signals. An alternative energy calibration for the decay events, free from any dead layer effects can be performed by implanting radioactive ions decaying to known narrow resonances, e.g. 20Na. Time and position correlations in a small detection volume can be used to identify possible different decay channels. An overview of precision measurements using this technique is given to prove the strength of the method.