Resolution Optimization by Trace Fitting a Charged Particle Detector Telescope

An experiment to study neutron-unbound states of ¹³Be required detection of charged particles, neutrons, and gamma rays in a high effiency arrangement due to possible decay to a long-lived isomeric state in ¹²Be. The experiment was performed at the National Superconducting Cyclotron Laboratory on the campus of Michigan State University. Charged particles were identified using a detector telescope system consisting of one silicon position sensitive detector (140 μm thick) and a stack of five silicon detectors (500 μm thick) with a CsI(Tl) crystal (3 cm thick) read out by a silicon pin diode. Neutrons passed through the detectors with minimal attenuation to be detected by the MoNA-LISA neutron detector array, and gamma rays from the decay of the implanted ¹²Be were detected in a gamma-detector array surrounding the charged-particle telescope. A digital data acquisition system was used to process the charged particle detector signals for which the offline analysis utilized trace fitting procedures to identify charged fragments and improve resolution. This talk will discuss in detail the trace fitting procedures and data reduction process.