Characterization study of the CsI (T1) detector array

Abstract

The ISAC Charged Particle Spectroscopy Station (IRIS) at TRIUMF, Vancouver, Canada uses CsI(Tl)—a 16 component detector array composed of thallium-doped cesium iodide—for high resolution study of nuclear reactions. Each CsI(Tl) detector was characterized by studying its response and determining its Q-value resolution for scattering reactions. The elastic scattering of p([superscript 18]O, p)[superscript 18]O among similar higherenergy inelastic reactions were examined during the calibration process. Data from several experimental runs were compared to kinematics curves to calibrate the energy response of each CsI(Tl) sector. Elastic and inelastic Q-value peaks were corrected for dependence on scattering angle and measured for resolution. CsI(Tl) is an inorganic scintillator crystal, which is coupled to a photodiode. The annular-type detector array consists of 16 identically designed sectors. Each sector was characterized separately in order to describe the detector array as a whole. In general, the characterized CsI(Tl) detector will detect hydrogen isotope reaction products that were scattered from a target of similar atomic structure. Motivation for this study includes the future use of the CsI(Tl) detector in nuclear reactions involving radioactive ion beams at IRIS. These reactions can provide further understanding of the nuclear force, shell structure and general theory of unstable exotic nuclei.