Development Of Detector System For Direct Reaction Of Weakly Bound Nuclei

Some of experiments have been performed for the elastic scattering of the weakly bound nuclei,such as ⁶He,¹¹Be and ¹¹Li,at energies around the Coulomb barriers.However,the experimental data for the energies above the Coulomb barriers are very scarce.A typical experimental phenomenon of the elastic scattering for the neutron-rich nuclei is that the Coulomb rainbow peak is partially or completely suppressed.It has been suggested that this phenomenon is caused by both nuclear and Coulomb breakup couplings.However,this phenomenon didn't exist in the experiment of the elastic scattering of ⁸B at energy of 3.3 times of the Coulomb barriers.The dependence of coupled-channel with the valence nucleon or the incident energies has not been confirmed.This is one of research topics of group.A detector system consists of four sets of telescopes has been developed and applied in the experiment of the elastic scattering of Nitrogen-12 and Oxygen-13 induced by Radioactive Ion Beams?RIBs?on the Radioactive Ion Beam Line in Lanzhou?RIBLL?at the Heavy-Ion Research Facility in Lanzhou?HIRFL?.Based on this work,we plan to develop a new telescopes system.The detector will be used to measure the angular distributions of both elastic scattering and breakup channel simultaneous.And also,it is the main research content of this thesis.The detector system consists of five telescopes in three different sizes,which are used to identify recoiling light charged particles through energy loss and energy measurements.Each telescope consists of one double-sided silicon strip detector?DSSD?thickness in 150 ?m,and one single silicon detector?SSD?of 1500 ?m in thickness.The DSSDs were used to measure the energy loss and the position of the particles passing through the detector.The SSDs were used to measure the remaining energy.All of telescopes covering forward angles are placed on a stainless steel supporting structure that was designed by Solid Works.The detector device consists of 448 individual silicon strips and 5 silicon detectors whose signals must be amplified and digitalized.Each DSSD is associated with its own pre-amplifier board closely located at the supporting structure in order to improve signal-to-noise ratio.All of detectors and pre-amplifiers have been assembled completely and tested using alpha sources.Energy spectra have been acquired and the energy resolution is better than 1%.