<p> In nuclear astrophysics, there are still undiscovered areas involving unstable nuclei, like the nucleosynthesis in exploding stars. The unstable nuclei are extremely difficult to produce in the laboratory for study since they decay away quickly once they are formed. To make the unstable nuclei available in the laboratory, Canada has built one of the best facilities in the world for nuclear astrophysics studies with radioactive beams, called TRIUMF-ISAC. Its recent upgrade to ISAC-2 can produce even heavier radioactive beams with higher energy. To fully utilize the ISAC-2 facility, a high-segmented HPGe γ-ray detector-TIGRESS, has been
developed to study exotic nuclei using the well-established technique of Coulomb Excitation.</p> <p> As an essential part of the TIGRESS facility, auxiliary detectors, such as silicon
detectors, are used to improve the sensitivity of the experiments through Doppler correction. Two types of silicon detectors will be used. One is the CD-shaped double-sided silicon strip detector, which is the topic of this thesis. The other one is the silicon barrel detector. This thesis will discuss the computer simulations and experimental tests of the CD detector.</p> <p> Simulations were made using a simulation toolkit GEANT4, which was run under the Linux system. The goal was to test the hypothesis that measurements of the energies of heavy ions in Coulomb excitation may improve the Doppler correction by constraining the scattering location in a thick target. To test the performance of the simulated CD detector, simple simulations were performed for shooting calibration alpha particles from an 241Am source first directly onto the CD and second through a thin target onto the CD. The goal of additional simulations was to attempt to determine the corresponding scattering depth in a thick target by putting an energy cut on the spectrum of the scattered beam detected in the
CD. These simulation results verify the possibility of such localization, though the resolution is not very good.</p> <p> Experimental tests for the CD detector are aimed to obtain the energy resolution for each strip element of the CD and to have at least 8 channels instrumented in our test lab before this detector is sent to TIGRESS facility. The test station
including electronics and detector systems and all results from initial tests are described in detail in this thesis.</p> / Thesis / Master of Science (MSc)
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/21581 |
| Date | 02 1900 |
| Creators | Chen, Jun |
| Contributors | Chen, Alan, Physics and Astronomy |
| Source Sets | McMaster University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
Page generated in 0.0024 seconds