Alignment of Emission Gamma Ray Sources with Nai(Ti) Scintillation Detectors by Two Laser Beams to Pre-Operation using Alternating Minimization Technique
| Main Author: | Abbas Ali Mahmood Karwi |
|---|---|
| Format: | Article |
| Bahasa: | eng |
| Terbitan: |
, 2012
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/1073321 |
Daftar Isi:
- Accurate timing alignment and stability is important to maximize the true counts and minimize the random counts in positron emission tomography So signals output from detectors must be centering with the two isotopes to pre-operation and fed signals into four units of pulse-processing units, each unit can accept up to eight inputs. The dual source computed tomography consist two units on the left for 15 detector signals of Cs-137 isotope and two units on the right are for 15 detectors signals of Co-60 isotope. The gamma spectrum consisting of either single or multiple photo peaks. This allows for the use of energy discrimination electronic hardware associated with the data acquisition system to acquire photon counts data with a specific energy, even if poor energy resolution detectors are used. This also helps to avoid counting of the Compton scatter counts especially if a single discrete gamma photo peak is emitted by the source as in the case of Cs-137. In this study the polyenergetic version of the alternating minimization algorithm is applied to the dual energy gamma computed tomography problem.