9/20/2010 Colloquium - Dan Chivers
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Dan ChiversUniversity of California, Berkeley |
Event Info
Title: Electron-track Compton Imaging: Chasing the Holy Grail
Date: Sept 20, 2010
Location: 3105 Etcheverry Hall
Time: 4-5pm
Abstract
For the past decade, Compton imaging systems have been developed based on position-sensitive semiconductor detectors for use in Homeland Security and Nuclear Safeguards applications. The imaging of gamma-rays enables the localization of radioactive sources, an increase in detection sensitivity by distinguishing between signal and background, and to correlate the location of a source with other contextual information, providing additional means to increase the detection sensitivity. Conventional Compton imaging requires the knowledge of the positions and energies of multiple interactions resulting from a single incident gamma-ray producing a probability distribution for the incident gamma-ray trajectory. With the additional knowledge of the resulting Compton scattered electron trajectory the incident gamma-ray trajectory can be fully determined. An efficient approach as been devised using fully depleted, 650 micron thick, silicon-based charge-coupled devices (CCD) developed at Lawrence Berkeley National Laboratory (LBNL) characterized by a lateral spatial resolution of ~10-20 μm. It has been shown in by experimentally benchmarked models that these devices can produce information yielding a reduction of the incident probability distribution by approximately an order of magnitude.
