- Physics & Astronomy
- 02.01.2017 3:30 pm - 4:30 pm
Title: Thick Gas Electron Multiplier: an Attractive Gaseous Radiation Detector for Imaging and Dosimetry
Speaker: Dr. Soo Hyun Byun
Institute: McMaster University
Location: ABB 102
In order to address the fundamental physics problems encountered in radiation detection and dosimetry, my research group has focused on advanced gaseous radiation detector and signal processing system developments. A gaseous detector is one of the popular radiation detection methods and there has been outstanding progress in its technology in the last decade. Since 2008, my group has been developing THick Gas Electron Multiplier (THGEM) detectors which offer unique features in contrast to traditional gaseous proportional counters. In this talk, I will briefly review the underlying physics on THGEM and present our THGEM detectors geared for imaging and dosimetry. Owing to its fast signal rise time, the THGEM neutron imaging detector is a good candidate for very high count rate experiments encountered in modern neutron scattering experiments in spallation neutron sources, nondestructive assay of nuclear materials, etc.
For any kind of radiation detectors, the importance of signal processing can never be overemphasized. With the recent progress in digital electronics, detector signal processing has been dramatically improved over the classical analog processing. I will present our recent signal processing systems that have been developed for a variety of radiation detectors.
The last topic of my talk will be low level gamma-ray spectrometry for 60Co and 26Al, radionuclides of interests for meteorites. A common challenge we face in low level radioactivity analysis is that the counts from a sample are buried under background radiation counts. For the multi-photon emitters like 60Co and 26Al, this challenge can be overcome by operating detectors in coincidence mode, in which case a large fraction of the background counts can be rejected while most cascade gamma-ray counts from a sample are saved. I will present our recent Monte Carlo simulation study for optimizing the coincidence geometry and development of the McMaster 4p digital NaI(Tl) spectrometer.