Abstract
A Si(Li)-NaI(Tl) detector system is shown to be very promising for measurements of Pu in human lungs via the L x rays. The Si(Li) detectors are mounted on their edge to permit the front surface to view the lung and the back surface to view a NaI(Tl) anticoincidence scintillator for background suppression. Silicon has high intrinsic efficiency for detection of low-energy x rays and low sensitivity to background-producing gamma rays. By virtue of the high-energy resolution of the Si(Li) detectors, the UL x-ray peaks are separated from the NpL x-ray peaks thereby making it feasible to measure Pu in the presence of 241Am. The high resolution further reduces background thereby providing for high sensitivity. Measurements of Pu in lung phantoms were made with a prototype Si(Li)-NaI(Tl) detector system to simulate a pair of six-Si(Li)-detector arrays using a 2.5-cm-thick tissue-equivalent absorber. With a lung burden of 15 nCi 239Pu and 0.1% 241Am, a 2000-sec measurement gave a total UL x-ray count (UL beta and UL gamma) to square-root-of-background ratio of 2.1 which corresponds to a confidence level of 85%.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
