Scheduled System Maintenance:
On May 6th, system maintenance will take place from 8:00 AM - 12:00 PM ET (12:00 - 16:00 UTC). During this time, there may be intermittent impact on performance. We apologize for the inconvenience.
By Topic

Remote alpha imaging in nuclear installations: new results and prospects

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

The purchase and pricing options are temporarily unavailable. Please try again later.
6 Author(s)
Lamadie, F. ; CEA-DEN/DDCO, Bagnols Sur Ceze ; Delmas, F. ; Mahe, C. ; Girones, P.
more authors

For more than ten years the CEA has been using gamma imaging systems for radiological characterization purposes during decommissioning operations. This technology is very effective for detecting high-energy gamma emitters, but less so for characterizing actinides, which are mainly alpha emitters. In order to provide a full range of decommissioning tools, the gamma-cameras were supplemented by another imaging system capable of generating images directly from alpha emissions. This paper describes the initial laboratory and field test results obtained with a prototype camera capable of displaying alpha radioactivity. The system is based on the detection of ultraviolet radiation emitted by nitrogen when irradiated by alpha particles. The alpha contamination is localized by superimposing it on a visible-light image. All measurements must be carried out in complete darkness. Laboratory tests showed that the system is capable of detecting point sources and extended sources at levels as low as 430 Bqmiddotcm-2. Profile measurements of point sources revealed a scintillation bubble with dimensions corresponding to the range of alpha particles in air. The device is also capable of detecting the phenomenon through translucent materials such as glove box panels. The camera has been implemented for in situ examination of various fuel cycle facilities, and under these conditions has revealed alpha contamination without any breach of containment through several millimeters of plexiglas

Published in:

Nuclear Science, IEEE Transactions on  (Volume:52 ,  Issue: 6 )