Posted on 6 April 2018
Both workshops collaborated on the machine between March 2017 and March 2018. The initial design called for a simple manual X, Y, Z movement of a detector bed within a basic enclosure. The design continually changed and evolved into a highly complex, precision computer controlled research instrument that could not be purchased “off the shelf”.
John Emery, Jason Flatt, Wayne Robinson and Brent Wilkinson from both the Electronics and Mechanical workshops used their depth of specialised knowledge and experience in their respective fields to not only design the vast majority of the project, but also constructed the entire build.
John Emery (Electronics Specialist) explained, "this is one of the largest projects I have worked on in my career to date in terms of complexity, duration and scale. At times it was hard to see the project coming to an end, especially when specifications changed mid-build but the commitment and encouragement from the Mechanical Workshop team gave me the extra motivation I needed to continue. It makes me extremely proud to see what we have achieved, from developing a rough sketch of an idea to producing a fully functional bespoke piece of experimental equipment, which will help further research in the department. I feel working on this project has brought both the Mechanical and Electronics workshops closer as a team, and allowed both workshops to demonstrate their skills. Working on this project has also helped strengthen existing bonds between our workshops and other workshops on campus including Biology and Electronic Engineering".
This instrument is now fully installed and is already being used by researchers within the group.
The scanning platform employs an intense, 662 keV gamma-ray beam emanating from a 1 mm circular collimator, housed in the top of the machine. Radiation detectors are mounted on a bed which moves in the z axis, additionally a pair of computer controlled linear stages allow movement of the detectors in the x-y plane. This allows a beam of gamma photons to impinge upon radiation detectors at specific, well defined locations and the detector response to be characterised as a function of interaction position.
Panaj Joshi and Jamie Brown from the Nuclear Group said, "the intense beam of gamma rays allows precision scanning of radiation detectors much faster than with a conventional bench-top solution thereby accelerating this research".
The principal application of this research is in homeland security to meet challenges such as pinpointing the location of a radiation source. In addition there are various medical and pure physics applications where finding the directionality of gamma rays is desirable.