Development of a Gamma-Ray Beam Profile Monitor for the High-Intensity Gamma-Ray Source
Beam profile monitors provide position and
ux distribution information to facilitate the
configuration of an experimental apparatus and are an important component of any accelerator
facilities beam diagnostic system. Nuclear physics experiments typically involve the
incidence of high energy particles or gamma-rays on some target material and the detection
of the products of the ensuing interactions. Therefore, knowing the profile of the incident
radiation beam is desirable. To address the need for a profile monitor for the High-Intensity
Gamma-Ray Source, development of a CCD-based gamma-ray beam profiler was undertaken.
The profiler consisted of plastic scintillator, a lens system and a Starlight Express MX5
CCD camera, all contained within a light tight box. The scintillation pattern, created by
the interaction between the incident gamma-rays and the scintillator, could be focused onto
the CCD. Simulations were used to determine the amount of power that would be absorbed
for different beam energies and scintillator thicknesses. The use of a converter material,
placed directly against the scintillator to improve power deposition, was also investigated.
The system was tested in order to and the camera noise characteristics, the optical resolution
and magnification and the systems responsivity to power absorption in the scintillator.
Using a 137Cs source, preliminary beam proles were obtained. By combining the results of
the testing and simulation, predictions of the required length of exposure were made. It was
determined that a beam with a flux of 10^6/s and a diameter of 2.5 cm could be profiled,
using 6.0 mm of plastic scintillator and 0.6 mm of iron converter, to within 5% error per
0.64 mm x 0.91 mm resolving unit, in less than 1 minute.
Advisor:Igarashi, Ru; Kolb, Norman R.
School:University of Saskatchewan
School Location:Canada - Saskatchewan
Source Type:Master's Thesis
Keywords:ccd beam profile monitor high intensity gamma ray source diagnostics profiling
Date of Publication:10/29/2003