Speaker
Prof.
João Veloso
(University of Aveiro)
Description
Compton Cameras are being pointed as the instrument for far X and gamma-ray detection where the traditional Anger Cameras are inefficient. Moreover, these devices avoid the use of a heavy mechanical collimator responsible for a huge decrease of the photons that reach the Anger Camera crystal [1], [2].
Traditionally a Compton Camera is composed of solid state detectors (Si detector + Ge or NaI detector)[3]. Our proposal is to use a single High Pressure Scintillation Counter for the Compton and scattered photon interactions, based on Bolozdynya setup [4], by changing the high cost and low position resolution PMT array by a low cost gaseous photomultiplier with energy resolution and position discrimination capability: THCOBRA [5].
In this work we present the initial characterization of the high pressure gas scintillation proportional counter (HpGSPC) for pure Xenon pressures ranging from 1- to 5 atm. The optical gain and energy resolution as function of the drift and scintillation fields where studied by using a PMT achieving energy resolutions below 4% for 59.6 keV photons.
Calculation of the number of primary electrons and intrinsic position resolution will be presented as function of the gas pressure.
A detailed discussion of the experimental measurements and a comparison with simulation results is performed.
Results and details on the coupling of a gaseous photomultiplier based on a THCOBRA and operating in Ne/CH4 will be presented.
[1] N. A. Pavel, Nucl. Inst. Meth. A, 478, 1–12, 2002
[2] A. Del Guerra et al., Nucl. Inst. Meth. A, 583, 119–124, 2007.
[3] W. G. Phillips, Nucl. Inst. Meth. B, 99,674–677, 1995.
[4] A. Bolozdynya et al., Nucl. Inst. Meth. A, 385,. 225–238, 1997.
[5] C. D. R. Azevedo et al., Nucl. Inst. Meth. A, 732, 3–6, 2013. Assoc. Equip., vol. 732, pp. 3–6, 2013.
Primary author
Dr
C. D. R. Azevedo
(I3N – Department of Physics, University of Aveiro, Portugal)
Co-authors
Ms
Beatriz Silva
(I3N – Department of Physics, University of Aveiro, Portugal)
Mr
Fábio Pereira
(University of Aveiro)
Dr
J. F. C. A. Veloso
(I3N – Department of Physics, University of Aveiro, Portugal)
Mr
P. M. M. Correia
(I3N – Department of Physics, University of Aveiro, Portugal)