Performance Evaluation of Component Detectors of Double-scattering Compton Camera
Seo, Hee;Park, Jin-Hyung;Kim, Chan-Hyeong;Lee, Ju-Hahn;Lee, Chun-Sik;Lee, Jae-Sung;
ABSTRACT
Prototype double-scattering Compton camera, which consists of three gamma-ray detectors, that is, two double-sided silicon strip detectors (DSSDs) as scatterer detectors and a NaI(Tl) scintillation detector as an absorber detector, could provide high imaging resolution with a compact system. In the present study, the energy resolution and the timing resolution of component detectors were measured, and the parameters affecting the energy resolution of the DSSD were examined in terms of equivalent noise charge (ENC). The energy resolutions of the DSSD-1 and DSSD-2 were, in average, $25.2keV{pm}0.8keV$ FWHM and $31.8keV{pm}4.6keV$ FWHM at the 59.5 keV peak of $^{241}Am$, respectively. The timing resolutions of the DSSD and NaI(Tl) scintillation detector were 57.25 ns FWHM and 7.98 ns FWHM, respectively. In addition, the Compton image was obtained for a point-like $^{137}Cs$ gamma source with double-scattering Compton camera. From the present experiment, the imaging resolution of 8.4 mm FWHM (angular resolution of $8.1^{circ}$ FWHM), and the imaging sensitivity of $1.5{times}10^{-7}$ (intrinsic efficiency of $1.9{times}10^{-6}$) were obtained.