Example of Imaging gamma-ray spectroscopy (Extreme low background Spectroscopy)

Background Gammas (BG) from outward PSF are easily rejected. By imaging rejection, BG is reduced by a factor of 10^-2~3.

• Example spectroscopy of weak RI source.
• ²²Na (27 kBq, 511 keV) with a distance of 5.5 m.
• 8×10^-5 μSv/h at the front of ETCC (1/1000 of Environmental radiation).