What energy level is associated with Gallium-68 (Ga-68)?

Gallium-68 is a positron-emitting radionuclide commonly used in PET imaging. When Gallium-68 undergoes positron emission, it decays into stable Zinc-68, releasing positrons. These positrons interact with electrons in the surrounding matter, resulting in the annihilation of the two particles. This annihilation process produces gamma photons, each carrying an energy of 511 keV, a characteristic of the annihilation radiation. The two 511 keV photons are emitted in nearly opposite directions and are crucial for the detection and imaging processes in positron emission tomography (PET).

Understanding the significance of the 511 keV energy level is essential for both interpreting PET scans and for ensuring proper settings and calibration for gamma detectors in nuclear medicine practice. The other energy levels listed do not correspond to the characteristic emissions from the decay of Gallium-68.