A germanium-68/gallium-68 generator is a device used to extract the positron-emitting isotope 68Ga of gallium from a source of decaying germanium-68. The parent isotope 68Ge has a half-life of 271 days and can be easily utilized for in-hospital production of generator produced 68Ga. Its decay product gallium-68 (with a half-life of only 68 minutes, inconvenient for transport) is extracted and used for certain positron emission tomography nuclear medicine diagnostic procedures, where the radioisotope’s relatively short half-life and emission of positrons for creation of 3-dimensional PET scans, are useful.
This is not actually a gamma emitter. Since it is used most commonly in PET scanning, the peak in this spectrum is corresponding to the rest energy of the electron or positron (electron-positron annihilation peak) at ~511 keV.
5 minute measurement with a High Purity Germanium (HPGe) radiation detector.