Particle Detectors: (4.1) (1) Gamma-Ray Tracking: Correlating and constructing the multiple interactions of a single γ-ray in a segmented detector is the main technique of γ-ray tracking. The new generation of 4Π Ge detectors has been developed to significantly improve the efficiency and resolving power of γ-ray spectroscopy. The tracks of the γ-rays in the Ge-detector can be constructed in 3D. A detector used for this purpose consists of: (a) High-fold segmented Ge detectors. (b) Digital signal processing electronics. (c) Pulse-Shape analysis algorithms for real time applications