Fig. 1. Flowchart of automatic spectrum stabilization flowchart

Fig. 2. Diagram of smoothing fitting effect of least squares method on energy spectrum data

Fig. 3. Schematic diagram of first-order derivative peak finding algorithm

Fig. 4. Flow chart of adaptive derivative Gaussian joint peak finding algorithm

Fig. 5. Schematic diagram of the half width and height of different nuclide characteristic peaks

Fig. 6. Experimental scene diagram of a field unmanned aerial vehicle carrying an aviation γ spectrometer

Fig. 7. Adaptive derivative Gaussian peak finding algorithm for measuring line spectrum data

Fig. 8. Fixed window width Gaussian fitting algorithm for measuring line spectrum data

Fig. 9. Derivative peak finding algorithm for measuring line spectrum data (a) Peak position changes at 0~3 min and 6~9 min, (b) Cumulative spectral lines at 0~3 min and 6~9 min