A new method for removing false peaks to obtain a precise X-ray spectrum. (May 2018) - Tang, Lin
Abstract: To get a precise X-ray energy spectrum from the latest high-performance silicon drift detector (fast SDD), a switch reset preamplifier circuit, which has a high signal to noise ratio and small ballistic loss, is used to amplify the weak signal transmitted by the detector. Aiming at the technical problem of fast SDD, which works at high-count rate conditions, we adopt a slow triangle shaping method and use switch reset type preamplifier, and a new method is put forward to remove the false peaks to obtain a precise X-ray spectrum, in essence, to eliminate the distorted pulses transmitted by the detector. 55 Fe standard source and a certain kind of rock sample are regarded as measuring objects in the experiments. The spectral comparison figure, which contains the two measurement results of the pre and post elimination of the false peaks, respectively, shows that this method removes the false peaks located in the front of the full-energy peak in spectra and improves the peak-to-background ratio in a complex spectral analysis and the analytical precision of weak signals. Highlights: False peaks appear in X-ray spectra when a switch reset charge sensitive preamplifier is integrated with semiconductor detectors and the pulse shaping mode employed is slow triangular pulse shaping. A method for removing false peaks from X-ray spectra is proposed. To verify the simulation result experimentally, 55 Fe standard source and a certain kind of rock sample were used as the measuring objects.