Fourier denoising analysis in Bρ-defined isochronous mass spectrometry

By installing two time-of-flight detectors on the straight section of the storage ring to measure the orbital time and velocity of stored ions, high-precision quality measurement can be achieved. The electromagnetic noise of the detection system is one of the main sources of uncertainty in the quality value of B ρ - IMS.

In the development process of B ρ - IMS, digital Fourier denoising analysis was applied to process the full waveform timing signal sampled by a digital oscilloscope. In the analysis, multiple periodic electrical components were unexpectedly discovered in the timing signal, with frequencies that are exactly integer multiples of the oscilloscope sampling rate. Through this analysis, for nuclides with atomic numbers Z ≥ 15, the systematic bias in the re determined mass values is eliminated at the 1 σ confidence level; At the same time, the accuracy of the measured velocity and ion mass has also been improved to the same extent, with an increase of 7% to 20%.