An approach for improving signal-to-noise ratio in photoelectron velocity map imaging experiments

Background irradiated electrons in photoelectron spectra are known to take place under the ultraviolet light irradiation. Therefore, it deserves discussing the reduction of such electrons in the electron spectra in this work. The main problem present in these electron spectra will largely be overcome through a workflow and process, namely, a combination method of rotating images with angular-tailored and subtracting noise electrons of images which gives rise to non-noise electron peaks. An improved SNR is readily obtained for REMPI-SEVI spectra of 3-bromofluorobenzene (3-Br-FPh) compared with no noise-subtracted and no-angular-tailored spectra. More details are given including electron velocity-map imaging analysis on S−, CuOH−(H2O), and 3-Br-FPh in the following sections.