抄録
Multi-fragment momentum imaging methods in which the momentum images of all kinds of fragment
ions can be captured simultaneously, are developed for controlling chemical reactions through ultrafast
charge migration processes of polyatomic molecules, including amino acids or bio-relevant molecules.
In the momentum imaging method developed in this study, the temporal information of the fragment
ions is recovered using time-intensity or time-polarization tagging methods, where the polarization of
fluorescence emitted from the phosphor is temporally modulated by an electro-optic light modulator.
This realizes one-to-one correspondence between the time-of-flight of fragment ions and the polarization
direction of fluorescence. In addition, an ion momentum imaging apparatus with multi-fragment momentum
imaging is integrated with a sample injection system of non-volatile molecules through laser-induced
acoustic desorption. The operation modes can be easily switched from the velocity map imaging
to spatial map imaging to measure the spatial-resolved mass spectrum in a single-shot.
