A new detector for mass spectrometry: Direct detection of low energy ions using a multi-pixel photon counter

A new type of ion detector for mass spectrometry and general detection of low energy ions is presented. The detector consists of a scintillator optically coupled to a single-photon avalanche photodiode (SPAD) array. A prototype sensor has been constructed from a LYSO (Lu1.8Y0.2SiO5(Ce)) scintillator crystal coupled to a commercial SPAD array detector. As proof of concept, the detector is used to record the time-of-flight mass spectra of butanone and carbon disulphide, and the dependence of detection sensitivity on the ion kinetic energy is characterised. (C) 2012 American Institute of Physics. [doi:10.1063/1.3676164]