Multimass Velocity-Map Imaging with the Pixel Imaging Mass Spectrometry (PImMS) Sensor: An Ultra-Fast Event-Triggered Camera for Particle Imaging

We present the first multimass velocity-map imaging data acquired using a new ultrafast camera designed for time-resolved particle imaging. The PImMS (Pixel Imaging Mass Spectrometry) sensor allows particle events to be imaged with time resolution as high as 25 ns over data acquisition times of more than 100 μs. In photofragment imaging studies, this allows velocity-map images to be acquired for multiple fragment masses on each time-of-flight cycle. We describe the sensor architecture and present bench-testing data and multimass velocity-map images for photofragments formed in the UV photolysis of two test molecules: Br₂ and <i>N</i>,<i>N</i>-dimethylformamide