Recent Activities

Fast Electron impact ionization studies of RNA base molecules

We, in recent times, have initiated an experimental investigation to study the high energy electron impact ionization of biomolecules, namely Uracil (C4H4N2O2). Towards that end we are using an effusive jet of Uracil molecule in gas phase and a crossed beam Wiley - McLaren type Time of Flight (ToF) mass spectrometer. To achieve a good mass resolution and to avoid the deflection caused by the field between Pusher and Puller plate (separated by 30 mm) we are using both pulsed electron beam and pulsed extraction field. Briefly the pulsed electron beam is obtained by pulsing the blanker electrode of the electron gun. After an adjustable period of time, during which the interaction region remains field free and the electron beam passed through the interaction region, the ion extraction is started. After the extraction the extracted ions are accelerated which is followed by a field free long drift tube. After drifting through the drift tube finally the ions are detected by a Channel Electron Multiplier. An accurate measurement of total ionization cross-section for electron impact on Uracil molecule can be measured.