Patent attributes
A mass spectrometer and method for performing high resolution mass spectrometry are provided, the mass spectrometer comprising an electrostatic trap and mass analyzer. The electrostatic trap comprises entrance and exit ends, entrance and exit end ion mirrors, a central field-free region, and a longitudinal axis. The mass analyzer receives ions from the exit end. Ions are admitted into the electrostatic trap via the entrance end, trapping ions in the electrostatic trap, the ions oscillating between the entrance and exit end ion mirrors along the axis. The electrostatic trap waits for the ions to separate into bunches different m/z values via the oscillating, and then excites a given bunch of ions of a given m/z value along the axis until at least a portion of the given bunch overcomes a barrier field at the exit end ion mirror, exiting the electrostatic trap for analysis, leaving behind remaining ions.