Patent ID: 8158934

Claim:
An electron capture dissociation apparatus, comprising: a first axial end; a second axial end disposed at a distance from the first axial end along a central axis; a plurality of ion guide electrodes arranged along the central axis from the first axial end to the second axial end, the ion guide electrodes spaced circumferentially from each other about the central axis and disposed at a radial distance in a transverse plane orthogonal to the central axis, wherein the ion guide electrodes circumscribe an ion guide interior space extending along the central axis from the first axial end to the second axial end; an electron emitter disposed outside the ion guide interior space; and an electron control device configured for focusing an electron beam from the electron emitter toward the central axis, along a radial electron beam direction between two of the ion guide electrodes and axially between the first axial end and the second axial end, and for decelerating the electron beam in a DC decelerating field of adjustable voltage potential directed along the electron beam direction.