A multianode microchannelhyphen;plate (MCP) detector was operated in a transverse magnetic field. When a collimated ion beam of sim;4 mm diameter impinged on one area of the plate, ghost images were observed elsewhere on the plate at anodes up to several centimeters from the beam spot. This effect is due to secondary electrons which are emitted from the interstitial surfaces around the MCP pores and returned to the surface of the plate under the influence ofEtimes;Bfields, whereEis the electric field perpendicular to the plate due to the MCP bias potential andBis the externally applied transverse magnetic field. A regenerative process is observed in which the secondary electrons traverse the surface of the plate in theEtimes;Bdirection by successive gyrohyphen;orbit steps. A method for suppressing the ghost images is discussed.
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