Long-transit-time multipactoring at ultra-high frequencies, and the effect of surface emitting layers

An account is given of multipactor discharges occurring at 400 Mc/s in which electron transit times were much longer than the field period, and an analysis is developed, accounting reasonably well for the observed variations of discharge voltage with pressure. Evidence is obtained of the formation of emitting layers during these discharges, but it is shown that these do not appreciably affect the steady-state conditions.