Multiple focus formation in a Mather gun device

Along with the normally produced pulses of dI/dt, x-ray, optical emission, neutrons and ions by a Mather type plasma focus gun, one more set of pulses were observed to be generated by a low energy device at Trombay, a few 100 ns after the first set of pulses, in majority of the discharges. In a small number of discharges even three or more sets of pulses were observed. Signals from pick-up probes placed in the run down region of the device suggest formation of more than one sheath which subsequently may form more than one focus which in turn is responsible for the second and subsequent sets of pulses.