Summary form only given. The properties of a plasma generatedbetween the pulses (interpulse plasma) of high power (60-100 kW), shortpulse (0.05-1.0 μs) microwaves of 3 GHz are studied in a range ofpλ=10-1=102 Torr-cm, where p is thepressure and λ is the wavelength. Argon plasma is produced insidea cylindrical vessel with a characteristic diffusion length ~3 cm, andconfined by a multicusp magnetic field. Interpulse plasmas havedemonstrated unique properties1-3 as compared toconventionally known afterglows. Some novel features include a delayedplasma build up which prolongs even after the end of the microwave pulseand a high electron temperature which persists even in the power offphase of the discharge. In this report, we present further results withfocus on the characteristics of the build up over a wide pressure range.The peak value of the currents and the total optical intensity includingtheir respective build up times show a minimum around 1 Torr. The pulserepetition frequency (10-500 Hz) has a negligible effect on the peakcurrents, build up time, growth and decay constants. Increase in pulseduration, however, has a finite influence on the discharge; the peakcurrent and growth constant increases and the build up time decreases.The experimental observations are discussed in the light of theoreticalconsiderations
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