A search for transient events at 843 MHZ

The Molonglo Observatory Synthesis Telescope is equipped with a transient event monitoring system which operates during normal synthesis observations. The device is designed to respond to impulsive signals which occur within the passband (843.0 + or - 1.5 MHz) with time scales between 0.001 msec and 800 msec. The multiple beam facility of the telescope provides some discrimination against local interference. An upper limit of 0.017 events/sec sr has been placed on celestial events with duration between 1 and 25 msec and energy density of not less than 10 to the -28th J/sq m Hz. The monitoring system has been recently reconfigured to improve the recognition and rejection of impulsive signals of noncelestial origin.