A Search for Transient Events at 843 MHz

Abstract 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 ± 1.5 MHz) with time scales between 0.001 ms and 800 ms. The multiple beam facility of the telescope provides some discrimination against local interference. An upper limit of 1.7 × 10 −2 events s −1 sr −1 has been placed on celestial events with durations between 1 ms and 25 ms and energy density ≥ 10 −28 J m −2 Hz −1 . The monitoring system has been recently reconfigured to improve the recognition and rejection of impulsive signals of non-celestial origin.