CHANGES IN JUPITER 13-CM SYNCHROTRON RADIO-EMISSION FOLLOWING THE IMPACT OF COMET SHOEMAKER-LEVY-9

Results of an observing program to monitor the synchrotron radio emiss ion from Jupiter's inner radiation belts before, during and after the impact of Comet SL-9 are reported. The observations were made at 2295 Mhz as part of the NASA-JPL Jupiter Patrol, a long-term radio astronom y monitoring program begun in 1971. The data indicate that the intensi ty of the synchrotron emission at 13 cm wavelength increased by 27 per cent within a few days after the comet impacts; the longitudinal beami ng curve Was distorted during the week of impacts; the magnetic latitu de beaming curves flattened after the week of impacts suggesting an in crease in the emission at higher magnetic latitudes; and the decay of the enhanced emission is consistent with an exponential with a time co nstant of similar to 125 days. The reported changes following the SL-9 impact are unprecedented in the 23-year history of the Jupiter Patrol .