TRAVERSAL OF COMET SL-9 THROUGH THE JOVIAN MAGNETOSPHERE AND IMPACT WITH JUPITER - RADIO UPPER LIMITS

Continuous radio observations below 1 MHz of Jupiter from the Ulysses spacecraft are used to establish an upper limit to the radiated power at low frequencies associated with the traversal through the magnetosphere and impact of Comet SL-9 with the planet. Although Jovian emissions were observed throughout the impact interval, no systematic intensity changes were observed before, during, or after the fragment impact times as a whole. Examined individually, a large intensity increase, probably associated with a solar wind compression at Jupiter, was observed at the time of the P impact. Intense solar type III bursts, which can sometimes be confused with Jovian emissions, occurred often, which serves as a caution to other (groundbased) radio observers. We derive an upper limit for the interfragment dust density of 10(-3)/m(3) in the context of a dust-magnetosphere interaction model proposed earlier.