INTERPRETATION OF THE OBSERVED CHANGES IN JUPITERS SYNCHROTRON-RADIATION DURING AND AFTER THE IMPACTS FROM COMET SHOEMAKER-LEVY-9

The effects of the Shoemaker-Levy 9 collision with Jupiter included an abrupt and impulsive disturbance to Jupiter's inner magnetosphere. A substantial change to the radio emission originating from Jupiter's ra diation belts (synchrotron radiation) was reported and confirmed by nu merous observers. The major effect on the radiation belts is due to th e latitude of the impact sites on Jupiter. The impacts occurred at the footprint of the magnetic field lines connecting Jupiter's inner radi ation belts with the planet. Interferometric maps suggest changes may have continued for weeks after the impacts. The reported increases in synthrotron emission indicate substantial changes to the high energy e lectron population trapped in Jupiter's radiation belts. A number of m echanisms were suggested almost immediately to explain the observed ch anges: (1) enhanced radial diffusion, (3) shock acceleration and energ ization of the electron population and (3) pitch angle scattering of t he emitting electrons from plasma waves triggered by the comet impacts . A review of the interpretation of the radio data and a discussion of the consistency between the proposed mechanisms and the observations is presented. A complete understanding of the state of the radiation b elts before, during and after the impacts has not yet been reached and requires extensive modeling. (C) 1997 Published by Elsevier Science L td. All rights reserved.