The details of the interaction of Jupiter and its satellite Io have been subject to interest of theoretical and experimental research for many years. It is well known that the orbital motion of Io leads to the excitation of disturbances, travelling along the Jovian magnetic field towards the planet, and exciting some specific phenomena in the Jovian system such as non thermal radio emissions and aurora on Jupiter. In spite of the previous work in this subject explaining the energy transfer, which mainly concerns Alfvénic waves, we apply another approach based on MHD slow mode waves. These slow mode waves are generated by a pressure pulse in the vicinity of Io and propagate along the converging Jovian magnetic field accompanied by a supersonic flow. Due to decreasing cross section and the increasing magnetic field the bulk velocity of this plasma flow is enhanced. Such plasma flows lead to the generation of an electric potential difference, which accelerates precipitating electrons as they pick up the potential drops energy when they fall through the potential. Such electron distribution are a crucial ingredient for the explanation of some magnetospheric phenomena. The main point is that the slow mode waves are much slower than the Alfvénic waves and can provide an explanation for the lag between some parts of the Jovian decameter emission and the Io flux tube which can be observed in experimental observations.
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