On measurement of energy transfer from exploding plasma to magnetic field

Summary form only given. A method is proposed to measure the absolute amount of exploding plasma energy that goes into the magnetic energy gain in over-all space including the wave zone at the deceleration stage of plasma expansion into an external vacuum uniform magnetic field. It is based on measuring local field disturbances apart from a plasma cloud so they are defined rather by induced dipole magnetic moment than by multipoles of next orders. One can determine the "interaction energy" E/sub I/ corresponding to the total magnetic energy gain by use of a single remote 2- or 3-component magnetic probe\´s signal. The state function E/sub 1/ owes its origin to the expansion work but the latter as a process function exactly equals to E/sub I/ only under isothermic conditions as with "superconducting sphere" model. Generally E/sub I/ may present a main part of losses in the initial kinetic energy E/sub 0/ of an exploding plasma that goes also into the plasma\´s heat due to diffusion processes as well as into movement of polarized plasma jets rising from flute instabilities. In experiments with laser-produced plasma clouds the measurement of the ratio E/sub I//E/sub 0/ is needed to find the real efficiency of the "plasma-field" interaction (E/sub 0/ is measured for example by means of Langmuir electric probes).