The dielectronic recombination is one of the most important atomic processes in highly ionised plasmas. It corresponds to the simultaneous capture of a free electron and excitation of an ion, i.e.
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It is a collisionally resonant process which occurs only at the energy of the corresponding autoionisation electron. We present here a preliminary theoretical analysis of the results of an experiment using a novel technique in which it is possible to observe the interaction of a given ion with an electron at a given energy and so to measure the differential dielectronic cross section corresponding to each resonant level of this ion.