ИСТИНА

It is well known already from the first experiments with ultracold plasmas that cold electrons experience a violent relaxation of their velocities, leading to the sharp increase in the electron temperature, which exceeds by an order of magnitude the value expected from the virial relation. Here, we test the hypothesis that such anomalous heating is caused by the ionic clusters, which serve as the regions of multi-electron interactions and their subsequent acceleration. As follows from our numerical simulations, the above-mentioned clusterization really result in: (1) a much greater initial jump in the electron temperature on the timescale about the inverse Langmuir frequency and (2) a considerable subsequent heating on a longer timescale, which is presumably caused by the three- (or multi-)body recombination.