| We present the ab-initio method of numerical simulation of sharply-expanding nonideal plasmas. Its novel feature is a renormalization of time and introduction of the scalable coordinate frame. As a result, the effect of plasma expansion is reduced to some effective viscous forces for the charged particles performing their motion in a formally fixed spatial domain. This approach enables us to integrate the equations of motion over extremely long time intervals, without appreciable loss in the accuracy. The most interesting result of such simulations is the temperature variation in strongly expanding ultracold plasmas, which was found to follow the law t^(-1.2) instead of t^(-2), as would be expected for a free adiabatic expansion of monatomic gas [Yu.V. Dumin, Plas. Phys. Rep., v.37, p.858 (2011)]. This finding is in perfect agreement with recent experimental data on the dynamics of ultracold plasmas created in the magneto-optical traps [R.S. Fletcher, et al., Phys. Rev. Lett., v.99, p.145001 (2007)]. |
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