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M Pekker

Publications and source records attributed to M Pekker.

4 recordsLinked to original sources

Angular momenta creation in relativistic electron-positron plasma.

Creation of angular momentum in a relativistic electron-positron plasma is explored. It is shown that a chain of angular momentum carrying vortices is a robust asymptotic state sustained by the generalized nonlinear Schrödinger equation characteristic to the system. The results may suggest a possible electromagnetic origin of angular momenta when it is applied to the MeV epoch of the early Universe.

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Dynamics of self-trapped singular beams in an underdense plasma.

Dynamics of an intense short laser pulse with a phase singularity, propagating in an underdense cold plasma, is investigated. Such a pulse can propagate as a vortex soliton in a self-created channel. It is shown that vortices with the topological charge m=1,2 (and a corresponding angular momentum) are unstable against symmetry-breaking perturbations; the breakup of the original vortex leads to the formation of stable spatial solitons that steadily fly away tangentially from the initial ring of vortex distribution.

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Decompressive (cooling rarefaction) shock in optically thin radiative plasma.

It is shown that the decompressive shock, i.e., a shock where the pressure behind the front is smaller than the pressure ahead of it, is possible in a radiative plasma; this is in contrast to the situation in classic gas dynamics. An example of a steady state decompressive shock wave for a simple, but realistic model for radiative losses is presented. It is shown that it satisfies the Landau stability criteria.

Journal Article↗