Tischcenko V.N.   Zakharov Y.P.   Berezutskiy A.   Boyarintsev E.   Melekhov A.V.   Posukh V.G.   Shaikhislamov I.F.   Miroshnichenko I.B.  

Momentum and angular momentum of laser plasma produced by irradiation of the target is in a magnetic field in a vacuum.

Reporter: Berezutskiy A.

In the experiment [1] a new effect was revealed: periodic laser plasma bunches create in the magnetic field in vacuum unbroken stream of rotating plasma propagating in a narrow power tube of the external field. The length of the flow depends linearly on the number of bunches, and the radius of the energy of one bunch. The stream has the properties of torsional Alfven and slow magnetosonic waves. The effect is of interest for the transport of momentum and angular momentum in a magnetic field in a highly rarefied medium. As follows from calculations on clusters, the azimuthal rotation speed of the plasma most critically depends on the parameters of bunches and magnetic field.
At the KI-1 facility of the ILP SB RAS, were conducted experiments in which the formation of a stream with the maximum rotation speed of the plasma around its axis. Plasma bunches (2H++C3+) were created by successive irradiation of polyethylene target (Q ~ 200 J) by a train located in a vacuum chamber with a magnetic field B0 is 100 – 500 G. The plasma concentration, temperature, velocity, longitudinal current, and the components of the magnetic and electric fields were measured. When fulfilling the criteria for the manifestation of the mechanism of merging of wave, plasma bunch was successively filled a force tube whose diameter is approximately equal to the dynamic radius Rd of one bunch. At a distance the order of 5 Rd, the velocity of the leading edge of the stream decreases from a maximum value of the order of 150 km/s to a velocity of 80 to 90 km / s, which depends weakly on the external magnetic field? The maximum speed of plasma rotation in the flow is 40 km / s achieved when the conditions for the effective formation of the torsion Alfvén wave in the magnetoplasma tube are satisfied: the ratio of the Larmor radius to Rd is ~ 1, the ratio of the Larmor radius to the ion-inertial length is more than ~5.
1.V. N. Tishchenko, Yu. P. Zakharov, I.F. Shaikhislamov, A. G. Berezutskiy, E. L. Boyarintsev, A. V. Melekhov, A. G. Ponomarenko, V. G. Posukh, P. A. Prokopov. JETP Letters, 2016, Volume 104, Issue 5, pp 293–296.

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