The limiting mode of the generation of low-frequency torsional whistlers is obtained for the first time. Laser plasma clouds create only weak whistlers in a weakly magnetized laboratory plasma (argon), allowing the whistler magnetic field to reach record values of ~25% of the background magnetic field.

On the base of NASA [1] new approach about important role of Giant plasma releases of so called Coronal Mass Ejections (CME, with kinetic energy up to Ei 10363pr) from the Sun, we have started a series of simulative experiments [2, 3] with Laser -produced Plasma (LP), expanding into magnetized Background Plasma (BP) to generate laboratory Quasi -Perpendicular collisionless Shocks (Q -PS) by LP -piston for the first time. As a result of such experimental scenario, with the I,P-model of CME and Q -PS as interplanetary Collisionless Shock Wave (CSW, observed ahead of super-Alfvenic CME), we did a first comparative study of a quasi -stationary model of magnetosphere (by BP, overflowing magnetic dipole 1.1.) with its compressed form after LP formation and following Q -PS generation in BP. During the first set [3] of such experiment MagnetoPause-Shock (MPS), we had measured a maximal additional (due to Q -PS) compression near twice of the total (and global quasi uniform) magnetic field Bi inside of MP. Here we could present and discuss some specific experimental features of these ft -fields and both their models and distributions. Additional attention was done to the important collisionless processes of the Q -PS generation, especially in the given case of the different mass (m/z) of ions in LP -piston. For the last purpose a new data on the dynamics of such ions (H"and C'n) were presented including data of 2D and 3D calculations by Hybrid models with PIC (Particles In Cells) description of all ions.

We report the results for the first complex experiment on the formation of an extended (up to similar to 0.5 m) plasma jet in a magnetic field (up to 300G) in vacuum. The jet appears due to the injection of laser plasma bunches with a kinetic energy up to similar to 50 J across the magnetic field (in a solid angle Omega approximate to 1 sr) and a high degree of magnetisation of ions on the calculated scale field-induced deceleration of the bunch as a part of a sphere. A plastic target (polyethylene) has been irradiated by a CO2 laser in the most energy-efficient regime (near the plasma formation threshold), implemented at the expense of a wide radiation spot (diameter 23 cm) on the target. In a new-type model Super-Jet experiment on a large KI-1 facility at the Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences (ILP SB RAS), the probe data on the internal structure and dynamics of plasma concentration and magnetic field strength in transverse jets, on the influence of instabilities and Hall effect have been obtained for the first time in laboratory modelling of space and astrophysical jets.

Abstract It was shown for the first time that in a laboratory experiment a train of laser plasma clouds makes it possible to increase the length of the whistler waves generated in the power tube of a magnetized medium. The intensity of waves is orders of magnitude higher than the level achieved by known methods.

Whistler waves produced by periodic bunches of a laser plasma in a magnetized plasma are investigated. It is shown for the first time that a train of laser plasma bunches generates a packet of torsional whistlers, which contains a high-frequency front part and a quasi-stationary track localized in a power tube. The length of the track increases with the number of bunches, which allows you to control the spectrum of the waves and form low-frequency waves.

Plasma flows produced by periodic bunches of a laser plasma in a magnetic power tube are investigated. The transfer is possible by a single stream of a rotating compressed plasma or three successively propagating streams: a rotating stream of background plasma, a plasma flow of bunches and a compressed background plasma that carries a longitudinal momentum. With a low concentration of the background plasma, the velocity of the longitudinal momentum is supersonic.

Hot Jupiters (HJ) are exoplanets, gas giants with low orbits (≤ 0.1 a.u.). The stellar X-ray and ultraviolet (XUV) radiation energy deposition result in heating ionization and the consequent expansion of planetary atmosphere. Expansion of upper atmosphere under certain conditions could be so large that the majority of light atmospheric constituents overcome the gravitational binding and escape from the planet in a form of hydrodynamic wind. Besides interaction of two counter-streaming plasma flows (stellar wind and ionized upper layers of planet atmosphere), each of this flows interact with planetary magnetic field. In such complex situation laboratory simulation can provide data that can’t be obtained by computer simulation or observation. Experiment was carried out on KI-1 facility: high-vacuum chamber 5m long, 1.2 m in diameter with pressure ∼ 10-6 Torr. Magnetic dipole with two attached laser targets played the role of a planet, and background plasma from θ-pinch used for simulation of stellar wind. As a result, data on a behavior of plasma density and magnetic field were obtained. The novel phenomenon was registered: magnetic field is transferred by the cloud of laser plasma, which was not observed before in experiments or calculations.

Dynamic interaction of super-sonic counter-streaming plasmas moving in dipole magnetic dipole is studied in laboratory experiment. First, a quasi-stationary flow is produced by plasma gun which forms a magnetosphere around the magnetic dipole. Second, explosive plasma expanding from inner dipole region outward is launch by laser beams focused at the surface of the dipole cover. Laser plasma is energetic enough to disrupt magnetic field and to sweep through the background plasma for large distances. Probe measurements showed that far from the initially formed magnetosphere laser plasma carries within itself a magnetic field of the same direction but order of magnitude larger in value than the vacuum dipole field at considered distances. Because no compression of magnetic field at the front of laser plasma was observed, the realized interaction is different from previous experiments and theoretical models of laser plasma expansion into uniform magnetized background. It was deduced based on the obtained data that laser plasma while expanding through inner magnetosphere picks up a magnetized shell formed by background plasma and carries it for large distances beyond previously existing magnetosphere.

Giant plasma releases of so called Coronal Mass Ejections (CME, with kinetic energy up to Ek ∼ 1036 эрг) from the surface of the Sun and their potential catastrophical impact onto Earth’s magnetosphere, with the probable opportunity to compress it in 2, 3 or more times [1, 2], represent one of the most important problem in the geophysical and historical bio-evolutional investigations of the past and present of the Earth. It was supposed that the re-connection of dipole magnetic field at magnetopause could play [2] an exclusive role in its inward shift, but from the more general point of view (to perform laboratory simulation [3-6] of magnetopause dynamics), a more important and common features of CME propagation in Solar Wind plasma are the formation of collisionless Quasi-Perpendicular Shocks (Q-PS) ahead of Super-Alfvenic CME. It is provided by the almost radial (along to R) motion of CME from the Sun, while the Interplanetary Magnetic Field B0 has an angle θ ∼ 45° (relative to R) near the Earth orbit. Up to date, in spite of intensive development of laser energetics and energy of Laser-produced Plasma (LP), such Q-PS never were generated by LP [7], excluding recent experiment [8] at KI-1 facility of ILP. In the given work, a first results of our study were presented together with relevant calculations by hybrid code and the basic physics of VNIIEF-model [9] for the collisionless Magnetic Laminar Mechanism (MLM) of interaction between a spherical LP and magnetized Background Plasma (BP). A special analysis was done on the conditions and data of the formation of whistler precursor in front of revealed oblique (Q-PS) shocks as well as on the first data of dipole's field compression by BP and Shocks.

In laboratory experiments using laser plasma, the criteria are confirmed in which periodic plasma bunches form simultaneously two types of quasi-stationary waves: torsional Alfven and slow magnetosonic waves propagating along the magnetic field tube.

In experiments, the momentum and angular momentum of the slow magnetosonic and torsional Alfven waves produced by irradiating train of laser pulses of the target in a magnetic field in a vacuum or in a rarefied plasma with a magnetic field were investigated. At "resonance" of plasma bunches with background, a single Alfven wave and a single slow magnetosonic wave are formed. These waves transfer a momentum in a narrow tube of the magnetic field, angular momentum variation of the current, and the electric field.

Problem of the global and even catastrophic modification of the Earth's magnetosphere (into Artificial one) by impulsive and huge plasma ejecta, was proposed for the first time during our study of possible after-effects of high-energy explosions against asteroids at near-Earth space. Later, a similar problem of extreme compression of the Earth's magnetopause from its usual Rmp ≈ 10RE up to new stand-off distance Rm* ∼ 3RE, by plasma of giant Coronal Mass Ejections (CME, with effective energy E0 ∼1028 J), was considered for its simulations by Laser-Produced Plasma (LPP) at KI-1 facility of ILP, that were done initially without “Solar Wind” (in AMEX experiment). Here we present the first results of the “full” laboratory simulations of the CME-problem with the up-stream impact of LPP (with E0 ∼ 1 kJ) onto classical terrella-model of “stationary” magnetopause (with Rmp ≈ 17 cm), formed near compact dipole in a flow of background H+-plasma, imitated Solar Wind. As a result, we have observed for the first time a two-fold compression of magnetopause size, accompanied by very strong and near expected value of dipole magnetic field's compression up to the factor 7÷8 ≈ (Rmp/Rm*)3 inside of magnetopause. Our data allow to predict a global CME-effect at E0∼1029J.

The transient interaction of counter-streaming super-sonic plasma flows in a dipole magnetic dipole is studied in a laboratory experiment. First quasi-stationary flow is produced by theta-pinch and forms a magnetosphere around the magnetic dipole, while laser beams focused at the surface of the dipole cover launch a second explosive plasma expanding outward from the inner dipole region. The laser plasma is energetic enough to disrupt the magnetic field and to sweep through the background plasma for large distances. Probe measurements showed that far from the initially formed magnetosphere laser plasma carries within itself a magnetic field of the same direction but an order of magnitude larger than the vacuum dipole field at considered distances. Because no compression of the magnetic field at the front of the laser plasma was observed, the realised interaction is different from previous experiments and theoretical models of laser plasma expansion into a uniform magnetized background. It was deduced based on the obtained data that, while expanding through the inner magnetosphere, laser plasma picks up a magnetised shell formed by background plasma and carries it for large distances beyond the previously existing magnetosphere.

We present the results of first experiments on the formation of collisionless shock waves (CSWs) in background plasma by injecting laser plasma bunches transverse to the magnetic field (as a piston) with a maximum energy up to 100 J per unit of solid angle and with a high enough degree of ion magnetisation. With this aim in view, on a unique KI-1 facility at the Institute of Laser Physics, Siberian Branch of the Russian Academy of Sciences (ILP), a plastic (polyethylene) target irradiated by a CO2 laser in the most energy-efficient regime (near the plasma formation threshold) and a highly ionised hydrogen plasma with a high concentration in a large volume (not less than 1 m(3)) have been employed. As a result of model experiments performed on the basis of a model of collisionless interaction of plasma flows, developed at the VNIIEF and being adequate to the problem under consideration, not only an intensive, background-induced, deceleration of a super-Alfven laser plasma flow, but also the formation in that flow of a strong perturbation having the properties of a subcritical CSW and propagating transverse to the magnetic field, have been first registered in the laboratory conditions.

The paper deals with generation of Alfvén plasma disturbances in magnetic flux tubes through exploding laser plasma in magnetized background plasma. Processes with similar effect of excitation of torsion-type waves seem to provide energy transfer from the solar photosphere to the corona. The studies were carried out at experimental stand KI-1 representing a high-vacuum chamber 1.2 m in diameter, 5 m in length, external magnetic field up to 500 G along the chamber axis, and up to 2·10–6 Torr pressure in operating mode. Laser plasma was produced when focusing the CO2 laser pulse on a flat polyethylene target, and then the laser plasma propagated in θ-pinch background hydrogen (or helium) plasma. As a result, the magnetic flux tube 15–20 cm in radius was experimentally simulated along the chamber axis and the external magnetic field direction. Also, the plasma density distribution in the tube was measured. Alfvén wave propagation along the magnetic field was registered from disturbance of the magnetic field transverse component Bφ and field-aligned current Jz. The disturbances propagate at a near-Alfvén velocity 70–90 km/s and they are of left-hand circular polarization of the transverse component of magnetic field. Presumably, the Alfvén wave is generated by the magnetic laminar mechanism of collisionless interaction between laser plasma cloud and background. A right-hand polarized high-frequency whistler predictor was registered which propagated before the Alfvén wave at a velocity of 300 km/s. The polarization direction changed with the Alfvén wave coming. Features of a slow magnetosonic wave as a sudden change in background plasma concentration along with simultaneous displacement of the external magnetic field were found. The disturbance propagates at ~20–30 km/s velocity, which is close to that of ion sound at low plasma beta value. From preliminary estimates, the disturbance transfers about 10 % of the original energy of laser plasma.

A new effect has been experimentally revealed: a sequence of flashes of a two-component laser plasma creates a flow containing torsional Alfvén and slow magnetoacoustic waves in a magnetic flux tube.

Generation of Alfven waves propagating along external magnetic field B-0 and Collisionless Shock Waves propagating across B-0 are studied in experiments with laserproduced plasma and magnetized background plasma. The collisionless interaction of interpenetrating plasma flows takes place through a so-called Magnetic Laminar Mechanism (MLM) or Larmor Coupling. At the edge of diamagnetic cavity LP-ions produce induction electric field E-phi, which accelerates BP-ions while LP-ions rotate in opposite direction. The ions movement generates sheared azimuthal magnetic field B-phi which could launches torsional Alfven wave. In previous experiments at KI-1 large scale facility a generation of strong perturbations propagating across B-0 with magnetosonic speed has been studied at a moderate value of interaction parameter delta similar to 0.3. In the present work we report on experiments at conditions of delta similar to 1 divided by 2 and large Alfven-Mach number M-A similar to 10 in which strong transverse perturbations traveling at a scale of similar to 1 m in background plasma at a density of similar to 3*10(13) cm(-3) is observed. At the same conditions but smaller M-A similar to 2 a generation, the structure and dynamic of Alfven wave with wavelength similar to 0.5 m propagating along fields B-0 similar to 100 divided by 500 G for a distance of similar to 2.5 m is studied.

A magnetosphere comparable in size to ion inertial length, known as a mini-magnetosphere, possesses unusual features which have been predicted by numerical simulations and shown in recent experiments. In the present paper we study a pronounced difference between the west and east flanks of a mini-magnetosphere observed for the first time in pioneering terrella experiments of 60 s duration. It manifests itself in plasma penetration deep inside the west flank and the formation of a return current that effects the magnetic structure, in contrast to the east flank which has a well-defined boundary layer and plasma cavity. We propose that the plasma penetration and the return current can be understood in the framework of a test-particle model. This model serves to illustrate in simple terms the Hall physics which was found to be behind similar features at the frontal part and the tail of the mini-magnetosphere observed in our previous experiments. Because of the large gyroradius, ions tend to be deflected by the dipole field at the east flank and drawn into the west flank. To verify that the return electric current in the magnetospheric plasma is carried by ions, we measured it directly using a Rogovski coil and compared it with the ion flux measured by Langmuir probe.

An experiment on the interaction between an expanding super-Alfvénic laser-produced plasma flow and a magnetized background plasma under conditions in which the ion gyroradius is comparable with the characteristic scale length of magnetic field displacement is described. The depletion of the background plasma in a substantial volume and the formation of a large-amplitude compression pulse propagating with a super-Alfvénic velocity are revealed. The efficiency of energy conversion into perturbations of the background plasma was found to be 25%. Combined data from magnetic, electric, and plasma measurements indicate that the interaction occurs via the magnetic laminar mechanism.