On the nature of superdeep penetration of shock-accelerated particles into a solid target

A possible relationship between the hot prominence transition sheath, increased internal turbulent and/or helical motion prior to prominence eruption and the prominence eruption (“disparition brusque”) is discussed. The associated darkening of the filament or brightening of the prominence is interpreted as a change in the prominence’s internal pressure gradient which, if of the correct sign, can lead to short wavelength turbulent convection within the prominence. Associated with such a pressure gradient change may be the alteration of the current density gradient within the prominence. Such a change in the current density gradient may also be due to the relative motion of the neighbouring plages thereby increasing the magnetic shear within the prominence, i.e., steepening the current density gradient. Depending on the magnitude of the current density gradient, i.e., magnetic shear, disruption of the prominence can occur by either a long wavelength ideal MHD helical (“kink”) convective instability and/or a long wavelength resistive helical (“kink”) convective instability (tearing mode). The long wavelength ideal MHD helical instability will lead to helical rotation and thus unwinding due to diamagnetic effects and plasma ejections due to convection. The long wavelength resistive helical instability will lead to both unwinding and plasma ejections, but also to accelerated plasma flow, long wavelength magnetic field filamentation, accelerated particles and long wavelength heating internal to the prominence.

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APPLICATION OF THE LASER SIMULATION METHOD OF CRATER CREATION IN THE LASER-AL SOLID TARGET EXPERIMENT ON THE PALS FACILITY

High Temperature Material Processes An International Quarterly of High-Technology Plasma Processes ◽

10.1615/hightempmatproc.v7.i3.50 ◽

2003 ◽

Vol 7 (3) ◽

pp. 319-326 ◽

Cited By ~ 1

Author(s):

T. Pisarczyk ◽

S. Borodziuk ◽

A. Kasperczuk ◽

K. Jungwirth ◽

B. Kralikova ◽

...

Keyword(s):

Simulation Method ◽

Solid Target ◽

Laser Simulation ◽

Target Experiment

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Enhanced X-ray emission arising from laser-plasma confinement by a strong transverse magnetic field

Scientific Reports ◽

10.1038/s41598-021-87651-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Evgeny D. Filippov ◽

Sergey S. Makarov ◽

Konstantin F. Burdonov ◽

Weipeng Yao ◽

Guilhem Revet ◽

...

Keyword(s):

Magnetic Field ◽

Transverse Magnetic ◽

Radiative Properties ◽

Magnetic Field Direction ◽

Solid Target ◽

Total Plasma ◽

Plasma Confinement ◽

X Ray ◽

Magnetic Compression ◽

The Magnetic Field

AbstractWe analyze, using experiments and 3D MHD numerical simulations, the dynamic and radiative properties of a plasma ablated by a laser (1 ns, 10$$^{12}$$ 12 –10$$^{13}$$ 13 W/cm$$^2$$ 2 ) from a solid target as it expands into a homogeneous, strong magnetic field (up to 30 T) that is transverse to its main expansion axis. We find that as early as 2 ns after the start of the expansion, the plasma becomes constrained by the magnetic field. As the magnetic field strength is increased, more plasma is confined close to the target and is heated by magnetic compression. We also observe that after $$\sim 8$$ ∼ 8 ns, the plasma is being overall shaped in a slab, with the plasma being compressed perpendicularly to the magnetic field, and being extended along the magnetic field direction. This dense slab rapidly expands into vacuum; however, it contains only $$\sim 2\%$$ ∼ 2 % of the total plasma. As a result of the higher density and increased heating of the plasma confined against the laser-irradiated solid target, there is a net enhancement of the total X-ray emissivity induced by the magnetization.

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