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The analysis of the stability properties of astrophysical jets against Kelvin-Helmholtz (or shear-layer) instabilities plays a basic role in the understanding the origin and physical characteristics of these objects. Numerical simulations by Bodo et al. (1998) have shown that the three-dimensional non-linear evolution of KH instabilities in supersonic jets is substantially faster than in the two-dimensional case, leading to a cascade of modes towards smaller scales and a very effective mixing and momentum transfer to the ambient medium. On the other hand, Rossi et al. (1997) and Micono et al. (1998) found, in two dimensions, that radiative losses tend to reduce and delay mixing effects and momentum transfer to the ambient medium. In this paper, as a logical next step, we investigate the effects of radiative losses on the stability of 3D supersonic jets, assuming that the internal jet density is initially lower, equal and higher than the ambient medium, respectively. We find that light and equal-density radiative jets evolve in a qualitatively similar fashion with respect to the corresponding adiabatic ones. Conversely, we note substantial differences in the evolution of heavy jets: they remain more collimated and do not spread out, while the momentum gained by the ambient medium stays within ~ 5 jet radii.
Using data obtained by the high resolution CRisp Imaging SpectroPolarimeter instrument on the Swedish 1-m Solar Telescope, we investigate the dynamics and stability of quiet-Sun chromospheric jets observed at disk center. Small-scale features, such a
We have investigated magnetic field generation in velocity shears via the kinetic Kelvin-Helmholtz instability (kKHI) using a relativistic plasma jet core and stationary plasma sheath. Our three-dimensional particle-in-cell simulations consider plasm
Observations show various jets in the solar atmosphere with significant rotational motions, which may undergo instabilities leading to heat ambient plasma. We study the Kelvin-Helmholtz (KH) instability of twisted and rotating jets caused by the velo
The Kelvin-Helmholtz instability serves as a simple, well-defined setup for assessing the accuracy of different numerical methods for solving the equations of hydrodynamics. We use it to extend our previous analysis of the convergence and the numeric
The Kelvin-Helmholtz (KH) instability is studied in a non-Newtonian dusty plasma with an experimentally verified model [Phys. Rev. Lett. {bf 98}, 145003 (2007)] of shear flow rate dependent viscosity. The shear flow profile used here is a parabolic t