L. V. Kostyukova | Searcharxiv

arXiv2010

Mirror instability in a plasma with cold gyrating dust particles

In this work linear stability analysis of a magnetized dusty plasma with an anisotropic dust component having transversal motions much stronger than motions parallel to the external magnetic field, and isotropic light plasma components is described. Such a situation presumably establishes in a shock compressed space dusty plasma downstream the shock front. Oblique low-frequency magneto-hydrodynamic waves ($ω\ll ω_{cd}$, $ω_{cd}$ being the dust cyclotron frequency) are shown to be undergone to the mirror instability. Consequences for nonthermal dust destruction behind shock fronts in the interstellar medium are discussed.

physics.plasm-ph↗

arXiv2010

On saturation of betatron acceleration of dust particles behind shock fronts

Possible saturation of betatron acceleration of dust particles behind strong shock fronts from supernovae is considered. It is argued that the efficiency of the nonthermal dust destruction should be substantially lower than the value estimated from a traditional description of betatron acceleration of dust grains behind radiative shock waves. The inhibition of the nonthermal destruction can be connected with the mirror instability developed in the dust component behind strong shocks with the velocity 3 times exceeding the Alfvén speed. The instability develops on characteristic time scales much shorter the age of a supernova remnant, thus its influence on the efficiency of dust destruction can be substantial: in the range of shock velocities 100 km s$^{-1}<v_s<300$ km s$^{-1}$ the destruction efficiency can be an order of magnitude lower that normally estimated.

astro-ph.GA↗