Solar flares and Kelvin-Helmholtz instabilities: particle acceleration and high energy radiation

Hard X-ray (HXR) sources are frequently observed near the top of solar flare loops, which are also bright in soft X-ray (SXR) and extreme ultraviolet (EUV) wavebands. We investigate a scenario to trigger loop-top turbulence in flaring loops, which can help explain variations seen in SXR and EUV brightenings and potentially impact and induce HXR emission. It is conjectured that evaporation flows from flare-impacted chromospheric footpoints interact with each other near the loop top and produce turbulence via the Kelvin-Helmholtz instability (KHI). This scenario suggests that the turbulence can efficiently accelerate particles and then lead to the generation of looptop HXR source via inverse Compton scattering. Here we study whether or not KHI can be triggered in the looptop by the evaporation flows and the influence of the KHI turbulence to the EUV, SXR and HXR emission.

Jaar van publicatie:2021

Toegankelijkheid:Open