Clusters of small eruptive flares produced by magnetic reconnection in the sun

TL;DR

This study uses 3D MHD simulations to show how magnetic reconnection in the sun's atmosphere produces small, short-lived flares that contribute to plasma heating and jet formation.

Contribution

It demonstrates the spontaneous formation of small solar flares through patchy magnetic reconnection in a realistic 3D MHD model.

Findings

Small flares are 1-2 Mm in size and last 30 seconds to 3 minutes.

Flares release energies between 10^25 and 10^27 ergs.

Recurrent jets and plasma heating are driven by these small flares.

Abstract

We report on the formation of small solar flares produced by patchy magnetic reconnection between interacting magnetic loops. A three-dimensional (3D) magnetohydrodynamic (MHD) numerical experiment was performed, where a uniform magnetic flux sheet was injected into a fully developed convective layer. The gradual emergence of the field into the solar atmosphere results in a network of magnetic loops, which interact dynamically forming current layers at their interfaces. The formation and ejection of plasmoids out of the current layers leads to patchy reconnection and the spontaneous formation of several small (size ? 1-2Mm) flares. We find that these flares are short-lived (30 s - 3 min) bursts of energy in the range O(10^25 - 10^27) ergs, which is basically the nanoflare-microflare range. Their persistent formation and co-operative action and evolution leads to recurrent emission of fast EUV/X-ray jets and considerable plasma heating in the active corona.