Radio and X-ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare

Solar flares release enormous magnetic energy into the corona, resulting in plasma heating and acceleration of particles. The flaring process is complex and often shows multiple individual particle acceleration episodes, which can be hard to resolve based on the instrument capability. We present multi-wavelength imaging and spectroscopy observations of multiple electron acceleration episodes during a GOES B1.7-class two-ribbon flare observed simultaneously with the Karl G. Jansky Very Large Array (VLA) at 1--2 GHz, the Reuven Ramatay High Energy Solar Spectroscopic Imager (RHESSI) in X-rays, and the Solar Dynamics Observatory in extreme ultraviolet (EUV). A total of six radio bursts were observed in short succession. The first three bursts were co-temporal, but not co-spatial with a nonthermal X-ray source and represented multiple electron acceleration episodes. Their radio spectra were modelled by optically thick gyrosynchrotron emission, and estimates of the magnetic field strength and nonthermal electron spectral parameters in each acceleration episode were derived. We find that the nonthermal parameters derived from X-rays differ considerably from the nonthermal parameters inferred from the radio observations. We interpret the observations as multiple acceleration episodes that resulted in different electron populations propagating in separate magnetic loops.