Small electron acceleration episodes in the solar corona

We study the energetics of non-thermal electrons produced in small acceleration episodes in the solar corona. We carried out an extensive survey spanning 2004-2015 and shortlisted six impulsive electron events detected at 1 au that were not associated with large solar flares (GOES soft X-ray class > C1) or with coronal mass ejections. Each of these events had weak, but detectable hard X-ray (HXR) emission near the west limb, and were associated with interplanetary type III bursts. In some respects, these events seem like weak counterparts of 'cold/tenuous' flares. The energy carried by the HXR producing electron population was similar to 10(23)-10(25) erg, while that in the corresponding population detected at 1 au was similar to 10(24)-10(25) erg. The number of electrons that escape the coronal acceleration site and reach 1 au constitute 6 per cent to 148 per cent of those that precipitate downwards to produce thick target HXR emission.