Letter to the Editor

An intriguing solar microflare observed with RHESSI, Hinode, and TRACE

¹ Space Sciences Laboratory, University of California at Berkeley, Berkeley, CA, 94720-7450, USA e-mail: hannah@ssl.berkeley.edu
² Physics Department, University of California at Berkeley, Berkeley, CA, 94720-7450, USA

Received: 8 November 2007
Accepted: 3 December 2007

Abstract

Aims.We investigate particle acceleration and heating in a solar microflare.

Methods.In a microflare with non-thermal emission to remarkably high energies (>50 keV), we investigate the hard X-rays with RHESSI imaging and spectroscopy and the resulting thermal emission seen in soft X-rays with Hinode/XRT and in EUV with TRACE.

Results.The non-thermal footpoints observed with RHESSI spatially and temporally match bright footpoint emission in soft X-rays and EUV. There is the possibility that the non-thermal spectrum extends down to 4 keV. The hard X-ray burst clearly does not follow the expected Neupert effect, with the time integrated hard X-rays not matching the soft X-ray time profile. So, although this is a simple microflare with good X-ray observation coverage it does not fit the standard flare model.