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We present a quantitative model of the magnetic energy stored and thenreleased through magnetic reconnection for a flare on 26 Feb 2004. This flare,well observed by RHESSI and TRACE, shows evidence of non-thermal electrons onlyfor a brief, early phase. Throughout the main period of energy release there isa super-hot (T>30 MK) plasma emitting thermal bremsstrahlung atop the flareloops. Our model describes the heating and compression of such a source bylocalized, transient magnetic reconnection. It is a three-dimensionalgeneralization of the Petschek model whereby Alfven-speed retraction followingreconnection drives supersonic inflows parallel to the field lines, which formshocks heating, compressing, and confining a loop-top plasma plug. Theconfining inflows provide longer life than a freely-expanding orconductively-cooling plasma of similar size and temperature. Superposition ofsuccessive transient episodes of localized reconnection across a current sheetproduces an apparently persistent, localized source of high-temperatureemission. The temperature of the source decreases smoothly on a time scaleconsistent with observations, far longer than the cooling time of a singleplug. Built from a disordered collection of small plugs, the source need nothave the coherent jet-like structure predicted by steady-state reconnectionmodels. This new model predicts temperatures and emission measure consistentwith the observations of 26 Feb 2004. Furthermore, the total energy released bythe flare is found to be roughly consistent with that predicted by the model.Only a small fraction of the energy released appears in the super-hot source atany one time, but roughly a quarter of the flare energy is thermalized by thereconnection shocks over the course of the flare. All energy is presumed toultimately appear in the lower-temperature T<20 MK, post-flare loops.

A Quantitative Model of Energy Release and Heating by Time-dependent, Localized Reconnection in a Flare with a Thermal Loop-top X-ray Source