We present a quantitative model of the magnetic energy stored and then released through magnetic reconnection for a flare on 26 February 2004. This flare, well observed by RHESSI and TRACE, shows evidence of non-thermal electrons for only a brief, early phase. Throughout the main period of energy release there is a super-hot (T 30 MK) plasma emitting thermal bremsstrahlung atop the flare loops. Our model describes the heating and compression of such a source by localized, transient magnetic reconnection. It is a threedimensional generalization of the Petschek model, whereby Alfvén-speed retraction following reconnection drives supersonic inflows parallel to the field lines, which form shocks: heating, compressing, and confining a loop-top plasma plug. The confining inflows provide longer life than a freely expanding or conductively cooling plasma of similar size and temperature. Superposition of successive transient episodes of localized reconnection across a current sheet produces an apparently persistent, localized source of high-temperature emission. The temperature of the source decreases smoothly on a time scale consistent with observations, far longer than the cooling time of a single plug. Built from a disordered collection of small plugs, the source need not have the coherent jet-like structure predicted by steady-state reconnection models. This new model predicts temperatures and emission measure consistent with the observations of 26 February 2004. Furthermore, the total energy released by the 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 at any one time, but roughly a quarter of the flare energy is thermalized by the reconnection shocks over the course of the flare. All energy is presumed to ultimately appear in the lower-temperature (T 20 MK) post-flare loops. The number, size, and early appearance of these loops in

We report the results of a statistical study of the relationship between eruptive solar flares and an observed H preflare phenomenon we call moving blueshift events (MBSEs). The H data were gathered using the Mees Solar Observatory CCD imaging spectrograph (MCCD). The 16 events in our data set were observed by both the MCCD and the Yohkoh Soft X-Ray Telescope, typically for at least 3 hr prior to the flare and in some cases repeatedly for several days prior to the flare. The data set contains both eruptive and noneruptive flares, without bias. Focusing on 3 hr periods before and after the flares, we found that the average rate of MBSEs prior to the flares was $5 times greater prior to the 11 eruptive flares than prior to the five noneruptive ones. Also, the average rate of MBSEs dropped by a factor of $6 after the eruptive flares. Earlier studies inferred that MBSEs reflect motions that originate in the readjustment of magnetic fields after magnetic reconnection. From the high correlation between eruptive flares and preflare MBSEs in the several hours prior to such events, we conclude that reconnection in the chromosphere or low corona plays an important role in establishing the conditions that lead to solar flare eruptions.

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