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We present an X-ray imaging and spectroscopic study of a partially occultedC7.7 flare on 2003 April 24 observed by RHESSI that accompanied a prominenceeruption observed by TRACE. (1) The activation and rise of the prominenceoccurs during the preheating phase of the flare. The initial X-ray emissionappears as a single coronal source at one leg of the prominence and it thensplits into a double source. Such a source splitting happens three times, eachcoinciding with an increased X-ray flux and plasma temperature, suggestive offast reconnection in a localized current sheet and an enhanced energy releaserate. In the late stage of this phase, the prominence displays a helicalstructure. These observations are consistent with the tether-cutting and/orkink instability model for triggering solar eruptions. (2) The eruption of theprominence takes place during the flare impulsive phase. Since then, thereappear signatures predicted by the classical CSHKP model of two-ribbon flaresoccurring in a vertical current sheet trailing an eruption. These signaturesinclude an EUV cusp and current-sheet-like feature (or ridge) above it. Thereis also X-ray emission along the EUV ridge both below and above the cusp, whichin both regions appears closer to the cusp at higher energies in the thermalregime. This trend is reversed in the nonthermal regime. (3) Spectral analysisindicates thermal X-rays from all sources throughout the flare, while duringthe impulsive phase there is additional nonthermal emission which primarilycomes from the coronal source below the cusp. This source also has a lowertemperature, a higher emission measure, and a much harder nonthermal spectrumthan the upper sources.

Episodic X-ray Emission Accompanying the Activation of an Eruptive Prominence: Evidence of Episodic Magnetic Reconnection