Energy Release from Impacting Prominence Material Following the 2011June 7 Eruption

Solar filaments exhibit a range of eruptive-like dynamic activity, ranging from the full or partial eruption of the filament mass and surrounding magnetic structure as a coronal mass ejection (CME), to a fully confined dynamic evolution or failed eruption. On 2011 June 7, a dramatic partial eruption of a filament was observed by multiple instruments on SDO and STEREO. One of the interesting aspects of this partial eruption is the response of the solar atmosphere as non-escaping material falls inward under the influence of gravity. The impact sites show clear evidence of brightening in the observed EUV wavelengths due to energy release. Two plausible physical mechanisms explaining the brightening are considered: heating of the plasma due to the kinetic energy of impacting material compressing the plasma, or reconnection between the magnetic field of the low-lying loops and the field carried by the impacting material. By analyzing the emission of the brightenings in several SDO/AIA wavelengths, and comparing the kinetic energy of the impacting material (7.6×10^26 - 5.8×10^27 ergs) to the radiative energy (2×10^25 - 2×10^26 ergs) we find the dominant mechanism of energy release involved in the observed brightening is plasma compression.