Direct Observation Of High-speed Plasma Outflows Produced By Magnetic ReconnectionIn Solar Impulsive Events

Spectroscopic observations of a solar limb flare recorded by SUMER on SOHO reveal, for the first time, hot fast magnetic reconnection outflows in the corona. The Observations from TRACE and RHESSI allow us to determine the location of magnetic reconnection region. We find that as the reconnection site rises across the SUMER spectrometer slit, significant blue- and red-shift signatures are observed in the Fe XIX line, reflecting upflows and downflows of hot plasma jets, respectively. With the projection effect corrected, the measured outflow speed is between about 900-3500 km/s, consistent with thoeretic predictions. Based on theoretic models, the magnetic field strength near the reconnection region is estimated to be 19-37 Gauss. Our observations of reconnection jets and other signatures such as the erupting flux loop and cusp-shaped postflare loops are consistent with the classic scenario of magnetic reconnection of solar flares.