A HIGH FREQUENCY TYPE II SOLAR RADIO BURST ASSOCIATED WITH THE 2011 FEBRUARY 13 CORONAL MASS EJECTION

We examine the relationship between a type II radio burst that started from an unusually high frequency of 425 MHz (fundamental component) and an associated white-light coronal mass ejection on 2011 February 13. The radio burst had a drift rate of 2.5 MHz/sec, indicating a relatively high shock speed. From SDO AIA observations we find that a loop-like erupting front sweeps across high density coronal loops near the start time of the burst (17:34:15 UT). We find fragmented structures of the type II burst, which indicates the signature of the shock propagating through the multiple loops. The deduced distance of shock formation (0.06 Rs) from flare center and speed of the shock (1100 km $s^{-1}$) using the measured density from AIA/SDO observations are comparable to the height (0.05 Rs, from the solar surface) and speed (700 km $s^{-1}$) of the CME leading edge observed by STEREO/EUVI. We conclude that the type II burst could be onset even in the low corona (41 Mm or 0.06 Rs, above the solar surface) if a fast CME shock passes through the high density loops.