Type III burst pair

We present a special solar radio burst detected on 5 January 1994 using the multi-channel (50) spectrometer (1.0-2.0 GHz) of the Beijing Astronomical Observatory (BAO). Sadly, the whole event could not be recorded since it ha d a broader bandwidth than the limit range of the instrument. The important part was obtained, however. The event is composed of a normal drift type I II burst on the lower frequency side and a reverse drift type III burst app earing almost simultaneously on the high side. We call the burst type III a burst pair. It is a typical characteristic of two type III bursts that the y are morphologically symmetric about some frequency from 1.64 GHz to 1.78 GHz on the dynamic spectra records, which indicates that there are two diff erent electron beams from the same acceleration region travelling simultane ously in opposite directions (upward and downward). A magnetic reconnection mode is a nice interpretation of type III burst pair since the plasma beta beta similar or equal to 0.01 is much less than 1 and the beams have veloc ity of about 1.07 x 10(8) cm s(-1) after leaving the reconnection region if we assume that the ambient magnetic field strength is about 100 G.