Analysis on TypeⅡ Burst and Solar Activity

In this paper we analyse the correlations among solar meterwave type Ⅱ bursts, SID events, Hα flares and X-ray recored form Jan. 1987 to Dec. 1994. The result is that SID closely asso ciated with meterwave typeⅡ burst sand 86% of the SID occured before typeⅡ bursts. This may indicate that SID events are caused by solar UV and X-ray radiation while slow drift type Ⅱ burst sare related with MHD shock waves produced by flares. When the shock waves transfer from the corona, electrons in front of the MHD shock wave excite plasma to radiate and then cause the type Ⅱ bursts.