Solar radio radiation bursts on 1998 April 15

We present two remarkable "decimetric pulsation" events (DCIM) around the t ime 1998 0415 0800, detected by spectrometers (1.00-2.00 GHz and 2.60-3.80 GHz) at Beijing Astronomical Observatory (BAO). High-resolution dynamic spe ctra reveal various fine structures, such as spike groups, pulsations, type -III bursts, patches, and zebra patterns or evolving emission lines on the rising phase of the second DCIM around 3 GHz. It is the first time that suc h a wealth of fine features have been detected in a same type IV-DCIM event ; it is also the first time that blips pairs simultaneously drifting toward s the same frequency have been recorded; it is the second time to observe a n evolving emission line, and the first above 1 GHz.