A new instrument of broadband solar radio spectrometer working at waveband 4.5-7.5 GHz was developed at Purple Mountain Observatory for Solar Maximum 23. Some n
Radio observational results at 232 MHz and multifrequency studies of the supernova remnant (SNR) HB21 are presented. Its integrated flux density at 232 MHz is a
A quantitative method to determine the lower energy cutoff (Ec) ofpower-law electron beams is established. We apply this method to the 54 hardX-ray events obse