标题：Harmonics of Solar Radio Spikes at Metric Wavelengths
作者：Feng, S. W.; Chen, Y.; Li, C. Y.; Wang, B.; Wu, Z.; Kong, X. L.; Du, Q. F.; Zhang, J. R.; Zhao, G. Q.
作者机构：[Feng, S. W.; Chen, Y.; Li, C. Y.; Wang, B.; Wu, Z.; Kong, X. L.; Du, Q. F.; Zhang, J. R.] Shandong Univ, Shandong Prov Key Lab Opt Astron & Solar Ter 更多
通讯作者：Feng, SW;Feng, SW;Feng, SW
通讯作者地址：[Feng, SW]Shandong Univ, Shandong Prov Key Lab Opt Astron & Solar Terr Env, Weihai 264209, Peoples R China;[Feng, SW]Shandong Univ, Inst Space Sci, We 更多
关键词：Radio burst; Dynamic spectrum; Radio spike; Electron cyclotron maser; emission
摘要：This paper presents the latest observations from the newly built solar radio spectrograph at the Chashan Solar Observatory. On July 18, 2016, the spectrograph records a solar spike burst event, which has several episodes showing harmonic structures, with the second, third, and fourth harmonics. The lower harmonic radio spike emissions are observed later than the higher harmonic bands, and the temporal delay of the second (third) harmonic relative to the fourth harmonic is about 30 - 40 (10) ms. Based on the electron cyclotron maser emission mechanism, we analyze possible causes of the temporal delay and further infer relevant coronal parameters, such as the magnetic field strength and the electron density at the radio source.