Harmonics of Solar Radio Spikes at Metric Wavelengths

Abstract

This paper presents the latest observations from the newly-built solar radio spectrograph at the \emph{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.

arXiv comment17 pages,6 figures

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Cited by in corpus (4)

• Extreme solar events
• Mapping the magnetic field in the solar corona through magnetoseismology
• Harmonic elctron-cyclotron maser emissions driven by energetic electrons of the horseshoe distribution with application to solar radio spikes
• Harmonic maser emissions from electrons with loss-cone distribution in solar active regions