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arXiv · 2506.06819

A Novel Fine Spectral Structure of Solar Radio Bursts with Periodic Beaded Stripes Observed by CBSm of CMP-II

Chuanyang Li·Yao Chen·Bing Wang·Ze Zhong·Baolin Tan·Zongjun Ning·Hao Ning·Xiangliang Kong·Shuwang Chang·Yanke Tang·Ning Gai·Li Deng·Jingye Yan·Fabao Yan
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Abstract

A novel fine spectral structure in solar radio bursts has been discovered using the Chashan broadband solar radio spectrometer at meter wavelengths (CBSm), an instrument of the Chinese Meridian Project-Phase II (CMP-II). The structure features periodic narrow-band stripes with a typical recurrence time $< 1 $ s (occasionally reaches 8 s), often drifting from high to low frequencies and accompanied by absorptions, with trailing stripes appearing at the end of preceding ones. Some stripes exhibit periodic beaded enhancements with a periodicity of $\sim$0.1 s. The beaded stripes are reported for the first time ever. Data from the DAocheng Radio Telescope (DART) indicate a radio emission brightness temperature exceeding $10^{9}$ K, originating above brightening loops in active region AR 13664. We proposed a novel generation mechanism of the periodic stripes on the basis of the double plasma resonance (DPR) instability, and explained the beaded substructure in terms of modulation by low-frequency magnetohydrodynamic (MHD) waves. The study highlights the CBSm's capability to detect high-resolution fine spectral structures and offers novel insights into the emission mechanism and source characteristics of solar radio bursts.

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Chuanyang Li, Yao Chen, Bing Wang, Ze Zhong, Baolin Tan, Zongjun Ning, Hao Ning, Xiangliang Kong, Shuwang Chang, Yanke Tang, Ning Gai, Li Deng, Jingye Yan, Fabao Yan. 2025-06-07. A Novel Fine Spectral Structure of Solar Radio Bursts with Periodic Beaded Stripes Observed by CBSm of CMP-II. https://arxiv.org/abs/2506.06819

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