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arXiv · 2604.26783

Coronal Diagnostics Via Modelling Periodic-Beaded Stripes of Solar Radio Bursts

Chuanyang Li·Yao Chen·Bing Wang·Yutong Li·Xiangliang Kong·Hao Ning·Sulan Ni·Shuwang Chang·Zichuan Li·Yang Gao·Zhe Cui·Li Deng·Jingye Yan·Fabao Yan
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Abstract

Using high-resolution data from the Chashan Broadband Solar radio spectrometer at meter wavelengths (CBSm) of the Chinese Meridian Project-Phase II (CMP-II), Li et al. (2025) identified a novel fine spectral structure of solar radio bursts, termed periodic beaded stripes, and proposed a generation mechanism. Here we report additional events and develop a quantitative method to determine the physical conditions in the emission region. Periodic stripes tend to occur in the post-phase of flares and are associated with complex magnetic configurations. They repeat on sub-second timescales and show $\sim$0.1 s bead-like modulations, often accompanied by low-frequency absorptions. Modeling the chained stripes with linear kinetic theory of the double plasma resonance (DPR) instability constrains the source-region magnetic field to 0.2-1.7 G and the plasma density to (1-7) $\times 10^8$ cm $^{-3}$. The former follows the drift of individual stripes, and the latter tracks the overall trend. This study summarizes the key properties of periodic beaded stripes and establishes a quantitative DPR-based framework for coronal diagnostics.

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Chuanyang Li, Yao Chen, Bing Wang, Yutong Li, Xiangliang Kong, Hao Ning, Sulan Ni, Shuwang Chang, Zichuan Li, Yang Gao, Zhe Cui, Li Deng, Jingye Yan, Fabao Yan. 2026-04-29. Coronal Diagnostics Via Modelling Periodic-Beaded Stripes of Solar Radio Bursts. https://arxiv.org/abs/2604.26783

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