Unveiling Spatiotemporal Properties of the Quasiperiodic Pulsations in the Balmer Continuum at 3600 Å in an X-class Solar White-light Flare

作者：Song De-chao, Marie Dominique, I. V. Zimovets, Qiao Li, Ying Li, Fu Yu, Yang Su, B. A. Nizamov, Ya Wang, Andrea Francesco Battaglia, Jun Tian, Li Feng, Hui Li, Weiqun Gan · 发表于：The Astrophysical Journal Letters · 年份：2025 · DOI：10.3847/2041-8213/adc4e9 · 被引用次数：9 · 研究领域：Solar and Space Plasma Dynamics、Astro and Planetary Science、Stellar, planetary, and galactic studies

Abstract Quasiperiodic pulsations (QPPs) in the Balmer continuum of solar white-light flares (WLFs) are rarely reported, and accurately pinpointing the spatial source of flaring QPPs remains a significant challenge. We present spatiotemporal characteristics of QPPs of an X2.8 two-ribbon solar WLF (SOL2023-12-14T17:02), which was well observed by the White-light Solar Telescope (WST) on board the Advanced Space-based Solar Observatory, with high-cadence imaging (1–2 s) in the Balmer continuum at 3600 Å. Combined with additional multi-instrument data, we find that the enhancement of the WLF in both Balmer and Paschen continua shows strong spatiotemporal correlation with hard X-ray (HXR) emissions. Notably, the pulses in the WST Balmer continuum exhibited a near-zero time lag with most HXR pulses, whereas soft X-ray and extreme ultraviolet emissions showed a lag of 2–3 s. Interestingly, quasi-harmonic QPPs with periods of ∼11 and ∼20 s were observed in multiple wavelengths in the rising phase of the white-light continuum. Furthermore, we employed Fourier transform to spatially locate the QPPs around 11 and 20 s, revealing that they primarily originated from the east flare ribbon, which exhibited the most substantial continuum enhancement. More interestingly, we find that the west ribbon contributed significantly to the 11 s QPP but had a weaker contribution to the 20 s QPP. Moreover, the occurrence of quasi-harmonic QPPs is temporally coincident with the rapid elongation and sep...