2026/04/23 by Yongliang Song, Yongliang 永亮 Song 宋 · 1 voice
Physics and Astronomy · #Flare #Flux (metallurgy) #Gamma-ray bursts and supernovae #Magnetic flux #Magnetic reconnection #Nanoflares #Solar and Space Plasma Dynamics #Solar flare #Stellar, planetary, and galactic studies #Sunspot #astro-ph.SR
paper · pdf · doi:10.3847/1538-4357/ae650e
arxiv published 2026/04/23 · arxiv updated 2026/04/23 · openalex created_date 2026/05/19 · openalex publication_date 2026/05/19 · openalex updated_date 2026/05/23
Abstract White-light flares (WLFs) usually tend to be very large flares. Nevertheless, several small and compact WLFs have been reported and thought to be produced by low-height magnetic reconnection. However, whether low-height magnetic reconnection can efficiently produce WLFs remains unclear. For the first time, we conduct a statistical study of the white-light (WL) emission in compact flares to address this question. Using over a decade of observations from the Solar Dynamics Observatory, we identify 28 compact flares, including 19 C-class and 9 B-class flares. We find these compact flares can be classified into three types based on the magnetic configuration of the flare, corresponding to the U-shape loop (type I), the flux emergence near sunspot (type II), and the fan-spine like structure (type III). For each type, the flares numbers are 9 (7 C-class and 2 B-class), 9 (3 C-class and 6 B-class) and 10 (9 C-class and 1 B-class), respectively. We find the occurrence rate of WLFs in compact flares is ∼60.7% (17/28), and for the C-class the rate can be up to ∼89.5% (17/19). No WLF was found in B-class compact flares. The occurrence rates for the three types are ∼77.8% (7/9), ∼11.1% (1/9), and 90% (9/10), respectively. For the C-class flares, the occurrence rates for the three types are 100% (7/7), ∼33.3% (1/3) and 100% (9/9), respectively. Our results suggest type-I and type-III compact flares are more likely to produce WL emissions.