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arXiv · 2604.26036

Brightenings AnD Polarity Inversion Tracking (BADPIT) method for studying solar active region evolution before major solar flares

Augustin André-Hoffmann·Marianna B. Korsós·Alexander Nindos·Spiros Patsourakos·Manolis K. Georgoulis·Robertus Erdélyi
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Abstract

This study investigates the relationship between extreme ultraviolet (EUV) transient brightenings (TBs) and the onset of GOES X-class solar flares in active regions (ARs). We introduce the Brightenings AnD Polarity Inversion Tracking (BADPIT) method that detects TBs across multiple SDO/AIA channels. To identify TBs, we impose two independent thresholds: a 3-(sigma) intensity-based criterion and a power-law divergence approach. We apply the BADPIT method to datasets of a flaring and a non-flaring AR for 24 hours as a pathfinder to a comprehensive statistical study for a complete performance verification: the flare-productive AR 11429 and the quiescent AR 13186, both sharing a similar Hale sunspot classification. Preliminary results are encouraging: significantly more TBs are detected in the flaring AR, with up to five times more 3-(sigma) thresholded TBs, while power-law thresholded events were frequent only in the flaring AR and mostly absent in the non-flaring AR. We find that both the power-law threshold method and the 3-(sigma) method can be useful diagnostic tools for distinguishing between imminent flaring or not, several hours before the onset of major solar flares.

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Augustin André-Hoffmann, Marianna B. Korsós, Alexander Nindos, Spiros Patsourakos, Manolis K. Georgoulis, Robertus Erdélyi. 2026-04-28. Brightenings AnD Polarity Inversion Tracking (BADPIT) method for studying solar active region evolution before major solar flares. https://arxiv.org/abs/2604.26036

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