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arXiv · 2504.17095

ALEXIS: Recreating the X-Ray Emission from the Full Solar Disk as a Linear Combination of Discrete Regions in the Extreme Ultraviolet and Soft X-Rays

Abstract

Despite a wealth of multi-wavelength, spatially resolved, time-domain solar activity data, an accurate and complete temporo-spatial solar flare census is unavailable, which impedes our understanding of the physics of flare production. We present an Automatically Labeled EUV and X-ray Incident SolarFlares (ALEXIS) pipeline, designed to decompose the X-Ray flux of the full solar disk into a minimum set of discrete regions on the Solar surface. ALEXIS returns an average RMSE between the XRS time series and the discrete EUV signals of 0.066 $\pm$ 0.036 for a randomly selected test bed sample of 1000 hour-long data segments from May 2010 - March 2020. Flare emission that requires multiple regions was found to be synchronous: flares occurring at the same time, sympathetic: flares separated by minutes, or needed to capture the background emission before and/or after the main flare. ALEXIS uses the original full resolution and cadence of both the Atmospheric Imaging Assembly Instrument and the GOES13-15 Solar X-Ray Imager. Comparison of the ALEXIS catalog with those produced by SWPC and SolarSoft show that these canonical databases need revisiting for 62$\%$ and 15$\%$ of the sub-sample, respectively. Additionally, we increased the number of flares reported by SWPC and SolarSoft by 15$\%$. Our pipeline misses 6.7$\%$ of the 1057 flare sub-sample and returns 5$\%$ of false positives from 1211 flares reported by ALEXIS. The ALEXIS catalog returns flare peak times, coordinates, the corrected scaled XRay magnitude, and the associated NOAA active region with a HARP identifier number independently from any external data products.

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Jorge R Padial Doble, Kelly Holley-Bockelmann. 2025-04-23. ALEXIS: Recreating the X-Ray Emission from the Full Solar Disk as a Linear Combination of Discrete Regions in the Extreme Ultraviolet and Soft X-Rays. https://doi.org/10.3847/1538-4365%2Fadbe35

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