Iron Fluorescence in X-Class Solar Flares: Aditya-L1/SoLEXS Observations
Year: 2026
Type: article
Abstract: The iron fluorescence produced by the irradiation of the photosphere by coronal X-rays is a powerful diagnostic of flare geometry. This study presents the first comprehensive analysis of Fe Kα characteristics in 47 X-class flares observed during the inaugural year of the Solar Low Energy X-ray Spectrometer (SoLEXS) on board India’s Aditya-L1 mission. Leveraging SoLEXS’s capability for simultaneous broadband continuum and line measurements, the Fe Kα flux and the exciting continuum flux (F>7.11 keV) are quantified for each event. Our results confirm the center-to-limb dependence of the fluorescence efficiency, consistent with theoretical models. These findings demonstrate that modern silicon drift detectors, despite having lower spectral resolution than traditional crystal spectrometers, provide a new diagnostic for the iron fluorescence observations.
Source: Solar Physics
Authors: Abhilash R. Sarwade, K. Sankarasubramanian, Monoj Bug, Vaishali Sharan, Kiran Lakshmipathaiah, Ankur Kushwaha, M. C. Ramadevi, Smrati Verma
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,190
Award: G2205513892
OpenAlex ID: W4414257593