Double-periodic pulsations simultaneously detected in mid-infrared and hard X-ray emissions during an X1.5 flare

Abstract

Quasi-periodic pulsations (QPPs) have been observed in a broad electromagnetic spectrum, encompassing radio, ultraviolet, white light, X-rays, and Gama-rays. Yet, flare-associated QPPs remain rarely detected in mid-infrared emission. Here, we explored dual-period QPPs in the mid-infrared waveband, hard X-rays (HXRs), and microwave emission during an X1.5 flare on 2024 December 30 (SOL2024-12-30T04:01). Flare QPPs with dual quasi-periods at about 8.5 s and 4.6 s were simultaneously detected in the AIMS 8-10 um, Fermi 26-50 keV, and HXI 20-50 keV wavebands during the impulsive phase. Imaging observations show that the flare emission sources in the mid-infrared, HXR, and white-light wavebands are spatially coincident. Mid-infrared emissions are primarily localized at the loop top and double footpoints, which are connected by a hot plasma loop. These observational features support intermittent and rapid energy release via oscillatory magnetic reconnection during the solar flare. Differential emission measure analysis confirms fast sausage waves in flaring loops, while the WST observation indicates a white-light flare. We localized the flare QPPs with double periods in mid-infrared, HXR, and microwave emissions during a white-light flare. The flare-associated QPPs may be attributed to a quasi-periodic regime of magnetic reconnection, with the double periods likely modulated by quasi-harmonics of sausage waves.