High-resolution Observations of a C9.3 White-light Flare and Its Impact on the Solar Photosphere

TL;DR

This study provides high-resolution observations of a C9.3 white-light solar flare, revealing photospheric impacts likely driven by Alfvén wave energy transport, with implications for understanding flare energy mechanisms.

Contribution

It offers detailed observational evidence linking white-light flare impacts on the photosphere to Alfvén wave propagation, a novel insight into flare energy transport.

Findings

Detection of white-light kernels connected by filamentary brightenings.

Observation of vortex flows and magnetic field amplification during the flare.

Evidence supporting Alfvén waves as a mechanism for energy transfer to the photosphere.

Abstract

We present a detailed analysis of a C9.3 white-light flare using high-resolution observations from the New Vacuum Solar Telescope (NVST). The flare occurred near the eastern solar limb on September 11, 2023, within NOAA AR 13431, and produced beam electrons with energies just below 50 keV as observed by the the Hard X-ray Imager (HXI) onboard the Advanced Space-based Solar Observatory (ASO-S). Two white-light flare kernels were detected in the TiO band, connected by filamentary brightenings aligned with penumbral fibrils, suggesting a photospheric contribution to the white-light emission. Notably, the impact of the flare on the solar photosphere was characterized by sudden vortex flows and significant amplification of magnetic field in the white-light flare kernel region. We infer that this impact is driven by the propagation of flare-generated Alfv\'en wave pulses, which deposited energy into the photosphere. These observations support the potential role of the Alfv\'en wave mechanism in driving energy transport and heating during white-light flares.