# Multiwavelength Observations of a Flux Rope Formation by Series of Magnetic Reconnection in the Chromosphere

## TL;DR

This study presents high-resolution observations of chromospheric magnetic reconnection leading to flux rope formation during homologous solar flares, highlighting the role of flux cancellation and magnetic twist in flux rope dynamics.

## Contribution

It provides the first detailed evidence of chromospheric loop reconnection and flux rope formation linked to rapid flux cancellation, using high-resolution NST observations.

## Key findings

- Reconnection of chromospheric Hα loops caused flux rope formation.
- Flux cancellation rate was approximately 3.44×10^{20} Mx/h during flares.
- The flux rope was unstable and failed to produce a coronal mass ejection.

## Abstract

Using high-resolution observations from the 1.6 m New Solar Telescope (NST) operating at the Big Bear Solar Observatory (BBSO), we report direct evidence of merging/reconnection of cool H$\alpha$ loops in the chromosphere during two homologous flares (B- and C-class) caused by a shear motion at the footpoint of two loops. The reconnection between these loops caused the formation of an unstable flux rope which showed counterclockwise rotation. The flux rope could not reach the height of torus instability and failed to form a coronal mass ejection. The HMI magnetograms revealed rotation of the negative/positive (N1/P2) polarity sunspots in the opposite directions, which increased the right and left-handed twist in the magnetic structures rooted at N1/P2. Rapid photospheric flux cancellation (duration$\sim$20-30 min, rate$\approx$3.44$\times$10$^{20}$ Mx h$^{-1}$) was observed during and even after the first B6.0 flare and continued until the end of the second C2.3 flare. The RHESSI X-ray sources were located at the site of the loop's coalescence. To the best of our knowledge, such a clear interaction of chromospheric loops along with rapid flux cancellation has not been reported before. These high-resolution observations suggest the formation of a small flux rope by a series of magnetic reconnection within chromospheric loops associated with very rapid flux cancellation.