Major Surge Activity of Super-Active Region NOAA 10484

TL;DR

This study documents two major surges from NOAA 10484, analyzing their structure, dynamics, and magnetic environment, supporting magnetic reconnection as the driving mechanism.

Contribution

It provides detailed multi-wavelength observations of surges from a super-active region, highlighting their magnetic and kinematic properties, and supports magnetic reconnection models.

Findings

Surges showed funnel-shaped structures with rapid expansion.

Surges moved along open magnetic field lines at ~100 km/s.

Magnetic flux emergence and cancellation occurred at surge sites.

Abstract

We observed two surges in H-alpha from the super-active region NOAA 10484. The first surge was associated with an SF/C4.3 class flare. The second one was a major surge associated with a SF/C3.9 flare. This surge was also observed with SOHO/EIT in 195 angstrom and NoRh in 17 GHz, and showed similar evolution in these wavelengths. The major surge had an ejective funnel-shaped spray structure with fast expansion in linear (about 1.2 x 10^5 km) and angular (about 65 deg) size during its maximum phase. The mass motion of the surge was along open magnetic field lines, with average velocity about 100 km/s. The de-twisting motion of the surge reveals relaxation of sheared and twisted magnetic flux. The SOHO/MDI magnetograms reveal that the surges occurred at the site of companion sunspots where positive flux emerged, converged, and canceled against surrounding field of opposite polarity. Our observations support magnetic reconnection models for the surges and jets.