# Two Step Filament Eruption During 14-15 March 2015

## TL;DR

This study analyzes a unique two-step filament eruption in March 2015, combining multi-instrument observations to understand the eruption process and its association with a halo CME.

## Contribution

It provides detailed observational evidence and analysis of a two-step filament eruption, highlighting the role of successive instability zones in the eruption process.

## Key findings

- Filament exhibited a two-step eruption with a 12-hour pause at ~125 Mm altitude.
- The eruption was associated with a halo CME and jet activity in the active region.
- Decay index analysis suggests multiple instability zones contributed to the eruption.

## Abstract

We present here an interesting two-step filament eruption during 14-15 March 2015. The filament was located in NOAA AR 12297 and associated with a halo Coronal Mass Ejection (CME). We use observations from the Atmospheric Imaging Assembly (AIA) and Heliospheric Magnetic Imager (HMI) instruments onboard the Solar Dynamics Observatory (SDO), and from the Solar and Heliospheric Observatory (SOHO) Large Angle and Spectrometric Coronagraph (LASCO). We also use H-alpha data from the Global Oscillation Network Group (GONG) telescope and the Kanzelhoehe Solar Observatory. The filament shows a first step eruption on 14 March 2015 and it stops its rise at a projected altitude ~ 125 Mm on the solar disk. It remains at this height for ~ 12 hrs. Finally it eruptes on 15 March 2015 and produced a halo CME. We also find jet activity in the active region during both days, which could help the filament de-stabilization and eruption. The decay index is calculated to understand this two-step eruption. The eruption could be due to the presence of successive instability-stability-instability zones as the filament is rising.