Automated detection of coronal mass ejections in three-dimensions using multi-viewpoint observations

TL;DR

This paper introduces an automated triangulation method for detecting and analyzing the three-dimensional structure of coronal mass ejections using multi-viewpoint coronagraph data, improving accuracy and robustness.

Contribution

The paper presents the Automated CME Triangulation (ACT) method, a novel approach for 3D CME detection that works with synthetic and real data, even with partial observations.

Findings

Achieves 7.14-degree accuracy in synthetic CME position detection

Performs well with real coronagraph data, including halo CMEs

Remains effective despite loss of one observational instrument

Abstract

A new, automated method of detecting coronal mass ejections (CMEs) in three dimensions for the LASCO C2 and STEREO COR2 coronagraphs is presented. By triangulating isolated CME signal from the three coronagraphs over a sliding window of five hours, the most likely region through which CMEs pass at 5 solar radii is identified. The centre and size of the region gives the most likely direction of propagation and approximate angular extent. The Automated CME Triangulation (ACT) method is tested extensively using a series of synthetic CME images created using a wireframe flux rope density model, and on a sample of real coronagraph data; including halo CMEs. The accuracy of the angular difference between the detection and true input of the synthetic CMEs is 7.14 degrees, and remains acceptable for a broad range of CME positions relative to the observer, the relative separation of the three observers and even through the loss of one coronagraph. For real data, the method gives results that compare well with the distribution of low coronal sources and results from another instrument and technique made further from the Sun. The true three dimension (3D)-corrected kinematics and mass/density are discussed. The results of the new method will be incorporated into the CORIMP database in the near future, enabling improved space weather diagnostics and forecasting.