We propose an observational study of the initiation and acceleration of coronal mass ejections (cmes) in the solar corona, to establish a quantitative relationship between CME energetics and…

The National Aeronautics and Space Administration (NASA) awarded a $450,946.15 grant to Montana State University for a research project studying the initiation and acceleration of coronal mass ejections (CMEs) in the solar corona. The observational study will analyze data from NASA's Solar Dynamics Observatory (SDO) and Solar TErrestrial RElations Observatory (STEREO) to establish a quantitative relationship between CME energetics and magnetic reconnection. The research aims to improve understanding of CME initiation and acceleration, providing observational constraints for CME models. This grant supports NASA's mission goals to understand magnetic field configurations leading to CMEs, filament eruptions, and solar flares, as well as the Decadal Survey's science goals to determine the origins of solar activity and characterize fundamental processes in the heliosphere. The grant does not have a set-aside designation.

We propose an observational study of the initiation and acceleration of coronal mass ejections (cmes) in the solar corona, to establish a quantitative relationship between CME energetics and magnetic reconnection. Observations from the stereo will be analyzed to reconstruct the time-height profile and measure the velocity and acceleration of cmes. Observations from the AIA and HMI onboard SDO will be analyzed to measure magnetic reconnection rate in flares, and other surface properties associated with the cmes. The datasets from 2010 through 2014 will be explored, and a large sample of events will be analyzed, in which solar flares and magnetic fields are observed by SDO on the disk whereas cmes are observed by stereo from the limb simultaneously. The goal of the proposed research is to understand CME initiation and acceleration in the sun's corona. We will employ observations from multiple spacecraft to find out when and where magnetic reconnection takes place, when and where CME eruption is initiated, and when and for how long CME is accelerated. We will establish observationally the temporal-spatial relationship and quantitative comparison between magnetic reconnection signatures and CME eruptions in a large sample of events with varying magnetic configurations. These observational measurements with an appropriate scope, rather than random case studies, provide constraints and observed parameter space for CME models, although the proposed research will not include CME modeling. 2. List of missions: SDO: AIA, HMI; stereo (a and b): euvi, COR1, COR2; soho 3. Methodology: we will explore observations by SDO and stereo from 2010 - 2014, expanding upon the existing catalogs to establish a large database of jointly observed and unambiguously associated events. With these datasets, we will construct time-height profiles using stereo observations of cmes and measure velocity, acceleration, mass, and kinetic energy of cmes. We will measure reconnection rate using SDO observations of solar flares and magnetic fields, and track other surface signatures like coronal dimming. With these measurements, we will establish the timing relationship between CME initiation and onset of magnetic reconnection, and the timing relationship between CME acceleration and flare reconnection in the early phase of the eruption, with the highest possible time cadence in a large sample. We will establish the quantitative relationship between the peak velocity, mass, and kinetic energy of cmes and total reconnection flux measured in flares. We will also measure other geometric properties of the CME-flare system and their evolution, when the CME is close to the sun (within 3-5 solar radii), and characterize the magnetic configuration of the CME source regions. We will develop a comprehensive method to categorize and synthesize these measurements towards improving our understanding of the association between CME properties and solar surface properties. 4. Relevance to mission goals and decadal survey science goals the proposed research meets the SDO mission goals to improve our understanding of "what magnetic field configurations lead to the cmes, filament eruptions, and flares that produce energetic particles and radiation". The proposed research is compliant with the stereo mission goal to "understand the causes and mechanisms of coronal mass ejection (CME) initiation". The proposed research addresses two science goals in the solar and space physics decadal survey to "determine the origins of the sun s activity and predict the variations in the space environment" (key science goal 1) and "discover and characterize fundamental process that occur both within the heliosphere and throughout the universe" (key science goal 4).