Formation of Coronal Flux Ropes and Onset of Coronal Mass Ejections

ROSES ID: NNH08ZDA001N      Selection Year: 2009      

Program Element: Independent Investigation

Principal Investigator: Yuhong Fan

Affiliation(s): University Corporation of Atmospheric Research

Project Member(s):
Fisher, George H Collaborator University of California

Summary:

We propose to carry out 3D MHD simulations of the formation and eruption of magnetic flux ropes in the solar corona as a result of the following photospheric flux transport processes: (1) magnetic flux emergence, (2) shear and twisting motions, and (3) turbulent diffusion. Both analytic and numerical modeling in recent years have shown that a magnetic flux rope containing helical field lines is a promising candidate for the precursor structure for coronal mass ejections, and the eruption can result from an ideal MHD process of loss of stable equilibrium. We will model the formation and evolution of coronal flux rope structures for a wide range of CME source regions, from compact active region filaments to long quiescent filaments in decaying active regions. Through these simulations we will examine the conditions for an ejective eruption of the flux rope and the possible existence of a threshold in terms of the magnetic helcity for the onset of eruption given a normal flux distribution at the lower boundary. We will study the relative importance of the flux rope's self-helicity and the mutual helicity between the flux rope and the surrounding potential field in causing eruptions and explore the possibility where the helicity of the ejected flux rope is of the opposite sign of that of the pre-existing flux rope. Finally we will model specific observed events by carrying out realistic simulations for which the lower boundary driving conditions are derived from the observed vector magnetic field evolution on the photosphere. The resulting evolution of the coronal magnetic field from the simulations will be compared with multi-wavelength coronal observations. Such comparisons will provide crucial insight into the nature of the 3D coronal magnetic field evolution associated with eruptive flares and coronal mass ejections.

Publications:

Performance Year	Reference	Investigation Type	Actions
1	Fan, Y.; (2009), The Emergence of a Twisted Flux Tube int...	not set
1	Cottaar, M.; Fan, Y.; (2009), A Model of Coronal Stream...	not set
1	Fan, Y.; (2010), On the Eruption of Coronal Flux Ropes, ...	not set
1	Fan, Y.; (2011), A Magnetohydrodynamic Model of the 2006 Dec...	not set
1	Fan, Y.; (2012), Thermal Signatures of Tether-cutting Recon...	not set
1	Chatterjee, Piyali; Fan, Yuhong; (2013), Simulation of Ho...	not set
1	Chatterjee, Piyali; Fan, Yuhong; (2014), Erratum: "S...	not set

Presentations:

Performance Year	Reference	Actions
1	Fan, Y.; (2010), On the Eruption of Coronal Flux Ropes, A...
1	Chatterjee, Piyali; Fan, Yuhong; (2014), Homologous and c...
1	Fan, Yuhong; Chatterjee, Piyali; (2014), MHD Simulations ...
1	Fan, Yuhong; Chatterjee, Piyali; (2014), MHD simulations ...

---

Export to PDF