Evolution of solar and stellar coronal abundances owing to magnetic activity
David H Brooks1,2, Deborah Baker2, David M Long3
1Computational Physics, Inc. , Springfield, VA 22151, USA.
Abstract:
We discuss the evolution of solar coronal element abundances over an active region (AR) lifetime. Magneto-convection drives the complexity of magnetic fields that emerge above the photosphere. This complexity is dissipated, together with that of the overlying pre-existing fields, through dynamic events such as flares. A period of stable 'ordinary' coronal heating ensues, before the concentrated fields are dissipated through interactions with the surrounding environment. The evolution of coronal abundances can be explained by the first ionization potential (FIP) effect operating within this framework. We extend the discussion from magnetic activity on time scales of AR lifetimes (months), to the solar cycle (years), and stellar evolution (eons). The broad picture shows intriguing similarities that may prompt new investigations. This article is part of the Theo Murphy meeting issue 'Solar atmospheric abundances in space and time'.
Related Concept Videos
Magnetic Flux
Suppose a surface is divided into elements of area dA. For each element, the component of the magnetic field that is normal to the...
Magnetic Field Lines
Magnetic field lines follow several hard-and-fast rules:
Magnetic Field of a Solenoid
Consider a solenoid with 100 turns wrapped around a cylinder of...
Divergence and Curl of Magnetic Field
Magnetism
An individual magnetic pole cannot be isolated. No matter how small, every piece of a magnet contains a north pole and a south...
Magnetic Susceptibility and Permeability
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...


