2015/03/27 by Maria A. Weber, Yuhong Fan · 14 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics #Buoyancy #Convection #Convection zone #Flux (metallurgy) #Flux tube #Magnetic field #Magnetic flux #Materials science #Mechanics #Optics #Physics #Radiative cooling #Radiative flux #Radiative transfer #Solar and Space Plasma Dynamics #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1007/s11207-015-0674-3
published in Solar Physics 290(5), 1295-1321 (Springer Science+Business Media) · Accepted for publication to Solar Physics
arxiv created 2015/03/27 · openalex publication_date 2015/04/20 · arxiv updated 2015/06/03 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We study the combined effects of convection and radiative diffusion on the evolution of thin magnetic flux tubes in the solar interior. Radiative diffusion is the primary supplier of heat to convective motions in the lower convection zone, and it results in a heat input per unit volume of magnetic flux tubes that has been ignored by many previous thin flux tube studies. We use a thin flux tube model subject to convection taken from a rotating spherical shell of turbulent, solar-like convection as described by Weber, Fan, and Miesch (2011, Astrophys. J., 741, 11; 2013, Solar Phys., 287, 239), now taking into account the influence of radiative heating on flux tubes of large-scale active regions. Our simulations show that flux tubes of less than or equal to 60 kG subject to solar-like convective flows do not anchor in the overshoot region, but rather drift upward due to the increased buoyancy of the flux tube earlier in its evolution as a result of the inclusion of radiative diffusion. Flux tubes of magnetic field strengths ranging from 15 kG to 100 kG have rise times of less than or equal to 0.2 years, and exhibit a Joy's Law tilt-angle trend. Our results suggest that radiative heating is an effective mechanism by which flux tubes can escape from the stably stratified overshoot region, and that flux tubes do not necessarily need to be anchored in the overshoot region to produce emergence properties similar to those of active regions on the Sun.