Effects of Radiative Diffusion on Thin Flux Tubes in Turbulent Solar-like Convection

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 (Astrophys. J. 741, 11, 2011; Solar Phys. 287, 239, 2013), now taking into account the influence of radiative heating on 10(22) Mx flux tubes, corresponding to flux tubes of large active regions. Our simulations show that flux tubes of a parts per thousand currency signaEuro parts per thousand 60 kG that are subject to solar-like convective flows do not anchor in the overshoot region, but rather drift upward because of the increased buoyancy of the flux tube earlier in its evolution, which results from including radiative diffusion. Flux tubes of magnetic field strengths ranging from 15 kG to 100 kG have rise times of a parts per thousand currency signaEuro parts per thousand 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. Moreover, 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.