ON THE CAUSE OF SOLAR-LIKE EQUATORWARD MIGRATION IN GLOBAL CONVECTIVE DYNAMO SIMULATIONS

Abstract

We present results from four convectively-driven stellar dynamo simulations\nin spherical wedge geometry. All of these simulations produce cyclic and\nmigrating mean magnetic fields. Through detailed comparisons we show that the\nmigration direction can be explained by an $\\alpha\\Omega$ dynamo wave following\nthe Parker--Yoshimura rule. We conclude that the equatorward migration in this\nand previous work is due to a positive (negative) $\\alpha$ effect in the\nnorthern (southern) hemisphere and a negative radial gradient of $\\Omega$\noutside the inner tangent cylinder of these models. This idea is supported by a\nstrong correlation between negative radial shear and toroidal field strength in\nthe region of equatorward propagation.\n