A Potential New Mechanism for the Butterfly Diagram of the Solar Cycle: Latitude-dependent Radial Flux Transport
arXiv:2212.00948 · doi:10.3847/2041-8213/aca47a
Abstract
The butterfly diagram of the solar cycle is the equatorward migration of the emergence latitudes of sunspots as the solar cycle evolves. Revealing the mechanism for the butterfly diagram is essential for understanding the solar and stellar dynamo. The equatorward meridional flow at the base of the convection zone (CZ) was believed to be responsible for the butterfly diagram. However, helioseismological studies indicate controversial forms of the flow, and even present poleward flow at the base of the CZ, which poses a big challenge to the widely accepted mechanism. This motivates us to propose a new mechanism in this study. Using a data-driven Babcock-Leighton-type dynamo model, we carry out numerical simulations to explore how the latitude-dependent radial flux transport affects the latitudinal migration of the toroidal field, under different meridional flow profiles. The results indicate that when the radial transport of the poloidal field at higher latitudes is sufficiently faster, the toroidal fields of a new cycle at higher latitudes are generated earlier than that at lower latitudes, and vice versa. Thus, the butterfly diagram is suggested to correspond to the time- and latitude-dependent regeneration of the toroidal field due to the latitude-dependent radial transport of the poloidal flux.
arXiv comment8 pages, 4 figures, accepted for publication in ApJL
References in corpus (28)
- The Solar Cycle
- Detection of Equatorward Meridional Flow and Evidence of Double-Cell Meridional Circulation inside the Sun
- Sunspot group tilt angles and the strength of the solar cycle
- Full--Sphere Simulations of a Circulation--Dominated Solar Dynamo: Exploring the Parity Issue
- The crucial role of surface magnetic fields for the solar dynamo
- Meridional Circulation in Solar and Stellar Convection Zones
- On differential rotation and overshooting in solar-like stars
- Surface flux transport modeling for solar cycles 15--21: effects of cycle-dependent tilt angles of sunspot groups
- Global helioseismic evidence for a deeply penetrating Solar meridional flow consisting of multiple flow cells
- Is a deep one-cell meridional circulation essential for the flux transport Solar Dynamo?
- Magnetoconvection and dynamo coefficients: II. Field-direction dependent pumping of magnetic field
- Turbulent magnetic pumping in a Babcock-Leighton solar dynamo model
- Solar Cycle Variability Induced by Tilt Angle Scatter in a Babcock--Leighton Solar Dynamo Model
- Modeling Solar Cycles 15 to 21 Using a Flux Transport Dynamo
- Supergranules as Probes of the Sun's Meridional Circulation
- Does the Babcock--Leighton Mechanism Operate on the Sun?
- The subsurface-shear shaped solar dynamo
- Babcock-Leighton solar dynamo: the role of downward pumping and the equatorward propagation of activity
- Magnetoconvection and dynamo coefficients III: alpha-effect and magnetic pumping in the rapid rotation regime
- Surface flux evolution constraints for flux transport dynamos
- Generation solar-like differential rotation
- What sets the magnetic field strength and cycle period in solar-type stars?
- Solar Dynamo Model with Diamagnetic Pumping and Nonlocal Alpha-Effect
- A proposed paradigm for solar cycle dynamics mediated via turbulent pumping of magnetic flux in Babcock-Leighton type solar dynamos
- Sunspot tilt angles revisited: Dependence on the solar cycle strength
- A Babcock-Leighton-type Solar Dynamo Operating in the Bulk of the Convection Zone
- Meridional Circulation Dynamics in a Cyclic Convective Dynamo
- Diamagnetic pumping in a rotating convection zone