SOLAR CONVECTION AS THE PRODUCER OF MAGNETIC BIPOLES

摘要

A mechanism for the in situ formation of bipolar magnetic configurations, alternative to the well-known rising-tube mechanism, is considered. Cellular magnetoconvection is simulated numerically. The initial magnetic field is assumed to be fairly weak and directed horizontally. A pattern of small-amplitude hexagonal cells is specified initially. A hexagonal convection cell can substantially amplify the magnetic field and impart bipolar configurations to it. Depending on the parameters, the amplified field may form either a simple pair of magnetic islands, opposite in polarity, or a more complex superposition of bipoles. In particular, very compact magnetic elements of strong field can form. The resulting pattern of magnetic-field evolution is in better agreement with observations than the rising-tube model.