Modelling photospheric magnetoconvection in the weak field regime
Seminar Room 1, Newton Institute
High resolution observations can now provide detailed information regarding the complex interactions between convective motions and magnetic fields in the solar photosphere. This problem is investigated theoretically through numerical simulation of three dimensional compressible magnetoconvection in a large aspect ratio box. Attention is focused on the regime in which the imposed vertical magnetic field is relatively weak. Turbulent convection patterns and intermittent field structures are found. For a moderately weak imposed field, large elongated magnetic structures are found, similar to those found in plage regions on the solar surface. Decreasing the total magnetic flux further causes the magnetic structures to become almost point-like, similar to those seen in the quiet Sun. Calculation of the fractal dimension allows quantitative analysis of the surface distribution of the magnetic field. Although coming from idealised simulations, these results can be closely related to solar observations.