Effect of noise on sunspot magnetic field parameters

✍ Scribed by J. Linke; V. G. Utrobin

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 239 KB
• Volume: 311
• Category: Article
• ISSN: 0004-6337
• DOI: 10.1002/asna.2113110513

✦ Synopsis

Using a perturbated (noised) dipole model of a sunspot magnetic field structure we simulated the influence of background noise or apparent noise (unresolved small-scale magnetic field structure) on sunspot magnetic field parameters.

We evaluated mean values of the vertical and horizontal electric current densities bll, and kll, respectively. of the force-free parameter a and of the Lorentz force 14. For comparison we estimated lj,l and Ifl of a standard sunspot magnetic field model (return-flux model, OswRovicri 1982). Furthermore, we compared our results with those from observations resulting in estimated values of kl, for quiet sunspots. Our investigation led to the following results: the estimated values of (Id) show clearly that due to the noise the axisymmetric magnetic dipole model is clustered into several subsystems of fluxbundles. The latter are connected with a system of electric current densities of the order of bl,, -Am..' and Fl , = lo-' Am-', i.e.. this system is a noise-generated nonaxisymmetric magnetohydrostatic model.