Solar Interior Currents Presumed by Solar Surface Magnetic Fields
- Resource Type
- Article
- Authors
- 김보경; 이유
- Source
- Journal of the Korean Astronomical Society, 56(2), pp.187-194 Dec, 2023
- Subject
- 천문학
- Language
- English
- ISSN
- 2288-890X
1225-4614
The remote sensing technique of measuring the magnetic field was applied first to the sunspots among the astronomical objects by Hale (1908). Later Babcock (1961) showed the solar surface magnetic field on a global scale is a dipole in first-order approximation and this dipole field reverses once in each solar cycle. The Wilcox Solar Observatory (WSO) supplies the spherical harmonics coefficients of the solar corona magnetic field of each Carrington Rotation calculated based on the solar surface photospheric magnetic field remotely sensed. To presume the internal current system producing the global solar coronal magnetic field structure and evolution of the Sun, we calculate the multipole components of the solar magnetic field using the WSO data from 1976 to 2019. The prominent cycle components over the last 4 solar activity cycles are axis-symmetric fields of the dipole and octupole. This implies that the current inversion driving the solar magnetic field reversal originates from the equatorial region and spreads to the whole globe. Thus, the more accurate solar dynamo model must include an explanation of the origin and evolution of such solar internal current dynamics.