Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10694172 | Advances in Space Research | 2015 | 13 Pages |
Abstract
In this paper, the statistical studies on the force-freeness of photosphere magnetic fields are given. The studies are based on the vector magnetic fields observed by Solar Optical Telescope/Spectro-Polarimeter (SOT/SP) on board Hinode. Three parameters (Fx/Fp,Fy/Fp, and Fz/Fp) are introduced to investigate the force-freeness of active regions photosphere magnetic field. Various thresholds and reductions of original resolutions are selected to calculated parameters. As for the resolutions, the reductions of original resolution data by a factor of 2, 4 and 8 are applied. While for thresholds, they are calculated from individual active region with the average of 75/77/57 G for Bx/By/Bz for all original data. When the resolution are reduced by 2, 4 and 8, the corresponding averages are 72/75/55, 66/68/49 and 57/59/41 G for Bx/By/Bz, respectively. It is found that the forces indicated by Fx/Fp and Fy/Fp increase as thresholds/resolutions increase/decrease. While for Fz/Fp the trends become more complex. For low threshold, when the resolution decrease the trends of Fz/Fp are similar as those of Fx/Fp and Fy/Fp, while for high threshold the trends of Fz/Fp are different from those of Fx/Fp and Fy/Fp. For original resolution, the forces indicated by Fy/Fp increase as thresholds increase, while for others resolution they decrease as the thresholds increase contrarily.
Keywords
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Space and Planetary Science
Authors
S. Liu, J. Hao,