Study on the relation of the solar coronal rotation with magnetic field structures

Abstract

Daily solar spectral irradiances (SSIs) at the spectral intervals 1–40, 116–264 and 950–1600 nm and four categories of solar small-scale magnetic elements ($$MF_{no}$$ M F no , $$MF_{anti}$$ M F anti , $$MF_{tran}$$ M F tran and $$MF_{in}$$ M F in ) are used to study the temporal variation of coronal rotation and investigate the relation of the coronal rotation with magnetic field structures through continuous wavelet transform and Pearson correlation analysis. The results reveal the contributions of different magnetic structures to the temporal variation of the rotation for the coronal atmosphere during different phases of the solar cycle. During the solar maximum, the temporal variation of rotation for the coronal plasma atmosphere is mainly dominated by the small-scale magnetic elements of $$MF_{anti}$$ M F anti ; whereas during the epochs of the relatively weak solar activity, it is controlled by the joint effect of the small-scale magnetic elements of both $$MF_{anti}$$ M F anti and $$MF_{in}$$ M F in . The weaker the solar activity, the stronger the effect of $$MF_{in}$$ M F in would be. Furthermore, this study presents an explanation for the inconsistent results for the coronal rotation issue among the previous studies, and also reveals the reason why the coronal atmosphere rotates faster than the lower photosphere.