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Title: Temporal Variation of the Rotation of the Solar Mean Magnetic Field

Abstract

Based on continuous wavelet transformation analysis, the daily solar mean magnetic field (SMMF) from 1975 May 16 to 2014 July 31 is analyzed to reveal its rotational behavior. Both the recurrent plot in Bartels form and the continuous wavelet transformation analysis show the existence of rotational modulation in the variation of the daily SMMF. The dependence of the rotational cycle lengths on solar cycle phase is also studied, which indicates that the yearly mean rotational cycle lengths generally seem to be longer during the rising phase of solar cycles and shorter during the declining phase. The mean rotational cycle length for the rising phase of all of the solar cycles in the considered time is 28.28 ± 0.67 days, while for the declining phase it is 27.32 ± 0.64 days. The difference of the mean rotational cycle lengths between the rising phase and the declining phase is 0.96 days. The periodicity analysis, through the use of an auto-correlation function, indicates that the rotational cycle lengths have a significant period of about 10.1 years. Furthermore, the cross-correlation analysis indicates that there exists a phase difference between the rotational cycle lengths and solar activity.

Authors:
; ;  [1]
  1. Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)
Publication Date:
OSTI Identifier:
22663726
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 153; Journal Issue: 4; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CORRELATION FUNCTIONS; CORRELATIONS; DATA ANALYSIS; MAGNETIC FIELDS; MODULATION; PERIODICITY; ROTATION; SOLAR ACTIVITY; SOLAR CYCLE; SUN; TRANSFORMATIONS

Citation Formats

Xie, J. L., Shi, X. J., and Xu, J. C., E-mail: xiejinglan@ynao.ac.cn. Temporal Variation of the Rotation of the Solar Mean Magnetic Field. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA6199.
Xie, J. L., Shi, X. J., & Xu, J. C., E-mail: xiejinglan@ynao.ac.cn. Temporal Variation of the Rotation of the Solar Mean Magnetic Field. United States. doi:10.3847/1538-3881/AA6199.
Xie, J. L., Shi, X. J., and Xu, J. C., E-mail: xiejinglan@ynao.ac.cn. Sat . "Temporal Variation of the Rotation of the Solar Mean Magnetic Field". United States. doi:10.3847/1538-3881/AA6199.
@article{osti_22663726,
title = {Temporal Variation of the Rotation of the Solar Mean Magnetic Field},
author = {Xie, J. L. and Shi, X. J. and Xu, J. C., E-mail: xiejinglan@ynao.ac.cn},
abstractNote = {Based on continuous wavelet transformation analysis, the daily solar mean magnetic field (SMMF) from 1975 May 16 to 2014 July 31 is analyzed to reveal its rotational behavior. Both the recurrent plot in Bartels form and the continuous wavelet transformation analysis show the existence of rotational modulation in the variation of the daily SMMF. The dependence of the rotational cycle lengths on solar cycle phase is also studied, which indicates that the yearly mean rotational cycle lengths generally seem to be longer during the rising phase of solar cycles and shorter during the declining phase. The mean rotational cycle length for the rising phase of all of the solar cycles in the considered time is 28.28 ± 0.67 days, while for the declining phase it is 27.32 ± 0.64 days. The difference of the mean rotational cycle lengths between the rising phase and the declining phase is 0.96 days. The periodicity analysis, through the use of an auto-correlation function, indicates that the rotational cycle lengths have a significant period of about 10.1 years. Furthermore, the cross-correlation analysis indicates that there exists a phase difference between the rotational cycle lengths and solar activity.},
doi = {10.3847/1538-3881/AA6199},
journal = {Astronomical Journal (Online)},
number = 4,
volume = 153,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
  • Subsets of the solar mean-magnetic-field measurements have been studied to determine the conditions for which a solar-type differential rotation signal may be seen in stellar observations. Stellar differential rotation may be detected from mean-magnetic-field measurements if: (1) the number of observations is relatively high; (2) the noise level is less than roughly 25 percent of the maximum field strength value; and (3) the sign of the magnetic field has been determined. The combination of synoptic polarization measurements with those of Zeeman broadening may permit the detection of stellar differential rotation. 35 refs.
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