Back to Search
Start Over
Chinese sunspot drawings and their digitization − (IV) differential rotation profile determined from hand-drawing records.
- Source :
-
Journal of Astrophysics & Astronomy . Oct2021, Vol. 42 Issue 2, p1-9. 9p. - Publication Year :
- 2021
-
Abstract
- It is necessary to better understand the dynamic process of solar differential rotation. Here the hand-drawing sunspot group records from 1958 to 2015 of Yunnan Observatories (YNAO) are used to study the solar rotation profile. Firstly, the rotation profile in each solar cycle 19-23 is calculated. Secondly, the rotation parameters (equatorial rotation velocity A and differential gradient B) of YNAO are compared with the well-known earlier results. Finally, the rotation parameters in the northern and southern hemispheres during each solar cycle 19-23 are summarized. The main conclusions we reached are as follows: (1) The average difference of the equatorial rotation velocity and differential gradient, between YNAO sunspot and other sunspot datasets, are 0.09 and 0.4, respectively. (2) The magnitudes of the gradient B in the northern hemisphere are larger than that in the southern hemisphere at even-number cycles, and it will approximately reverse at odd-number cycles. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 02506335
- Volume :
- 42
- Issue :
- 2
- Database :
- Academic Search Index
- Journal :
- Journal of Astrophysics & Astronomy
- Publication Type :
- Academic Journal
- Accession number :
- 151391127
- Full Text :
- https://doi.org/10.1007/s12036-021-09766-8