DIFFERENTIAL ROTATION OF SUNSPOTS OF DIFFERENT MAGNETIC POLARITY
Authors:
1.
Kislovodsk Mountain Astronomical Station of the Pulkovo observatory
2.
Kislovodsk Mountain Astronomical Station of the Pulkovo observatory
Type:
Сonference article
Published:
27.12.2024
Subject area:
UDC 52
UDC 53
UDC 520
UDC 521
UDC 523
UDC 524
UDC 52-1
UDC 52-6
CSCSTI 41.00
CSCSTI 29.35
CSCSTI 29.31
CSCSTI 29.33
CSCSTI 29.27
CSCSTI 29.05
Russian Classification of Professions by Education 03.06.01
Russian Classification of Professions by Education 03.05.01
Russian Classification of Professions by Education 03.04.03
Russian Library and Bibliographic Classification 2
Russian Library and Bibliographic Classification 223
Russian Trade and Bibliographic Classification 614
Russian Trade and Bibliographic Classification 6135
BISAK SCI004000 Astronomy
BISAK SCI005000 Physics / Astrophysics
UDC 53
UDC 520
UDC 521
UDC 523
UDC 524
UDC 52-1
UDC 52-6
CSCSTI 41.00
CSCSTI 29.35
CSCSTI 29.31
CSCSTI 29.33
CSCSTI 29.27
CSCSTI 29.05
Russian Classification of Professions by Education 03.06.01
Russian Classification of Professions by Education 03.05.01
Russian Classification of Professions by Education 03.04.03
Russian Library and Bibliographic Classification 2
Russian Library and Bibliographic Classification 223
Russian Trade and Bibliographic Classification 614
Russian Trade and Bibliographic Classification 6135
BISAK SCI004000 Astronomy
BISAK SCI005000 Physics / Astrophysics
Language:
English
Keywords:
Sun: sunspots; rotation
Abstract (English):
The rotation rate was analyzed depending on the latitude of individual sunspots of different magnetic polarity. To identify sunspots, we used observations of the SDO/HMI space observatory in the period 2010-2024 in the continuum and observations of magnetic fields at the same time. It was found that the rotation rate of sunspots depends on the magnetic polarity in the 22-year Hale magnetic cycle. The dependence of the rotation rate of sunspots on latitude can be written for sunspots of leading polarity, the rotation rate can be approximated by the formula: $\omega_{\rm ld}(\theta)=14.574-2.225 \rm{sin}^{\rm 2}\theta-0.02 \rm{ sin}^{\rm 4}\theta$ deg/day. For sunspots of trailing polarity $\omega_{\rm tr}(\theta)=14.216-2.60 \rm{sin}^{\rm 2}\theta-0.01 \rm{ sin}^{\rm 4}\theta$ deg/day. Thus, sunspots of leading polarity rotate more than $\sim2\%$ faster than sunspots of trailing polarity. For sunspots with magnetic flux $\Phi>2\cdot 10^{20}$ Mx, the rotation rate practically does not change with increasing magnetic flux.
The rotation rate was analyzed depending on the latitude of individual sunspots of different magnetic polarity. To identify sunspots, we used observations of the SDO/HMI space observatory in the period 2010-2024 in the continuum and observations of magnetic fields at the same time. It was found that the rotation rate of sunspots depends on the magnetic polarity in the 22-year Hale magnetic cycle. The dependence of the rotation rate of sunspots on latitude can be written for sunspots of leading polarity, the rotation rate can be approximated by the formula: $\omega_{\rm ld}(\theta)=14.574-2.225 \rm{sin}^{\rm 2}\theta-0.02 \rm{ sin}^{\rm 4}\theta$ deg/day. For sunspots of trailing polarity $\omega_{\rm tr}(\theta)=14.216-2.60 \rm{sin}^{\rm 2}\theta-0.01 \rm{ sin}^{\rm 4}\theta$ deg/day. Thus, sunspots of leading polarity rotate more than $\sim2\%$ faster than sunspots of trailing polarity. For sunspots with magnetic flux $\Phi>2\cdot 10^{20}$ Mx, the rotation rate practically does not change with increasing magnetic flux.
Keywords:
Sun: sunspots; rotation
Sun: sunspots; rotation
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