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:
52
53
520
521
523
524
52-1
52-6
41.00
29.35
29.31
29.33
29.27
29.05
03.06.01
03.05.01
03.04.03
2
223
614
6135
SCI004000
SCI005000
53
520
521
523
524
52-1
52-6
41.00
29.35
29.31
29.33
29.27
29.05
03.06.01
03.05.01
03.04.03
2
223
614
6135
SCI004000
SCI005000
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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