42 citations · 175 across the 9 of their papers we have counts for
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Reconstructing solar magnetic fields from historical observations VIII. AIA 1600 Å contrast as a proxy of solar magnetic fields
Ismo Tähtinen, Ilpo Virtanen, Alexei A. Pevtsov +1
The bright regions in the solar chromosphere and temperature minimum have a good spatial correspondence with regions of intense photospheric magnetic field. Their observation start…
On a limitation of Zeeman polarimetry and imperfect instrumentation in representing solar magnetic fields with weaker polarization signal
Alexei A. Pevtsov, Yang Liu, Ilpo Virtanen +4
Full disk vector magnetic fields are used widely for developing better understanding of large-scale structure, morphology, and patterns of the solar magnetic field. The data are al…
A new signal of the solar magnetic cycle: Opposite shifts of weak magnetic field distributions in the two hemispheres
Tibebu Getachew, Ilpo Virtanen, Kalevi Mursula
We study the asymmetric distribution of weak photospheric magnetic field values in the two hemispheres separately using synoptic maps from SDO/HMI, SOLIS/VSM and WSO during solar c…
Reconstructing solar magnetic fields from historical observations V. Sunspot magnetic field measurements at Mount Wilson Observatory
Alexei A. Pevtsov, Kseniya A. Tlatova, Alexander A. Pevtsov +7
Context. Systematic observations of magnetic field strength and polarity in sunspots began at Mount Wilson Observatory (MWO), USA in early 1917. Except for a few brief interruption…
Asymmetric distribution of weak photospheric magnetic field values
Tibebu Getachew, Ilpo Virtanen, Kalevi Mursula
We use the synoptic maps of the photospheric magnetic field observed at Wilcox Solar Observatory, Mount Wilson Observatory, Kitt Peak, SOHO/MDI, SOLIS/VSM, and SDO/HMI to study the…
Tilt of sunspot bipoles in Solar Cycles 15 to 24
Ksenia Tlatova, Andrey Tlatov, Alexei Pevtsov +7
We use recently digitized sunspot drawings from Mount Wilson Observatory to investigate the latitudinal dependence of tilt angles of active regions and its change with solar cycle.…
Bihelical spectrum of solar magnetic helicity and its evolution
Nishant K. Singh, Maarit J. Käpylä, Axel Brandenburg +3
Using a recently developed two-scale formalism to determine the magnetic helicity spectrum (Brandenburg et al. 2017), we analyze synoptic vector magnetograms built with data from t…