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Transactions of the International Astronomical Union, 1982 This report summarizes research on solar activity over an almost three-year period from January 1, 1979, till the end of June 1981. In preparing this report we respected the advice of the I.A.U. Executive Committee to cover the highlights of work carried out in the field of solar physics relevant to our Commission, and avoiding double work.
H. Yoshimura +10 more
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The place of the Sun among the Sun-like stars [PDF]
, 2013 Context. Monitoring of the photometric and chromospheric HK emission data series of stars similar to the Sun in age and average activity level showed that there is an empirical correlation between the average stellar chromospheric activity level and the ...
Cessateur, G. +3 more
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GONG p-mode frequency changes with solar activity [PDF]
, 1999 We present a correlation analysis of GONG p-mode frequencies with nine solar activity indices for the period 1995 August to 1997 August. This study includes spherical harmonic degree in the range 2 to 150 and the frequency range of 1500-3500 \mu Hz ...
A. Bhatnagar +4 more
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Changes in the sensitivity of solar p-mode frequency shifts to activity over three solar cycles [PDF]
, 2018 Low-degree solar p-mode observations from the long-lived Birmingham Solar Oscillations Network (BiSON) stretch back further than any other single helioseismic data set.
Basu, S. +5 more
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The onset of solar cycle 24: What global acoustic modes are telling us
, 2009 We study the response of the low-degree, solar p-mode frequencies to the unusually extended minimum of solar surface activity since 2007. A total of 4768 days of observations collected by the space-based, Sun-as-a-star helioseismic GOLF instrument are ...
Beer +22 more
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Astronomy & AstrophysicsContext. Switchbacks–transient, large-angle deflections of the interplanetary magnetic field–pervade the solar wind, yet their origin remains disputed. Current ex situ theories, notably coronal jets and interchange reconnection, are typically tested on ...
Dai Fanzhuo +5 more
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Eos, Transactions American Geophysical Union, 1991 Perhaps the most newsworthy item of recent times concerning solar activity is its unprecedented strength during the rising phase of its current 11‐year cycle. Examples of its potency include a major, well‐observed solar flare in March 1989 that launched an unusually powerful blast wave that, hitting Earth, caused spectacular low‐latitude auroras and ...
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Scale sequentially CLEAN for Mingantu Spectral Radioheliograph
Solar-Terrestrial Physics, 2019 MingantU SpEctral Radioheliograph (MUSER) is a solar-dedicated radio heliograph, adopting aperture synthesis technique to image the Sun in the frequency range of 0.4 GHz to 15 GHz.
Jun Cheng, Yihua Yan, Dong Zhao, Long Xu
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The Origin of Enhanced Activity in the Suns of M67
, 2009 We report the results of the analysis of high resolution photospheric line spectra obtained with the UVES instrument on the VLT for a sample of 15 solar-type stars selected from a recent survey of the distribution of H and K chromospheric line strengths ...
A. Reiners +9 more
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Understanding solar cycle variability
, 2017 The level of solar magnetic activity, as exemplified by the number of sunspots and by energetic events in the corona, varies on a wide range of time scales. Most prominent is the 11-year solar cycle, which is significantly modulated on longer time scales.
Cameron, Robert, Schüssler, Manfred
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