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Related papers: Helicity Observation of Weak and Strong Fields

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Numerical experiments of dynamo action designed to understand the generation of Earth's magnetic field produce different regime branches identified within bifurcation diagrams. Notable are distinct branches where the resultant magnetic…

Geophysics · Physics 2025-08-11 Robert J. Teed , Emmanuel Dormy

The Sun's magnetic field varies in multiple time scales. Observations show that the minimum between cycles 24 and 25 was the second consecutive minimum which was deeper and wider than several earlier minima. Since the active regions…

Solar and Stellar Astrophysics · Physics 2022-01-19 Kiran Jain , Niket Jain , Sushanta C. Tripathy , Mausumi Dikpati

The regular solar observations are operated at Huairou Solar Observing Station (HSOS) since 1987, which make the construction of long-term magnetic field datasets available to understand solar magnetic field and cycles. There exist some…

Solar and Stellar Astrophysics · Physics 2019-02-04 Suo Liu , Ganghua Lin , Xiao Yang , Xiaofan Wang , Jiangtao Su , Yuanyong Deng

Context. Relative field line helicity (RFLH) is a recently developed quantity which can approximate the density of relative magnetic helicity. Aims. This paper aims to determine whether RFLH can be used as an indicator of solar eruptivity.…

Solar and Stellar Astrophysics · Physics 2023-12-22 K. Moraitis , S. Patsourakos , A. Nindos , J. K. Thalmann , É. Pariat

Using the Parker Solar Probe data taken in the inner heliosphere, we investigate the power and spatial anisotropy of magnetic-field spectra at kinetic scales (i.e., around sub-ion scales) in solar wind turbulence in the inner heliosphere.…

Solar and Stellar Astrophysics · Physics 2022-04-20 S. Y. Huang , S. B. Xu , J. Zhang , F. Sahraoui , N. Andres , J. S. He , Z. G. Yuan , X. H. Deng , K. Jiang , Y. Y. Wei , Q. Y. Xiong , Z. Wang , L. Yu , R. T. Lin

Recent years have seen an increased interest in the question of whether the gravitational action of planets could have an influence on the solar dynamo. Without discussing the observational validity of the claimed correlations, we ask for a…

Solar and Stellar Astrophysics · Physics 2016-09-21 F. Stefani , A. Giesecke , N. Weber , T. Weier

Kinetic helicity is a fundamental characteristics of astrophysical turbulent flows. It is not only responsible for the generation of large-scale magnetic fields in the Sun, stars, and spiral galaxies, but it also affects turbulent diffusion…

Fluid Dynamics · Physics 2025-05-15 Igor Rogachevskii , Nathan Kleeorin , Axel Brandenburg

The topology and dynamics of the three-dimensional magnetic field in the solar atmosphere govern various solar eruptive phenomena and activities, such as flares, coronal mass ejections, and filaments/prominences. We have to observe and…

Solar and Stellar Astrophysics · Physics 2017-06-20 Yang Guo , Xin Cheng , M. D. Ding

Understanding the in situ amplification of large scale magnetic fields in turbulent astrophysical rotators has been a core subject of dynamo theory. When turbulent velocities are helical, large scale dynamos that substantially amplify…

Fluid Dynamics · Physics 2012-06-22 Jonathan Pietarila Graham , Eric G. Blackman , Pablo D. Mininni , Annick Pouquet

The work is devoted to the study of periodic structures in the magnetic field of the photosphere. The polarity of the Sun's magnetic fields shows cyclicity with periods of 1-3 years, which is possibly due to quasi-biennial variations that…

Solar and Stellar Astrophysics · Physics 2025-07-08 Elena Vernova , Marta Tyasto , Dmitrii Baranov

We present calculations of helicity based on our solar dynamo model and show that the results are consistent with observational data.

Astrophysics · Physics 2009-11-10 Arnab Rai Choudhuri , Piyali Chatterjee , Dibyendu Nandy

Magnetic fields dominate most solar activities, there exist direct relations between solar flare and the distributions of magnetic field, and also its corresponding magnetic energy. In this paper, the statistical results about the…

Solar and Stellar Astrophysics · Physics 2019-02-03 Suo Liu

For groups of photospheric magnetic fields differing in strength the time averaged synoptic maps were obtained on the basis of the National Solar Observatory Kitt Peak data (1976-2003). The latitudinal profiles of magnetic field fluxes were…

Solar and Stellar Astrophysics · Physics 2018-03-21 Elena Vernova , Marta Tyasto , Dmitrii Baranov

We have carried out a statistical study of the average orientation of the magnetic field in solar filaments with respect to their axes for more than 400 samples, based on data taken with daily full-Sun, full-Stokes spectropolarimetric…

Solar and Stellar Astrophysics · Physics 2020-07-29 Yoichiro Hanaoka , Takashi Sakurai

The great success of Helioseismology resides in the remarkable progress achieved in the understanding of the structure and dynamics of the solar interior. This success mainly relies on the ability to conceive, implement, and operate…

Solar and Stellar Astrophysics · Physics 2018-02-05 P. L. Palle , T. Appourchaux , J. Christensen-Dalsgaard , R. A. Garcia

We study Doppler velocity measurements at multiple heights in the solar atmosphere using a set of six filtergrams obtained by the Helioseismic magnetic Imager on board the Solar Dynamics Observatory. There are clear and significant phase…

Solar and Stellar Astrophysics · Physics 2014-01-15 Kaori Nagashima , Laurent Gizon , Aaron Birch , Björn Löptien , Sebastien Couvidat , Bernhard Fleck

Magnetic helicity is conserved under ideal magnetohydrodynamics (MHD) and quasi-conserved even under a resistive process. The standard definition for magnetic helicity cannot be applied directly to an open magnetic field in a volume,…

Solar and Stellar Astrophysics · Physics 2020-05-27 Kai E. Yang , Michael S. Wheatland , Stuart A. Gilchrist

The existence of a cosmological magnetic field could be revealed by the effects of non-trivial helicity on large scales. We evaluate a CP odd statistic, $Q$, using gamma ray data obtained from Fermi satellite observations at high galactic…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-12 Hiroyuki Tashiro , Wenlei Chen , Francesc Ferrer , Tanmay Vachaspati

The magnetic chirality in solar atmosphere has been studied based on the soft X-ray and magnetic field observations. It is found that some of large-scale twisted soft X-ray loop systems occur for several months in the solar atmosphere,…

Solar and Stellar Astrophysics · Physics 2015-05-19 Hongqi Zhang , Shangbin Yang , Yu Gao , Jiangtao Su , D. D. Sokoloff , K. Kuzanyan

A new model has been proposed for magnetic field determination at different distances from the Sun during different solar cycle phases. The model depends on the observed large-scale non-polar photospheric magnetic fields and that measured…

Solar and Stellar Astrophysics · Physics 2018-08-08 Irina A. Bilenko
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