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Related papers: Helicity Observation of Weak and Strong Fields

200 papers

Periodic oscillations at 338 nHz in the Earth frame are observed at high latitudes in direct Doppler velocity measurements. These oscillations correspond to the $m=1$ high-latitude global mode of inertial oscillation. In this study, we…

Solar and Stellar Astrophysics · Physics 2025-11-12 Stephan G. Heinemann , Zhi-Chao Liang , Laurent Gizon

The observations of magnetic field variations as a signature of flaring activity is one of the main goal in solar physics. Some efforts in the past give apparently no unambiguous observations of changes. We observed that the scaling laws of…

In its first encounter at solar distances as close as r = 0.16AU, Parker Solar Probe (PSP) observed numerous local reversals, or inversions, in the heliospheric magnetic field (HMF), which were accompanied by large spikes in solar wind…

Solar and Stellar Astrophysics · Physics 2021-01-06 Allan R Macneil , Mathew J Owens , Robert T Wicks , Mike Lockwood

Using one-dimensional models, we show that a helical magnetic field with an appropriate sign of helicity can compensate the Faraday depolarization resulting from the superposition of Faraday-rotated polarization planes from a spatially…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-23 Axel Brandenburg , Rodion Stepanov

On the base of the solar magnetic field measurements obtained in Stanford in 1976--2003 the properties of the cyclic evolution of the large-scale magnetic field are investigated. Some regularities are found in longitudinal and latitudinal…

Astrophysics · Physics 2007-05-23 R. N. Ikhsanov , V. G. Ivanov

In this ISSI-supported series of studies on magnetic helicity in the Sun, we systematically implement different magnetic helicity calculation methods on high-quality solar magnetogram observations. We apply finite-volume, discrete flux tube…

Solar and Stellar Astrophysics · Physics 2021-11-24 J. K. Thalmann , M. K. Georgoulis , Y. Liu , E. Pariat , G. Valori , S. Anfinogentov , F. Chen , Y. Guo , K. Moraitis , S. Yang , A. Mastrano

Rotation of the large scale solar magnetic field has a great importance for the understanding of solar dynamic, for the search of longitidinal structure and for the study of solar-terrestrial relations. 30-year long observations taken at…

Solar and Stellar Astrophysics · Physics 2018-02-08 E. A. Gavryuseva

The global magnetic field in the solar corona is known to contain free magnetic energy and magnetic helicity above that of a current-free (potential) state. But the strength of this non-potentiality and its evolution over the solar cycle…

Solar and Stellar Astrophysics · Physics 2024-05-24 Anthony R. Yeates

We determine the effect of intergalactic magnetic fields on the distribution of high energy gamma rays by performing three-dimensional Monte Carlo simulations of the development of gamma-ray-induced electromagnetic cascades in the…

High Energy Astrophysical Phenomena · Physics 2016-10-19 Rafael Alves Batista , Andrey Saveliev , Guenter Sigl , Tanmay Vachaspati

Measurements from the Mount Wilson Observatory (MWO) are used to study the long-term variations of sunspot field strengths from 1920 to 1958. Following a modified approach similar to that in Pevtsov et al. (2011), for each observing week we…

Solar and Stellar Astrophysics · Physics 2013-01-28 Alexei A. Pevtsov , Luca Bertello , Andrey G. Tlatov , Ali Kilcik , Yury A. Nagovitsyn , Edward W. Cliver

The evolution of magnetic fields is studied using simulations of forced helical turbulence with strong imposed shear. After some initial exponential growth, the magnetic field develops a large scale travelling wave pattern. The resulting…

Astrophysics · Physics 2009-10-31 Axel Brandenburg , Alberto Bigazzi , Kandaswamy Subramanian

Long-lived rotational and meridional flows are important ingredients of the solar cycle. Magnetic field images have typically been used to measure these flows on the solar surface by cross-correlating thin longitudinal strips or square…

Solar and Stellar Astrophysics · Physics 2017-02-15 Derek A. Lamb

Magnetic fields correlated on kiloparsec scales are seen in spiral galaxies. Their origin could be due to amplification of a small seed field by a turbulent galactic dynamo. We review the current status of the galactic dynamo, especially…

Astrophysics · Physics 2007-05-23 Kandaswamy Subramanian

Photospheric magnetic fields were studied using the Kitt Peak synoptic maps for 1976-2003. Only strong magnetic fields (B>100 G) of the equatorial region were taken into account. The north-south asymmetry of the magnetic fluxes was…

Solar and Stellar Astrophysics · Physics 2014-05-27 E. S. Vernova , M. I. Tyasto , D. G. Baranov

Based on several magnetic nonpotentiality parameters obtained from the vector photospheric active region magnetograms obtained with the Solar Magnetic Field Telescope at the Huairou Solar Observing Station over two solar cycles, a machine…

Solar and Stellar Astrophysics · Physics 2013-08-29 Xiao Yang , GangHua Lin , HongQi Zhang , XinJie Mao

Using the 135-second cadence of the photospheric vector data provided by the Helioseismic and Magnetic Imager telescope on board the Solar Dynamic Observatory, we examined the time-evolution of magnetic helicity fluxes across the…

Solar and Stellar Astrophysics · Physics 2018-10-17 Yi Bi , Ying D Liu , Yanxiao Liu , Jiayan Yang , Zhe Xu , Kaifan JI

Standard statistical analysis of the magnetic properties of the quiet Sun rely on simple histograms of quantities inferred from maximum-likelihood estimations. Because of the inherent degeneracies, either intrinsic or induced by the noise,…

Solar and Stellar Astrophysics · Physics 2014-12-03 A. Asensio Ramos , M. J. Martínez González

Some common properties of helical magnetic fields in decaying and driven turbulence are discussed. These include mainly the inverse cascade that produces fields on progressively larger scales. Magnetic helicity also restricts the evolution…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

In addition to sunspots, which represent the most easily visualized manifestation of solar magnetism, cutting-edge observations of the solar atmosphere have uncovered a plethora of magnetic flux tubes, down to the resolving power of modern…

Solar and Stellar Astrophysics · Physics 2025-02-27 M. Stangalini , G. Verth , V. Fedun , D. Perrone , M. Berretti , P. Bushby , S. Jafarzadeh , D. B. Jess , F. Giannattasio , P. H. Keys , R. Bruno , F. Berrilli

Thirty-four years of WSO (Wilcox Solar Observatory) and thirteen years of SOHO/MDI (Michelson Doppler Imager on the Solar and Heliospheric Observatory) magnetograms have been studied to measure the east-west inclination angle, indicating…

Solar and Stellar Astrophysics · Physics 2010-03-23 Leyan Lo , Todd Hoeksema , Phil Scherrer