English
Related papers

Related papers: Deriving Potential Coronal Magnetic Fields from Ve…

200 papers

It is a common practice in the solar physics community to test whether or not measured photospheric or chromospheric vector magnetograms are force-free, using the Maxwell stress as a measure. Some previous studies have suggested that…

Solar and Stellar Astrophysics · Physics 2017-01-11 X. M. Zhang , M. Zhang , J. T. Su

Reliable measurements of the solar magnetic field are still restricted to the photosphere, and our present knowledge of the three-dimensional coronal magnetic field is largely based on extrapolation from photospheric magnetogram using…

Solar and Stellar Astrophysics · Physics 2015-06-05 Chaowei Jiang , Xueshang Feng , Changqing Xiang

In this paper the Dirac-Weyl equation on a hyperbolic surface of graphene under magnetic fields is considered. In order to solve this equation analytically for some cases, we will deal with vector potentials symmetric under rotations around…

Mathematical Physics · Physics 2020-05-07 D Demir Kızılırmak , Ş Kuru , J Negro

The Maxwell equations for the electromagnetic potential, supplemented by the Lorenz gauge condition, are decoupled and solved exactly in de Sitter space-time studied in static spherical coordinates. There is no source besides the…

General Relativity and Quantum Cosmology · Physics 2009-12-17 Donato Bini , Giampiero Esposito , Roberto Valentino Montaquila

The Potential Field Source Surface (PFSS) model is the most used approach for extrapolating the global coronal magnetic field, offering efficiency and strong performance at large scales. However, PFSS assumes a potential coronal field, so…

Solar and Stellar Astrophysics · Physics 2026-03-23 C. Antonio , I. Chifu , R. Gafeira , J. J. G. Lima

Active regions (ARs) are typical magnetic structures found in the solar atmosphere. We calculate several magnetohydrostatic (MHS) equilibrium models that include the effect of a finite plasma-$\beta$ and gravity and that are representative…

Solar and Stellar Astrophysics · Physics 2023-03-08 Jaume Terradas , Thomas Neukirch

Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal dynamic phenomena at all scales. We employ STEREO/COR1 data obtained near maximum of solar activity in December 2012 (Carrington…

Solar and Stellar Astrophysics · Physics 2016-04-05 Maxim Kramar , Vladimir Airapetian , Haosheng Lin

Measurements of the interplanetary magnetic field (IMF) over several solar cycles do not agree with computed values of open magnetic flux from potential field extrapolations. The discrepancy becomes greater around solar maximum in each…

Solar and Stellar Astrophysics · Physics 2015-05-19 A. R. Yeates , D. H. Mackay , A. A. van Ballegooijen , J. A. Constable

The Coronal Global Evolutionary Model (CGEM) provides data-driven simulations of the magnetic field in the solar corona to better understand the build-up of magnetic energy that leads to eruptive events. The CGEM project has developed six…

Photospheric electric fields, estimated from sequences of vector magnetic field and Doppler measurements, can be used to estimate the flux of magnetic energy (the Poynting flux) into the corona and as time-dependent boundary conditions for…

Solar and Stellar Astrophysics · Physics 2014-10-13 Maria D. Kazachenko , George H. Fisher , Brian T. Welsch

Relative magnetic helicity is commonly used in solar physics to avoid the well known gauge ambiguity of standard magnetic helicity in magnetically open domains. But its physical interpretation is difficult owing to the invocation of a…

Solar and Stellar Astrophysics · Physics 2026-01-12 Anthony R. Yeates , Gunnar Hornig

In the solar photosphere, many properties of coronal holes (CHs) are not known, especially vector magnetic fields. Using observations from \emph{Hinode}, we investigate vector magnetic fields, current densities and current helicities in two…

Solar and Stellar Astrophysics · Physics 2015-05-20 Shuhong Yang , Jun Zhang , Ting Li , Mingde Ding

Determining the electric field (E-field) distribution on the Sun's photosphere is essential for quantitative studies of how energy flows from the Sun's photosphere, through the corona, and into the heliosphere. This E-field also provides…

Solar and Stellar Astrophysics · Physics 2014-11-20 G. H. Fisher , B. T. Welsch , W. P. Abbett , D. J. Bercik

Parker's coronal braiding and nanoflaring scenario predicts the development of tangential discontinuities and highly misaligned magnetic field lines, as a consequence of random buffeting of their footpoints due to the action of…

Solar and Stellar Astrophysics · Physics 2018-08-17 M. J. Aschwanden , A. A van Ballegooijen

Analyzing electromagnetic fields in complex, multi-material environments presents substantial computational challenges. To address these, we propose a hybrid numerical method that couples discrete exterior calculus (DEC) with surface…

Numerical Analysis · Mathematics 2026-02-09 Amgad Abdrabou , Luis J. Gomez

The chromosphere is a complex solar atmosphere that hosts a variety of transients and transports significant free energy to heat the corona. However, due to the limited sensitivity of polarization measurement and the influence of spectral…

Solar and Stellar Astrophysics · Physics 2026-03-24 Jiasheng Wang , Wenxian Li , Xianyong Bai , Yingzi Sun , Yuanyong Deng , Jiaben Lin

Rapid and stepwise changes of the magnetic field are often observed during flares but cannot be explained by models yet. Using a 45 min sequence of SDO/HMI 135 s fast-cadence vector magnetograms of the X1 flare on 2014-03-29 we construct,…

Solar and Stellar Astrophysics · Physics 2018-10-17 Lucia Kleint , Michael S. Wheatland , Alpha Mastrano , Patrick I. McCauley

The localized spin triplet ground state of a nitrogen vacancy (NV) center in diamond can be used in atomic-scale detection of local magnetic fields. Here we present a technique using these defects in diamond to image fields around magnetic…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 B. J. Maertz , A. P. Wijnheijmer , G. D. Fuchs , M. E. Nowakowski , D. D. Awschalom

We study the evolution of the observed photospheric magnetic field and the modeled global coronal magnetic field during the past 3 1/2 solar activity cycles observed since the mid-1970s. We use synoptic magnetograms and extrapolated…

Solar and Stellar Astrophysics · Physics 2015-06-15 G. J. D. Petrie

Solar magnetic fields are closely related to various physical phenomena on the sun, which can be extrapolated with different models from photospheric magnetograms. However, the Open Flux Problem (OFP), the underestimation of the magnetic…

Solar and Stellar Astrophysics · Physics 2024-05-30 Guanglu Shi , Li Feng , Beili Ying , Shuting Li , Weiqun Gan
‹ Prev 1 4 5 6 7 8 10 Next ›