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Related papers: Estimating electric current densities in solar act…

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The efficient release of magnetic energy in astrophysical plasmas, such as during solar flares, can in principle be achieved through magnetic diffusion, at a rate determined by the associated electric field. However, attempts at measuring…

Current sheet is believed to be the region of energy dissipation via magnetic reconnection in solar flares. However, its properties, for example, the dynamic process, have not been fully understood. Here we report a current sheet in a solar…

Solar and Stellar Astrophysics · Physics 2018-02-07 Y. Li , J. C. Xue , M. D. Ding , X. Cheng , Y. Su , L. Feng , J. Hong , H. Li , W. Q. Gan

Using time-sequence vector magnetic field observation from \textit{Helioseismic and Magnetic Imager}, we examined the connection of non-neutralized currents and the observed activity in 20 solar active-regions (ARs). The net current in a…

Solar and Stellar Astrophysics · Physics 2019-05-01 P. Vemareddy

We consider tubular nanowires with a polygonal cross-section. In this geometry the lowest energy states are separated in two sets, one of corner and one of side-localized states, respectively. The presence of an external magnetic field…

We determine magnetic fields from the photosphere to the upper chromosphere combining data from the Hinode satellite and the CLASP2.1 sounding rocket experiment. CLASP2.1 provided polarization profiles of the Mg~{|sc ii} $h$ and $k$ lines,…

The solar active region (AR) 12192 was one of the most flare productive region of solar cycle 24, which produced many X-class flares; the most energetic being an X3.1 flare on October 24, 2014 at 21:10 UT. Customarily, such events are…

Solar and Stellar Astrophysics · Physics 2019-01-30 A. Prasad , R. Bhattacharyya , Q. Hu , S. S. Nayak , Sanjay Kumar

A rigorous mathematical proof is given of a class of vector identities that provide a way to separate an arbitrary vector field (over a linear space) into the sum of a radial (i.e., pointing toward the radial unit vector) vector field,…

Classical Physics · Physics 2007-05-23 M. Bornatici , O. Maj

Observations of quiet Sun from the Solar Optical Telescope/Spectro-Polarimeter (SOT/SP) aboard the Hinode spacecraft would reveal the magnetic characters of the solar photosphere. By making use of the deep mode observations of three quiet…

Astrophysics · Physics 2008-12-18 Chunlan Jin , Jingxiu Wang , Meng Zhao

Coronal heating through the explosive release of magnetic energy remains an open problem in solar physics. Recent hydrodynamical models attempt an investigation by placing swarms of 'nanoflares' at random sites and times in modeled…

Solar and Stellar Astrophysics · Physics 2016-11-30 K. Moraitis , A. Toutountzi , H. Isliker , M. Georgoulis , L. Vlahos , G. Chintzoglou

We compute for the first time magnetic helicity and energy spectra of the solar active region NOAA 11158 during 11-15 February 2011 at 20^o southern heliographic latitude using observational photospheric vector magnetograms. We adopt the…

Solar and Stellar Astrophysics · Physics 2014-03-25 Hongqi Zhang , Axel Brandenburg , D. D. Sokoloff

The coupling of Jupiter's magnetosphere and ionosphere plays a vital role in creating its auroral emissions. The strength of these emissions is dependent on the difference in speed of the rotational flows within Jupiter's high-latitude…

Earth and Planetary Astrophysics · Physics 2012-02-20 J. N. Yates , N. Achilleos , P. Guio

High-resolution observations show the fine structure of the global equilibrium magnetic field configuration in solar atmosphere to be essentially different from that assumed in the traditional 'potential + force-free' field scenarios. The…

Solar and Stellar Astrophysics · Physics 2012-05-01 L. A. Pustil'nik , N. R. Ikhsanov , N. G. Beskrovnaya

A few years before the Hinode space telescope was launched, an investigation based on the Hanle effect in atomic and molecular lines indicated that the bulk of the quiet solar photosphere is significantly magnetized, due to the ubiquitous…

Solar and Stellar Astrophysics · Physics 2015-06-12 Nataliya Shchukina , Javier Trujillo Bueno

Vortex-type motions have been measured by tracking bright points in high-resolution observations of the solar photosphere. These small-scale motions are thought to be determinant in the evolution of magnetic footpoints and their interaction…

Solar and Stellar Astrophysics · Physics 2015-05-18 L. Balmaceda , S. Vargas Domínguez , J. Palacios , I. Cabello , V. Domingo

Violent solar flares and coronal mass ejections (CMEs) are magnetic phenomena. However, how magnetic fields reconnecting in the flare differ from non-flaring magnetic fields remains unclear owing to the lack of studies of the flare magnetic…

Solar and Stellar Astrophysics · Physics 2022-02-23 Maria D. Kazachenko , Benjamin J. Lynch , Antonia Savcheva , Xudong Sun , Brian T. Welsch

The observed solar photospheric magnetic fields and Doppler velocities are frequently used to quantify the Poynting flux and helicity flux. Multiple methods have been developed for this purpose, but their estimates of the Poynting flux and…

Solar and Stellar Astrophysics · Physics 2026-04-20 Jiayi Liu , Xudong Sun , Peter W. Schuck , Lars K. S. Daldorff

We have recently developed the capability to make solar vector (Stokes IQUV) magnetograms using the infrared line of MgI at 12.32 microns. On 24 April 2001, we obtained a vector magnetic map of solar active region NOAA 9433, fortuitously…

Astrophysics · Physics 2009-11-07 Donald E. Jennings , Drake Deming , George McCabe , Pedro Sada , Thomas Moran

This paper considers the probability density and current distributions generated by a point-like, isotropic source of monoenergetic charges embedded into a uniform magnetic field environment. Electron sources of this kind have been realized…

Quantum Physics · Physics 2012-09-04 Christian Bracher , Arnulfo Gonzalez

Helicity measures complexity in the field. Magnetic helicity is given by a volume integral over the scalar product of magnetic field {\bf B} and its vector potential {\bf A}. A direct computation of magnetic helicity in the solar atmosphere…

Solar and Stellar Astrophysics · Physics 2015-05-20 Sanjiv Kumar Tiwari

The recent downward revision of solar photospheric abundances of Oxygen and other heavy elements has resulted in serious discrepancies between solar models and solar structure as determined through helioseismology. In this work we…

Astrophysics · Physics 2009-11-11 H. M. Antia , Sarbani Basu