English
Related papers

Related papers: Multiresolution analysis of active region magnetic…

200 papers

We study the photospheric magnetic field of ~2000 active regions in solar cycle 23 to search for parameters indicative of energy build-up and subsequent release as a solar flare. We extract three sets of parameters: snapshots in space and…

Solar and Stellar Astrophysics · Physics 2015-07-01 Amani Al-Ghraibah , Laura. E. Boucheron , R. T. James McAteer

A transverse multipole expansion is derived, including the longitudinal components necessarily present in regions of varying magnetic field profile. It can be used for exact numerical orbit following through the fringe field regions of…

Accelerator Physics · Physics 2016-09-08 Yannis Papaphilippou , Jie Wei , Richard Talman

We use helioseismic holography to study the association of shallow flows with solar flare activity in about 250 large sunspot groups observed between 2010 and 2014 with the Helioseismic and Magnetic Imager on the Solar Dynamics Observatory.…

Solar and Stellar Astrophysics · Physics 2016-03-16 D. C. Braun

Magnetic fields are an energetically important component of star-formation galaxies, but it is often difficult to measure their properties from observations. One of the complexities stems from the fact that the magnetic fields, especially…

Astrophysics of Galaxies · Physics 2024-08-09 Amit Seta , Christoph Federrath

Context: The evolution of solar active regions is still not fully understood. The growth and decay of active regions have mostly been studied in case-by-case studies. Aims: Instead of studying the evolution of active regions case by case,…

Solar and Stellar Astrophysics · Physics 2021-03-24 Michal Švanda , M. Sobotka , L. Mravcová , T. Výbošťoková

Magnetic linear dichroism and birefringence in (Ga,Mn)As epitaxial layers is investigated by measuring the polarization plane rotation of reflected linearly polarized light when magnetization lies in the plane of the sample. We report on…

The definition and measurement of magnetic reconnection in three-dimensional magnetic fields with multiple reconnection sites is a challenging problem, particularly in fields lacking null points. We propose a generalization of the familiar…

Plasma Physics · Physics 2015-05-28 A. R. Yeates , G. Hornig

Active regions (ARs) appear in the solar atmosphere as a consequence of the emergence of magnetic flux-ropes (FR). In this study, we use Bayesian methods to analyze line-of-sight magnetograms of emerging ARs. We employ a FR model consisting…

Solar and Stellar Astrophysics · Physics 2024-05-21 Mariano Poisson , Marcelo López Fuentes , Cristina H. Mandrini , Pascal Démoulin , Francisco Grings

Pulsar Wind Nebulae, Blazars, Gamma Ray Bursts and Magnetars all contain regions where the electromagnetic energy density greatly exceeds the plasma energy density. These sources exhibit dramatic flaring activity where the electromagnetic…

High Energy Astrophysical Phenomena · Physics 2017-06-28 Roger Blandford , Yajie Yuan , Masahiro Hoshino , Lorenzo Sironi

From flocks of birds to biomolecular assemblies, systems in which many individual components independently consume energy to perform mechanical work exhibit a wide array of striking behaviors. Methods to quantify the dynamics of these so…

The evolution of nonpotential characteristics of magnetic fields in AR 5747 is presented using Mees Solar Observatory magnetograms taken on Oct. 20, 1989 to Oct. 22, 1989. The active region showed such violent flaring activities during the…

Astrophysics · Physics 2007-05-23 Y. -J. Moon , H. S. Yun , G. S. Choe , Y. D. Park , D. L. Mickey

Recent observations demonstrated that emerging flux regions, which constitute the early stage of solar active regions, consist of emergence of numerous small-scale magnetic elements. They in turn interact, merge, and form mature sunspots.…

Solar and Stellar Astrophysics · Physics 2020-09-16 Jiasheng Wang , Chang Liu , Wenda Cao , Haimin Wang

In this article, we measure the mean magnetic shear from the morphological evolution of flare ribbons, and examine the evolution of flare thermal and non-thermal X-ray emissions during the progress of flare reconnection. We analyze three…

Solar and Stellar Astrophysics · Physics 2022-07-20 Jiong Qiu , Jianxia Cheng

Solar active region (AR) 11283 is a very magnetically complex region and it has produced many eruptions. However, there exists a non-eruptive filament in the plage region just next to an eruptive one in the AR, which gives us an opportunity…

Solar and Stellar Astrophysics · Physics 2016-01-20 Chaowei Jiang , S. T. Wu , Xueshang Feng , Qiang Hu

We make a comparative analysis for two filaments that showed quite different activation in response to the flux emergence within the filament channels. The observations from the Solar Dynamics Observatory (SDO) and Global Oscillation…

Solar and Stellar Astrophysics · Physics 2015-08-06 Ting Li , Jun Zhang , Haisheng Ji

Sources of long wavelength radiation are naturally described by an effective field theory (EFT) which takes the form of a multipole expansion. Its action is given by a derivative expansion where higher order terms are suppressed by powers…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Andreas Ross

Two-dimensional magnetic garnets exhibit complex and fascinating magnetic domain structures, like stripes, labyrinths, cells and mixed states of stripes and cells. These patterns do change in a reversible way when the intensity of an…

Statistical Mechanics · Physics 2009-11-07 J. R. Iglesias , S. Goncalves , O. Nagel , M. Kiwi

The properties of active region nests, which are locations on the Sun with recurring flux emergence, are poorly constrained by observations from Earth alone. ESA's Solar Orbiter now monitors the far side of the Sun for extended periods of…

Solar and Stellar Astrophysics · Physics 2025-05-21 Adam J. Finley , Allan Sacha Brun , Antoine Strugarek , Barbara Perri

Extreme ultraviolet imaging spectroscopic observations often show an increase in line width around the loop-top or above-loop-top (ALT) region of solar flares, suggestive of turbulence. In addition, recent spectroscopic observations found…

Solar and Stellar Astrophysics · Physics 2023-02-08 Kengo Shibata , Shinsuke Takasao , Katharine K. Reeves

Magnetic flux ropes (FRs) are twisted structures appearing on the sun, predominantly in the magnetically concentrated regions. These structures appear as coronal features known as filaments or prominences in H$\alpha$ observations, and as…

Solar and Stellar Astrophysics · Physics 2024-10-04 P. Vemareddy