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Related papers: Emerging Flux Simulations and Proto-Active Regions

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Before using 3D MHD simulations of the solar photosphere in the determination of elemental abundances, one has to ensure that the correct amount of magnetic flux is present in the simulations. The presence of magnetic flux modifies the…

Solar and Stellar Astrophysics · Physics 2017-06-28 C. Beck , D. Fabbian , R. Rezaei , K. G. Puschmann

We study the formation of a sunspot penumbra in the active region NOAA11024. We simultaneously observed the Stokes parameters of the photospheric iron lines at 1089.6 nm with the TIP and 617.3 nm with the GFPI spectropolarimeters along with…

Solar and Stellar Astrophysics · Physics 2011-11-15 Reza Rezaei , Nazaret Bello Gonzalez , Rolf Schlichenmaier

Using high-resolution AthenaK simulations of a twisted toroidal flux tube, we study the flux emergence of magnetic structures in the shear layer of a hot massive neutron star typical of a binary neutron star remnant. High-resolution…

High Energy Astrophysical Phenomena · Physics 2026-02-26 Jacob Fields , David Radice , Peter Hammond

It is generally believed that sunspots are the emergent part of magnetic flux tubes in the solar interior. These tubes are created at the base of the convection zone and rise to the surface due to their magnetic buoyancy. The motion of…

Solar and Stellar Astrophysics · Physics 2015-05-14 Franck Plunian , Graeme Sarson , Rodion Stepanov

Evidence of surface magnetism is now observed on an increasing number of cool stars. The detailed manner by which dynamo-generated magnetic fields giving rise to starspots traverse the convection zone still remains unclear. Some insight…

Solar and Stellar Astrophysics · Physics 2017-09-20 Maria A. Weber , Matthew K. Browning , Suzannah Boardman , Joshua Clarke , Samuel Pugsley , Edward Townsend

The current study aims to quantify characteristic features of bipolar flux appearance of solar intranetwork (IN) magnetic elements. To attack such a problem, we use the Narrow-band Filter Imager (NFI) magnetograms from the Solar Optical…

Solar and Stellar Astrophysics · Physics 2012-03-06 Jingxiu Wang , Guiping Zhou , Chunlan Jin , Hui Li

We study the emergence of magnetic flux at very small spatial scales (less than 2 arcsec) in the quiet Sun internetwork. To this aim, a time series of spectropolarimetric maps was taken at disk center using the instrument SP/SOT on board…

We study the evolution of a small-scale emerging flux region (EFR) in the quiet Sun, from its emergence to its decay. We track processes and phenomena across all atmospheric layers, explore their interrelations and compare our findings with…

Solar and Stellar Astrophysics · Physics 2020-01-15 I. Kontogiannis , G. Tsiropoula , K. Tziotziou , C. Gontikakis , C. Kuckein , M. Verma , C. Denker

We present the new results of the two-dimensional numerical experiments on the cross-sectional evolution of a twisted magnetic flux tube rising from the deeper solar convection zone (-20,000 km) to the corona through the surface. The…

Solar and Stellar Astrophysics · Physics 2015-05-28 Shin Toriumi , Takaaki Yokoyama

Recently, there have been some reports of unusually strong photospheric magnetic fields (which can reach values of over 7 kG) inferred from Hinode SOT/SP sunspot observations within penumbral regions. These superstrong penumbral fields are…

Solar and Stellar Astrophysics · Physics 2019-10-30 A. Siu-Tapia , A. Lagg , M. van Noort , M. Rempel , S. K. Solanki

Due to dust grain alignment with magnetic fields, dust polarization observations of far-infrared emission from cold molecular clouds are often used to trace magnetic fields, allowing a probe of the effects of magnetic fields on the star…

We investigate the emergence of magnetic flux in the quiet Sun at very small spatial scales, focusing on the magnetic connection between the photosphere and chromosphere. The observational data consist of spectropolarimetric measurements…

Solar and Stellar Astrophysics · Physics 2009-07-22 M. J. Martinez Gonzalez , L. R. Bellot Rubio

We perform two-dimensional MHD simulations on the solar flux emergence. We set the initial magnetic flux sheet at z=-20,000 km in the convection zone. The flux sheet rises through the convective layer due to the Parker instability, however,…

Solar and Stellar Astrophysics · Physics 2015-05-18 Shin Toriumi , Takaaki Yokoyama

Recent work by Mitra et al. (2014) has shown that in strongly stratified forced two-layer turbulence with helicity and corresponding large-scale dynamo action in the lower layer, a magnetic field occurs in the upper layer in the form of…

Solar and Stellar Astrophysics · Physics 2015-06-03 Sarah Jabbari , Axel Brandenburg , Nathan Kleeorin , Dhrubaditya Mitra , Igor Rogachevskii

On 2016 September 20, the Interface Region Imaging Spectrograph observed an active region during its earliest emerging phase for almost 7 hours. The Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory observed…

Solar and Stellar Astrophysics · Physics 2018-03-14 Hui Tian , Xiaoshuai Zhu , Hardi Peter , Jie Zhao , Tanmoy Samanta , Yajie Chen

We have performed a three-dimensional magnetohydrodynamic simulation to study the emergence of a twisted magnetic flux tube from -20,000 km of the solar convection zone to the corona through the photosphere and the chromosphere. The middle…

Solar and Stellar Astrophysics · Physics 2015-06-03 S. Toriumi , T. Yokoyama

As a large-scale motion on the Sun, the meridional flow plays an important role in determining magnetic structure and strength and solar cycle. However, the meridional flow near the solar poles is still unclear. The Hinode observations show…

Solar and Stellar Astrophysics · Physics 2024-07-29 Shuhong Yang , Jie Jiang , Zifan Wang , Yijun Hou , Chunlan Jin , Qiao Song , Yukun Luo , Ting Li , Jun Zhang , Yuzong Zhang , Guiping Zhou , Yuanyong Deng , Jingxiu Wang

Flux emergence is crucial for the formation of solar active regions and triggering of various eruptions. However, the detailed mechanisms by which flux emergence drives these eruptions remain unclear and require numerical investigation.…

Solar and Stellar Astrophysics · Physics 2025-06-18 Xiaohong Li , Yuhao Zhou , Rony Keppens

We investigate the temporal evolution of magnetic flux emerging within a granule in the quiet-Sun internetwork at disk center. We combined IR spectropolarimetry performed in two Fe I lines at 1565 nm with speckle-reconstructed G-band…

Solar and Stellar Astrophysics · Physics 2017-12-27 P. Gömöry , C. Beck , H. Balthasar , J. Rybák , A. Kucera , J. Koza , H. Wöhl

Here we summarize our recent results of high-resolution computer simulations on the turbulent amplification of weak magnetic seed fields showing that such fields will be exponentially amplified also during the gravitational collapse…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-22 Robi Banerjee , Sharanya Sur , Christoph Federrath , Dominik R. G. Schleicher , Ralf S. Klessen