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Related papers: Coronal magnetic field evolution over the cycle 24

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We developed a {\sl coronal non-linear force-free field (COR-NLFFF)} forward-fitting code that fits an approximate {\sl non-linear force-free field (NLFFF)} solution to the observed geometry of automatically traced coronal loops. In…

Solar and Stellar Astrophysics · Physics 2015-06-18 Markus J. Aschwanden , Xudong Sun , Yang Liu

This white paper advocates the importance of multi-height measurements of the vector magnetic field in the solar atmosphere. As briefly described in this document, these measurements are critical for addressing some of the most fundamental…

Instrumentation and Methods for Astrophysics · Physics 2022-09-13 L. Bertello , N. Arge , A. G. De Wijn , S. Gosain , C. Henney , K. D. Leka , J. Linker , Y. Liu , J. Luhmann , P. J. Macniece , G. Petrie , A. Pevtsov , A. A. Pevtsov

Coronal and chromospheric magnetic fields are derived from polarization and spectral observations of the thermal free-free emission using the Nobeyama Radioheliograph (NoRH). In magnetized plasma, the ordinary and extraordinary modes of…

Solar and Stellar Astrophysics · Physics 2015-06-16 Kazumasa Iwai , Kiyoto Shibasaki

Coronal hole spatial-temporal evolution is studied and comparison made with that of the solar global magnetic field in cycles 21-23 (1976-2012). The latitude-longitude distribution dynamics of coronal holes and the regularities in the…

Solar and Stellar Astrophysics · Physics 2018-05-25 I. A. Bilenko , K. S. Tavastsherna

We describe a newly developed code for the extrapolation of nonlinear force-free coronal magnetic fields in spherical coordinates. The program uses measured vector magnetograms on the solar photosphere as input and solves the force-free…

Astrophysics · Physics 2008-11-26 Thomas Wiegelmann

The hemispheric pattern of solar filaments is considered in the context of the global magnetic field of the solar corona. In recent work Mackay and van Ballegooijen have shown how, for a pair of interacting magnetic bipoles, the observed…

Astrophysics · Physics 2009-11-13 A. R. Yeates , D. H. Mackay , A. A. van Ballegooijen

The photospheric response to solar flares, also known as coronal back reaction, is often observed as sudden flare-induced changes in vector magnetic field and sunspot motions. However, it remains obscure whether evolving flare ribbons, the…

Solar and Stellar Astrophysics · Physics 2018-12-19 Chang Liu , Wenda Cao , Jongchul Chae , Kwangsu Ahn , Debi Prasad Choudhary , Jeongwoo Lee , Rui Liu , Na Deng , Jiasheng Wang , Haimin Wang

The coronal magnetic field directly or indirectly affects a majority of the phenomena studied in space physics. It provides energy for coronal heating, controls the release of coronal mass ejections (CMEs), and drives heliospheric and…

Solar and Stellar Astrophysics · Physics 2016-04-13 Shaela I. Jones , Joseph M. Davila , Vadim M. Uritsky

In the solar corona, magnetic flux rope is believed to be a fundamental structure accounts for magnetic free energy storage and solar eruptions. Up to the present, the extrapolation of magnetic field from boundary data is the primary way to…

Solar and Stellar Astrophysics · Physics 2016-01-20 Chaowei Jiang , Xueshang Feng

The Sun is a highly dynamic environment that exhibits dynamic behavior on many different timescales. In particular, coronal holes exhibit temporal and spatial variability. Signatures of these coronal dynamics are inherited by the coronal…

Magnetic fields generated in the Sun's interior by the solar dynamo mechanism drive solar activity over a range of time-scales. While space-based observations of the Sun's corona exist only for few decades, direct sunspot observations exist…

Solar and Stellar Astrophysics · Physics 2023-07-03 Soumyaranjan Dash , Dibyendu Nandy , Ilya Usoskin

Using the polar vector magnetic field data observed by Hinode from 2012 to 2021, we study the long-term variations of the magnetic flux, the flux proportion of different polarities, and the magnetic inclination with respect to the local…

Solar and Stellar Astrophysics · Physics 2025-09-25 Shuhong Yang , Chunlan Jin , Qiao Song , Yuzong Zhang , Yin Li , Yijun Hou , Ting Li , Guiping Zhou , Yuanyong Deng , Jingxiu Wang

For a better understanding of magnetic field in the solar corona and dynamic activities such as flares and coronal mass ejections, it is crucial to measure the time-evolving coronal field and accurately estimate the magnetic energy.…

Solar and Stellar Astrophysics · Physics 2020-02-26 Shin Toriumi , Shinsuke Takasao , Mark C. M. Cheung , Chaowei Jiang , Yang Guo , Keiji Hayashi , Satoshi Inoue

Recent studies of the heliospheric magnetic field (HMF) have detected interesting, systematic hemispherical and longitudinal asymmetries which have a profound significance for the understanding of solar magnetic fields. The in situ HMF…

Astrophysics · Physics 2009-11-10 K. Mursula , T. Hiltula

Most of the intracyclic variability in the large-scale solar magnetic field comes from the equatorial dipole component of the solar magnetic field. The equatorial dipole component is highly sensitive to the longitude distribution of the…

Solar and Stellar Astrophysics · Physics 2026-03-09 Ismo Tähtinen , Timo Asikainen , Kalevi Mursula

We simulate the buoyant rise of a magnetic flux rope from the solar convection zone into the corona to better understand the energetic coupling of the solar interior to the corona. The magnetohydrodynamic model addresses the physics of…

Solar and Stellar Astrophysics · Physics 2015-06-03 Fang Fang , Ward Manchester , William P. Abbett , Bart van der Holst

Current models of the solar wind must approximate (or ignore) the small-scale dynamics within the solar atmosphere, however these are likely important in shaping the emerging wave-turbulence spectrum and ultimately heating/accelerating the…

Solar and Stellar Astrophysics · Physics 2022-09-28 Adam J. Finley , Sacha A. Brun , Mats Carlsson , Mikolaj Szydlarski , Viggo Hansteen , Munehito Shoda

We report observations of a steady 20 year decline of solar photospheric fields at latitudes $\geq$45${^{o}}$ starting from $\sim$1995. This prolonged and continuing decline, combined with the fact that Cycle 24 is already past its peak,…

Solar and Stellar Astrophysics · Physics 2015-09-16 P. Janardhan , Susanta Kumar Bisoi , S. Ananthakrishnan , M. Tokumaru , K. Fujiki , L. Jose , R. Sridharan

In solving the solar coronal heating problem, it is crucial to comprehend the mechanisms by which energy is conveyed from the photosphere to the corona. Recently, magnetic tornadoes, characterized as coherent, rotating magnetic field…

Solar and Stellar Astrophysics · Physics 2023-05-31 Hidetaka Kuniyoshi , Munehito Shoda , Haruhisa Iijima , Takaaki Yokoyama

Time-evolving MHD coronal models deliver more realistic results than traditional quasi-steady-state models. The fully implicit time-evolving coronal model COCONUT performs efficiently enough for real-time coronal simulations during solar…