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Related papers: Flux emergence in a magnetized convection zone

200 papers

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 address a primary question regarding the physical mechanism that triggers the energy release and initiates the onset of eruptions in the magnetar magnetosphere. A self-consistent stationary, axisymmetric model of the magnetar…

Solar and Stellar Astrophysics · Physics 2015-06-11 Cong Yu

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

Kinematic dynamo in incompressible isotropic turbulent flows with high magnetic Prandtl number is considered. The approach interpreting an arbitrary magnetic field distribution as a superposition of localized perturbations (blobs) is…

Fluid Dynamics · Physics 2023-10-26 A. S. Il'yn , A. V. Kopyev , V. A. Sirota , K. P. Zybin

We investigate the emergence of a large-scale magnetic field. This field is dynamo-generated by turbulence driven with a helical forcing function. Twisted arcade-like field structures are found to emerge in the exterior above the turbulence…

Solar and Stellar Astrophysics · Physics 2011-08-31 Jörn Warnecke , Axel Brandenburg

As well known, magnetic fields in space are distributed very inhomogeneously. Some-times field distributions have forms of filaments with high magnetic field values. As many ob-servations show, such a filamentation takes place in convective…

Solar and Stellar Astrophysics · Physics 2024-03-03 Evgeny A. Kuznetsov , Evgeny A. Mikhailov

The magnetic fields in the solar corona are generally neither force-free nor axisymmetric and have complex dynamics that are difficult to characterize. Here we simulate the topological evolution of solar coronal magnetic field lines (MFLs)…

Solar and Stellar Astrophysics · Physics 2017-05-09 A. Prasad , R. Bhattacharyya , Sanjay Kumar

It is widely believed that magnetic flux ropes are the key structure of solar eruptions; however, their observable counterparts are not clear yet. We study a flare associated with flux rope eruption in a comprehensive radiative…

Solar and Stellar Astrophysics · Physics 2022-07-20 Can Wang , Feng Chen , Mingde Ding , Zekun Lu

Several studies have correlated observations of impulsive solar activity -- flares and coronal mass ejections (CMEs) -- with the amount of magnetic flux near strong-field polarity inversion lines (PILs) in active regions' photospheric…

Astrophysics · Physics 2007-10-03 B. T. Welsch , Y. Li

We investigate an intensification mechanism for the magnetic field near the base of the solar convection zone that does not rely on differential rotation. Such mechanism in addition to differential rotation has been suggested by studies of…

Solar and Stellar Astrophysics · Physics 2015-06-11 H. Hotta , M. Rempel , T. Yokoyama

$\delta$-sunspots, with highly complex magnetic structures, are very productive in energetic eruptive events, such as X-class flares and homologous eruptions. We here study the formation of such complex magnetic structures by numerical…

Solar and Stellar Astrophysics · Physics 2015-06-17 Fang Fang , Yuhong Fan

The magnetic configuration hosting prominences and their surrounding coro- nal structure is a key research topic in solar physics. Recent theoretical and observational studies strongly suggest that a helical magnetic flux rope is an es-…

Solar and Stellar Astrophysics · Physics 2015-06-18 Chun Xia , Rony Keppens , Yang Guo

We carry out numerical simulations of the surface evolution of bipolar magnetic regions (BMRs) and magnetic spots on stars, which have radii and surface rotational shears of AB Doradus, the Sun, and the HR 1099 primary. The surface flux…

Astrophysics · Physics 2009-11-11 Emre Isik , Manfred Schuessler , Sami K. Solanki

Solar eruptions are the most powerful drivers of space weather. To understand their cause and nature, it is crucial to know how the coronal magnetic field evolves before eruption. Here we study the formation process of a relatively…

Solar and Stellar Astrophysics · Physics 2020-03-25 Wen He , Chaowei Jiang , Peng Zou , Aiying Duan , Xueshang Feng , Pingbing Zuo , Yi Wang

Stars form in dense cores of magnetized molecular clouds. If the magnetic flux threading the cores is dragged into the stars, the stellar field would be orders of magnitude stronger than observed. This well-known "magnetic flux problem"…

Solar and Stellar Astrophysics · Physics 2015-05-28 Bo Zhao , Zhi-Yun Li , Fumitaka Nakamura , Ruben Krasnopolsky , Hsien Shang

Convection in the liquid outer core of the Earth is driven by thermal and chemical perturbations. The main purpose of this study is to examine the impact of double-diffusive convection on magnetic field generation by means of 3D global…

Geophysics · Physics 2021-05-12 Théo Tassin , Thomas Gastine , Alexandre Fournier

We study numerically large-scale magnetic field evolution and its enhancement in gaseous disks of spiral galaxies. We consider a set of models with the various spiral pattern parameters and the initial magnetic field strength with taking…

Astrophysics of Galaxies · Physics 2018-01-31 S. A. Khoperskov , S. S. Khrapov

Observations of magnetically active close binaries with orbital periods of a few days reveal the existence of starspots at preferred longitudes (with respect to the direction of the companion star). We numerically investigate the non-linear…

Astrophysics · Physics 2009-11-07 V. Holzwarth , M. Schuessler

Formed through magnetic field shearing and reconnection in the solar corona, magnetic flux ropes are structures of twisted magnetic field, threaded along an axis. Their evolution and potential eruption are of great importance for space…

Solar and Stellar Astrophysics · Physics 2017-09-13 Chris Lowder , Anthony Yeates

We present magnetohydrodynamic simulation of the evolution from quasi-equilibrium to onset of eruption of a twisted, prominence-forming coronal magnetic flux rope underlying a corona streamer. The flux rope is built up by an imposed flux…

Solar and Stellar Astrophysics · Physics 2019-05-21 Yuhong Fan , Tie Liu