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Related papers: Magnetohydrostatic modelling of stellar coronae

200 papers

We present a novel experiment with the capacity to independently measure both the electron density and the magnetic field of the solar corona. We achieve this through measurement of the excess Faraday rotation due to propagation of the…

Astrophysics · Physics 2009-11-13 S. M. Ord , S. Johnston , J. Sarkissian

Observations suggest a power-law relation between the coronal emission in X-rays, $L_{\rm{X}}$, and the total (unsigned) magnetic flux at the stellar surface, $\Phi$. The physics basis for this relation is poorly understood. We use…

Solar and Stellar Astrophysics · Physics 2021-08-04 J. Zhuleku , J. Warnecke , H. Peter

We investigate the dynamics of a closed corona cartesian reduced magnetohydrodynamic (MHD) model where photospheric vortices twist the coronal magnetic field lines. We consider two corotating or counter-rotating vortices localized at the…

Solar and Stellar Astrophysics · Physics 2019-10-17 A. F. Rappazzo , M. Velli , R. B. Dahlburg , G. Einaudi

With the neutron star rotating under a stationary magnetic field generating unipolar induction, charges are driven to the pulsar surface according to their signs, and are uploaded to the magnetosphere along the magnetic field lines. In the…

High Energy Astrophysical Phenomena · Physics 2021-12-20 K. H. Tsui

In this paper we focus on the construction of stellar outflow models emerging from a polar coronal hole-type region surrounded by a magnetosphere in the equatorial regions during phases of quiescent accretion. The models are based on…

Solar and Stellar Astrophysics · Physics 2016-02-26 P. Todorov , T. Matsakos , V. Cayatte , C. Sauty , J. J. G. Lima , K. Tsinganos

In this paper, we simulate the magnetic flux evolution at different heliocentric distances during two solar-maximum Carrington rotations (CRs) using the time-evolving coronal magnetohydrodynamic (MHD) model COCONUT to investigate the ``open…

We carry out the first time-dependent numerical MagnetoHydroDynamic modeling of an extrasolar planetary system to study the interaction of the stellar magnetic field and wind with the planetary magnetosphere and outflow. We base our model…

Solar and Stellar Astrophysics · Physics 2015-05-27 O. Cohen , V. L. Kashyap , J. J. Drake , I. V. Sokolov , C. Garraffo , T. I. Gombosi

We develop a theoretical model that explains the formation of hot coronae around strongly magnetized neutron stars -- magnetars. The starquakes of a magnetar shear its external magnetic field, which becomes non-potential and is threaded by…

Astrophysics · Physics 2008-11-26 Andrei M. Beloborodov , Christopher Thompson

For main-sequence stars beyond spectral type M5 the characteristics of magnetic activity common to warmer solar-like stars change into the brown-dwarf domain: the surface magnetic field becomes more dipolar and the evolution of the field…

Solar and Stellar Astrophysics · Physics 2011-02-11 C. J. Schrijver

Herschel observation has recently revealed that interstellar molecular clouds consist of many filaments. Polarization observations in optical and infrared wavelengths indicate that the magnetic field often runs perpendicular to the…

Astrophysics of Galaxies · Physics 2015-06-18 Kohji Tomisaka

Context: The stellar wind and the interplanetary magnetic field modify the topology of planetary magnetospheres. Consequently, the hazardous effect of the direct exposition to the stellar wind, for example regarding the integrity of…

Earth and Planetary Astrophysics · Physics 2022-03-07 J. Varela , A. S. Brun , A. Strugarek , V. Reville , P. Zarka , F. Pantellini

We present a model of the magnetosphere around an oscillating neutron star. The electromagnetic fields are numerically solved by modeling electric charge and current induced by the stellar torsional mode, with particular emphasis on…

High Energy Astrophysical Phenomena · Physics 2016-06-21 Yasufumi Kojima , Yugo E. Kato

We study the link between an expanding coronal shock and the energetic particles measured near Earth during the Ground Level Enhancement (GLE) of 17 May 2012. We developed a new technique based on multipoint imaging to triangulate the 3-D…

Using solar wind observation near PSP perihelions as constraints, we have investigated the parameters in various PFSS model methods. It's found that the interplanetary magnetic field extrapolation with source surface height $R_\mathrm{SS} =…

Solar and Stellar Astrophysics · Physics 2023-05-23 Yuechun Song

We present 2D local box simulations of near-surface radiative magneto-convection with prescribed magnetic flux, carried out with the MHD version of the CO5BOLD code for the Sun and a solar-like star with a metal-poor chemical composition…

Solar and Stellar Astrophysics · Physics 2009-11-13 M. Steffen , H. -G. Ludwig , O. Steiner

We present a radiation-magnetohydrodynamics (RMHD) simulation of a magnetic cancellation event. The model is calculated with the Bifrost code and spans from the uppermost convection zone to the corona. The cancellation occurs between the…

Solar and Stellar Astrophysics · Physics 2025-10-24 F. Moreno-Insertis , V. H. Hansteen , D. Nóbrega-Siverio

Active regions (ARs) are typical magnetic structures found in the solar atmosphere. We calculate several magnetohydrostatic (MHS) equilibrium models that include the effect of a finite plasma-$\beta$ and gravity and that are representative…

Solar and Stellar Astrophysics · Physics 2023-03-08 Jaume Terradas , Thomas Neukirch

An analytical and numerical treatment is given of a constrained version of the tectonics model developed by Priest, Heyvaerts, & Title [2002]. We begin with an initial uniform magnetic field ${\bf B} = B_0 \hat{\bf z}$ that is line-tied at…

Solar and Stellar Astrophysics · Physics 2011-09-07 C. S. Ng , A. Bhattacharjee

The magnetised solar wind modulates the Galactic cosmic ray flux in the heliosphere up to rigidities as high as 40 GeV. In this work, we present a new and straightforward extension of the popular, but limited force-field model, thus…

High Energy Astrophysical Phenomena · Physics 2019-12-25 Marco Kuhlen , Philipp Mertsch

M dwarf's atmosphere is expected to be highly magnetized. The magnetic energy can be responsible for heating the stellar chromosphere and corona, and driving the stellar wind. The nonlinear propagation of Alfv\'en wave is the promising…

Solar and Stellar Astrophysics · Physics 2021-09-29 Takahito Sakaue , Kazunari Shibata