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Related papers: The Coronal Structure of AB Doradus

200 papers

We have developed a data-driven magnetohydrodynamic (MHD) model of the global solar corona which uses characteristically-consistent boundary conditions (BCs) at the inner boundary. Our global solar corona model can be driven by different…

Solar and Stellar Astrophysics · Physics 2017-06-28 Mehmet Sarp Yalim , Nikolai Pogorelov , Yang Liu

The concentration of magnetic flux near the poles of rapidly rotating cool stars has been recently proposed as an alternative mechanism to dynamo saturation in order to explain the saturation of angular momentum loss. In this work we study…

Astrophysics · Physics 2007-07-25 A. Aibéo , J. M. Ferreira , J. J. G. Lima

EUV images of Comet Lovejoy (C/2011 W3) from the AIA show striations related to the magnetic field structure in both open and closed magnetic regions. The brightness contrast implies coronal density contrasts of at least a factor of 6…

Solar and Stellar Astrophysics · Physics 2015-06-19 J. C. Raymond , P. I. McCauley , S. R. Cranmer , C. Downs

We describe, test, and apply a technique to incorporate full-sun, surface flux evolution into an MHD model of the global solar corona. Requiring only maps of the evolving surface flux, our method is similar to that of Lionello et al.…

Solar and Stellar Astrophysics · Physics 2023-10-12 Roberto Lionello , Cooper Downs , Emily I. Mason , Jon A. Linker , Ronald M. Caplan , Pete Riley , Viacheslav S. Titov , Marc L. DeRosa

We study the connections between the sun's convection zone and the evolution of the solar wind and corona. We let the magnetic fields generated by a 2.5D axisymmetric kinematic dynamo code (STELEM) evolve in a 2.5D axisymmetric coronal…

Solar and Stellar Astrophysics · Physics 2015-05-28 Rui F. Pinto , Allan Sacha Brun , Laurène Jouve , Roland Grappin

From Zeeman Doppler images of the young, rapidly-rotating K0 dwarf AB Doradus, we have created a potential approximation to the observed radial magnetic field and have evolved it over 30 days due to the observed surface differential…

Astrophysics · Physics 2009-11-07 G. R. Pointer , M. Jardine , A. Collier Cameron , J. -F. Donati

Observations of stellar rotation show that low-mass stars lose angular momentum during the main sequence. We simulate the winds of Sun-like stars with a range of rotation rates, covering the fast and slow magneto-rotator regimes, including…

We use three-dimensional magnetohydrodynamical (MHD) simulations to study the formation of a corona above an initially weakly magnetized, isothermal accretion disk. We also describe a modification to time-explicit numerical algorithms for…

Astrophysics · Physics 2009-10-31 K. A. Miller , J. M. Stone

Identifying the heating mechanisms of the solar corona and the driving mechanisms of solar wind are key challenges in understanding solar physics. A full three-dimensional compressible magnetohydrodynamic (MHD) simulation was conducted to…

Solar and Stellar Astrophysics · Physics 2020-11-25 Takuma Matsumoto

Oscillations are abundant in the solar corona. Coronal loop oscillations are typically studied using highly idealised models of magnetic flux tubes. In order to improve our understanding of coronal oscillations, it is necessary to consider…

Solar and Stellar Astrophysics · Physics 2023-08-02 P. Kohutova , P. Antolin , M. Szydlarski , M. Carlsson

We aim to reproduce the structure of the corona above a solar active region as seen in the extreme ultraviolet (EUV) using a three-dimensional magnetohydrodynamic (3D MHD) model. The 3D MHD data-driven model solves the induction equation…

Solar and Stellar Astrophysics · Physics 2019-04-30 Jörn Warnecke , Hardi Peter

Significant progress has been made recently in our understanding of the structure of stellar magnetic fields, thanks to advances in detection methods such as Zeeman-Doppler Imaging. The extrapolation of this surface magnetic field into the…

Solar and Stellar Astrophysics · Physics 2015-05-19 Doris Arzoumanian , Moira Jardine , Jean-François Donati , Julien Morin , Colin Johnstone

A 3D model intermediate between cellular automata (CA) models and the reduced magnetohydrodynamic (RMHD) equations is presented to simulate solar impulsive events generated along a coronal magnetic loop. The model consists of a set of…

Astrophysics · Physics 2007-05-23 E. Buchlin , V. Aletti , S. Galtier , M. Velli , G. Einaudi , J. -C. Vial

Stellar coronae are believed to be the main birthplace of various stellar magnetic activities. However, the structures and properties of stellar coronae remain poorly understood. Using the Space Weather Modelling Framework with the…

The propagation and the evolution of Alfvenic pulses in the solar coronal arcades is investigated by means of MHD numerical simulations. Significant transverse oscillations in coronal loops, triggered by nearby flare events, are often…

Astrophysics · Physics 2009-11-10 Luca Del Zanna , Eveline Schaekens , Marco Velli

The structure of a star's coronal magnetic field is a fundamental property that governs the high-energy emission from the hot coronal gas and the loss of mass and angular momentum in the stellar wind. It is, however, extremely difficult to…

Solar and Stellar Astrophysics · Physics 2020-01-08 M. Jardine , A. Collier Cameron , J. -F. Donati , G. A. J. Hussain

A fine analysis of spectral line widths and Doppler shifts employing Fourier transform and cross-correlation techniques has been applied to Chandra HETG spectra obtained in 1999 October of the rapidly rotating young star AB Doradus in order…

Solar and Stellar Astrophysics · Physics 2015-06-23 Jeremy J. Drake , Sun Mi Chung , Vinay L. Kashyap , David Garcia-Alvarez

Core convection and dynamo activity deep within rotating A-type stars of 2 solar masses are studied with 3--D nonlinear simulations. Our modeling considers the inner 30% by radius of such stars, thus capturing within a spherical domain the…

Astrophysics · Physics 2008-11-26 Allan Sacha Brun , Matthew K. Browning , Juri Toomre

Recent asteroseismic studies have revealed that the convective core of $\gamma$ Doradus stars rotates faster than their radiative interior. We study the development of differential rotation near the convective core to test angular momentum…

Solar and Stellar Astrophysics · Physics 2024-01-12 Facundo Moyano , Patrick Eggenberger , Sébastien Salmon

The rapid rotation (P=0.44 d) of the M dwarf V374Peg (M4) along with its intense magnetic field point toward magneto-centrifugal acceleration of a coronal wind. In this work, we investigate the structure of the wind of V374Peg by means of…

Solar and Stellar Astrophysics · Physics 2011-01-07 A. A. Vidotto , M. Jardine , M. Opher , J. -F. Donati , T. I. Gombosi