0000000001062602

AUTHOR

M. Jardine

showing 3 related works from this author

Testing the Ability of Field Extrapolation Models to Predict the X-ray Emission Properties of Pre-Main Sequence Stars

2010

By extrapolating from observationally derived magnetic surface maps, obtained through Zeeman-Doppler imaging, models of stellar magnetospheres can be constructed. By assuming that the plasma trapped along the closed field lines is in hydrostatic equilibrium, coronal X-ray emission properties, such as the global X-ray emission measure and the amount of rotational modulation of X-ray emission, can be predicted. For pre-main sequence magnetospheres the analysis can be extended to incorporate accretion flows, and predict the amount of softer X-ray emission from accretion spots that would be observed. I will detail the preliminary results of an ambitious multi-wavelength, multi-observing site, a…

Settore FIS/05 - Astronomia E Astrofisicastellar activitymagnetic fieldstellar coronae
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Modeling X-ray emission from stellar coronae

2008

By extrapolating from observationally derived surface magnetograms of low-mass stars we construct models of their coronal magnetic fields and compare the 3D field geometry with axial multipoles. AB Dor, which has a radiative core, has a very complex field, whereas V374 Peg, which is completely convective, has a simple dipolar field. We calculate global X-ray emission measures assuming that the plasma trapped along the coronal loops is in hydrostatic equilibrium and compare the differences between assuming isothermal coronae, or by considering a loop temperature profiles. Our preliminary results suggest that the non-isothermal model works well for the complex field of AB Dor, but not for the…

ConvectionPhysicsopacity and line formation Magnetic and electric fieldField (physics)Astrophysics (astro-ph)FOS: Physical sciencesCoronal loopAstrophysicsPlasmapolarization of starlightAstrophysicsMagnetic fieldlaw.inventionStarsSettore FIS/05 - Astronomia E Astrofisicaradiative transferlawX-ray emission spectra and fluorescence Stellar atmospheresRadiative transferAstrophysics::Solar and Stellar AstrophysicsHydrostatic equilibrium
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Modeling X-ray Emission From The Coronae Of Low Mass Stars

2009

By extrapolating from observationally derived surface magnetograms of low-mass stars we construct models of their coronal magnetic fields and compare the 3D field geometries with axial multipoles. AB Dor, which has a radiative core, has a very complex field, whereas V374 Peg, which is completely convective, has a simple dipolar field. We calculate global X-ray emission measures assuming that the plasma trapped along the coronal loops is in hydrostatic equilibrium and compare the differences between assuming isothermal coronae, or by considering loop temperature profiles. Our preliminary results suggest that the non-isothermal model works well for the complex field of AB Dor, but not for the…

Settore FIS/05 - Astronomia E AstrofisicaStellar coronaeAstrophysics
researchProduct