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Using Chandra/LETG Spectra to Probe Stellar Coronae

Published online by Cambridge University Press:  26 May 2016

Gaitee A. J. Hussain ,
Nancy Brickhouse ,
A. K. Dupree ,
Adriaan A. van Ballegooijen ,
Andrew Collier Cameron ,
Moira Jardine  and
Jean-Francois Donati
Gaitee A. J. Hussain
Affiliation:
ESTEC, ESA, P.O. Box 299, 2200 AG, Noordwijk, The Netherlands
Nancy Brickhouse
Affiliation:
Harvard Smithsonian CfA, 60 Garden St, Cambridge MA02138, USA
A. K. Dupree
Affiliation:
Harvard Smithsonian CfA, 60 Garden St, Cambridge MA02138, USA
Adriaan A. van Ballegooijen
Affiliation:
Harvard Smithsonian CfA, 60 Garden St, Cambridge MA02138, USA
Andrew Collier Cameron
Affiliation:
School of Physics & Astronomy, Univ. of St Andrews, Fife, UK
Moira Jardine
Affiliation:
School of Physics & Astronomy, Univ. of St Andrews, Fife, UK
Jean-Francois Donati
Affiliation:
Laboratoire d'Astrophysique, Observ. Midi-Pyrénées, Toulouse, France

Abstract

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We probe the relationship between surface magnetic fields and the X-ray emitting corona in the rapidly rotating star, AB Dor. Circularly polarised spectra have been inverted to produce a surface (photospheric) magnetic field map. This surface map has been extrapolated to model AB Dor's coronal field topology and X-ray light curve. Chandra/LETG light curves of AB Dor from the same epoch show intrinsic variability at the 30% level. Period analysis indicates a fraction of this is due to rotational modulation. We measure velocity shifts in emission line centroids as a function of Prot and find evidence of rotational modulation (max. vel. ∼ 40 ± 13km s—1). This modulation may indicate the presence of a localised X-ray emitting region at mid-to-high latitudes.

Type
Part 6: Low Mass Stellar Magnetic Activity and Evolution
Information
Symposium - International Astronomical Union , Volume 219: Stars as Suns : Activity, Evolution and Planets , 2004 , pp. 301 - 305
Copyright
Copyright © Astronomical Society of the Pacific 2004 

References

Brickhouse, N.S., Dupree, A.K. & Young, P.R. 2001, ApJ 562, L75.Google Scholar
Collier Cameron, A., Jardine, M.M. & Donati, J.-F. 2002, in ASP Conf. Proc. 277, eds. Favata, F. & Drake, J.J. (San Francisco: ASP) 397.Google Scholar
Donati, J.-F., et al. 1999, MNRAS, 302, 437.Google Scholar
Drake, J.J., et al. 2000, ApJ, 545, 1074.CrossRefGoogle Scholar
Hussain, G.A.J. et al. 2002, ApJ, 575, 1078.Google Scholar
Kürster, M. et al. 1997, A&A, 320, 831.Google Scholar
Jardine, M. et al. 2001, MNRAS, 324, 201.Google Scholar
Maggio, A., et al. 2000, A&A, 356, 627.Google Scholar
McIvor, T. et al. 2003, MNRAS, 345, 601.CrossRefGoogle Scholar
Sanz-Forcada, J., Brickhouse, N.S., & Dupree, A.K. 2003, ApJS, 145, 147.Google Scholar
Schmitt, J.H.M.M. & Favata, F. 1999, Nature 401, 44.Google Scholar
Schmitt, J.H.M.M., Ness, J.-U. & Franco, G. 2003, A&A.Google Scholar
Semel, M. 1989, A&A, 225, 456.Google Scholar