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Related papers: Modeling the corona of AB Doradus

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We present a technique that combines Zeeman Doppler imaging (ZDI) principles with a potential field mapping prescription in order to gain more information about the surface field topology of rapid rotators. This technique is an improvement…

Astrophysics · Physics 2009-10-31 G. A. J. Hussain , M. Jardine , A. Collier Cameron

We re-analyse spectropolarimetric data of AB Dor taken in 1996 December using a surface imaging code that can model the magnetic field of the star as a non-potential current-carrying magnetic field. We find that a non-potential field needs…

Astrophysics · Physics 2009-11-07 G. A. J. Hussain , A. A. van Ballegooijen , M. Jardine , A. Col lier Cameron

Zeeman-Doppler imaging (ZDI) is used to reconstruct the surface magnetic field of late-type stars from high resolution spectropolarimetric observations. The results are usually described in terms of characteristics of the field topology,…

Solar and Stellar Astrophysics · Physics 2024-01-23 Thomas Hackman , Oleg Kochukhov , Mariangela Viviani , Jörn Warnecke , Maarit J. Korpi-Lagg , Jyri J. Lehtinen

Zeeman-Doppler imaging (ZDI) is used to study the surface magnetic field topology of stars, based on high-resolution spectropolarimetric time series observations. Multiple ZDI inversions have been conducted for the early B-type star tau…

Solar and Stellar Astrophysics · Physics 2025-07-02 Jennifer Rosina Andersson , Oleg Kochukhov , Zheng Zhao , Jens Sjölund

The large-scale magnetic fields of stars can be obtained with the Zeeman-Doppler-Imaging (ZDI) technique, but their interpretation is still challenging as the contribution of the small-scale field or the reliability of the reconstructed…

Solar and Stellar Astrophysics · Physics 2019-01-09 L. T. Lehmann , G. A. J. Hussain , M. M. Jardine , D. H. Mackay , A. A. Vidotto

Zeeman-Doppler Imaging (ZDI) is a powerful inversion method to reconstruct stellar magnetic surface fields. The reconstruction process is usually solved by translating the inverse problem into a regularized least-square or optimization…

Solar and Stellar Astrophysics · Physics 2009-11-13 T. A. Carroll , M. Kopf , K. G. Strassmeier , I. Ilyin

Zeeman Doppler Imaging is a powerful tool for characterizing the strength and topology of stellar magnetic fields. In this research note, we present a new way to visualize the typical results from ZDI for an ensemble of stars, addressing…

Solar and Stellar Astrophysics · Physics 2020-06-11 J. Sebastian Pineda , James R. A. Davenport

Recent advances in spectropolarimetry have allowed the reconstruction of stellar coronal magnetic fields. This uses Zeeman-Doppler magnetograms of the surface magnetic field as a lower boundary condition. The ZDI maps, however, suffer from…

Solar and Stellar Astrophysics · Physics 2015-05-18 Colin Johnstone , Moira Jardine , Duncan Mackay

Polar spots are often observed on rapidly-rotating cool stars, but the nature of the magnetic field in these spots is as yet unknown. While Zeeman-Doppler imaging can provide surface magnetic field maps over much of the observed stellar…

Astrophysics · Physics 2009-11-10 T. McIvor , M. Jardine , A. Collier Cameron , K. Wood , J. -F. Donati

We have used Zeeman-Doppler maps of the surface field of the young, rapid rotator AB Dor (P = 0.514 days) to extrapolate the coronal field, assuming it to be potential. We find that the topology of the large-scale field is very similar in…

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

Magnetic fields of cool stars can be directly investigated through the study of the Zeeman effect on photospheric spectral lines using several approaches. With spectroscopic measurement in unpolarised light, the total magnetic flux averaged…

Zeeman-Doppler imaging is a spectropolarimetric technique that is used to map the large-scale surface magnetic fields of stars. These maps in turn are used to study the structure of the stars' coronae and winds. This method, however, misses…

Solar and Stellar Astrophysics · Physics 2015-06-18 P. Lang , M. Jardine , J. Morin , J-F. Donati , S. Jeffers , A. A. Vidotto , R. Fares

Observations of surface magnetic fields are now within reach for many stellar types thanks to the development of Zeeman-Doppler Imaging. These observations are extremely useful for constraining rotational evolution models of stars, as well…

Solar and Stellar Astrophysics · Physics 2015-09-24 Victor Réville , Allan Sacha Brun , Antoine Strugarek , Sean P. Matt , Jérôme Bouvier , Colin P. Folsom , Pascal Petit

We are reaching the point where spectropolarimetric surveys have run for long enough to reveal solar-like magnetic activity cycles. In this paper we investigate what would be the best strategy to identify solar-like magnetic cycles and ask…

Solar and Stellar Astrophysics · Physics 2020-11-04 Lisa T. Lehmann , Gaitee A. J. Hussain , Aline A. Vidotto , Moira M. Jardine , Duncan H. Mackay

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

We have modelled the X-ray emission from the young rapid rotator AB Doradus (P = 0.514 days) using as a basis Zeeman-Doppler maps of the surface magnetic field. This allows us to reconcile the apparently conflicting observations of a high…

Astrophysics · Physics 2009-11-07 M. Jardine , K. Wood , A. Collier Cameron , J. -F. Donati , D. H. Mackay

Insights on stellar surface large-scale magnetic field topologies are usually drawn by applying Zeeman-Doppler-Imaging (ZDI) to the observed spectropolarimetric time series. However, ZDI requires experience for reliable results to be…

Solar and Stellar Astrophysics · Physics 2022-06-02 L. T. Lehmann , J. -F. Donati

Numerous attempts to estimate the rate at which low-mass stars lose angular momentum over their lifetimes exist in the literature. One approach is to use magnetic maps derived from Zeeman-Doppler imaging (ZDI) in conjunction with so-called…

Solar and Stellar Astrophysics · Physics 2020-05-13 Victor See , Lisa Lehmann , Sean P. Matt , Adam J. Finley

We perform a numerical simulation of the corona of the young, rapidly rotating K0 dwarf AB Doradus using a global MHD model. The model is driven by a surface map of the radial magnetic field constructed using Zeeman-Doppler Imaging. We find…

Solar and Stellar Astrophysics · Physics 2015-05-19 O. Cohen , J. J. Drake , V. L. Kashyap , G. A. J. Hussain , T. I. Gombosi

Magnetic activity and rotation are known to be intimately linked for low-mass stars. Understanding rotation evolution over the stellar lifetime is therefore an important goal within stellar astrophysics. In recent years, there has been…

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