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相关论文: Estimating magnetic filling factors from Zeeman-Do…

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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…

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,…

太阳与恒星天体物理 · 物理学 2024-01-23 Thomas Hackman , Oleg Kochukhov , Mariangela Viviani , Jörn Warnecke , Maarit J. Korpi-Lagg , Jyri J. Lehtinen

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…

太阳与恒星天体物理 · 物理学 2019-01-09 L. T. Lehmann , G. A. J. Hussain , M. M. Jardine , D. H. Mackay , A. A. Vidotto

Global magnetic fields of active solar-like stars are nowadays routinely detected with spectropolarimetric measurements and are mapped with Zeeman-Doppler imaging (ZDI). However, due to the cancellation of opposite field polarities,…

太阳与恒星天体物理 · 物理学 2020-03-25 O. Kochukhov , T. Hackman , J. J. Lehtinen , A. Wehrhahn

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…

太阳与恒星天体物理 · 物理学 2020-05-13 Victor See , Lisa Lehmann , Sean P. Matt , Adam J. Finley

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…

太阳与恒星天体物理 · 物理学 2015-06-18 P. Lang , M. Jardine , J. Morin , J-F. Donati , S. Jeffers , A. A. Vidotto , R. Fares

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…

太阳与恒星天体物理 · 物理学 2020-11-04 Lisa T. Lehmann , Gaitee A. J. Hussain , Aline A. Vidotto , Moira M. Jardine , Duncan H. Mackay

The evolution of the magnetism, winds and rotation of low-mass stars are all linked. One of the most common ways to probe the magnetic properties of low-mass stars is with the Zeeman-Doppler imaging (ZDI) technique. The magnetic properties…

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…

We investigate how the observed large-scale surface magnetic fields of low-mass stars (~0.1 -- 2 Msun), reconstructed through Zeeman-Doppler imaging (ZDI), vary with age t, rotation and X-ray emission. Our sample consists of 104 magnetic…

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…

太阳与恒星天体物理 · 物理学 2025-07-02 Jennifer Rosina Andersson , Oleg Kochukhov , Zheng Zhao , Jens Sjölund

We aim to evaluate how well the variation of small-scale magnetic fields on the stellar surface can be monitored with time-series observations. Further, we aim to establish to what extent the measured total unsigned magnetic field traces…

太阳与恒星天体物理 · 物理学 2026-01-05 A. Hahlin , B. Zaire , C. P. Folsom , K. Al Moulla , A. Lavail

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…

太阳与恒星天体物理 · 物理学 2020-06-11 J. Sebastian Pineda , James R. A. Davenport

Analyses of global magnetic fields in M dwarfs rely on many approximations regarding the derivation of average line profiles from spectropolarimetric data, interpreting them with analytical functions and modelling them using Zeeman Doppler…

太阳与恒星天体物理 · 物理学 2026-01-28 Oleg Kochukhov

The magnetic activity of the Sun changes with the solar cycle. Similar cycles are found in other stars as well, but their details are not known to a similar degree. Characterising stellar magnetic cycles is important for the understanding…

太阳与恒星天体物理 · 物理学 2022-05-11 T. Willamo , J. J. Lehtinen , T. Hackman , M. J. Käpylä , O. Kochukhov , S. V. Jeffers , H. Korhonen , S. C. Marsden

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…

太阳与恒星天体物理 · 物理学 2015-05-18 Colin Johnstone , Moira Jardine , Duncan Mackay

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…

天体物理学 · 物理学 2009-10-31 G. A. J. Hussain , M. Jardine , A. Collier Cameron

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…

太阳与恒星天体物理 · 物理学 2009-11-13 T. A. Carroll , M. Kopf , K. G. Strassmeier , I. Ilyin

We aim to characterise the surface magnetic fields of a sample of 8 T Tauri stars from high-resolution near-IR spectroscopy. Some stars in our sample are known to be magnetic from previous spectroscopic or spectropolarimetric studies. Our…

太阳与恒星天体物理 · 物理学 2019-10-02 Alexis Lavail , Oleg Kochukhov , Gaitee Hussain

The degree to which the formation and evolution of clouds and filaments in the interstellar medium is regulated by magnetic fields remains an open question. Yet the fundamental properties of the fields (strength and 3D morphology) are not…

星系天体物理 · 物理学 2020-10-21 Stefan Reissl , Amelia M. Stutz , Ralf S. Klessen , Daniel Seifried , Stefanie Walch
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