相关论文: Zeeman split lines in CP stars: a discovery of low…
Almost three decades ago, Mathys (1990) demonstrated the importance of studying Ap stars showing resolved Zeeman split Fe II 6147.7 and 6149.2 lines. Such Zeeman split lines can be seen in stars whose projected rotational velocity is…
High-dispersion, archival spectra of magnetic Ap stars with resolved Zeeman components in Stokes I are used to derive a simple relation that can be utilised to estimate the mean surface field strengths of stars with v sin i > 10 km/s. For…
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…
Context. A lot of effort has been put into the detection and determination of stellar magnetic fields using the spectral signal obtained from the combination of hundreds or thousands of individual lines, an approach known as multi-line…
Magnetic fields are an important ingredient to cool star physics, and there is great interest in measuring fields and their geometry in order to understand stellar dynamos and their influence on star formation and stellar evolution. During…
Context. Recent high angular resolution polarimetric continuum observations of circumstellar disks provide new insights into their magnetic field. However, direct constraints are limited to the plane of sky component of the magnetic field.…
Magnetic fields in cool stars are ubiquitous but can still be challenging to characterize due to their complexity and relatively low strength. The polarization signature amplitudes are proportional to the field strength, and current studies…
Magnetic fields are regarded as a crucial element for our understanding of stellar physics. They can be studied with a variety of methods which provide complementary - and sometimes contradictory - information about the structure, strength…
Late-type stars in general possess complicated magnetic surface fields which makes their detection and in particular their modeling and reconstruction challenging. In this work we present a new Zeeman-Doppler imaging code which is…
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…
New magnetic Ap stars with split Zeeman components are presented. These stars were discovered from observations with the FEROS spectrograph at the ESO 2.2-m telescope. Fifteen new magnetic stars are analysed here. Several stars with very…
We present preliminary results from a programme aimed at acquiring linear spectropolarimetry of magnetic A and B stars. Linear polarization in the spectral lines of these objects is due to the Zeeman effect, and should provide detailed new…
Stellar magnetic dynamos are driven by rotation, rapidly rotating stars produce stronger magnetic fields than slowly rotating stars do. The Zeeman effect is the most important indicator of magnetic fields, but Zeeman broadening must be…
We present our analysis aimed at inferring average magnetic fields in slowly-rotating solar-like stars. Using the spectral line inversion code SPINOR, we perform high-accuracy line profile fitting and investigate whether Zeeman broadening…
When using a recently developed method of Doppler-Zeeman mapping (Vasilchenko et al., 1996) for analysis of a real star and real observational data, we are confronted with limitations due to the model simplifications and unavoidable errors…
Magnetic fields are ubiquitous in active cool stars but they are in general complex and weak. Current Zeeman Doppler imaging (ZDI) studies of cool star magnetic fields chiefly employ circular polarization observations because linear…
Fraction of hot stars posses strong magnetic fields that channel their radiatively driven outflows. We study the influence of line splitting in the magnetic field (Zeeman effect) on the wind properties. We use our own global wind code with…
By studying young magnetically active late-type stars, i.e. analogues to the young Sun, one can draw conclusions on the evolution of the solar dynamo. We determine the topology of the surface magnetic field and study the relation between…
Direct measurements of magnetic fields in low-mass stars of spectral class M have become available during the last years. This contribution summarizes the data available on direct magnetic measurements in M dwarfs from Zeeman analysis in…
The influence of a magnetic field on the broadening of spectral lines and transition arrays in complex spectra is investigated. The anomalous absorption or emission Zeeman pattern is a superposition of many profiles with different relative…