相关论文: Discovery of magnetic fields in hot subdwarfs

We present initial results of a project to measure mean longitudinal magnetic fields in a group of sdB/OB/O stars. The project was inspired by the discovery of three super-metal-rich sdOB stars, each having metals (e.g. Ti, V) enhanced by…

Detection of magnetic fields has been reported in several sdO and sdB stars. Recent literature has cast doubts on the reliability of most of these detections. We revisit data previously published in the literature, and we present new…

We have carried out a re-analysis of polarimetric data of central stars of planetary nebulae, hot subdwarfs, and white dwarfs taken with FORS1 (FOcal Reducer and low dispersion Spectrograph) on the VLT (Very Large Telescope), and added a…

The presence of magnetic fields in O-type stars has been suspected for a long time. The discovery of such fields would explain a wide range of well documented enigmatic phenomena in massive stars, in particular cyclical wind variability,…

Magnetic fields can play an important role in stellar evolution. Among white dwarfs, the most common stellar remnant, the fraction of magnetic systems is more than 20 per cent. The origin of magnetic fields in white dwarfs, which show…

About 5% of upper main sequence stars are permeated by a strong magnetic field, the origin of which is still matter of debate. With this work we provide observational material to study how magnetic fields change with the evolution of stars…

To properly understand the physics of upper main sequence stars it is particularly important to identify the origin of their magnetic fields. Recently, we confirmed that magnetic fields appear in Ap stars of mass below 3 M_sun only if they…

Our knowledge of the magnetism in white dwarfs is based on an observational dataset that is biased in favour of stars with very strong magnetic fields. Most of the field measurements available in the literature have a relatively low…

The presence of magnetic fields at the surfaces of many massive stars has been suspected for decades, to explain the observed properties and activity of OB stars. However, very few genuine high-mass stars had been identified as magnetic…

We rediscuss the evolutionary state of upper main sequence magnetic stars using a sample of Ap and Bp stars with accurate Hipparcos parallaxes and definitely determined longitudinal magnetic fields. FORS1 at the VLT in spectropolarimetric…

Despite their rarity, massive stars dominate the ecology of galaxies via their strong, radiatively-driven winds throughout their lives and as supernovae in their deaths. However, their evolution and subsequent impact on their environment…

Theories on the origin of magnetic fields in massive stars remain poorly developed, because the properties of their magnetic field as function of stellar parameters could not yet be investigated. To investigate whether magnetic fields in…

I review our current knowledge of magnetic fields in stars more massive than around 1.5 Msun, in particular their nature and origin. This includes the strong magnetic fields found in a subset of the population and the fossil field theory…

To properly understand the physics of Ap and Bp stars it is particularly important to identify the origin of their magnetic fields. For that, an accurate knowledge of the evolutionary state of stars that have a measured magnetic field is an…

Magnetic fields have been detected on stars across the H-R diagram and substellar objects either directly by their effect on the formation of spectral lines, or through the activity phenomena they power which can be observed across a large…

It is now well-known that the surface magnetic fields observed in cool, lower-mass stars on the main sequence (MS) are generated by dynamos operating in their convective envelopes. However, higher-mass stars (above 1.5 Msun) pass their MS…

About 10% of hot stars host a fossil magnetic field on the pre-main sequence and main sequence. However, the first magnetic evolved hot stars have been discovered only recently. An observing program has been set up to find more such…

The presence of magnetic fields in O-type stars has been suspected for a long time. The discovery of such fields would explain a wide range of well documented enigmatic phenomena in massive stars, in particular cyclical wind variability, H…

Strong, globally-organized magnetic fields are found for a small fraction of O, B, and A stars. At the same time, many theoretical and indirect observational studies suggested ubiquitous presence of weak localized magnetic fields at the…

The sample of white dwarfs included in the local 20 pc volume documents, fairly accurately, the total production of white dwarfs over roughly 10 Gyr of stellar evolution in this part of the Milky Way Galaxy. In this sample, we have been…