相关论文: First results from the LIFE project: discovery of …
We are carrying out a survey of magnetic fields in Ap stars in open clusters in order to obtain the first sample of magnetic upper main sequence stars with precisely known ages. These data will constrain theories of field evolution in these…
Over the last decade, tremendous strides have been achieved in our understanding of magnetism in main sequence hot stars. In particular, the statistical occurrence of their surface magnetism has been established (~10%) and the field origin…
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…
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…
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…
To understand the origin of the magnetic fields in massive stars as well as their impact on stellar internal structure, evolution, and circumstellar environment, within the MiMeS project, we searched for magnetic objects among a large…
We report on the status of our spectropolarimetric observations of massive stars. During the last years, we have discovered magnetic fields in many objects of the upper main sequence, including Be stars, beta Cephei and Slowly Pulsating B…
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…
Magnetic fields have been detected in most if not all types of stars across the Hertzsprung-Russell diagram. Where present, these fields have the potential to significantly impact the evolution of their host stars. Furthermore, they…
Large-scale dipolar surface magnetic fields have been detected in a fraction of OB stars, however only few stellar evolution models of massive stars have considered the impact of these fossil fields. We are performing 1D hydrodynamical…
For several decades we have been cognizant of the presence of magnetic fields in early-type stars, but our understanding of their magnetic properties has recently (over the last decade) expanded due to the new generation of high-resolution…
There is a large change in surface rotation rates of sun-like stars on the pre-main sequence and early main sequence. Since these stars have dynamo driven magnetic fields, this implies a strong evolution of their magnetic properties over…
The "B fields in OB stars" (BOB) collaboration is based on an ESO Large Programme, to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. In the framework of this programme, we carried out…
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…
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…
Massive stars are crucial building blocks of galaxies and the universe, as production sites of heavy elements and as stirring agents and energy providers through stellar winds and supernovae. The field of magnetic massive stars has seen…
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…
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…
We present polarisation measurements of sdB and sdO stars using FORS1 on the VLT. The observations were made as part of a project to determine whether magnetic fields in two super-metal-rich stars can explain their extreme abundance…
To investigate statistically whether magnetic fields in massive stars are ubiquitous or appear in stars with specific spectral classification, certain ages, or in a special environment, we acquired 41 new spectropolarimetric observations…