Related papers: Circumstellar magnetic fields in Herbig Ae stars
We have obtained accurate circular spectropolarimetric observations for a sample of Vega-like and Herbig Ae/Be stars with FORS1 at the VLT in an attempt to detect their magnetic fields. No magnetic field could be diagnosed in any Vega-like…
An extremely weak circularly-polarized signature was recently discovered in spectral lines of the chemically peculiar Am star Sirius A (Petit et al. 2011). This signal was interpreted as a Zeeman signature related to a sub-gauss…
I review ongoing efforts to understand the incidence of magnetism in intermediate-mass stars that are different from the magnetic Ap stars. This includes the search for magnetic fields in chemically peculiar stars of the Am and HgMn types…
In this contribution I review some of the major work that have been undertaken in the last decade to study the magnetic fields in intermediate-mass pre-main sequence stars, with the goal of understanding the origin of the magnetic fields…
The origin of the strong magnetic fields observed in chemically peculiar Ap and Bp stars stars has long been debated. The recent discovery of magnetic fields in the intermediate mass pre-main sequence Herbig Ae and Be stars links them to Ap…
Stellar Magnetism affects all spectral types and exists and varies throughout the evolution of stars. Magnetic fields can affect not only the interior of stars, but also their circumstellar environments. In this chapter, we concentrate on…
Substantial progress has been achieved over the last decade in studies of stellar magnetism due to the improvement of magnetic field measurement methods. We review recent results on the magnetic field characteristics of early B- and O-type…
A small fraction of the population of intermediate-mass and massive stars host strong and stable magnetic fields organised on large scales. These fields are believed to be remnants of star formation. It is however not clear how such fossil…
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 the analysis of the circular polarization, due to Zeeman splitting, of the water masers around a sample of late-type stars to determine the magnetic fields in their circumstellar envelopes. The magnetic field strengths in the…
Over the last decade, large-scale, organized (generally dipolar) magnetic fields with a strength between 0.1 and 20 kG were detected in dozens of OB stars. This contribution reviews the impact of such magnetic fields on the stellar winds of…
In this paper I will discuss new magnetic field diagnostics and instrumentation for an area of astrophysics where magnetic field observations have been difficult - circumstellar material. Such diagnostics would be particularly relevant to…
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 obtained high-resolution, high signal-to-noise UVES and a few lower quality HARPS spectra revealing the presence of resolved magnetically split lines. HD101412 is the first Herbig Ae star for which the rotational Doppler effect was found…
In the context of the ESPaDOnS and Narval spectropolarimetric surveys of Herbig Ae/Be stars, we discovered and then monitored the magnetic field of HD 190073 over more than four years, from 2004 to 2009. Our observations all displayed…
In spite of recent detections of magnetic fields in a number of beta Cephei and slowly pulsating B (SPB) stars, their impact on stellar rotation, pulsations, and element diffusion is not sufficiently studied yet. The reason for this is the…
With only a handful of known magnetic massive stars, there is a troubling deficit in the scope of our knowledge of the influence of magnetic fields on stellar evolution, and almost no empirical basis for understanding how fields modify mass…
For the first time we have directly detected magnetic fields in central stars of planetary nebulae by means of spectro-polarimetry with FORS1 at the VLT. In all four objects of our sample we found kilogauss magnetic fields, in NGC1360 and…
We present a review of observations of the stellar longitudinal (effective) magnetic field ($B_e$) and its properties. This paper also discusses contemporary views on the origin, evolution and structure of $B_e$.
Most of the planetary nebulae (PN) have bipolar or other non-spherically symmetric shapes. The presence of a magnetic field in the central star may be the reason for this lack of symmetry, but observational works published in the literature…