Related papers: Magnetic fields around late-type stars using water…
In the context of the MiMeS survey of magnetism in massive stars, 85 classical Be stars were observed in circular polarization with the aim of detecting magnetic fields at their surfaces. No direct evidence of such fields is found, in…
(abridged) The role of magnetic field in the shaping of Planetary Nebulae (PNe), either directly or indirectly after being enhanced by binary interaction, has long been a topic of debate. Large scale magnetic fields around pre-PNe have been…
Weak magnetic fields have recently been detected in a number of A-type stars, including Vega and Sirius. At the same time, space photometry observations of A- and late B-type stars from Kepler and TESS have highlighted the existence of…
Context: The role of magnetic fields during high-mass star formation is a matter of fierce debate, yet only a few direct probes of magnetic field strengths are available. Aims: The magnetic field is detected in a number of massive…
Recent asteroseismic analyses have revealed the presence of strong (B $\gtrsim 10^5$ G) magnetic fields in the cores of many red giant stars. Here, we examine the implications of these results for the evolution of stellar magnetic fields,…
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…
Zeeman-Doppler imaging studies have revealed the complexity of the large-scale magnetic fields of accreting pre-main-sequence stars. All have multipolar magnetic fields with the octupole component being the dominant field mode for many of…
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,…
The role of magnetic fields during the protostellar phase of high-mass star-formation is a debated topic. In particular, it is still unclear how magnetic fields influence the formation and dynamic of disks and outflows. Most current…
We have observed the OH (1720 MHz) line in five galactic SNRs with the VLA to measure their magnetic field strengths using the Zeeman effect. We detected all 12 of the bright ($S_{\nu} > 200$ mJy) OH (1720 MHz) masers previously detected by…
RSG stars are very massive cool evolved stars. Recently, a weak magnetic field was measured at the surface of $\alpha$ Ori and this is so far the only M-type supergiant for which a direct detection of a surface magnetic field has been…
We have observed six high-mass star-forming regions in the 2 Pi 3/2, J = 7/2 lines of OH using the GBT in order to investigate whether the magnetic field, and hence the density, measured in absorption differs from that implied by maser…
We analyze full-polarization VLBA data of ground-state, main-line OH masers in 18 massive star-forming regions previously presented in a companion paper. The OH masers often arise in the shocked neutral gas surrounding ultracompact Hii…
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…
General solutions of the maser polarization problem are presented for arbitrary absorption coefficients. The results are used to calculate polarization for masers permeated by magnetic fields with arbitrary values of \xB, the ratio of…
IRAS20126+4104 is a well studied B0.5 protostar that is surrounded by a ~1000 au Keplerian disk and is where a large-scale outflow originates. Both 6.7-GHz CH3OH masers and 22-GHz H2O masers have been detected toward this young stellar…
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…
Planets orbiting young, solar-type stars are embedded in a more energetic environment than that of the solar neighbourhood. They experience harsher conditions due to enhanced stellar magnetic activity and wind shaping the secular evolution…
We present MERLIN maps of the 22-GHz H2O masers around four low-mass late-type stars (IK Tau U Ori, RT Vir and U Her), made with an angular resolution of ~ 15 milliarcsec and a velocity resolution of 0.1 km s-1. The H2O masers are found in…
Magnetic fields play a role in almost all stages of stellar evolution. Most low-mass stars, including the Sun, show surface fields that are generated by dynamo processes in their convective envelopes. Intermediate-mass stars do not have…