Related papers: Investigating the pre-main sequence magnetic chemi…
Only eleven O-type stars have been confirmed to possess large-scale organized magnetic fields. The presence of a -600G longitudinal magnetic field in the O9.7V star HD54879 with a lower limit of the dipole strength of ~2kG, was discovered a…
Observational evidence for strong magnetic fields throughout the envelopes of evolved stars is increasing. Many of the instruments coming on line in the near-future will be able to make further contributions to this field. Specifically,…
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…
The magnetic field of CPD -57 3509 was recently detected in the framework of the BOB (B fields in OB stars) collaboration. We acquired low-resolution spectropolarimetric observations of CPD -57 3509 with FORS2 and high-resolution UVES…
A longitudinal magnetic field with a strength of 5.2kG was recently detected in CPD -62 2124, which has a fractional main-sequence lifetime of about 60%. Strongly magnetic early-B type chemically peculiar stars in an advanced evolutionary…
Approximately 10% of massive OBA main-sequence (MS) and pre-MS stars harbour strong, large-scale magnetic fields. At the same time there is a dearth of magnetic stars in close binaries. A process generating strong magnetic fields only in…
Massive B-type stars with strong magnetic fields and fast rotation are very rare and provide a mystery for theories of both star formation and magnetic field evolution. Only two such stars, called sigma Ori E analogs, were previously known.…
The stars of the middle main sequence have relatively quiescent outer layers, and unusual chemical abundance patterns may develop in their atmospheres. The presence of chemical peculiarities reveal the action of such subsurface phenomena as…
Studies of the magnetic characteristics of massive stars have recently received significant attention because they are progenitors of highly magnetised compact objects. Stars initially more massive than about 8M_sun leave behind neutron…
The physics of magnetic hot stars and how a large-scale magnetic field affects their interior properties is largely unknown. Few studies have combined high-quality observations and modelling of magnetic pulsating stars, known as…
We report on $H$-band spectra of chemically peculiar Mercury-Manganese (HgMn) stars obtained via the SDSS/APOGEE survey. As opposed to other varieties of chemically peculiar stars such as classical Ap/Bp stars, HgMn stars lack strong…
Our recent discovery of magnetic fields in a small number of Herbig Ae/Be stars has required that we survey a much larger sample of stars. From our FORS1 and ESPaDOnS surveys, we have acquired about 125 observations of some 70 stars in…
We report the discovery of resolved magnetically split lines in two chemically peculiar stars, the SrEuCr star HD 92499 and the Bp SiCr star HD 157751. From FEROS spectra, we have measured a mean magnetic field modulus of 8.5 kG for HD…
According to our understanding of stellar evolution, early-type stars have radiative envelopes and convective cores due to a steep temperature gradient produced by the CNO cycle. Some of these stars (mainly, the subclasses Ap and Bp) have…
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 early-type stars a fossil magnetic field may be generated during the star formation process or be the result of a stellar merger event. Surface magnetic fields are thought to be erased by (sub)surface convection layers, which typically…
Magnetic fields influence the formation and evolution of stars and impact the observed stellar properties. Ap stars (magnetic A-type stars) are a prime example of this. Access to precise and accurate determinations of their stellar…
Six decades and counting, the formation of hot ~20,000-30,000 K Extreme Horizontal Branch (EHB) stars in Galactic Globular Clusters remains one of the most elusive quests in stellar evolutionary theory. Here we report on two discoveries…
Magnetic chemically peculiar stars of the main sequence can present rotational periods as long as many decades. Here we report the results of an observational campaign started in 2001 aimed at establishing these very long periods from the…
We report new spectroscopic observations of the magnetic Of?p star HD 148937 obtained since 2015 that differ qualitatively from its extensive historical record of weak, periodic spectral variations. This remarkable behaviour represents…