Related papers: A search for magnetic fields in the variable HgMn …
NGC 1624-2 is an O7f?p star with a reported probable polar magnetic field strength $\ge$ 20 kG, which is the strongest magnetic field ever measured in an O-type star. We study the variability of the mean longitudinal magnetic field $\langle…
Context. The first magnetic fields in O- and B-type stars that do not belong to the Bp-star class, have been discovered. The cyclic UV wind-line variability, which has been observed in a significant fraction of early-type stars, is likely…
Several recent spectrophotometric studies failed to detect significant global magnetic fields in late-B HgMn chemically peculiar stars, but some investigations have suggested the presence of strong unstructured or tangled fields in these…
Plaskett's "star" appears to be one of a small number of short-period binary systems known to contain a hot, massive, magnetic star. Building on the 2013 discovery investigation, we combine an extensive spectropolarimetric (Stokes $V$)…
We employ the magnetic and velocity fields from turbulent dynamo simulations to synthesize the polarization of a typical photospheric line. The synthetic Stokes profiles have properties in common with those observed in the quiet Sun. The…
The low-resolution, Cassegrain mounted, FORS spectropolarimeter of the ESO Very Large Telescope is being extensively used for magnetic field surveys. Some of the new discoveries suggest that relatively strong magnetic fields may play an…
In this paper we present an analysis of the first high-resolution full Stokes vector spectropolarimetric observations of the active M dwarf AD Leo. Based on observations collected in 2016 with the ESPaDOnS instrument at CFHT, we derived the…
We aim at a highly sensitive search for weak magnetic fields in main sequence stars of intermediate mass, by scanning classes of stars with no previously reported magnetic members. After detecting a weak magnetic field on the normal,…
Chemically peculiar stars of the mercury-manganese (HgMn) type represent a new class of spotted late-B stars, in which evolving surface chemical inhomogeneities are apparently unrelated to the presence of strong magnetic fields but are…
We report the detection of a magnetic field on Vega through spectropolarimetric observations. We acquired 257 Stokes V, high signal-to-noise and high-resolution echelle spectra during four consecutive nights with the NARVAL…
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…
While several observational investigations have revealed the presence of magnetic fields in the circumstellar envelopes, jets and outflows of post-Asymptotic Giant Branch stars (PAGBs) and planetary nebulae (PNe), none has clearly…
High resolution spectropolarimetric observations of the strongly magnetic, super-slowly rotating rapidly oscillating Ap star HD166473 are used to investigate the implications of the presence of a variable strong magnetic field on the…
We present estimates of magnetic field in a number of AGNs from the Spectropolarimetric atlas of Smith, Young & Robinson (2002) from the observed degrees of linear polarization and the positional angles of spectral lines (H-alpha) (broad…
We use joint observations obtained with the Hinode space observatory and the Interferometric Bidimensional Spectrometer (IBIS) installed at the DST of the NSO/SP to investigate the morphology and dynamics of (a) non-magnetic and (b)…
With FORS1 at the VLT we have tried for the first time to measure the magnetic field variation over the pulsation cycle in six roAp stars to begin the study of how the magnetic field and pulsation interact. For the star HD101065, which has…
Our current knowledge about the stellar magnetic fields relies almost entirely on the circular polarization observations. Very few objects have been observed so far in all four Stokes parameters. The magnetic Ap star HD24712 (DO Eri,…
Mercury-manganese (HgMn) stars have been considered as non-magnetic and non-variable chemically peculiar (CP) stars for a long time. However, recent discoveries of the variability in spectral line profiles have suggested an inhomogeneous…
The polarised spectrum of stellar radiation encodes valuable information on the conditions of stellar atmospheres and the magnetic fields that permeate them. In this paper, we give explicit expressions to estimate the magnetic field vector…
Strong advances in direct evidence of magnetic fields in hot massive stars have been possible thanks to the new generation of high-resolution spectropolarimeters such as ESPaDOnS (on the Canada-France-Hawaii Telescope) or HARPSpol (on the…