Related papers: Early B-type stars with resolved Zeeman split line…
We investigate the detectability of Zeeman broadening in optical Stokes I spectra of slowly rotating sun-like stars. To this end, we apply the LTE spectral line inversion package SPINOR to very-high quality CES data and explore how fit…
Splitting of the strongest absorption lines with a lower-level excitation potential $\chi<$1eV has been detected for the first time in the optical spectra of the post-AGB star V354Lac obtained with a spectral resolution R=60000 at the 6-m…
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…
The evolution of magnetic fields in Ap stars during the main sequence phase is presently mostly unconstrained by observation because of the difficulty of assigning accurate ages to known field Ap stars. We are carrying out a large survey of…
The discovery of the first gravitationally redshifted spectral line from a neutron star (NS) by Cottam, Paerels and Mendez has triggered theoretical studies of the physics of atomic line formation in NS atmospheres. Chang, Bildsten and…
Magnetic fields on hot stars can produce a variety of interesting effects on the velocity, density, and temperature structure in the winds from the stars. The fields can produce a longitudinal dependence of the mass flux, which would lead…
Dynamo action in fully convective stars is a debated issue that also questions our understanding of magnetic field generation in partly convective Sun-like stars. During the past few years, spectropolari- metric observations have…
X-ray emission from stars much more massive than the Sun was discovered only 35 years ago. Such stars drive fast stellar winds where shocks can develop, and it is commonly assumed that the X-rays emerge from the shock-heated plasma. Many…
In our search for new magnetic massive stars we use the strongest indirect indicator of a magnetic field in B stars, which is periodic variability of UV stellar wind lines occurring in a velocity range symmetric around zero. Our aim is to…
We present the results of speckle interferometric observations of 273 magnetic stars most of which are Ap/Bp type. All observations were made at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences.…
In previous works of this series, we have shown that late B- and early A-type stars have genuine bimodal distributions of rotational velocities and that late A-type stars lack slow rotators. The distributions of the surface angular velocity…
We have carried out the first survey of the pulsational line profile variability in rapidly oscillating Ap (roAp) stars. We analysed high signal-to-noise time-series observations of ten sharp-lined roAp stars obtained with the…
Magnetized stars exhibit periodic variations of their longitudinal global magnetic fields, $B_e$, owing to rotation. Here, we present the second catalog of averaged stellar magnetic rotational phase curves and their parameters derived from…
Isolated neutron stars are higly magnetized, fast rotating end points of stellar evolution. They are now becoming directly observable through X-ray astronomy, owing to their high surface temperatures. In particular, features in their X-ray…
We study how rotation affects observable amplitudes of high-order g- and mixed r/g-modes and examine prospects for their detection and identification. Our formalism, which is described in some detail, relies on a nonadiabatic generalization…
Magnetic Doppler imaging from four Stokes parameter observations has uncovered a new level of complexity of stellar magnetic fields previously not known. This new information is of interest to the evolution and structure of magnetic fields…
Context. Knowing the rotation rates and masses of white dwarf stars is an important step towards characterising the angular momentum transport mechanism in their progenitors, and coupling the cores of red giants to their envelopes. However,…
We examine 4-yr almost continuous Kepler photometry of 115 B stars. We find that the light curves of 39 percent of these stars are simply described by a low-frequency sinusoid and its harmonic, usually with variable amplitudes, which we…
Significant progress has been made recently in our understanding of the structure of stellar magnetic fields, thanks to advances in detection methods such as Zeeman-Doppler Imaging. The extrapolation of this surface magnetic field into the…
We re-discuss 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. We confirm our previous results obtained…