Search Publications
The Polstar UV spectropolarimetry mission
Ignace, R.; Scowen, P.
The Polstar small explorer concept is for an ultraviolet (UV) spectropolarimetry space telescope mission with a focus on massive star astrophysics. The instrument waveband will be from 115 nm to 286 nm for spectroscopy, and from 122 nm to 286 nm for polarimetry. All four Stokes parameters, I, Q, U, and V , will be measured at a resolving power of …
X-rays, clumping and wind structures
Ignace, Richard; Oskinova, Lidia; Hamann, Wolf-Rainer +1 more
X-ray emission is ubiquitous among massive stars. In the last decade, X-ray observations revolutionized our perception of stellar winds but opened a Pandora's box of urgent problems. X-rays penetrating stellar winds suffer mainly continuum absorption, which greatly simplifies the radiative transfer treatment. The small and large scale structures i…
The peculiar O9.5V star BD+53°2790, the massive counterpart to the X-ray binary system 4U 2206+54
Blay, Pere; Reglero, Víctor
The X-ray binary system 4U 2206+54 hides many mysteries. Among them, the surprising behavior of both of its co components: the O9.5 dwarf star BD+53°2790 and a slowly rotating neutron star. BD+53°2790 misled the astronomers, exhibiting characteristics reminiscent of Be stars. However, a deeper spectral analysis and more intense monitoring revealed…