Compact binary millisecond pulsars with main-sequence donors, often referred to as "redbacks," constitute the long-sought link between low-mass X-ray binaries...
X-ray variability of 104 active galactic nuclei. XMM-Newton power-spectrum density profiles
Context. Active galactic nuclei (AGN), powered by accretion onto supermassive black holes (SMBHs), are thought to be scaled up versions of Galactic black hole X...
X-ray, radio, and infrared observations of the 'rapid burster' /MXB 1730-335/ during 1979 and 1980
The paper reports partially simultaneous observations of the 'rapid burster' (MXB 1730-335) at X-ray, infrared, and radio wavelengths, covering several hundred...
X-ray-selected broad absorption line quasi-stellar objects
We study a sample of six X-ray-selected broad absorption line (BAL) quasi-stellar objects (QSOs) from the XMM-Newton Wide Angle Survey. All six objects are...
X-shooter Observations of Main-sequence Stars in the Globular Cluster NGC 2808: First Chemical Tagging of a He-normal and a He-rich Dwarf
We present the first chemical composition study of two unevolved stars in the globular cluster NGC 2808, obtained with the X-shooter spectrograph at VLT. NGC...
X-Shooting ULLYSES: Massive stars at low metallicity. II. DR1: Advanced optical data products for the Magellanic Clouds
Context. The XShootU project aims to obtain ground-based optical to near-infrared spectroscopy of all targets observed by the Hubble Space Telescope (HST) under...
X-Shooting ULLYSES: Massive stars at low metallicity. III. Terminal wind speeds of ULLYSES massive stars
Context. The winds of massive stars have a significant impact on stellar evolution and on the surrounding medium. The maximum speed reached by these outflows...
X-Shooting ULLYSES: Massive stars at low metallicity: IV. Spectral analysis methods and exemplary results for O stars
Context. The spectral analysis of hot, massive stars is a fundamental astrophysical method of determining their intrinsic properties and feedback. With their...