Related papers: Cosmological and kinematical criteria for the ICRF…
The INTEGRAL satellite has been observing the gamma-ray sky for 15 years and has detected over 900 X-ray sources of various nature. However, more than 200 of these sources still lack precise identification. Our goal is to reveal the nature…
The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) continues to successfully work in orbit after its launch in 2002. The mission provides the deepest ever survey of hard X-ray sources throughout the Galaxy at energies above 20…
We have used the Very Large Array (VLA), linked with the Pie Town Very Long Baseline Array antenna, to determine astrometric positions of 46 radio stars in the International Celestial Reference Frame (ICRF). Positions were obtained in the…
Transient radio signals of astrophysical origin present an avenue for studying the dynamic universe. With the next generation of radio interferometers being planned and built, there is great potential for detecting and studying large…
Variations in scaling behavior in the flux and emissions of distant astronomical sources with respect to their cosmic time are important l phenomena that can provide valuable information about the dynamics within the sources and their…
In order to show the principle viability of a recently proposed relativistic positioning method based on the use of pulsed signals from sources at infinity, we present an application example reconstructing the world-line of an idealized…
Calibration is one of the long-standing problems in optical interferometric measurements, particularly with long baselines which demand stars with angular sizes on the milliarcsecond scale and no detectable companions. While systems of…
We present a catalogue of a large sample of extended radio sources in the SCORPIO field, observed and resolved by the Australia Telescope Compact Array. SCORPIO, a pathfinder project for addressing the early operations of the Australia SKA…
Aims. Construction of a new quasar candidate catalog from the Red-Sequence Cluster Survey 2 (RCS-2), identified solely from photometric information using an automated algorithm suitable for large surveys. The algorithm performance is tested…
We calculate the expected number of strongly lensed radio sources in a sample of 6500 sources observed with the Very Large Array as part of the Cosmic Lens All Sky Survey (CLASS) during the first two sessions of its observations. A…
We present a catalog of Faraday rotation measures (RMs) and redshifts for 4003 extragalactic radio sources detected at 1.4 GHz, derived by identifying optical counterparts and spectroscopic redshifts for linearly polarized radio sources…
The NRAO VLA Sky Survey (NVSS) Rotation Measure (RM) catalogue is invaluable for the study of cosmic magnetism. However, the RM values reported in it can be affected by n$\pi$-ambiguity, resulting in deviations of the reported RM from the…
A catalogue of astrometric (positions, proper motions) and photometric (B, V, R, r', J) data of stars in fields with ICRF objects has been compiled at the Observatory of the National Academy of Sciences of Ukraine and the Kyiv University…
We analyze stellar proper motions in the COSMOS field to assess the presence of bulk motions. At bright magnitudes (G-band 18.5--20.76 AB), we use the proper motions of 1,010 stars in the Gaia DR2 catalog. At the faint end, we computed…
Active Galactic Nuclei (AGNs) observed with the technique of very long baseline interferometry (VLBI) are used as fiducial references on the sky to precisely measure the shape and orientation of the Earth. Their positions form a celestial…
Correlating ether-drift measurements in laboratory and CMB observations in space would confirm the existence of a preferred reference frame. To this end, however, the velocity of light in the interferometers cannot be the same parameter 'c'…
We extend previous works by considering two additional radio frequencies (K band and X/Ka band) with the aim to study the frequency dependence of the source positions and its potential connection with the physical properties of the…
Astrometric noise in excess of parallax and proper motion could be a signature of orbital wobble of individual components in binary star systems. The combination of X-ray selection with astrometric noise can then be a powerful tool for…
Our present understanding of the extragalactic source counts and background radiation at infrared and sub-mm wavelengths is reviewed. Available count data are used to constrain evolutionary models of galaxies and Active Nuclei. The CIRB, on…
The definition of the Galactic coordinate system was announced by the IAU Sub-Commission 33b on behalf of the IAU in 1958. For more than 50 years the definition of the Galactic coordinate system has remained unchanged from this IAU1958…