99 datasets found

Keywords: very long baseline interferometry

Filter Results
  • Revisited jet bending in {gamma}-ray AGNs

    We investigate the hypothesis that {gamma}-ray-quiet active galactic nuclei (AGNs) have a greater tendency for jet bending than {gamma}-ray-loud AGNs, revisiting the analysis of...
  • VLBI monitoring of NGC 4258

    We report a 3yr, 18 epoch, VLBI monitoring study of H_2_O masers in the subparsec, warped, accretion disk within the NGC 4258 AGN. Our immediate goals are to trace the geometry...
  • IC 133 water vapor maser

    We report on the results of a 14yr long VLBI study of proper motions in the IC 133 H_2_O maser source in the galaxy M33.
  • Candidate ICRF flat-spectrum radio sources. III.

    In extending our spectroscopic program, which targets sources drawn from the International Celestial Reference Frame (ICRF) Catalog, we have obtained spectra for ~160 compact,...
  • Second epoch VLBA Calibrator Survey (VCS-II)

    Six very successful Very Long Baseline Array (VLBA) calibrator survey campaigns were run between 1994 and 2007 to build up a large list of compact radio sources with positions...
  • Spectroscopy of 120 emission-line ICRF2 candidates

    Continuing our program of spectroscopic observations of International Celestial Reference Frame (ICRF) sources, we present redshifts for 120 quasars and radio galaxies. Data...
  • Celestial Reference Frame at 24 and 43GHz. II

    We have measured the submilliarcsecond structure of 274 extragalactic sources at 24 and 43 GHz in order to assess their astrometric suitability for use in a high-frequency...
  • Celestial Reference Frame at 24 and 43 GHz

    We present astrometric results for compact extragalactic objects observed with the Very Long Baseline Array at radio frequencies of 24 and 43GHz. Data were obtained from ten...
  • Protostellar winds studied with water masers

    Understanding the launching mechanism of winds and jets remains one of the fundamental challenges in astrophysics. The``Protostellar Outflows at the Earliest Stages'' (POETS)...
  • Gaussian model fit components for 3C345

    The flat-spectrum radio quasar 3C 345 has been showing gamma-ray activity since the mid-2000s along with activity across the electromagnetic spectrum. A gamma-ray burst in 2009...
  • M87* EHT image

    In April 2019, the Event Horizon Telescope (EHT) Collaboration reported the first-ever event-horizon-scale images of a black hole, resolving the central compact radio source in...
  • Mini-cocoon in 3C84 RadioAstron discovery

    We present RadioAstron space-based very long baseline interferometry (VLBI) observations of the nearby radio galaxy 3C84 (NGC1275) at the centre of the Perseus cluster. The...
  • Spectral analysis of M87 jet

    Because of its proximity and the large size of its black hole, M87 is one of the best targets for studying the launching mechanism of active galactic nucleus jets. Currently,...
  • Blazar 3C 454.3 time variability

    Measuring and inferring the key physical parameters of jets in active galactic nuclei (AGN) requires high-resolution very long baseline interferometry (VLBI) observations. Using...
  • Jet collimation in NGC 1052

    With the increased sensitivity and resolution of radio interferometry the study of the collimation and acceleration region of jets in Active Galactic Nuclei(AGN) has come into...
  • A universal pattern in halo magnetic fields

    Magnetic fields in galaxy halos are in general very difficult to observe. Most recently, the Continuum HAlos in Nearby Galaxies - an EVLA Survey (CHANG-ES) collaboration...
  • Jet collimation in NGC 315

    The collimation of relativistic jets in galaxies is a poorly understood process. Detailed radio studies of the jet collimation region have been performed so far in a few...
  • Sub-milliarcsecond imaging of 3C111

    Flares in radio-loud active galactic nuclei (AGNs) are thought to be associated with the injection of fresh plasma into the compact jet base. Such flares are usually strongest...
  • The third realization of the ICRF, ICRF3

    A new realization of the International Celestial Reference Frame (ICRF) is presented based on the work achieved by a working group of the International Astronomical Union (IAU)...
  • S5 0836+710 Ground and Space VLBI images

    Detailed studies of relativistic jets in active galactic nuclei (AGN) require high-fidelity imaging at the highest possible resolution. This can be achieved using very long...
You can also access this registry using the API (see API Docs).