Related papers: Transverse motions in CSOs?
The peculiar motion of massive objects across the line of sight imprints a dipolar temperature anisotropy pattern on the cosmic microwave background known as the moving lens effect. This effect provides a unique probe of the transverse…
Emission in the ultraviolet continuum is a salient signature of the hot, massive and consequently short-lived, stellar population that traces recent or ongoing star formation. With the aim of mapping star forming regions and morphologically…
A short overview is given of the status of research on young extragalactic radio sources. We concentrate on Very Long Baseline Interferometric (VLBI), and space-VLBI results obtained with the VLBI Space Observatory Programme (VSOP). In…
We derive the prediction of the standard model of superluminal radio sources for the apparent transverse velocity of a radio source located at redshift z. The apparent velocity of the source is reduced by a factor of 1 + z compared to that…
Symmetric extragalactic radio sources exhibit a baffling array of features - the remarkable symmetry between the two lobes, the emission in the radio frequency range, well collimated jets, core regions emitting blue and ultraviolet light,…
Double lobe radio sources associated with active galactic nuclei represent one of the longest studied groups in radio astronomy. A particular sub-group of double radio sources comprises the compact symmetric objects (CSOs). CSOs are…
Until now it has not been possible to obtain the proper motions of PSR B1849+00 with timing techniques or VLBI imaging given the enhanced interstellar scattering along its line of sight. We present an analysis of archive Very Large Array…
In conjunction with a previous southern-hemisphere work, we present the largest radio survey of jets from massive protostars to date with high-resolution, ($\sim 0.04^{\prime\prime}$) VLA observations towards two subsamples of massive…
Gravitational waves propagate along null geodesics like light rays in the geometrical optics approximation, and they may have a chance to suffer from gravitational lensing by intervening objects, as is the case for electromagnetic waves.…
The kinematics of jets in active galactic nuclei (QSOs, BL Lacs, Radio Galaxies and Empty Field objects) on parsec scales is being studied with Very Long Baseline Array observations at 15 GHz of a sample of more than 170 radio sources. More…
It is expected that the European Space Agency mission Gaia will make possible to determine coordinates in the optical domain of more than 500000 quasars. In 2006, a radio astrometry project was launched with the overall goal to make…
The tremendous growth of positioning technologies and GPS enabled devices has produced huge volumes of tracking data during the recent years. This source of information constitutes a rich input for data analytics processes, either offline…
We describe the dynamical evolution of hot spots velocity, pressure and mass density in radio loud active galactic nuclei (AGNs), taking proper account of (1) the conservations of the mass, momentum, and kinetic energy flux of the unshocked…
We present results of multifrequency polarimetric VLBA observations of 34 compact radio sources. The observations are part of a large survey undertaken to identify CSOs Observed in the Northern Sky (COINS). Based on VLBI continuum surveys…
Context. Central compact objects (CCOs) are a peculiar class of neutron stars, primarily encountered close to the center of young supernova remnants (SNRs) and characterized by thermal X-ray emission. Aims. Our goal is to perform a…
Using a large set of optically detected hotspots in powerful extragalactic double radio sources, we examine the basic question of whether the detection of optical synchrotron radiation requires in-situ acceleration of relativistic electrons…
We wish to perform a statistical study of the location and motion of individual 22 GHz water maser cloudlets, characterized by sizes that are within a few au, with respect to the radio thermal emission from young stellar objects (YSO). For…
A parallax method to determine transverse velocity in a gravitationally lensed system is described. Using the annual motion of the Earth around the Sun allows us to probe the local structure of the magnification map that, under certain…
Compact Symmetric Objects (CSOs) are a distinct category of jetted active galactic nuclei whose high-energy emission is not well understood. We examined the X-ray characteristics of 17 bona fide CSOs using observations from Chandra,…
Accurate alignment of the radio and optical celestial reference frames requires detailed understanding of physical factors that may cause offsets between the positions of the same object measured in different spectral bands. Opacity in…