Absolute kinematics of radio source components in the complete S5 polar cap sample: III. First wide-field high-precision astrometry at 15.4GHz

• We report on the first wide-field, high-precision astrometric analysis of the 13 extragalactic radio sources of the complete S5 polar cap sample at 15.4 GHz. We describe new algorithms developed to enable the use of differenced phase delays in wide-field astrometric observations and discuss the impact of using differenced phase delays on the precision of the wide-field astrometric analysis. From this global fit, we obtained estimates of the relative source positions with precisions ranging from 14 to 200 as at 15.4 GHz, depending on the angular separation of the sources (from ∼1.6 to ∼20.8 degrees). These precisions are ∼10 times higher than the achievable precisions using the phase-reference mapping technique. © 2008 ESO.

Ämnesord

NATURVETENSKAP  -- Fysik -- Astronomi, astrofysik och kosmologi (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Astronomy, Astrophysics and Cosmology (hsv//eng)

Nyckelord

Radio continuum: general

Galaxies: quasars: general

Galaxies: BL Lacertae objects: general

Astrometry

Techniques: interferometric

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)