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http://dx.doi.org/10.5303/JKAS.2015.48.5.277

MEASURING THE CORE SHIFT EFFECT IN AGN JETS WITH THE EXTENDED KOREAN VLBI NETWORK  

JUNG, TAEHYUN (Korea Astronomy and Space Science Institute)
DODSON, RICHARD (International Centre for Radio Astronomy Research, M468, The University of Western Australia)
HAN, SEOG-TAE (Korea Astronomy and Space Science Institute)
RIOJA, MARIA J. (International Centre for Radio Astronomy Research, M468, The University of Western Australia)
BYUN, DO-YOUNG (Korea Astronomy and Space Science Institute)
HONMA, MAREKI (Mizsawa VLBI Observatory, National Astronomical Observatory of Japan, Japan)
STEVENS, JAMIE (Australia Telescope National Facility, CSIRO, Australia)
VICENTE, PABLO DE (Observatorio Astronomico Nacional (IGN))
SOHN, BONG WON (Korea Astronomy and Space Science Institute)
Publication Information
Journal of The Korean Astronomical Society / v.48, no.5, 2015 , pp. 277-284 More about this Journal
Abstract
We present our efforts for extending the simultaneous multi-frequency receiver system of the Korean Very Long Baseline Interferometry (VLBI) Network (KVN) to global baselines in order to measure the frequency-dependent position shifts in Active Galactic Nuclei (AGN) jets, the so called core shift effect, with an unprecedented accuracy (a few micro-arcseconds). Millimeter VLBI observations with simultaneous multi-frequency receiver systems, like those of the KVN, enable us to explore the innermost regions of AGN and high precision astrometry. Such a system is capable of locating the frequency dependent opacity changes accurately. We have conducted the feasibility test-observations with the interested partners by implementing the KVN-compatible systems. Here we describe the science case for measuring the core shift effect in the AGN jet and report progress and future plans on extending the simultaneous multi-frequency system to global baselines.
Keywords
techniques: interferometeric; astrometry; high angular resolution; radio continuum: active galactic nuclei;
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