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MEASURING THE CORE SHIFT EFFECT IN AGN JETS WITH THE EXTENDED KOREAN VLBI NETWORK
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 Title & Authors
MEASURING THE CORE SHIFT EFFECT IN AGN JETS WITH THE EXTENDED KOREAN VLBI NETWORK
JUNG, TAEHYUN; DODSON, RICHARD; HAN, SEOG-TAE; RIOJA, MARIA J.; BYUN, DO-YOUNG; HONMA, MAREKI; STEVENS, JAMIE; VICENTE, PABLO DE; SOHN, BONG WON;
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 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;
 Language
English
 Cited by
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