Colloq Abstract - Petrov

March 29, 2019

11:00am Mountain

Leonid Petrov (NASA)

 

Science with VLBI absolute astrometry

 

Abstract

 

The overview of the VLBI absolute astrometry program that ran for several decades will be given. The recent data release of Gaia   mission almost obliterated ground astrometry that has over two thousand years of history. Surprisingly, Gaia did not kill radio astrometry, and on the contrary, gave it a new strong science case. I will discuss the technology of large VLBI surveys, outline the current state of VLBI astrometry catalogues, and present scientific results that include population analysis, evaluation of the anisotropy of AGN sky distribution, variability core-shift, and explanation of VLBI/Gaia offsets. The use of the new observable, VLBI/Gaia position offset, for AGN physics will be discussed in detail.

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