A new millimeter VLBI network in Korea

We introduce a new millimeter very long baseline interferometry (VLBI) network in Korea, the Korean VLBI Network (KVN). The KVN is the first millimeter-dedicated VLBI network in East Asia. The KVN consists of three 21 m radio telescopes with baseline lengths in a range of 305–476 km. The quasi-optical system equipped on the antennas allows simultaneous observations at 22, 43, 86, and 129 GHz. The first fringes of the KVN were obtained at 22 GHz on 2010 June 8. Test observations at 22 and 43 GHz on 2010 September 30 and 2011 April 4 confirmed that the full cycle of VLBI observations works according to specification: scheduling, antenna control system, data recording, correlation, post-correlation data processing, astrometry, geodesy, and imaging analysis. The KVN is ready to image compact radio sources both in snapshot and full-track modes with residual noise in calibrated phases of less than 2 deg at 22 and 43 GHz and with dynamic ranges of 300 for snapshot mode and 1000 for full-track mode. The KVN will be open to the world, calling for proposals in 2014. We will introduce high-lights of science cases of KVN such as detection of 44 GHz methanol masers, observations of Zeeman splitting effect, VLBI fringe detection of 129GHz SiO masers from evolved stars.