The QCAL-1 KVN 43 GHz calibrator survey
In December 2011 a VLBI survey of bright compact extragalactic radio
sources was made at 43 GHz with the Korean VLBI Network. As a result of
this work the catalog of correlated flux densities in three ranges
of baseline projection lengths of 637 sources from a 43 GHz
(Q-band) was made. Of them, 623 sources have not been observed before
at Q-band with VLBI. The goal of this work in the early science phase
of the new VLBI array is twofold: to evaluate the performance of the
new instrument that operates in a frequency range of 22–129 GHz
and to build a list of objects that can be used as targets and
as calibrators. We have observed the list of 799 target sources with
declinations down to -40°. Among them, 724 were observed before with
VLBI at 22 GHz and had correlated flux densities greater than 200 mJy.
The overall detection rate is 78%. The detection limit, defined as the
minimum flux density for a source to be detected with 90% probability
in a single observation, was in a range of 115–180 mJy depending
on declination. However, some sources as week as 70 mJy have been detected.
Of 623 detected sources, 33 objects are detected for the first time in
VLBI mode. We determined their coordinates with the median formal
uncertainty 20 mas. The results of this work set the basis for future efforts
to build the complete flux-limited sample of extragalactic sources at frequencies
22 GHz and higher at 3/4 of the celestial sphere.
Results
Results of this work are submitted to Astronomical Journal,
preprint arxiv.org/1207.5872,
paper Leonid Petrov, Sang-Sung Lee, Jongsoo Kim, Taehyun Jung,
Junghwan Oh, Bong Won Sohn, Do-Young Byun, Moon-Hee Chung, Do-Heung Je,
Seog-Oh Wi, Min-Gyu Song, Jiman Kang, Seog-Tae Han, Jung-Won Lee, Bong Gyu Kim,
Hyunsoo Chung, Hyun-Goo Kim, "Early science with Korean VLBI network: the
QCAL-1 KVN 43~GHz calibrator survey", Astronomical Journal, 2012, submitted.
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Last update: 2012.07.26_23:37:41