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Title: EARLY SCIENCE WITH THE KOREAN VLBI NETWORK: THE QCAL-1 43 GHz CALIBRATOR SURVEY

Abstract

This paper presents the catalog of correlated flux densities in three ranges of baseline projection lengths of 637 sources from a 43 GHz (Q band) survey observed with the Korean VLBI Network. Of them, 14 objects used as calibrators were previously observed, but 623 sources have not been observed before in the Q band with very long baseline interferometry (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 Degree-Sign . 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 the range of 115-180 mJy depending on declination. However, some sources as weak as 70 mJy have been detected. Of 623 detected sources, 33more » objects are detected for the first time in VLBI mode. We determined their coordinates with a median formal uncertainty of 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 of 22 GHz and higher at 3/4 of the celestial sphere.« less

Authors:
 [1]; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;  [2]
  1. Astrogeo Center, Falls Church, VA 22043 (United States)
  2. Korean VLBI Network, Korea Astronomy and Space Science Institute, 776, Daedeokdae-ro, Yuseong-gu, Daejeon 305-348 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22089811
Resource Type:
Journal Article
Journal Name:
Astronomical Journal (New York, N.Y. Online)
Additional Journal Information:
Journal Volume: 144; Journal Issue: 5; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1538-3881
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; CATALOGS; COORDINATES; COSMIC RADIO SOURCES; FLUX DENSITY; GALAXIES; GHZ RANGE; INTERFEROMETRY; PROBABILITY; RADIOASTRONOMY; SENSITIVITY

Citation Formats

Petrov, Leonid, Lee, Sang-Sung, Kim, Jongsoo, Jung, Taehyun, Oh, Junghwan, Sohn, Bong Won, Byun, Do-Young, Chung, Moon-Hee, Je, Do-Heung, Wi, Seog-Oh, Song, Min-Gyu, Kang, Jiman, Han, Seog-Tae, Lee, Jung-Won, Kim, Bong Gyu, Chung, Hyunsoo, and Kim, Hyun-Goo, E-mail: sslee@kasi.re.kr. EARLY SCIENCE WITH THE KOREAN VLBI NETWORK: THE QCAL-1 43 GHz CALIBRATOR SURVEY. United States: N. p., 2012. Web. doi:10.1088/0004-6256/144/5/150.
Petrov, Leonid, Lee, Sang-Sung, Kim, Jongsoo, Jung, Taehyun, Oh, Junghwan, Sohn, Bong Won, Byun, Do-Young, Chung, Moon-Hee, Je, Do-Heung, Wi, Seog-Oh, Song, Min-Gyu, Kang, Jiman, Han, Seog-Tae, Lee, Jung-Won, Kim, Bong Gyu, Chung, Hyunsoo, & Kim, Hyun-Goo, E-mail: sslee@kasi.re.kr. EARLY SCIENCE WITH THE KOREAN VLBI NETWORK: THE QCAL-1 43 GHz CALIBRATOR SURVEY. United States. doi:10.1088/0004-6256/144/5/150.
Petrov, Leonid, Lee, Sang-Sung, Kim, Jongsoo, Jung, Taehyun, Oh, Junghwan, Sohn, Bong Won, Byun, Do-Young, Chung, Moon-Hee, Je, Do-Heung, Wi, Seog-Oh, Song, Min-Gyu, Kang, Jiman, Han, Seog-Tae, Lee, Jung-Won, Kim, Bong Gyu, Chung, Hyunsoo, and Kim, Hyun-Goo, E-mail: sslee@kasi.re.kr. Thu . "EARLY SCIENCE WITH THE KOREAN VLBI NETWORK: THE QCAL-1 43 GHz CALIBRATOR SURVEY". United States. doi:10.1088/0004-6256/144/5/150.
@article{osti_22089811,
title = {EARLY SCIENCE WITH THE KOREAN VLBI NETWORK: THE QCAL-1 43 GHz CALIBRATOR SURVEY},
author = {Petrov, Leonid and Lee, Sang-Sung and Kim, Jongsoo and Jung, Taehyun and Oh, Junghwan and Sohn, Bong Won and Byun, Do-Young and Chung, Moon-Hee and Je, Do-Heung and Wi, Seog-Oh and Song, Min-Gyu and Kang, Jiman and Han, Seog-Tae and Lee, Jung-Won and Kim, Bong Gyu and Chung, Hyunsoo and Kim, Hyun-Goo, E-mail: sslee@kasi.re.kr},
abstractNote = {This paper presents the catalog of correlated flux densities in three ranges of baseline projection lengths of 637 sources from a 43 GHz (Q band) survey observed with the Korean VLBI Network. Of them, 14 objects used as calibrators were previously observed, but 623 sources have not been observed before in the Q band with very long baseline interferometry (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 Degree-Sign . 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 the range of 115-180 mJy depending on declination. However, some sources as weak 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 a median formal uncertainty of 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 of 22 GHz and higher at 3/4 of the celestial sphere.},
doi = {10.1088/0004-6256/144/5/150},
journal = {Astronomical Journal (New York, N.Y. Online)},
issn = {1538-3881},
number = 5,
volume = 144,
place = {United States},
year = {2012},
month = {11}
}