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AMPLITUDE CORRECTION FACTORS OF KOREAN VLBI NETWORK OBSERVATIONS
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 Title & Authors
AMPLITUDE CORRECTION FACTORS OF KOREAN VLBI NETWORK OBSERVATIONS
LEE, SANG-SUNG; BYUN, DO-YOUNG; OH, CHUNG SIK; KIM, HYO RYOUNG; KIM, JONGSOO; JUNG, TAEHYUN; OH, SE-JIN; ROH, DUK-GYOO; JUNG, DONG-KYU; YEOM, JAE-HWAN;
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 Abstract
We report results of investigation of amplitude calibration for very long baseline interferometry (VLBI) observations with Korean VLBI Network (KVN). Amplitude correction factors are estimated based on comparison of KVN observations at 22 GHz correlated by Daejeon hardware correlator and DiFX software correlator in Korea Astronomy and Space Science Institute (KASI) with Very Long Baseline Array (VLBA) observations at 22 GHz by DiFX software correlator in National Radio Astronomy Observatory (NRAO). We used the observations for compact radio sources, 3C 454.3, NRAO 512, OJ 287, BL Lac, 3C 279, 1633+382, and 1510–089, which are almost unresolved for baselines in a range of 350-477 km. Visibility data of the sources obtained with similar baselines at KVN and VLBA are selected, fringe-fitted, calibrated, and compared for their amplitudes. We find that visibility amplitudes of KVN observations should be corrected by factors of 1.10 and 1.35 when correlated by DiFX and Daejeon correlators, respectively. These correction factors are attributed to the combination of two steps of 2-bit quantization in KVN observing systems and characteristics of Daejeon correlator.
 Keywords
Techniques: interferometric;Instrumentation: interferometers;Radio continuum: galaxies;
 Language
English
 Cited by
1.
SPATIALLY RESOLVED HCN ABSORPTION FEATURES IN THE CIRCUMNUCLEAR REGION OF NGC 1052, The Astrophysical Journal, 2016, 830, 1, L3  crossref(new windwow)
2.
VLBI observations of flared optical quasar CGRaBS J0809+5341, Publications of the Astronomical Society of Japan, 2016, 68, 5, 77  crossref(new windwow)
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