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A NEW HARDWARE CORRELATOR IN KOREA: PERFORMANCE EVALUATION USING KVN OBSERVATIONS
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 Title & Authors
A NEW HARDWARE CORRELATOR IN KOREA: PERFORMANCE EVALUATION USING KVN OBSERVATIONS
Lee, Sang-Sung; Oh, Chung Sik; Roh, Duk-Gyoo; Oh, Se-Jin; Kim, Jongsoo; Yeom, Jae-Hwan; Kim, Hyo Ryoung; Jung, Dong-Gyu; Byun, Do-Young; Jung, Taehyun; Kawaguchi, Noriyuki; Shibata, Katsunori M.; Wajima, Kiyoaki;
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 Abstract
We report results of the performance evaluation of a new hardware correlator in Korea, the Daejeon correlator, developed by the Korea Astronomy and Space Science Institute (KASI) and the National Astronomical Observatory of Japan (NAOJ). We conduct Very Long Baseline Interferometry (VLBI) observations at 22 GHz with the Korean VLBI Network (KVN) in Korea and the VLBI Exploration of Radio Astrometry (VERA) in Japan, and correlated the aquired data with the Daejeon correlator. For evaluating the performance of the new hardware correlator, we compare the correlation outputs from the Daejeon correlator for KVN observations with those from a software correlator, the Distributed FX (DiFX). We investigate the correlated flux densities and brightness distributions of extragalactic compact radio sources. The comparison of the two correlator outputs shows that they are consistent with each other within < 8%, which is comparable with the amplitude calibration uncertainties of KVN observations at 22 GHz. We also find that the 8% difference in flux density is caused mainly by (a) the difference in the way of fringe phase tracking between the DiFX software correlator and the Daejeon hardware correlator, and (b) an unusual pattern (a double-layer pattern) of the amplitude correlation output from the Daejeon correlator. The visibility amplitude loss by the double-layer pattern is as small as 3%. We conclude that the new hardware correlator produces reasonable correlation outputs for continuum observations, which are consistent with the outputs from the DiFX software correlator.
 Keywords
Techniques: interferometric;Instrumentation: interferometers;Radio continuum: galaxies;Masers;
 Language
English
 Cited by
1.
AMPLITUDE CORRECTION FACTORS OF KOREAN VLBI NETWORK OBSERVATIONS,;;;;;;;;;;

천문학회지, 2015. vol.48. 5, pp.229-236 crossref(new window)
2.
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천문학회지, 2015. vol.48. 5, pp.285-298 crossref(new window)
3.
PAGAN II: THE EVOLUTION OF AGN JETS ON SUB-PARSEC SCALES,;;;;;;;;;;

천문학회지, 2015. vol.48. 5, pp.299-311 crossref(new window)
4.
대전상관기에서 복층패턴 문제의 해결에 관한 연구,오세진;노덕규;염재환;정동규;오충식;황주연;

한국신호처리시스템학회논문지, 2015. vol.16. 4, pp.162-167
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SPATIALLY RESOLVED HCN ABSORPTION FEATURES IN THE CIRCUMNUCLEAR REGION OF NGC 1052, The Astrophysical Journal, 2016, 830, 1, L3  crossref(new windwow)
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INTERFEROMETRIC MONITORING OF GAMMA-RAY BRIGHT AGNs. I. THE RESULTS OF SINGLE-EPOCH MULTIFREQUENCY OBSERVATIONS, The Astrophysical Journal Supplement Series, 2016, 227, 1, 8  crossref(new windwow)
3.
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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