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arXiv · 1903.11796

Source-Frequency Phase-Referencing Observation of AGNs with KaVA Using Simultaneous Dual-Frequency Receiving

Guang-Yao Zhao·Taehyun Jung·Bong Won Sohn·Motoki Kino·Mareki Honma·Richard Dodson·Maria Rioja·Seog-Tae Han·Katsunori Shibata·Do-Young Byun·Kazunori Akiyama·Juan-Carlos Algaba·Tao An·Xiaopeng Cheng·Ilje Cho·Yuzhu Cui·Kazuhiro Hada·Jeffrey A. Hodgson·Wu Jiang·Jee Won Lee·Jeong Ae Lee·Kotaro Niinuma·Jongho Park·Hyunwook Ro·Satoko Sawada-Satoh·Zhi-Qiang Shen·Fumie Tazaki·Sascha Trippe·Kiyoaki Wajima·Yingkang Zhang
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Abstract

The KVN(Korean VLBI Network)-style simultaneous multi-frequency receiving mode is demonstrated to be promising for mm-VLBI observations. Recently, other Very long baseline interferometry (VLBI) facilities all over the globe start to implement compatible optics systems. Simultaneous dual/multi-frequency VLBI observations at mm wavelengths with international baselines are thus possible. In this paper, we present the results from the first successful simultaneous 22/43 GHz dual-frequency observation with KaVA(KVN and VERA array), including images and astrometric results. Our analysis shows that the newly implemented simultaneous receiving system has brought a significant extension of the coherence time of the 43 GHz visibility phases along the international baselines. The astrometric results obtained with KaVA are consistent with those obtained with the independent analysis of the KVN data. Our results thus confirm the good performance of the simultaneous receiving systems for the non-KVN stations. Future simultaneous observations with more global stations bring even higher sensitivity and micro-arcsecond level astrometric measurements of the targets.

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Guang-Yao Zhao, Taehyun Jung, Bong Won Sohn, Motoki Kino, Mareki Honma, Richard Dodson, Maria Rioja, Seog-Tae Han, Katsunori Shibata, Do-Young Byun, Kazunori Akiyama, Juan-Carlos Algaba, Tao An, Xiaopeng Cheng, Ilje Cho, Yuzhu Cui, Kazuhiro Hada, Jeffrey A. Hodgson, Wu Jiang, Jee Won Lee, Jeong Ae Lee, Kotaro Niinuma, Jongho Park, Hyunwook Ro, Satoko Sawada-Satoh, Zhi-Qiang Shen, Fumie Tazaki, Sascha Trippe, Kiyoaki Wajima, Yingkang Zhang. 2019-03-28. Source-Frequency Phase-Referencing Observation of AGNs with KaVA Using Simultaneous Dual-Frequency Receiving. https://doi.org/10.5303/jkas.2019.52.1.23

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