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arXiv · 1406.4356

VLBI observations of bright AGN jets with KVN and VERA Array (KaVA): Evaluation of Imaging Capability

Kotaro Niinuma·Sang-Sung Lee·Motoki Kino·Bong Won Sohn·Kazunori Akiyama·Guang-Yao Zhao·Satoko Sawada-Satoh·Sascha Trippe·Kazuhiro Hada·Taehyun Jung·Yoshiaki Hagiwara·Richard Dodson·Shoko Koyama·Mareki Honma·Hiroshi Nagai·Aeree Chung·Akihiro Doi·Kenta Fujisawa·Myoung-Hee Han·Joeng-Sook Kim·Jeewon Lee·Jeong Ae Lee·Atsushi Miyazaki·Tomoaki Oyama·Kazuo Sorai·Kiyoaki Wajima·Jaehan Bae·Do-Young Byun·Se-Hyung Cho·Yoon Kyung Choi·Hyunsoo Chung·Moon-Hee Chung·Seog-Tae Han·Tomoya Hirota·Jung-Wook Hwang·Do-Heung Je·Takaaki Jike·Dong-Kyu Jung·Jin-Seung Jung·Ji-Hyun Kang·Jiman Kang·Yong-Woo Kang·Yukitoshi Kan-ya·Masahiro Kanaguchi·Noriyuki Kawaguchi·Bong Gyu Kim·Hyo Ryoung Kim·Hyun-Goo Kim·Jaeheon Kim·Jongsoo Kim·Kee-Tae Kim·Mikyoung Kim·Hideyuki Kobayashi·Yusuke Kono·Tomoharu Kurayama·Changhoon Lee·Jung-Won Lee·Sang Hyun Lee·Young Chol Minh·Naoko Matsumoto·Akiharu Nakagawa·Chung Sik Oh·Se-Jin Oh·Sun-Youp Park·Duk-Gyoo Roh·Tetsuo Sasao·Katsunori M. Shibata·Min-Gyu Song·Yoshiaki Tamura·Seog-Oh Wi·Jae-Hwan Yeom·Young Joo Yun
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Abstract

The Korean very-long-baseline interferometry (VLBI) network (KVN) and VLBI Exploration of Radio Astrometry (VERA) Array (KaVA) is the first international VLBI array dedicated to high-frequency (23 and 43 GHz bands) observations in East Asia. Here, we report the first imaging observations of three bright active galactic nuclei (AGNs) known for their complex morphologies: 4C 39.25, 3C 273, and M 87. This is one of the initial result of KaVA early science. Our KaVA images reveal extended outflows with complex substructure such as knots and limb brightening, in agreement with previous Very Long Baseline Array (VLBA) observations. Angular resolutions are better than 1.4 and 0.8 milliarcsecond at 23 GHz and 43 GHz, respectively. KaVA achieves a high dynamic range of ~1000, more than three times the value achieved by VERA. We conclude that KaVA is a powerful array with a great potential for the study of AGN outflows, at least comparable to the best existing radio interferometric arrays.

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Kotaro Niinuma, Sang-Sung Lee, Motoki Kino, Bong Won Sohn, Kazunori Akiyama, Guang-Yao Zhao, Satoko Sawada-Satoh, Sascha Trippe, Kazuhiro Hada, Taehyun Jung, Yoshiaki Hagiwara, Richard Dodson, Shoko Koyama, Mareki Honma, Hiroshi Nagai, Aeree Chung, Akihiro Doi, Kenta Fujisawa, Myoung-Hee Han, Joeng-Sook Kim, Jeewon Lee, Jeong Ae Lee, Atsushi Miyazaki, Tomoaki Oyama, Kazuo Sorai, Kiyoaki Wajima, Jaehan Bae, Do-Young Byun, Se-Hyung Cho, Yoon Kyung Choi, Hyunsoo Chung, Moon-Hee Chung, Seog-Tae Han, Tomoya Hirota, Jung-Wook Hwang, Do-Heung Je, Takaaki Jike, Dong-Kyu Jung, Jin-Seung Jung, Ji-Hyun Kang, Jiman Kang, Yong-Woo Kang, Yukitoshi Kan-ya, Masahiro Kanaguchi, Noriyuki Kawaguchi, Bong Gyu Kim, Hyo Ryoung Kim, Hyun-Goo Kim, Jaeheon Kim, Jongsoo Kim, Kee-Tae Kim, Mikyoung Kim, Hideyuki Kobayashi, Yusuke Kono, Tomoharu Kurayama, Changhoon Lee, Jung-Won Lee, Sang Hyun Lee, Young Chol Minh, Naoko Matsumoto, Akiharu Nakagawa, Chung Sik Oh, Se-Jin Oh, Sun-Youp Park, Duk-Gyoo Roh, Tetsuo Sasao, Katsunori M. Shibata, Min-Gyu Song, Yoshiaki Tamura, Seog-Oh Wi, Jae-Hwan Yeom, Young Joo Yun. 2014-06-17. VLBI observations of bright AGN jets with KVN and VERA Array (KaVA): Evaluation of Imaging Capability. https://doi.org/10.1093/pasj%2Fpsu104

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