Perspective | Published:

Capabilities and prospects of the East Asia Very Long Baseline Interferometry Network

Nature Astronomyvolume 2pages118125 (2018) | Download Citation

Abstract

The very long baseline interferometry (VLBI) technique offers angular resolutions superior to any other instruments at other wavelengths, enabling unique science applications of high-resolution imaging of radio sources and high-precision astrometry. The East Asia VLBI Network (EAVN) is a collaborative effort in the East Asian region. The EAVN currently consists of 21 telescopes with diverse equipment configurations and frequency setups, allowing flexible subarrays for specific science projects. The EAVN provides the highest resolution of 0.5 mas at 22 GHz, allowing the fine imaging of jets in active galactic nuclei, high-accuracy astrometry of masers and pulsars, and precise spacecraft positioning. The soon-to-be-operational Five-hundred-meter Aperture Spherical radio Telescope (FAST) will open a new era for the EAVN. This state-of-the-art VLBI array also provides easy access to and crucial training for the burgeoning Asian astronomical community. This Perspective summarizes the status, capabilities and prospects of the EAVN.

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Acknowledgements

T.A. thanks the grant supported by the Ministry of Science and Technology of China (2016YFE0100300), the Youth Innovation Promotion Association and FAST Fellowship of Chinese Academy of Sciences. H.I. thanks the grants supported by KAKENHI (16H02167) and the Korea Astronomy and Space Science Institute Commissioning Program. The authors are grateful to the engineering and scientific teams of the EAVN for test experiments. The authors thank Y. Hagiwara for his contribution in preparing the draft, W. Baan, D. Byun, R. Dodson, S. Frey, K. Fujisawa, K. Hada, M. Honma, D.R. Jiang, T. Jung, M. Kino, S.-S. Lee, D. Li, P. Mohan, R.D. Nan, C.S. Oh, Z.H. Qian, M. Rioja, K. Shibata, F.W. Tong, K. Wajima, N. Wang, S.H. Ye, Y. Yonekura and Y.J. Yun for comments on the manuscript and for providing helpful information. B.W.S. is grateful for the support of the National Research Council of Science and Technology, Korea (EU-16-001).

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Affiliations

  1. Shanghai Astronomical Observatory, Key Laboratory of Radio Astronomy, Chinese Academy of Sciences, Nandan Road 80, Shanghai, 200030, China

    • T. An
  2. Key Laboratory of Cognitive Radio and Information Processing, Guilin University of Electronic Technology, 541004, Guilin, China

    • T. An
  3. Korea Astronomy and Space Science Institute, 776 Daedeokdae-ro, Yuseong-gu, Daejeon, 34055, Republic of Korea

    • B. W. Sohn
  4. Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima, 890-0065, Japan

    • H. Imai

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Contributions

T.A. coordinated the writing of the paper. All authors have contributed to the EAVN commissioning and the preparation for this Perspective.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to T. An.

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https://doi.org/10.1038/s41550-017-0277-z