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Assistant Professor    Hada, Kazuhiro

Research Field

  • Radio astronomy, High energy astrophysics, Very-long-baseline-interferometer (VLBI), Active Galactic Nuclei, Relativistic jets

Brief Introduction of Research

  • Active Galactic Nuclei (AGN) are the most energetic phenomena in the Universe. They are ultimately powered by the central accreting supermassive black holes, and exhibit various high-energy activities such as powerful relativistic jets. I am working on observational studies of such energetic structures in AGN using the VLBI technique, which allows us to resolve and probe the immediate vicinity of the central black holes at an unprecedented high angular resolution. I am also working on the promotion of next-generation international VLBI facilities such as East-Asian VLBI Network and Event Horizon Telescope.

Main Research Achievements

  • EHT Collaboration et al. 2019, ApJL 875, L1~L6, “First M87 Event Horizon Telescope Results. I~VI”
  • Hada, K. et al. 2016, ApJ, 817, 131-147, “High-sensitivity 86GHz (3.5mm) VLBI observations of M87: deep imaging of the jet base at a resolution of 10 Schwarzschild radii”
  • Hada, K. et al. 2014, ApJ, 788, 165-177, “A strong radio brightening at the jet base of M87 during the elevated very-high-energy gamma-ray state in 2012”
  • Hada, K., et al. 2011, Nature, 477, 185-187, “An origin of the radio jet in M87 at the location of the central black hole”

Web Page


  • kazuhiro.hada[at]
    (In the mailing address, replace [at] with @)