Masumichi Seta

Major research fields

MasumichiSetaRadio Astronomy, Astronomical Instrumentation, Interstellar Medium

My research mainly focuses on developing instruments for radio telescopes that include highly sensitive heterodyne receiver, cooling system, intensity calibrating system, and optics. We design, assemble, and evaluate the instruments in our laboratory.

We are also interested in observations of interstellar medium using radio telescopes. Stars from in molecular clouds. We try to reveal how molecular clouds are born and evolve in our galaxy and nearby galaxies. We operate our own portable sub-millimeter telescope for observation of Milky Way in the CO (J=4-3) and [CI] lines. We are also interested in evolution of galaxies in early universe. Sub-millimeter observations provide important information on formation and evolution of molecular clouds and galaxies.

However sub-millimeter observation is difficult because earth atmosphere absorb strongly the radiation at sub-millimeter wavelengths. Dry and high altitude site are required for the sub-millimeter observations. Dome Fuji in Antarctic high plateau is the best site for sub-millimeter and terahertz astronomy on ground because of its high altitude of 3810m and low average temperature of -54℃. We demonstrated that opacity at 220 GHz from Dome Fuji in summer is good and stable. We belong to Japanese Consortium of Antarctic Astronomy. We plant to build a sub-millimeter observatory in Antarctica.

Major relevant publications

  1. M. Seta, N. Nakai, S. Ishii, M. Nagai, Y. Miyamoto, T., Ichikawa, N. Takato, H. Motoyama, “Dome Fuji in n Antarctica as a Site for Infrared and Terahertz Astronomy”, Astrophysics from Antarctica ", IAU Symposium 288, 251-255, 2013.
  2. S. Ishi, M. Seta, N. Nakai, N. Miyagawa, A. Yamauchi, H. Motoyama, M. Taguchi, “Site Testing at Dome Fuji for Submillimeter and Terahertz Astronomy”, Polar Science, 3, 213-221, 2010.
  3. M. Seta, T. Hasegawa, S. Sakamoto, T. Oka, T. Sawada, S. Inutsuka, H. Koyama, M. Hayashi “Detection of Shocked Molecular Gas by Full-Extent Mapping of the Supernova Remnant W44”, The Astronomical Journal, 127, 2, 1098-1116, 2004.
  4. Y. Miyamoto, N. Nakai, M. Seta, S. Dragan, H. Kenzaburo, M. Nagai,S. Ishii, A. Yamauchi, “Hot ammonia in the center of the Seyfert 2 galaxy NGC 3079”, Publications of the Astronomical Society of Japan, 67,1,515, 2015
  5. T. Sashida, T. Oka, K. Tanaka, K. Ando, M. Matsumura, M. Nagai, M. Seta “Kinematics of Shocked Molecular Gas adjacent to the Supernova Remnant W44” he Astrophysical Journal, 774,10(7p), 2013.