世界で初めてのミリ波干渉計

The First mm-wave Interferometer for Astronomy in the world 1960-70s

  

Technology of mm-wave interferometry plays the essential role in the 
high-resolution observations using the modern facilities such as 
ALMA, EHT, etc. It is used also in mm-raders and phased arrays.
For astronomy, mm-wave interferometry has the advantage as follows:

1. The highest-resolution imaging and spectroscopy is possible thanks to 
the shortest wavelength in the radio domain using the heterodyne technique.

2. mm-wave is transparent to the radio-opaque circumstances near the 
central objects such as the black-hole, dust torus in galaxies, and the 
solar chromosphere.

3. Wealth of interstellar molecular lines.

The millimeter wave interferometry was proposed and designed in the 
1960s by Kin-aki Kawabata and Yoshiaki Sofue, who built the 
world's first millimeter wave interferometer for astronomy at
the Department of Physics, Nagoya University.

Based on mm-wave experiments at 70 and 35 GHz with single dish telescopes, 
the construction of 8-element 35 GHz interferometer with the maximum 
baseline of 16 m for solar observations was accomplished in 1970-1971,
resulting in several papers on radio bursts and the chromosphere physics
of the quiet Sun as below. The Nagoya mm-wave interferometer was 
further developed to have 16 elements (32 m), joined by H Ogawa, and 
was operated till 1980's.

1972 Kawabata and Sofue PASJ: 35GHz Interferometer 
1973 Kawabata, Sofue, et al.  Sol.Phys: 35GHz Interferometer
1974 Kawabata et al PASJ: 35GHz Interferometer
1974 Ogawa et al PASJ: 35GHz Interferometer