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arXiv · 0706.1353

New 60-cm Radio Survey Telescope with the Sideband-Separating SIS Receiver for the 200 GHz Band

Taku Nakajima·Masahiro Kaiden·Jun Korogi·Kimihiro Kimura·Yoshinori Yonekura·Hideo Ogawa·Shingo Nishiura·Kazuhito Dobashi·Toshihiro Handa·Kotaro Kohno·Jun-Ichi Morino·Shin'ichiro Asayama·Takashi Noguchi
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Abstract

We have upgraded the 60-cm radio survey telescope located in Nobeyama, Japan. We developed a new waveguide-type sideband-separating SIS mixer for the telescope, which enables the simultaneous detection of distinct molecular emission lines both in the upper and lower sidebands. Over the RF frequency range of 205-240 GHz, the single-sideband receiver noise temperatures of the new mixer are 40-100 K for the 4.0-8.0 GHz IF frequency band. The image rejection ratios are greater than 10 dB over the same range. For the dual IF signals obtained by the receiver, we have developed two sets of acousto-optical spectrometers and a telescope control system. Using the new telescope system, we successfully detected the 12CO (J=2-1) and 13CO (J=2-1) emission lines simultaneously toward Orion KL in 2005 March. Using the waveguide-type sideband-separating SIS mixer for the 200 GHz band, we have initiated the first simultaneous 12CO (J=2-1) and 13CO (J=2-1) survey of the galactic plane as well as large-scale mapping observations of nearby molecular clouds.

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Taku Nakajima, Masahiro Kaiden, Jun Korogi, Kimihiro Kimura, Yoshinori Yonekura, Hideo Ogawa, Shingo Nishiura, Kazuhito Dobashi, Toshihiro Handa, Kotaro Kohno, Jun-Ichi Morino, Shin'ichiro Asayama, Takashi Noguchi. 2007-06-10. New 60-cm Radio Survey Telescope with the Sideband-Separating SIS Receiver for the 200 GHz Band. https://doi.org/10.1093/pasj%2F59.5.1005

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