Development of a new wideband heterodyne receiver system for the Osaka 1.85 m mm-submm telescope: Receiver development and the first light of simultaneous observations in 230 GHz and 345 GHz bands with an SIS-mixer with 4-21 GHz IF output
Development of a new wideband heterodyne receiver system for the Osaka 1.85 m mm-submm telescope: Receiver development and the first light of simultaneous observations in 230 GHz and 345 GHz bands with an SIS-mixer with 4-21 GHz IF output
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为 Osaka 1.85 m mm-submm 望远镜开发新型宽带外差接收器系统：接收器开发以及使用具有 4-21 GHz IF 输出的 SIS 混频器在 230 GHz 和 345 GHz 频段同时观测的第一束光
DOI：
10.1093/pasj/psab046
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发表时间：
2021
影响因子：
2.3
通讯作者：
Sakai R.,
中科院分区：
文献类型：
--
作者：
Masui S.;Yamasaki Y.;Ogawa H.;Kondo H.;Yokoyama K.;Matsumoto T.;Minami T.;Okawa M.;Konishi R.;Kawashita S.;Konishi A.;Nakao Y.;Nishimoto S.;Yoneyama S.;Ueda S.;Hasegawa Y.;Fujita S.;Nishimura A.;Kojima T.;Uemizu K.;Kaneko K.;Sakai R.,
我们用大坂1.85米毫米-亚毫米望远镜研制了一个同时观测J = 2 - 1和J = 3 - 2跃迁CO谱线的宽带接收系统。作为频率分离系统，我们开发了连接三种双工器的多路复用器，每种双工器由分支线耦合器和高通滤波器组成。射频（RF）信号最终被分配到四个频带中，每个频带被馈送到超导体-绝缘体-超导体（SIS）混频器。来自喇叭的RF信号被具有分数带宽的宽带双工器分成两个频带，然后每个频带被每个双工器进一步分成两个频带。所开发的多路复用器的设计，制造和使用矢量网络分析仪的特点。测量结果与模拟结果吻合较好。通过连接SIS混频器测量接收机噪声温度，其中一个具有宽带4 - 21 GHz中频（IF）输出。接收机噪声温度在220 GHz频段测量为100K，在230 GHz频段测量为100K，在330 GHz频段测量为110 - 175 K，在345 GHz频段测量为150 - 250 K。该接收系统已安装在野边山射电观测站的1.85米望远镜上。我们成功地同时观测了J = 2 - 1和J = 3 - 2向猎户座KL跃迁的6条CO同位素谱线，以及向猎户座KL和W 51的动态映射。
We have developed a wideband receiver system for simultaneous observations in CO lines ofJ= 2–1 andJ= 3–2 transitions using the Osaka 1.85 m mm–submm telescope. As a frequency separation system, we developed multiplexers that connect three types of diplexers, each consisting of branch-line couplers and high-pass filters. The radio frequency (RF) signal is eventually distributed into four frequency bands, each of which is fed to a superconductor–insulator–superconductor (SIS) mixer. The RF signal from the horn is divided into two frequency bands by a wideband diplexer with a fractional bandwidth of, and then each frequency band is further divided into two bands by each diplexer. The developed multiplexers were designed, fabricated, and characterized using a vector network analyzer. The measurement results showed good agreement with the simulation. The receiver noise temperature was measured by connecting the SIS-mixers, one of which has a wideband 4–21 GHz intermediate frequency (IF) output. The receiver noise temperatures were measured to be ∼70 K in the 220 GHz band, ∼100 K in the 230 GHz band, 110–175 K in the 330 GHz band, and 150–250 K in the 345 GHz band. This receiver system has been installed on the 1.85 m telescope at the Nobeyama Radio Observatory. We succeeded in simultaneous observations of six CO isotopologue lines with the transitions ofJ= 2–1 andJ= 3–2 toward the Orion KL as well as on-the-fly mappings toward the Orion KL and W 51.