Abstract-Terahertz Superconducting Radiometric Spectrometer in Tibet for Atmospheric Science

Sheng Li, Qijun Yao, Dong Liu, Wenying Duan, Kun Zhang, Junda Jin, Zhenhui Lin, Feng Wu, Jinping Yang, Wei Miao, Shengcai Shi

https://link.springer.com/article/10.1007/s10762-018-0557-4

Terahertz superconducting radiometric spectrometer (TSRS), as one of seven instruments of the atmospheric profiling synthetic observation system (APSOS) project, was completed in the middle of 2017 after 5 years of development. It is a dual-band heterodyne receiver system based on high sensitive superconductor-insulator-superconductor (SIS) mixers which cover the frequency range of 180 to 380 GHz. With fast Fourier transform spectrometer (FFTS) of each band, real-time observation of 2 GHz bandwidth of high spectral resolution atmospheric molecular emission lines has been demonstrated. TSRS has been deployed at Yangbajing site, which stands on the Qinghai-Tibet Plateau at an altitude of 4300 m in southwestern China, since October 2017. It has been worked in a preliminary observation phase along with other active observation equipment of APSOS. Since then, ozone emission lines around 236 GHz and 358 GHz have been monitored simultaneously. Achieved data will be used to retrieve the in situ vertical distribution of ozone and its movement among different layers of the atmosphere

Abstract-THz Vector Field Measurement Comparison Between On-the-Fly and Step Scan Method

Jie Hu, Zheng Lou, Qi-Jun Yao,  Wei Miao, Jin-Ping Yang,  Zhen-Hui Lin,  Sheng-Cai Shi,

http://ieeexplore.ieee.org/document/7797489/

A fast terahertz vector field measurement system based on the on-the-fly (OTF) scan method is investigated. Compared with the step scan method, which samples at certain step, the OTF scan obtains the data with the scanner moving continuously, thus improving the measurement efficiency to some extent. The phase stability of the system is fully studied. Demonstration at approximately 500 GHz is compared with the result by the step scan method, showing that the OTF method can improve the measurement speed by a factor of 7 while the data accuracy is almost the same. Measurements at different scanning speeds and with different probes are also compared to understand their effects.

A THz Superconducting Imaging Array Developed for the DATE5 Telescope

Sheng-Cai Shi, Wen Zhang, Jing Li, Wei Miao, Zhen-Hui Lin, Zheng Lou, Qi-Jun Yao

http://paperity.org/p/74626764/a-thz-superconducting-imaging-array-developed-for-the-date5-telescope

Dome A in Antarctica, located at an altitude of 4093 m and with very low temperature in winter down to −83∘C, is an exceptionally dry site. Measurements of the atmospheric transmission in the range of 0.75–15 THz by a Far-infrared/THz Fourier transform spectrometer (FTS) strongly suggest that Dome A is a unique site for ground-based THz observations, especially for the 200- and 350-micron windows. A 5-m THz telescope (DATE5) is therefore proposed for Chinese Antarctic Kunlun Observatory. We are currently developing a THz superconducting imaging array (TeSIA) for the DATE5. The TeSIA will be working at the 350-\upmum window, with a pixel number of 32×32 and a sensitivity (NEP) of ∼10−16 W/Hz0.5. Ti transition-edge sensors with time-domain multiplexing and TiN microwave kinetic inductance detectors with frequency-domain multiplexing are both developed for the TeSIA. In this paper, detailed system designs and some measurement results will be presented.