Tianlai experiment
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The Tianlai experiment (Chinese: 天籁) is a radio astronomy experiment run by the National Astronomical Observatories, Chinese Academy of Sciences (NAOC).[1][2] Its aim is to develop the key techniques of intensity mapping observation for the redshifted 21cm line of neutral hydrogen, in order to probe the large-scale structure, and to detect and measure the dark energy using baryon acoustic oscillations (BAO). The experiment is currently at a pathfinder stage, two pathfinder interferometric imaging radio telescope arrays have been built for this experiment. These are the cylinder array and the dish array. In the full scale stage, the experiment is expected to measure the large scale structure, and use the BAO feature to detect the dark energy [3]
History
[edit]The "Key Technologies of Radio Detection of Dark Energy" research is funded in 2012. The NAOC team decided to choose this site in 2014, after surveying many sites in China.[4] The first full observation took place in 2016.[5] Between 2020 and 2022, new digital backends are installed on both the dish array and cylinder array, enable them to search for fast radio burst.[6][7]
Location
[edit]The Tianlai arrays are located at (91°48′ E, 44°09′ N), the signal collected by these arrays are transmitted via optical fiber to the station house, which is about 6 km away in the Hongliuxia village of the Balikun County, Xinjiang, China.[citation needed]
Status and Plan
[edit]Cylinder Array: This includes three adjacent, north-south oriented parabolic cylinder reflectors, with dimension of 15 meter wide and 40 meter long. However, only the central section of about 12.4 meters of each cylinder are used at present. A total of 96 dual polarization feed units are installed, with 31, 32 and 33 respectively on the three cylinders, all with the same total length, but with spacing of 41.33cm, 40cm, 38.75cm respectively.[8] This unequal spacing is designed to reduce grating lobes of the array [9]
Dish Array: This includes 16 dishes of 6 meter aperture arranged in concentric circles.[10][11]
The arrays are planned to carry out HI surveys and cross correlate with optical observations.[12]
International Collaboration
[edit]The Tianlai international collaboration have members from the US, France, and India. It has a weekly online meeting, and an annual collaboration meeting[13]
Name
[edit]The word "Tianlai" literally means "heavenly sound" in Chinese. It is a concept which was first used by the ancient Chinese philosopher Zhuang Zhou, to mean a hidden rhythm of the nature. It is also often used to describe beautiful music. Here it refers to the acoustic oscillation of the Early Universe[14]
References
[edit]- ^ Chen, Xuelei. "Radio detection of dark energy—the Tianlai project." Scientia Sinica Physica, Mechanica & Astronomica 41.12 (2011): 1358.
- ^ CHEN, Xuelei, "THE TIANLAI PROJECT: A 21CM COSMOLOGY EXPERIMENT", International Journal of Modern Physics: Conference SeriesVol. 12, pp. 256-263 (2012) https://www.worldscientific.com/doi/abs/10.1142/S2010194512006459
- ^ Xu, Yidong; Wang, Xin; Chen, Xuelei, Forecasts on the Dark Energy and Primordial Non-Gaussianity Observations with the Tianlai Cylinder Array, The Astrophysical Journal, Volume 798, Issue 1, article id. 40, 10 pp. (2015). https://arxiv.org/pdf/1410.7794.pdf
- ^ Wu, Fengquan, et al. "Site selection for the Tianlai experiment proceedings of the XXXIst URSI general assembly and scientific symposium to be held in Beijing, China (CIE), August 17–23, 2014." 2014 XXXIth URSI General Assembly and Scientific Symposium (URSI GASS). IEEE, 2014.
- ^ Das, Santanu, et al. "Progress in the construction and testing of the Tianlai radio interferometers." Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX. Vol. 10708. SPIE, 2018. https://arxiv.org/pdf/1806.04698.pdf
- ^ Yu, Zijie ; Deng, Furen ; Niu, Chenhui ; Li, Jixia ; Sun, Shijie ; Wang, Weiyang ; Wang, Yougang ; Wu, Fengquan ; Chen, Xuelei, Detection of a bright FRB with the Tianlai Cylinder Pathfinder Array https://www.astronomerstelegram.org/?read=15342
- ^ Yu, Zijie; Deng, Furen; Niu, Chenhui; Li, Jixia; Sun, Shijie; Wang, Weiyang; Wang, Yougang; Wu, Fengquan; Chen, Xuelei, Detection of FRB 20220912A at 750 MHz with the Tianlai Dish Pathfinder Array https://www.astronomerstelegram.org/?read=15342
- ^ Li, J., Zuo, S., Wu, F. et al. The Tianlai Cylinder Pathfinder array: System functions and basic performance analysis. Sci. China Phys. Mech. Astron. 63, 129862 (2020). https://doi.org/10.1007/s11433-020-1594-8
- ^ Zhang, Jiao, et al. "Sky reconstruction for the Tianlai cylinder array." Research in Astronomy and Astrophysics 16.10 (2016): 158. https://iopscience.iop.org/article/10.1088/1674-4527/16/10/158/pdf
- ^ Fengquan Wu, Jixia Li, Shifan Zuo, Xuelei Chen, Santanu Das, John P Marriner, Trevor M Oxholm, Anh Phan, Albert Stebbins, Peter T Timbie, Reza Ansari, Jean-Eric Campagne, Zhiping Chen, Yanping Cong, Qizhi Huang, Juhun Kwak, Yichao Li, Tao Liu, Yingfeng Liu, Chenhui Niu, Calvin Osinga, Olivier Perdereau, Jeffrey B Peterson, John Podczerwinski, Huli Shi, Gage Siebert, Shijie Sun, Haijun Tian, Gregory S Tucker, Qunxiong Wang, Rongli Wang, Yougang Wang, Yanlin Wu, Yidong Xu, Kaifeng Yu, Zijie Yu, Jiao Zhang, Juyong Zhang, Jialu Zhu, The Tianlai dish pathfinder array: design, operation, and performance of a prototype transit radio interferometer, Monthly Notices of the Royal Astronomical Society, Volume 506, Issue 3, September 2021, Pages 3455–3482, https://doi.org/10.1093/mnras/stab1802
- ^ Zhang, Jiao, et al. "Sky reconstruction from transit visibilities: PAON-4 and Tianlai dish array." Monthly Notices of the Royal Astronomical Society 461.2 (2016): 1950-1966.https://doi.org/10.1093/mnras/stw1458
- ^ Perdereau, Olivier ; Ansari, Réza ; Stebbins, Albert ; Timbie, Peter T. ; Chen, Xuelei search by orcid ; Wu, Fengquan ; Li, Jixia ; Marriner, John P. ; Tucker, Gregory S. ; Cong, Yanping ; Das, Santanu search by orcid ; Li, Yichao ; Liu, Yingfeng search by orcid ; Magneville, Christophe ; Peterson, Jeffrey B. ; Phan, Anh ; Robinthal, Lily ; Sun, Shijie ; Wang, Yougang search by orcid ; Wu, Yanlin ; Xu, Yidong search by orcid ; Yu, Kaifeng ; Yu, Zijie ; Zhang, Jiao ; Zhang, Juyong ; Zuo, Shifan, The Tianlai dish array low-z surveys forecasts, Monthly Notices of the Royal Astronomical Society, Volume 517, Issue 3, pp.4637-4655, https://doi.org/10.1093/mnras/stac2832
- ^ "Tianlai Project | Gallery".
- ^ Chen, Xuelei. "The Tianlai Project: A 21-cm Intensity Mapping Experiment." AAPPS Bulletin 25.5 (2015). https://web.s.ebscohost.com/abstract?direct=true&profile=ehost&scope=site&authtype=crawler&jrnl=02182203&AN=110040725&h=Ut%2b%2fIIvd8QHAEUc9jYyS1zJXCJd4HGresJP5ps8xj817fYMgPPzewLzd6wwi7eydK%2fXNTMzD4os4XwSdki8oGQ%3d%3d&crl=c&resultNs=AdminWebAuth&resultLocal=ErrCrlNotAuth&crlhashurl=login.aspx%3fdirect%3dtrue%26profile%3dehost%26scope%3dsite%26authtype%3dcrawler%26jrnl%3d02182203%26AN%3d110040725