On-Sky Performance of the SPT-3G Frequency-Domain Multiplexed Readout

Journal Article · 16 December 2019 · Journal of Low Temperature Physics

DOI: https://doi.org/10.1007/s10909-019-02280-w · OSTI ID:1616755

Bender, A. N. ; Anderson, A. J.; Avva, J. S.; Ade, P. A. R.; Ahmed, Z.; Barry, P. S.; Basu Thakur, R.; Benson, B. A.; Bryant, L.; Byrum, K.; Carlstrom, J. E.; Carter, F. W.; Cecil, T. W.; Chang, C. L.; Cho, H. -M.; Cliche, J. F.; Cukierman, A.; de Haan, T.; Denison, E. V.; Ding, J. ; Dobbs, M. A.; Dutcher, D.; Everett, W.; Ferguson, K. R.; Foster, A.; Fu, J.; Gallicchio, J.; Gambrel, A. E.; Gardner, R. W.; Gilbert, A.; Groh, J. C.; Guns, S.; Guyser, R.; Halverson, N. W.; Harke-Hosemann, A. H.; Harrington, N. L.; Henning, J. W.; Hilton, G. C.; Holzapfel, W. L.; Howe, D.; Huang, N.; Irwin, K. D.; Jeong, O. B.; Jonas, M.; Jones, A.; Khaire, T. S.; Kofman, A. M.; Korman, M.; Kubik, D. L.; Kuhlmann, S.; Kuo, C. -L.; Lee, A. T.; Leitch, E. M.; Lowitz, A. E.; Meyer, S. S.; Michalik, D.; Montgomery, J.; Nadolski, A.; Natoli, T.; Nguyen, H.; Noble, G. I.; Novosad, V.; Padin, S.; Pan, Z.; Paschos, P.; Pearson, J.; Posada, C. M.; Quan, W.; Rahlin, A.; Riebel, D.; Ruhl, J. E.; Sayre, J. T.; Shirokoff, E.; Smecher, G.; Sobrin, J. A.; Stark, A. A.; Stephen, J.; Story, K. T.; Suzuki, A.; Thompson, K. L.; Tucker, C.; Vale, L. R.; Vanderlinde, K.; Vieira, J. D.; Wang, G.; Whitehorn, N.; Yefremenko, V.; Yoon, K. W.; Young, M. R.

Frequency-domain multiplexing (fMux) is an established technique for the readout of large arrays of transition-edge sensor (TES) bolometers. Each TES in a multiplexing module has a unique AC voltage bias that is selected by a resonant filter. This scheme provides for the operation and readout of multiple bolometers on a single pair of wires, reducing thermal loading onto sub-Kelvin stages. The current receiver on the South Pole Telescope, SPT-3G, uses a 68x fMux system to operate its large-format camera of ~16,000 TES bolometers. We present here the successful implementation and performance of the SPT-3G readout as measured on-sky. Characterization of the noise reveals a median pair-differenced 1/f knee frequency of 33 mHz, indicating that low-frequency noise in the readout will not limit SPT-3G’s measurements of sky power on large angular scales. Measurements further show that the median readout white noise level in each of the SPT-3G observing bands is below the expectation for photon noise, demonstrating that SPT-3G is operating in the photon-noise-dominated regime.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: Alfred P. Sloan Foundation; Australian Research Council; Canadian Institute for Advanced Research; Canadian Institute for Advanced Research (CIFAR); Gordon and Betty Moore Foundation; Kavli Foundation; National Science Foundation (NSF); Natural Sciences and Engineering Research Council of Canada; Natural Sciences and Engineering Research Council of Canada (NSERC); Sloan Foundation; USDOE; USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: SPT Collaboration
• Grant/Contract Number: AC02-06CH11357; AC02-07CH11359; AC02-76SF00515
• OSTI ID: 1616755
• Journal Information: Journal of Low Temperature Physics, Journal Name: Journal of Low Temperature Physics Journal Issue: 1-2 Vol. 199; ISSN 0022-2291
• Publisher: SpringerCopyright Statement
• Country of Publication: United States
• Language: English