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GroundBIRD: Observation of CMB Polarization with a Rapid Scanning and MKIDs


Cosmic microwave background (CMB) radiation is an afterglow from the Big Bang. CMB contains rich information about the early stage of the universe. In particular, odd-parity patterns (B-mode) in the CMB polarization on a large angular scale would provide an evidence of the cosmic inflation. The aim of the GroundBIRD experiment is to observe the B-mode on large angular scales from the ground. One of the most novel characteristics of the telescope used for this experiment is its rapid rotational scanning technique. In addition, the telescope uses cold optics and microwave kinetic inductance detectors. We have developed a telescope mount with a three-axis rotation mechanism (azimuth, elevation, and boresight) and measured the vibration at the focal plane stage at 20 RPM scan rotation rate. We also performed focal plane detector tests on this mount. The tests confirmed the expected response from the geomagnetism associated with the mount rotation. We have also developed a design for the magnetic shields and a detector array on a 3-in wafer. The preparations to begin the observations at the Teide Observatory in the Canary Islands in 2018 are proceeding smoothly.

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  1. A.R. Liddle, D.H. Lyth, Cosmological Inflation and Large-Scale Structure (Cambridge University Press, Cambridge, 2000)

    Book  Google Scholar 

  2. U. Seljak, M. Zaldarriaga, Signature of gravity waves in the polarization of the microwave background. Phys. Rev. Lett. 78, 2054–2057 (1997)

    ADS  Article  Google Scholar 

  3. S. Oguri, J. Choi, T. Damayanthi, M. Hattori, M. Hazumi, H. Ishitsuka, K. Karatsu, S. Mima, M. Minowa, T. Nagasaki, C. Otani, Y. Sekimoto, O. Tajima, N. Tomita, M. Yoshida, E. Won, Groundbird: observing cosmic microwave polarization at large angular scale with kinetic inductance detectors and high-speed rotating telescope. J. Low Temp. Phys. 184(3), 786–792 (2016)

    ADS  Article  Google Scholar 

  4. C.L. Bennett et al., Astrophys. J. Suppl. Ser. (2013).

    ADS  Article  Google Scholar 

  5. J.R. Eimer et al., AA, 520, A1 (2010)

  6. D.T. Chuss et al., Proc. SPIE (2010).

  7. J.R. Eimer et al., in Proc. SPIE 8452 845220 (2012)

  8. The QUIET Collaboration. Astrophys. J. 741 (2011)

  9. S. Oguri et al. Groundbird: observations of cmb polarization with fast scan modulation and mkids, in Proc. SPIE (2016)

  10. J. Choi, H. Ishitsuka, S. Mima, S. Oguri, K. Takahashi, O. Tajima, Radio-transparent multi-layer insulation for radiowave receivers. Rev. Sci. Instrum. 84(11), 114502 (2013)

    ADS  Article  Google Scholar 

  11. J. E. Austermannc J. A. Bealld D. Beckerd B. A. Bensone L. E. Bleeme J. Brittond C. L. Change J. E. Carlstrome H. M. Chod A. T. Critese T. EssingerHilemanb W. Everette N. W. Halversonc J. W. Henningc G. C. Hiltond K. D. Irwind J. Mehle S. S. Meyere S. Mossleyf M. D. Niemackd L. P. Parkerb S. M. Simonc S. T. Staggsb C. Visnjicb E. Wollackf K. U. Yenf K. W. Yoond J. McMahona, J. W. Appelb and Y. Zhaob. Planar orthomode transducers for feedhorn-coupled tes polarimaters, in AIP Conference Proceedings, 1185 (2009)

  12. H. Kutsuma et al., J. Low Temp. Phys., this Special Issue LTD17 (2018).

    ADS  Article  Google Scholar 

  13. H. Ishitsuka, M. Ikeno, S. Oguri, O. Tajima, N. Tomita, T. Uchida, Front-end electronics for the array readout of a microwave kinetic inductance detector towards observation of cosmic microwave background polarization. J. Low Temp. Phys. 184(1), 424–430 (2016)

    ADS  Article  Google Scholar 

  14. R. Barends, J.J.A. Baselmans, S.J.C. Yates, J.R. Gao, J.N. Hovenier, T.N. Klapwijk, Quasiparticle relaxation in optically excited high-\(q\) superconducting resonators. Phys. Rev. Lett. 100, 257002 (2008)

    ADS  Article  Google Scholar 

  15. J. Suzuki et al. Journal of low temperature physics ltd17 special issue. (2017) submitted

Download references


This work is supported by Grants-in-Aid for Scientific Research from The Ministry of Education, Culture, Sports, Science, and Technology, Japan (KAKENHI Grant Nos. 25610064, 26105519, 26247045, 14J10972, 15H05448, 15K13491, 15H05743, 16J09435, 16K13809, 16H00874, and 16H01110), by the Center for the Promotion of Integrated Sciences (CPIS) of SOKENDAI, by the FY 2012 Joint Development Research on an Open Application Basis program of the National Astronomical Observatory of Japan (NAOJ), by Research Grants in the Natural Sciences from the Mitsubishi Foundation, and by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (Grant No. 2013R1A1A2004972). We would also like to thank the Advanced Technology Center of NAOJ. We thank David MacDonald, MSc, from Edanz Group ( for editing a draft of this manuscript

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Correspondence to T. Nagasaki.

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Nagasaki, T., Choi, J., Génova-Santos, R.T. et al. GroundBIRD: Observation of CMB Polarization with a Rapid Scanning and MKIDs. J Low Temp Phys 193, 1066–1074 (2018).

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  • Cosmic microwave background
  • Polarization
  • Microwave kinetic inductance detector