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arXiv · 2011.07705

GroundBIRD : A CMB polarization experiment with MKID arrays

Kyungmin Lee·Jihoon Choi·Ricardo Tanausú Génova-Santos·Makoto Hattori·Masashi Hazumi·Shunsuke Honda·Takuji Ikemitsu·Hidesato Ishida·Hikaru Ishitsuka·Yonggil Jo·Kenichi Karatsu·Kenji Kiuchi·Junta Komine·Ryo Koyano·Hiroki Kutsuma·Satoru Mima·Makoto Minowa·Joonhyeok Moon·Makoto Nagai·Taketo Nagasaki·Masato Naruse·Shugo Oguri·Chiko Otani·Michael Peel·Rafael Rebolo·José Alberto Rubiño-Martín·Yutaro Sekimoto·Junya Suzuki·Tohru Taino·Osamu Tajima·Nozomu Tomita·Tomohisa Uchida·Eunil Won·Mitsuhiro Yoshida
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Abstract

GroundBIRD is a ground-based experiment for the precise observation of the polarization of the cosmic microwave background (CMB). To achieve high sensitivity at large angular scale, we adopt three features in this experiment: fast rotation scanning, microwave kinetic inductance detector (MKID) and cold optics. The rotation scanning strategy has the advantage to suppress $1/f$ noise. It also provides a large sky coverage of 40\%, which corresponds to the large angular scales of $l \sim 6$. This allows us to constrain the tensor-to-scalar ratio by using low $l$ B-mode spectrum. The focal plane consists of 7 MKID arrays for two target frequencies, 145 GHz and 220 GHz band. There are 161 pixels in total, of which 138 are for 144 GHz and 23 are for 220 GHz. This array is currently under development and the prototype will soon be evaluated in telescope. The GroundBIRD telescope will observe the CMB at the Teide observatory. The telescope was moved from Japan to Tenerife and is now under test. We present the status and plan of the GroundBIRD experiment.

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Kyungmin Lee, Jihoon Choi, Ricardo Tanausú Génova-Santos, Makoto Hattori, Masashi Hazumi, Shunsuke Honda, Takuji Ikemitsu, Hidesato Ishida, Hikaru Ishitsuka, Yonggil Jo, Kenichi Karatsu, Kenji Kiuchi, Junta Komine, Ryo Koyano, Hiroki Kutsuma, Satoru Mima, Makoto Minowa, Joonhyeok Moon, Makoto Nagai, Taketo Nagasaki, Masato Naruse, Shugo Oguri, Chiko Otani, Michael Peel, Rafael Rebolo, José Alberto Rubiño-Martín, Yutaro Sekimoto, Junya Suzuki, Tohru Taino, Osamu Tajima, Nozomu Tomita, Tomohisa Uchida, Eunil Won, Mitsuhiro Yoshida. 2020-11-16. GroundBIRD : A CMB polarization experiment with MKID arrays. https://doi.org/10.1007/s10909-020-02511-5

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