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The Polatron: A Millimeter-Wave Cosmic Microwave Background Polarimeter for the OVRO 5.5 m Telescope

B. J. Philhour·B. G. Keating·P. A. R. Ade·R. S. Bhatia·J. J. Bock·S. E. Church·J. Glenn·J. R. Hinderks·V. V. Hristov·W. C. Jones·M. Kamionkowski·D. E. Kumar·A. E. Lange·J. R. Leong·D. P. Marrone·B. S. Mason·P. V. Mason·M. M. Shuman·G. I. Sirbi
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Abstract

We describe the development of a bolometric receiver designed to measure the arcminute-scale polarization of the cosmic microwave background (CMB). The Polatron will be mounted at the Cassegrain focus of the 5.5 m telescope at the Owens Valley Radio Observatory (OVRO). The receiver will measure both the Q and U Stokes parameters over a 20% pass-band centered near 100 GHz, with the input polarization signal modulated at ~0.6 Hz by a rotating, birefringent, quartz half-wave plate. In six months of observation we plan to observe ~400 2.5 arcminute pixels in a ring about the North Celestial Pole to a precision of ~6 μK/pixel in each of Q and U, adequate to unambiguously detect CMB polarization at levels predicted by current models.

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B. J. Philhour, B. G. Keating, P. A. R. Ade, R. S. Bhatia, J. J. Bock, S. E. Church, J. Glenn, J. R. Hinderks, V. V. Hristov, W. C. Jones, M. Kamionkowski, D. E. Kumar, A. E. Lange, J. R. Leong, D. P. Marrone, B. S. Mason, P. V. Mason, M. M. Shuman, G. I. Sirbi. 2001-06-28. The Polatron: A Millimeter-Wave Cosmic Microwave Background Polarimeter for the OVRO 5.5 m Telescope. https://arxiv.org/abs/astro-ph/0106543

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