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arXiv · 1408.4788

CLASS: The Cosmology Large Angular Scale Surveyor

Thomas Essinger-Hileman·Aamir Ali·Mandana Amiri·John W. Appel·Derek Araujo·Charles L. Bennett·Fletcher Boone·Manwei Chan·Hsiao-Mei Cho·David T. Chuss·Felipe Colazo·Erik Crowe·Kevin Denis·Rolando Dünner·Joseph Eimer·Dominik Gothe·Mark Halpern·Kathleen Harrington·Gene Hilton·Gary F. Hinshaw·Caroline Huang·Kent Irwin·Glenn Jones·John Karakla·Alan J. Kogut·David Larson·Michele Limon·Lindsay Lowry·Tobias Marriage·Nicholas Mehrle·Amber D. Miller·Nathan Miller·Samuel H. Moseley·Giles Novak·Carl Reintsema·Karwan Rostem·Thomas Stevenson·Deborah Towner·Kongpop U-Yen·Emily Wagner·Duncan Watts·Edward Wollack·Zhilei Xu·Lingzhen Zeng
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Abstract

The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to measure the signature of a gravita-tional-wave background from inflation in the polarization of the cosmic microwave background (CMB). CLASS is a multi-frequency array of four telescopes operating from a high-altitude site in the Atacama Desert in Chile. CLASS will survey 70\% of the sky in four frequency bands centered at 38, 93, 148, and 217 GHz, which are chosen to straddle the Galactic-foreground minimum while avoiding strong atmospheric emission lines. This broad frequency coverage ensures that CLASS can distinguish Galactic emission from the CMB. The sky fraction of the CLASS survey will allow the full shape of the primordial B-mode power spectrum to be characterized, including the signal from reionization at low $\ell$. Its unique combination of large sky coverage, control of systematic errors, and high sensitivity will allow CLASS to measure or place upper limits on the tensor-to-scalar ratio at a level of $r=0.01$ and make a cosmic-variance-limited measurement of the optical depth to the surface of last scattering, $\tau$.

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Thomas Essinger-Hileman, Aamir Ali, Mandana Amiri, John W. Appel, Derek Araujo, Charles L. Bennett, Fletcher Boone, Manwei Chan, Hsiao-Mei Cho, David T. Chuss, Felipe Colazo, Erik Crowe, Kevin Denis, Rolando Dünner, Joseph Eimer, Dominik Gothe, Mark Halpern, Kathleen Harrington, Gene Hilton, Gary F. Hinshaw, Caroline Huang, Kent Irwin, Glenn Jones, John Karakla, Alan J. Kogut, David Larson, Michele Limon, Lindsay Lowry, Tobias Marriage, Nicholas Mehrle, Amber D. Miller, Nathan Miller, Samuel H. Moseley, Giles Novak, Carl Reintsema, Karwan Rostem, Thomas Stevenson, Deborah Towner, Kongpop U-Yen, Emily Wagner, Duncan Watts, Edward Wollack, Zhilei Xu, Lingzhen Zeng. 2014-08-20. CLASS: The Cosmology Large Angular Scale Surveyor. https://doi.org/10.1117/12.2056701

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