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Lensing of 21-cm Fluctuations by Primordial Gravitational Waves

Book, Laura and Kamionkowski, Marc and Schmidt, Fabian (2012) Lensing of 21-cm Fluctuations by Primordial Gravitational Waves. Physical Review Letters, 108 (21). Art. No. 211301. ISSN 0031-9007.

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Weak-gravitational-lensing distortions to the intensity pattern of 21-cm radiation from the dark ages can be decomposed geometrically into curl and curl-free components. Lensing by primordial gravitational waves induces a curl component, while the contribution from lensing by density fluctuations is strongly suppressed. Angular fluctuations in the 21-cm background extend to very small angular scales, and measurements at different frequencies probe different shells in redshift space. There is thus a huge trove of information with which to reconstruct the curl component of the lensing field, allowing tensor-to-scalar ratios conceivably as small as r∼10^(-9)—far smaller than those currently accessible—to be probed.

Item Type:Article
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URLURL TypeDescription DOIArticle
Kamionkowski, Marc0000-0001-7018-2055
Additional Information:© 2012 American Physical Society. Received 8 December 2011; published 22 May 2012. This work was supported by DoE DE-FG03-92-ER40701, NASA NNX10AD04G, and the Betty and Gordon Moore Foundation.
Group:TAPIR, Moore Center for Theoretical Cosmology and Physics
Funding AgencyGrant Number
Department of Energy (DOE)DE-FG03-92-ER40701
Gordon and Betty Moore FoundationUNSPECIFIED
Issue or Number:21
Classification Code:PACS: 98.62.Sb, 04.30.Tv, 98.70.Vc, 98.80.Es
Record Number:CaltechAUTHORS:20120619-131243430
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:31953
Deposited By: Tony Diaz
Deposited On:20 Jun 2012 21:13
Last Modified:03 Oct 2019 03:56

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