Cosmic microwave weak lensing data as a test for the dark universe

Calabrese, Erminia ORCID: https://orcid.org/0000-0003-0837-0068, Slosar, Anze, Melchiorri, Alessandro, Smoot, George F. and Zahn, Oliver 2008. Cosmic microwave weak lensing data as a test for the dark universe. Physical Review D 77 (12) , 123531. 10.1103/PhysRevD.77.123531

Preview

PDF - Published Version Download (404kB) | Preview

Abstract

Combined analyses of WMAP 3-year and ACBAR cosmic microwave anisotropies angular power spectra have presented evidence for gravitational lensing at >3� level. This signal could provide a relevant test for cosmology. After evaluating and confirming the statistical significance of the detection in light of the new WMAP 5-year data, we constrain a new parameter AL that scales the lensing potential such that AL ¼ 0 corresponds to unlensed while AL ¼ 1 is the expected lensed result in the standard �-CDM model. We find from WMAP5 þ ACBAR a 2:5� indication for a lensing contribution larger than expected, with AL ¼ 3:1þ1:8 �1:5 at 95% C.L. The result is stable under the assumption of different templates for an additional Sunyaev-Zel’dovich foreground component or the inclusion of an extra background of cosmic strings. We find negligible correlation with other cosmological parameters as, for example, the energy density in massive neutrinos. While unknown systematics may be present, dark energy or modified gravity models could be responsible for the over-smoothness of the power spectrum. Near-future data, most notably from the Planck satellite mission, will scrutinize this interesting possibility.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Physics and Astronomy
Subjects:	Q Science > QB Astronomy
Publisher:	American Physical Society
ISSN:	1550-7998
Date of First Compliant Deposit:	10 October 2017
Date of Acceptance:	13 March 2008
Last Modified:	06 May 2023 06:01
URI:	https://orca.cardiff.ac.uk/id/eprint/105358

Citation Data

Cited 111 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item