A measurement of the cosmic microwave background b-mode polarization power spectrum at sub-degree scales with POLARBEAR
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
We report a measurement of the B-mode polarization power spectrum in the cosmic microwave background (CMB) using the POLARBEAR experiment in Chile. The faint B-mode polarization signature carries information about the universe's entire history of gravitational structure formation, and the cosmic inflation that may have occurred in the very early universe. Our measurement covers the angular multipole range 500 < ℓ < 2100 and is based on observations of an effective sky area of 25 $\deg ^2$ with 3farcm5 resolution at 150 GHz. On these angular scales, gravitational lensing of the CMB by intervening structure in the universe is expected to be the dominant source of B-mode polarization. Including both systematic and statistical uncertainties, the hypothesis of no B-mode polarization power from gravitational lensing is rejected at 97.2% confidence. The band powers are consistent with the standard cosmological model. Fitting a single lensing amplitude parameter ABB to the measured band powers, $A_{BB} = 1.12 \pm 0.61 ({\rm stat}) ^{+0.04}_{-0.12}({\rm sys}) \pm 0.07 ({\rm multi})$, where ABB = 1 is the fiducial WMAP-9 ΛCDM value. In this expression, "stat" refers to the statistical uncertainty, "sys" to the systematic uncertainty associated with possible biases from the instrument and astrophysical foregrounds, and "multi" to the calibration uncertainties that have a multiplicative effect on the measured amplitude ABB.
Date Issued
2014-10-20
Date Acceptance
2014-08-14
Citation
Astrophysical Journal, 2014, 794 (2)
ISSN
0004-637X
Publisher
American Astronomical Society
Journal / Book Title
Astrophysical Journal
Volume
794
Issue
2
Sponsor
Science and Technology Facilities Council (STFC)
Science and Technology Facilities Council [2006-2012]
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000343085800075&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
ST/K001051/1
ST/K001051/1
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
cosmic background radiation
cosmology: observations
large-scale structure of universe
PROBE WMAP OBSERVATIONS
ANGULAR SCALE
GRAVITY-WAVES
UPPER LIMIT
20 GHZ
CMB
EMISSION
MAPS
SUBMILLIMETER
CALIBRATION
Publication Status
Published
Article Number
ARTN 171
Date Publish Online
2014-10-07