MEASUREMENT OF COSMIC MICROWAVE BACKGROUND POLARIZATION POWER SPECTRA FROM TWO YEARS OF BICEP DATA

作者：Chiang H C^*; Ade P A R; Barkats D; Battle J O; Bierman E M; Bock J J; Dowell C D; Duband L; Hivon E F; Holzapfel W L; Hristov V V; Jones W C; Keating B G; Kovac J M; Kuo C L; Lange A E; Leitch E M; Mason P V; Matsumura T; Nguyen H T; Ponthieu N; Pryke C; Richter S; Rocha G; Sheehy C; Takahashi Y D; Tolan J E; Yoon K W

来源：Astrophysical Journal, 2010, 711(2): 1123-1140.

DOI：10.1088/0004-637X/711/2/1123

• cosmic background radiation
• cosmology: observations
• gravitational waves
• inflation
• polarization

Background Imaging of Cosmic Extragalactic Polarization (Bicep) is a bolometric polarimeter designed to measure the inflationary B-mode polarization of the cosmic microwave background (CMB) at degree angular scales. During three seasons of observing at the South Pole (2006 through 2008), Bicep mapped similar to 2% of the sky chosen to be uniquely clean of polarized foreground emission. Here, we present initial results derived from a subset of the data acquired during the first two years. We present maps of temperature, Stokes Q and U, E and B modes, and associated angular power spectra. We demonstrate that the polarization data are self-consistent by performing a series of jackknife tests. We study potential systematic errors in detail and show that they are sub-dominant to the statistical errors. We measure the E-mode angular power spectrum with high precision at 21 <= l <= 335, detecting for the first time the peak expected at l similar to 140. The measured E-mode spectrum is consistent with expectations from a Lambda CDM model, and the B-mode spectrum is consistent with zero. The tensor-to-scalar ratio derived from the B-mode spectrum is r = 0.02(-0.26)(+0.31) or r < 0.72 at 95% confidence, the first meaningful constraint on the inflationary gravitational wave background to come directly from CMB B-mode polarization.

• 出版日期2010-3-10