Limits on CMBP B–Mode Measurements by Galactic Synchrotron Observations
نویسنده
چکیده
The B–Mode of the Cosmic Microwave Background Polarization (CMBP) promises to detect the gravitational wave background left by Inflation and explore this very early period of the Universe. In spite of its importance, however, the cosmic signal is tiny and can be severely limited by astrophysical foregrounds. In this contribution we discuss about one of the main contaminant, the diffuse synchrotron emission of the Galaxy. We briefly report about recent deep observations at high Galactic latitudes, the most interesting for CMB purposes because of the low emission, and discuss the constraints in CMBP investigations. The contamination competes with CMB models with T/S = 10–10, close to the intrinsic limit for a 15% portion of the sky (which is T/S ∼ 10). If confirmed by future surveys with larger sky coverage, this gives interesting perspectives for experiments, that, targeting selected low emission regions, could reach this theoretical limit.
منابع مشابه
Polarized Diffuse Emission at 2.3 GHz in a High Galactic Latitude Area
Polarized diffuse emission observations at 2.3 GHz in a high Galactic latitude area are presented. The 2◦ × 2◦ field, centred in (α = 5, δ = −49◦), is located in the region observed by the BOOMERanG experiment. Our observations has been carried out with the Parkes Radio telescope and represent the highest frequency detection done to date in low emission areas. Because of a weaker Faraday rotati...
متن کاملDeep 1.4-GHz observations of diffuse polarized emission
Polarized diffuse emission observations at 1.4-GHz in a high Galactic latitude area of the northern Celestial hemisphere are presented. The 3.2 × 3.2 field, centred at RA = 1058, Dec = +4218 (B1950), has Galactic coordinates l ∼ 172, b ∼ +63 and is located in the region selected as northern target of the BaR-SPOrt experiment. Observations have been performed with the Effelsberg 100-m telescope....
متن کاملHigh Galactic latitude polarized emission at 1.4 GHz and implications for cosmic microwave background observations
We analyse the polarized emission at 1.4 GHz in a 3◦ × 3◦ area at high Galactic latitude (b ∼ −40◦). The region, centred in (α = 5, δ = −49◦), was observed with the Australia Telescope Compact Array radio-interferometer, whose 3–30 arcmin angular sensitivity range allows the study of scales appropriate for Cosmic Microwave Background Polarization (CMBP) investigations. The angular behavior of t...
متن کاملB–Mode contamination by synchrotron emission from 3-years WMAP data
We study the contamination of the B–mode of the Cosmic Microwave Background Polarization (CMBP) by Galactic synchrotron in the lowest emission regions of the sky. The 22.8-GHz polarization map of the 3-years WMAP data release is used to identify and analyse such regions. Two areas are selected with signal-to-noise ratio S/N < 2 and S/N < 3, covering ∼ 16% and ∼ 26% fraction of the sky, respecti...
متن کاملB-Modes for CMBP Observations
We analyze the instrumental polarization generated by the antenna system (optics and feed horn) due to the unpolarized sky emission. Our equations show that it is given by the convolution of the unpolarized emission map Tb(θ, φ) with a sort of instrumental polarization beam Π defined by the coand cross-polar patterns of the antenna. This result is general, it can be applied to all antenna syste...
متن کامل