We analyse the polarized emission at 1.4 GHz in a 3 ^ { \circ } \times 3 ^ { \circ } area at high Galactic latitude ( b \sim - 40 ^ { \circ } ) .
The region , centred in ( \alpha = 5 ^ { h } , \delta = -49 ^ { \circ } ) , 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 the diffuse emission is analysed through the E - and B -mode angular power spectra .
These follow a power law C ^ { X } _ { \ell } \propto \ell ^ { \beta _ { X } } with slopes \beta _ { E } = -1.97 \pm 0.08 and \beta _ { B } = -1.98 \pm 0.07 .
The emission is found to be about a factor 25 fainter than in Galactic plane regions .
The comparison of the power spectra with other surveys indicates that this area is intermediate between strong and negligible Faraday rotation effects .
A similar conclusion can be reached by analysing both the frequency and Galactic latitude behaviors of the diffuse Galactic emission of the 408-1411 MHz Leiden survey data .
We present an analysis of the Faraday rotation effects on the polarized power spectra , and find that the observed power spectra can be enhanced by a transfer of power from large to small angular scales .
The extrapolation of the spectra to 32 and 90 GHz of the CMB window suggests that Galactic synchrotron emission leaves the CMBP E -mode uncontaminated at 32 GHz .
The level of the contamination at 90 GHz is expected to be more than 4 orders of magnitude below the CMBP spectrum .
Extrapolating to the relevant angular scales , this region also appears adequate for investigation of the CMBP B -modes for models with tensor-to-scalar fluctuation power ratio T / S > 0.01 .
We also identify polarized point sources in the field , providing a 9 object list which is complete down to the polarized flux limit of S ^ { p } _ { lim } = 2 mJy .