We study the angular power spectra of the polarized component of the Galactic synchrotron emission in the 28 deg^2 test region of the Southern Galactic Plane Survey at 1.4 GHz. These data were obtained by the Australia Telescope Compact Array and allow us to investigate angular power spectra down to arcminute scales. We find that, at this frequency, the polarization spectra for E- and B-modes seem to be affected by Faraday rotation produced in compact foreground screens. A different behavior is shown by the angular spectrum of the polarized intensity PI=(Q^2+U^2)^{1/2}. This is well fitted by a power law (C_{PI,l} ~ l^{-\alpha,PI}) with slope ~1.7, which agrees with higher frequency results and can probably be more confidently extrapolated to the cosmological window.
Polarization Angular Spectra of Galactic Synchrotron Emission on Arcminute Scales
2002
Abstract
We study the angular power spectra of the polarized component of the Galactic synchrotron emission in the 28 deg^2 test region of the Southern Galactic Plane Survey at 1.4 GHz. These data were obtained by the Australia Telescope Compact Array and allow us to investigate angular power spectra down to arcminute scales. We find that, at this frequency, the polarization spectra for E- and B-modes seem to be affected by Faraday rotation produced in compact foreground screens. A different behavior is shown by the angular spectrum of the polarized intensity PI=(Q^2+U^2)^{1/2}. This is well fitted by a power law (C_{PI,l} ~ l^{-\alpha,PI}) with slope ~1.7, which agrees with higher frequency results and can probably be more confidently extrapolated to the cosmological window.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
