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تسجيل مستخدم جديدTemperature and polarization angular power spectra of Galactic dust radiation at 353 GHz as measured by Archeops
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We present the first measurement of temperature and polarization angular power spectra of the diffuse emission of Galactic dust at 353 GHz as seen by Archeops on 20% of the sky. The temperature angular power spectrum is compatible with that provided by the extrapolation to 353 GHz of IRAS and DIRBE maps using cite{fds} model number 8. For Galactic latitudes $|b| geq 5$ deg we report a 4 sigma detection of large scale ($3leq ell leq 8$) temperature-polarization cross-correlation $(ell+1)C_ell^{TE}/2pi = 76pm 21 murm{K_{RJ}}^2$ and set upper limits to the $E$ and $B$ modes at $11 murm{K_{RJ}}^2$. For Galactic latitudes $|b| geq 10$ deg, on the same angular scales, we report a 2 sigma detection of temperature-polarization cross-correlation $(ell+1)C_ell^{TE}/2pi = 24pm 13 murm{K_{RJ}}^2$. These results are then extrapolated to 100 GHz to estimate the contamination in CMB measurements by polarized diffuse Galactic dust emission. The $TE$ signal is then $1.7pm0.5$ and $0.5pm0.3 murm{K^2_{CMB}}$ for $|b| geq 5$ and 10 deg. respectively. The upper limit on $E$ and $B$ becomes $0.2 murm{K^2_{CMB}} (2sigma)$. If polarized dust emission at higher Galactic latitude cuts is similar to the one we report here, then dust polarized radiation will be a major foreground for determining the polarization power spectra of the CMB at high frequencies above 100 GHz.
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