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تسجيل مستخدم جديدThe Sunyaev-Zeldovich Effect Spectrum of Abell 2163
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We present an interferometric measurement of the Sunyaev-Zeldovich effect (SZE) at 1 cm for the galaxy cluster Abell 2163. We combine this data point with previous measurements at 1.1, 1.4, and 2.1 mm from the SuZIE experiment to construct the most complete SZE spectrum to date. The intensity in four wavelength bands is fit to determine the central Compton y-parameter (y_c) and the peculiar velocity (v_p) for this cluster. Our results are y_c=3.56(+0.41/-0.41)(+0.27/-0.19) x 10^-4 and v_p=410(+1030/-850)(+460/-440) km/s where we list statistical and systematic uncertainties, respectively, at 68% confidence. These results include corrections for contamination by Galactic dust emission. We find less contamination by dust emission than previously reported. The dust emission is distributed over much larger angular scales than the cluster signal and contributes little to the measured signal when the details of the SZE observing strategy are taken into account.
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