Angular Power Spectrum of the Microwave Background Anisotropy seen by the COBE Differential Microwave Radiometer
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چکیده
The angular power spectrum estimator developed by Peebles (1973) and Hauser & Peebles (1973) has been modified and applied to the 4 year maps produced by the COBE DMR. The power spectrum of the observed sky has been compared to the power spectra of a large number of simulated random skies produced with noise equal to the observed noise and primordial density fluctuation power spectra of power law form, with P (k) ∝ k. The best fitting value of the spectral index in the range of spatial scales corresponding to spherical harmonic indices 3 ≤ l ∼< 30 is an apparent spectral index napp = 1.13 +0.3 −0.4 which is consistent with the Harrison-Zel’dovich primordial spectral index npri = 1 The best fitting amplitude for napp = 1 is 〈Q 2 RMS〉 0.5 = 18 μK.
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تاریخ انتشار 1994