Pith. sign in

4-Year COBE DMR Cosmic Microwave Background Observations: Maps and Basic Results

6 Pith papers cite this work. Polarity classification is still indexing.

6 Pith papers citing it
abstract

The cosmic microwave background radiation provides unique constraints on cosmological models. In this Letter we present a summary of the spatial properties of the cosmic microwave background radiation based on the full 4 years of COBE DMR observations, as detailed in a set of companion Letters. The anisotropy is consistent with a scale-invariant power law model and Gaussian statistics. With full use of the multi-frequency 4-year DMR data, including our estimate of the effects of Galactic emission, we find a power-law spectral index of $n=1.2\pm 0.3$ and a quadrupole normalization $Q_{rms-PS}=15.3^{+3.8}_{-2.8}$ $\mu$K. For $n=1$ the best-fit normalization is $Q_{rms-PS}\vert_{n=1}=18\pm 1.6$ $\mu$K. These values are consistent with both our previous 1-year and 2-year results. The results include use of the $\ell=2$ quadrupole term; exclusion of this term gives consistent results, but with larger uncertainties. The 4-year sky maps, presented in this Letter, portray an accurate overall visual impression of the anisotropy since the signal-to-noise ratio is ~2 per 10 degree sky map patch. The improved signal-to-noise ratio of the 4-year maps also allows for improvements in Galactic modeling and limits on non-Gaussian statistics.

citation-role summary

background 4

citation-polarity summary

roles

background 4

polarities

background 4

representative citing papers

Forecasts of CMB $E$-mode anomalies for AliCPT-1

astro-ph.CO · 2026-04-22 · conditional · novelty 6.0

A divide-and-conquer framework using QAOA and neural network surrogates accelerates constrained MCMC by factors of 7.6 to 20.3 over classical methods.

citing papers explorer

Showing 6 of 6 citing papers.