Gaussian statistics of the cosmic microwave background: Correlation of temperature extrema in the COBE DMR two year sky maps

Aug, 1994
8 pages
Published in:
  • Astrophys.J.Lett. 439 (1995) L29
e-Print:
Report number:
  • COBE-94-15

Citations per year

19952001200720132019012345
Abstract: (arXiv)
We use the two-point correlation function of the extrema points (peaks and valleys) in the COBE Differential Microwave Radiometers (DMR) 2-year sky maps as a test for non-Gaussian temperature distribution in the cosmic microwave background anisotropy. A maximum likelihood analysis compares the DMR data to n=1 toy models whose random-phase spherical harmonic components ama_{\ell m} are drawn from either Gaussian, χ 2\chi~2, or log-normal parent populations. The likelihood of the 53 GHz (A+B)/2 data is greatest for the exact Gaussian model. All non-Gaussian models tested are ruled out at 90\% confidence, limited by type II errors in the statistical inference. The extrema correlation function is a stronger test for this class of non-Gaussian models than topological statistics such as the genus.