Bibcode
Hancock, S.; Rocha, G.; Lasenby, A. N.; Gutierrez, C. M.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, vol. 294, p. L1-L6
Advertised on:
2
1998
Citations
107
Refereed citations
91
Description
We present new results from a study of recent cosmic microwave
background (CMB) observations which provide the first strong evidence
for the existence of a 'Doppler peak' localized in both angular scale
and amplitude. This first estimate of the angular position of the peak
is used to place a new direct limit on the curvature of the universe,
corresponding to a density of Omega = 0.7 +0.8, -0.5, consistent with a
flat universe. Very low-density 'open' universe models are inconsistent
with this limit unless there is a significant contribution from a
cosmological constant. For a flat standard cold dark matter dominated
universe we use our results in conjunction with big bang nucleosynthesis
constraints to determine the value of the Hubble constant as H0 = 30-70
km/s Mpc for baryon fractions Omega(b) = 0.05 to 0.2. For H0 = 50 km/s
Mpc we find the primordial spectral index of the fluctuations to be n =
1.1 +/- 0.1, in close agreement with the inflationary prediction of n of
about 1.0.