Cosmological constraints from the cosmic microwave background

Citation
M. Le Dour et al., Cosmological constraints from the cosmic microwave background, ASTRON ASTR, 364(2), 2000, pp. 369-376
Citations number
68
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY AND ASTROPHYSICS
ISSN journal
0004-6361 → ACNP
Volume
364
Issue
2
Year of publication
2000
Pages
369 - 376
Database
ISI
SICI code
0004-6361(200012)364:2<369:CCFTCM>2.0.ZU;2-2
Abstract
Using an approximate likelihood method adapted to band-power estimates, we analyze the ensemble of first generation cosmic microwave background anisot ropy experiments to deduce constraints over a six-dimensional parameter spa ce describing Inflation-generated adiabatic, scalar fluctuations. The basic preferences of simple Inflation scenarios are consistent with the data set : flat geometries (Omega (tot) equivalent to 1 - Omega (kappa) similar to1) and a scale-invariant primeval spectrum (n similar to 1) are favored. Mode ls with significant negative curvature (Omega (tot) < 0.7) are eliminated, while constraints on postive curvature are less stringent. Degeneracies amo ng the parameters prevent independent determinations of the matter density <Omega>(m), and the cosmological constant ii, and the Hubble constant H-o r emains relatively unconstrained. We also iind that the height of the first Doppler peak relative to the amplitude suggested by data at larger I indica tes a high baryon content (Omega (b)h(2)), almost independently of the othe r parameters. Besides the overall qualitative advance expected of the next generation experiments, their improved dipole calibrations will be particul arly useful for constraining the peak height. Our analysis includes a Goodn ess-of-Fit statistic applicable to power estimates and which indicates that the maximum likelihood model provides an acceptable fit to the data set.