Nonnucleosynthetic constraints on the Baryon density and other cosmological parameters

Because the baryon-to-photon ratio eta(10) is in some; doubt, we drop nucle osynthetic constraints on eta(10) and fit the three cosmological parameters (h, Omega(M), eta(10)) to four observational constraints: Hubble parameter h(o) = 0.70 +/- 0.15, age of the universe t(o) = 14(-2)(+7) Gyr, cluster g as fraction f(o) = f(G) h(3/2) = 0.060 +/- 0.006, and effective shape param eter Gamma(o) = 0.255 +/- 0.017. Errors quoted are 1 sigma, and we assume G aussian statistics. We experiment with a fifth constraint Omega(o) = 0.2 0.1. from clusters. We set the tilt parameter n = 1 and the gas enhancement factor Y = 0.9. We consider cold dark matter models (open and Omega(M) = 1 ) and hat Lambda CDM models. We omit HCDM models (tu which the Gamma(o) con straint does not apply). We test goodness of fit and draw confidence region s by the Delta chi(2) method. CDM models with Omega(M) = 1 (SCDM models) ar e accepted only because the large error on h, allows h < 0.5. Baryonic matt er plays a significant role in Gamma(o) when Omega(M) similar to 1. Open CD M models are accepted only for Omega(M) greater than or similar to 0.4. The combination of the four other constraints with Omega(o) approximate to 0.2 is rejected in CDM models with 98% confidence, suggesting that light may n ot trace mass. Lambda CDM models give similar results. In all of these mode ls, eta(10) greater than or similar to 6 is favored strongly over eta(10) l ess than or similar to 2. This suggests that reports of low deuterium abund ances-on QSO lines df sight may be correct and that observational determina tions of primordial He-4 may have systematic errors. Plausible variations o n n and Y in our models do not change the results much. If we drop or chang e thecal Gamma(o) constraint, lower values of Omega(M) and eta(10) are perm itted. The constraint Gamma(o) = 0.15 +/- 0.04, derived recently from the I RAS redshift survey, favors Omega(M) approximate to 0.3 and eta(10) approxi mate to 5 but does not exclude eta(10) approximate to 2.