The following table was taken from Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results, C.L. Bennett et al. (2003), submitted to the Astrophysical Journal; available at http://lambda.gsfc.nasa.gov/

Table 3: "Best" Cosmological Parameters

Description	Symbol	Value	+ uncertainty	- uncertainty
Total density	tot	1.02	0.02	0.02
Equation of state of quintessence	w	< - 0.78	95% CL	--
Dark energy density		0.73	0.04	0.04
Baryon density	b h2	0.0224	0.0009	0.0009
Baryon density	b	0.044	0.004	0.004
Baryon density (cm-3)	nb	2.5 × 10-7	0.1 × 10-7	0.1 × 10-7
Matter density	m h2	0.135	0.008	0.009
Matter density	m	0.27	0.04	0.04
Light neutrino density	h2	< 0.0076	95% CL	--
CMB temperature (K) a	Tcmb	2.725	0.002	0.002
CMB photon density (cm-3) b	n	410.4	0.9	0.9
Baryon-to-photon ratio		6.1 × 10-10	0.3 × 10-10	0.2 × 10-10
Baryon-to-matter ratio	b m-1	0.17	0.01	0.01
Fluctuation amplitude in 8h-1 Mpc spheres	8	0.84	0.04	0.04
Low-z cluster abundance scaling	8 m0.5	0.44	0.04	0.05
Power spectrum normalization (at k0 = 0.05 Mpc-1) c	A	0.833	0.086	0.083
Scalar spectral index (at k0 = 0.05 Mpc-1) c	ns	0.93	0.03	0.03
Running index slope (at k0 = 0.05 Mpc-1) c	dns / d lnk	-0.031	0.016	0.018
Tensor-to-scalar ratio (at k0 = 0.002 Mpc-1)	r	< 0.71	95% CL	--
Redshift of decoupling	zdec	1089	1	1
Thickness of decoupling (FWHM)	zdec	195	2	2
Hubble constant	h	0.71	0.04	0.03
Age of universe (Gyr)	t0	13.7	0.2	0.2
Age at decoupling (kyr)	tdec	379	8	7
Age at reionization (Myr, 95% CL))	tr	180	220	80
Decoupling time interval (kyr)	tdec	118	3	2
Redshift of matter-energy equality	zeq	3233	194	210
Reionization optical depth		0.17	0.04	0.04
Redshift of reionization (95% CL)	zr	20	10	9
Sound horizon at decoupling (°)	A	0.598	0.002	0.002
Angular diameter distance to decoupling (Gpc)	dA	14.0	0.2	0.3
Acoustic scale d	A	301	1	1
Sound horizon at decoupling (Mpc) d	rs	147	2	2
a from COBE (Mather et al., 1999)
b derived from COBE (Mather et al., 1999)
c leff 700
d A A-1   A rs da-1