We compare and combine likelihood functions of the cosmological parameters \Omega _ { m } , h and \sigma _ { 8 } from the CMB , type Ia supernovae and from probes of large scale structure .
We include the recent results from the CMB experiments BOOMERANG and MAXIMA-1 .
Our analysis assumes a flat \Lambda CDM cosmology with a scale-invariant adiabatic initial power spectrum .
First we consider three data sets that directly probe the mass in the Universe , without the need to relate the galaxy distribution to the underlying mass via a “ biasing ” relation : peculiar velocities , CMB and supernovae .
We assume a baryonic fraction as inferred from Big-Bang Nucleosynthesis and find that all three data sets agree well , overlapping significantly at the 2 \sigma level .
This therefore justifies a joint analysis , in which we find a joint best fit point and 95 \% confidence limits of \Omega _ { m } = 0.28 ( 0.17 , 0.39 ) , h = 0.74 ( 0.64 , 0.86 ) , and \sigma _ { 8 } = 1.17 ( 0.98 , 1.37 ) .
Secondly we extend our earlier work on combining CMB , supernovae , cluster number counts , IRAS galaxy redshift survey data to include BOOMERANG and MAXIMA-1 data and to allow a free \Omega _ { b } h ^ { 2 } .
We find that , given our assumption of a scale invariant initial power spectrum ( n = 1 ) , we obtain the robust result of \Omega _ { b } h ^ { 2 } = 0.031 \pm 0.03 , which is dominated by the CMB constraint .