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I know that by using Boltzmann equation and all that one can calculate that photons become decoupled around T~3000K and because temperature scales as T~1/a we can determine that the redshift of the CMB is z~1100 since today we observe the CMB temperature as T~2.7K.

Aside from measuring the CMB temperature today and extrapolating, as above, are there other measurements that can be made which determine the redshift of the CMB?

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This redshift can not be measured. It is inferred from a fit to the lambda-CDM model. –  Johannes Jul 18 '13 at 17:51
Which $\Lambda$-CDM parameters are sensitive to the CMB redshift, though? –  user26866 Jul 18 '13 at 21:33
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