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Radial Extent of Last Scattering Shell at CMB Recombination

-- | September 19, 2013

Question: At CMB recombination (z=1090), what is the radial extent of the last scattering “shell”?

a) Delta(z) = ….
b) Delta(comoving angular distance)= ….Mpc

The WMAP first-year parameters give Delta(z) = 195. Is this still correct? — Rene

Answer: I think that the Planck results did not change the standard cosmological parameters very much. Therefore, the WMAP value you quote should still be the correct value.

Jeff Mangum

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