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trinitree88
2011-Jul-15, 02:58 PM
The sound waves from the BB are purported to be evident in the position and strength of the first and successive acoustic peaks in the CMB. Deviations from intial WMAP projections of these acoustic peaks possibly mean deviations in cosmological models of the same. The authors, Shanks and Sawangwit, having found some discrepancies in an earlier paper, use the Early Release Planck Data, to firm up their concerns, and put out a new paper on calibration techniques of WMAP and Planck, along with additional author Whitbourn.
SEE:http://arxiv.org/PS_cache/arxiv/pdf/1107/1107.2654v1.pdf


acoustic peak....SEE: http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation

antoniseb
2011-Jul-16, 12:35 AM
I saw the paper. Interesting. We'll see where Planck puts these cosmological parameters.

trinitree88
2011-Jul-16, 12:53 PM
I saw the paper. Interesting. We'll see where Planck puts these cosmological parameters.

antoniseb. Yep. I expect different instrumentation will show some new features, but I don't think they'll throw the baby out with the bath water. pete

Tensor
2011-Jul-19, 05:20 AM
The sound waves from the BB are purported to be evident in the position and strength of the first and successive acoustic peaks in the CMB. Deviations from intial WMAP projections of these acoustic peaks possibly mean deviations in cosmological models of the same. The authors, Shanks and Sawangwit, having found some discrepancies in an earlier paper, use the Early Release Planck Data, to firm up their concerns, and put out a new paper on calibration techniques of WMAP and Planck, along with additional author Whitbourn.
SEE:http://arxiv.org/PS_cache/arxiv/pdf/1107/1107.2654v1.pdf

The problem I have with this, at the moment, is encapsulated in the following:
Although, the corresponding temperature maps from which these were estimated have not been released, both radio source fluxes and SZ profile parameters are available as measured by Planck. We can therefore use these to compare WMAP and Planck radio source fluxes directly and also to make WMAP stacks centred now on the new radio source and SZ cluster lists from Planck. From these stacks, the WMAP beam profile can be inferred and the SZ results from WMAP and Planck compared.

While I can buy the direct comparison of the SZ and flux results (which give some interesting anomalies to figure out), the rest of the paper, being dependent on the assumptions and inferences used to recreate the beam profile to compare to temp maps, is a bit shakier. I'd like to see how the comparison stands up, once the maps are released.