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Buzz Bloom
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- TL;DR Summary
- I have been trying to understand the abstract and introduction to the paper
https://arxiv.org/pdf/astro-ph/0501171.pdf
DETECTION OF THE BARYON ACOUSTIC PEAK IN THE LARGE-SCALE CORRELATION FUNCTION OF SDSS LUMINOUS RED GALAXIES.
I made an effort to find in the paper the answers to several questions, but I did not succeed. It may be that the answers could be in papers cited at the end of the article, but I do not have access to the journals cited.
Summary: I have been trying to understand the abstract and introduction to the paper
https://arxiv.org/pdf/astro-ph/0501171.pdf
DETECTION OF THE BARYON ACOUSTIC PEAK IN THE LARGE-SCALE CORRELATION FUNCTION OF SDSS LUMINOUS RED GALAXIES.
I made an effort to find in the paper the answers to several questions, but I did not succeed. It may be that the answers could be in papers cited at the end of the article, but I do not have access to the journals cited.
I would much appreciate any help readers of this thread might be able to provide. Here is a quote (citations omitted) from the introduction that raised the questions in my mind.
Below are the questions.
https://arxiv.org/pdf/astro-ph/0501171.pdf
DETECTION OF THE BARYON ACOUSTIC PEAK IN THE LARGE-SCALE CORRELATION FUNCTION OF SDSS LUMINOUS RED GALAXIES.
I made an effort to find in the paper the answers to several questions, but I did not succeed. It may be that the answers could be in papers cited at the end of the article, but I do not have access to the journals cited.
I would much appreciate any help readers of this thread might be able to provide. Here is a quote (citations omitted) from the introduction that raised the questions in my mind.
Because the universe has a significant fraction of baryons, cosmological theory predicts that the acoustic oscillationsin the plasma will also be imprinted onto the late-time power spectrum of the non-relativistic matter. A simple way to understand this is to consider that from an initial point perturbation common to the dark matter and the baryons, the dark matter perturbation grows in place while the baryonic perturbation is carried outward in an expanding spherical wave. At recombination, this shell is roughly 150 Mpc in radius.
Because the central perturbation in the dark matter is dominant compared to the baryonic shell, the acoustic feature is manifested as a small single spike in the correlation function at 150 Mpc separation.
Below are the questions.
1. What is the standard deviation for this 150 Mpc estimate of the end radius of a propagation spherical shell?
2. What caused the start of each spherical shell of acoustic propagation? (With my limited imagination, I am guessing it was something like an explosion of some sort. How would this relate to a perturbation in density?)
3. At what universe age did these acoustic waves begin?
4. Am I correct that the propagation of these waves ended at the time of recombination (which is the beginning of the CMB)?
5. What were the speeds of propagation at the start and end of propagation?
6. Did the speed of propagation change with changes in temperature and density as related to the scale factor?