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How to extract the "matter fluctuation amplitude" from the CMB power spectrum?

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Quillo
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Translating primordial How to extract the "matter fluctuation amplitude" from the CMB power spectrum to sigma-8

How do you convert the value listed in Planck 2018 results. VI. Cosmological parameters, $A_s = 2.101\times10^{-9}$ to the value of the matter fluctuation amplitude $\sigma_8=0.8111$ given? I tried integrating this in with a growth function D~3400$D\sim 3400$, transfer function (using Eisenstein and Hu), and (realreal-space tophat) window function, but I'm always short of $0.8111$.

Also it seems that the wavenumber with regards to the power spectrum is not normalized by $2\pi$ so that $k_{\rm eq} \sim 0.01 \textrm{ Mpc}^{-1}$. Is it true then that the values given at $k_*=0.05 \textrm{ Mpc}^{-1}$ is within the horizon at matter-radiation equality, $A_s$ is not representative of the spectrum at large scales but somewhat suppressed?

Translating primordial power spectrum to sigma-8

How do you convert the value listed in Planck 2018 results. VI. Cosmological parameters, $A_s = 2.101\times10^{-9}$ to the value of $\sigma_8=0.8111$ given? I tried integrating this in with a growth function D~3400, transfer function (using Eisenstein and Hu), and (real-space tophat) window function, but I'm always short of $0.8111$.

Also it seems that the wavenumber with regards to the power spectrum is not normalized by $2\pi$ so that $k_{\rm eq} \sim 0.01 \textrm{ Mpc}^{-1}$. Is it true then that the values given at $k_*=0.05 \textrm{ Mpc}^{-1}$ is within the horizon at matter-radiation equality, $A_s$ is not representative of the spectrum at large scales but somewhat suppressed?

How to extract the "matter fluctuation amplitude" from the CMB power spectrum

How do you convert the value listed in Planck 2018 results. VI. Cosmological parameters, $A_s = 2.101\times10^{-9}$ to the value of the matter fluctuation amplitude $\sigma_8=0.8111$? I tried integrating this in with a growth function $D\sim 3400$, transfer function (using Eisenstein and Hu), and real-space tophat window function, but I'm always short of $0.8111$.

Also it seems that the wavenumber with regards to the power spectrum is not normalized by $2\pi$ so that $k_{\rm eq} \sim 0.01 \textrm{ Mpc}^{-1}$. Is it true then that the values given at $k_*=0.05 \textrm{ Mpc}^{-1}$ is within the horizon at matter-radiation equality, $A_s$ is not representative of the spectrum at large scales but somewhat suppressed?

The analysis needed is based on the Fourier transform and its power spectrum, as in signal processing (this is why the tags have been added). I added the link to the abstract of the paper
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Quillo
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How do you convert the value listed by Planck 2018,in https://arxiv.org/pdf/1807.06209.pdfPlanck 2018 results. VI. Cosmological parameters, $A_s = 2.101\times10^{-9}$ to the value of $\sigma_8=0.8111$ given? I tried integrating this in with a growth function D~3400, transfer function (using Eisenstein and Hu), and (real-space tophat) window function, but I'm always short of $.8111$$0.8111$.

Also it seems that the wavenumber with regards to the power spectrum is not normalized by $2\pi$ so that $k_{\rm eq} \sim 0.01 \textrm{ Mpc}^{-1}$. Is it true then that the values given at $k_*=0.05 \textrm{ Mpc}^{-1}$ is within the horizon at matter-radiation equality, $A_s$ is not representative of the spectrum at large scales but somewhat suppressed?

How do you convert the value listed by Planck 2018, https://arxiv.org/pdf/1807.06209.pdf, $A_s = 2.101\times10^{-9}$ to the value of $\sigma_8=0.8111$ given? I tried integrating this in with a growth function D~3400, transfer function (using Eisenstein and Hu), and (real-space tophat) window function, but I'm always short of $.8111$.

Also it seems that the wavenumber with regards to the power spectrum is not normalized by $2\pi$ so that $k_{\rm eq} \sim 0.01 \textrm{ Mpc}^{-1}$. Is it true then that the values given at $k_*=0.05 \textrm{ Mpc}^{-1}$ is within the horizon at matter-radiation equality, $A_s$ is not representative of the spectrum at large scales but somewhat suppressed?

How do you convert the value listed in Planck 2018 results. VI. Cosmological parameters, $A_s = 2.101\times10^{-9}$ to the value of $\sigma_8=0.8111$ given? I tried integrating this in with a growth function D~3400, transfer function (using Eisenstein and Hu), and (real-space tophat) window function, but I'm always short of $0.8111$.

Also it seems that the wavenumber with regards to the power spectrum is not normalized by $2\pi$ so that $k_{\rm eq} \sim 0.01 \textrm{ Mpc}^{-1}$. Is it true then that the values given at $k_*=0.05 \textrm{ Mpc}^{-1}$ is within the horizon at matter-radiation equality, $A_s$ is not representative of the spectrum at large scales but somewhat suppressed?

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