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An acoustic oscillation of the primeval photon-baryon fluid around the decoupling time imprints a characteristic scale in the galaxy distribution today, known as the baryon acoustic oscillation (BAO) scale. Several on-going and/or future galaxy surveys aim at detecting and precisely determining the BAO scale so as to trace the expansion history of the universe. We consider nonlinear and redshift-space distortion effects on the shifts of the BAO scale in $k$-space using perturbation theory. The resulting shifts are indeed sensitive to different choices of the definition of the BAO scale, which needs to be kept in mind in the data analysis. We present a toy model to explain the physical behavior of the shifts. We find that the BAO scale defined as in Percival et al. (2007) indeed shows very small shifts ($lesssim$ 1%) relative to the prediction in {it linear theory} in real space. The shifts can be predicted accurately for scales where the perturbation theory is reliable.
We calculate the non-linear galaxy power spectrum in real space, including non-linear distortion of the Baryon Acoustic Oscillations, using the standard 3rd-order perturbation theory (PT). The calculation is based upon the assumption that the number
We estimate the constraining power of J-PAS for parameters of an interacting dark energy cosmology. The survey is expected to map several millions of luminous red galaxies, emission line galaxies and quasars in an area of thousands of square degrees
Baryon Acoustic Oscillations (BAO) are frozen relics left over from the pre-decoupling universe. They are the standard rulers of choice for 21st century cosmology, providing distance estimates that are, for the first time, firmly rooted in well-under
The baryon acoustic oscillation (BAO) scale acts as a standard ruler for measuring cosmological distances and has therefore emerged as a leading probe of cosmic expansion history. However, any physical effect that alters the length of the ruler can l
The anisotrpy of the redshift space bispectrum $B^s(mathbf{k_1},mathbf{k_2},mathbf{k_3})$, which contains a wealth of cosmological information, is completely quantified using multipole moments $bar{B}^m_{ell}(k_1,mu,t)$ where $k_1$, the length of the