Nonlinear Structure Formation and the Acoustic Scale

We present high signal-to-noise ratio measurements of the acoustic scalein the presence of nonlinear growth and redshift distortions using 320h^-3 Gpc³ of cosmological particle-meshsimulations. Using simple fitting methods, we obtain robust measurementsof the acoustic scale with scatter close to that predicted by the Fishermatrix. We detect and quantify the shift in the acoustic scale byanalyzing the power spectrum: we detect at greater than 5 σ adecrease in the acoustic scale in the real-space matter power spectrum