The Baryon Acoustic Oscillations (BAO) in the large-scale structure of the
universe leave a distinct peak in the two-point correlation function of the
matter distribution. That acoustic peak is smeared and shifted by bulk flows
and non-linear evolution. However, it has been shown that it is still possible
to sharpen the peak and remove its shift by undoing the effects of the bulk
flows. We propose an improvement to the standard acoustic peak reconstruction.
Contrary to the standard approach, the new scheme has no free parameters,
treats the large-scale modes consistently, and uses optimal filters to extract
the BAO information. At redshift of zero, the reconstructed linear matter power
spectrum leads to a markedly improved sharpening of the reconstructed acoustic
peak compared to standard reconstruction.Comment: 20 pages, 5 figures; footnote adde