Efficient Reconstruction of Linear Baryon Acoustic Oscillations in
  Galaxy Surveys
  Reconstructing an estimate of linear Baryon Acoustic Oscillations (BAO) from
an evolved galaxy field has become a standard technique in recent analyses. By
partially removing non-linear damping caused by bulk motions, the real-space
BAO peak in the correlation function is sharpened, and oscillations in the
power spectrum are visible to smaller scales. In turn these lead to stronger
measurements of the BAO scale. Future surveys are being designed assuming that
this improvement has been applied, and this technique is therefore of critical
importance for future BAO measurements. A number of reconstruction techniques
are available, but the most widely used is a simple algorithm that decorrelates
large-scale and small-scale modes approximately removing the bulk-flow
displacements by moving the overdensity field (Eisenstein et al. 2007;
Padmanabhan, White & Cohn 2009). We consider the practical implementation of
this algorithm, looking at the efficiency of reconstruction as a function of
the assumptions made for the bulk-flow scale, the shot noise level in a random
catalogue used to quantify the mask and the method used to estimate the
bulk-flow shifts. We also examine the efficiency of reconstruction against
external factors including galaxy density, volume and edge effects, and
consider their impact for future surveys. Throughout we make use of the mocks
catalogues created for the Baryon Oscillation Spectroscopic Survey (BOSS) Date
Release 11 samples covering 0.43 < z < 0.7 (CMASS) and 0.15 < z < 0.43 (LOWZ),
to empirically test these changes.
