@article {632941, title = {Analysing baryon acoustic oscillations in sparse spectroscopic samples via cross-correlation with dense photometry}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {477}, year = {2018}, month = {July 1, 2018}, pages = {5090-5103}, abstract = {We develop a formalism for measuring the cosmological distance scalefrom baryon acoustic oscillations (BAO) using the cross-correlation of asparse redshift survey with a denser photometric sample. This reducesthe shot noise that would otherwise affect the autocorrelation of thesparse spectroscopic map. As a proof of principle, we make the firston-sky application of this method to a sparse sample defined as the z> 0.6 tail of the Sloan Digital Sky Survey{\textquoteright}s (SDSS) BOSS/CMASS sampleof galaxies and a dense photometric sample from SDSS DR9. We find a2.8σ preference for the BAO peak in the cross-correlation at aneffective z = 0.64, from which we measure the angular diameter distanceDM(z = 0.64) = (2418 {\textpm} 73 Mpc)(rs/rs,fid). Accordingly, we expect that using this method to combinesparse spectroscopy with the deep, high-quality imaging that is just nowbecoming available will enable higher precision BAO measurements thanpossible with the spectroscopy alone.}, keywords = {distance scale; large-scale structure of Universe}, isbn = {0035-8711}, url = {http://adsabs.harvard.edu/abs/2018MNRAS.477.5090P}, author = {Patej, A. and Eisenstein, D. J.} }