Constraining the baryon-dark matter relative velocity with the large-scale three-point correlation function of the SDSS BOSS DR12 CMASS galaxies
Abstract
We search for a galaxy clustering bias due to a modulation of galaxy number with the baryon-dark matter relative velocity resulting from recombination-era physics. We find no detected signal and place the constraint bv < 0.01 on the relative velocity bias for the CMASS galaxies. This bias is an important potential systematic of baryon acoustic oscillation (BAO) method measurements of the cosmic distance scale using the two-point clustering. Our limit on the relative velocity bias indicates a systematic shift of no more than 0.3 per cent rms in the distance scale inferred from the BAO feature in the BOSS two-point clustering, well below the 1 per cent statistical error of this measurement. This constraint is the most stringent currently available and has important implications for the ability of upcoming large-scale structure surveys such as the Dark Energy Spectroscopic Instrument (DESI) to self-protect against the relative velocity as a possible systematic.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- February 2018
- DOI:
- 10.1093/mnras/stx2723
- arXiv:
- arXiv:1607.06098
- Bibcode:
- 2018MNRAS.474.2109S
- Keywords:
-
- cosmological parameters;
- cosmology: observations;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 7 pages, 2 figures, submitted MNRAS