Constraining the relative velocity effect using the Baryon Oscillation Spectroscopic Survey

Journal Article · Tue May 16 00:00:00 EDT 2017 · Monthly Notices of the Royal Astronomical Society

DOI:https://doi.org/10.1093/mnras/stx1196· OSTI ID:1389287

Beutler, Florian ^[1]; Seljak, Uroš ^[2]; Vlah, Zvonimir ^[3]

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1. Univ. of Portsmouth (United Kingdom). Inst. of Cosmology and Gravitation
2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States). Dept. of Physics
3. Stanford Univ., CA (United States). Stanford Inst. for Theoretical Physics, Dept. of Physics, Kavli Inst. for Particle Astrophysics and Cosmology

Here, we analyse the power spectrum of the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 to constrain the relative velocity effect, which represents a potential systematic for measurements of the baryon acoustic oscillation (BAO) scale. The relative velocity effect is sourced by the different evolution of baryon and cold dark matter perturbations before decoupling. Our power spectrum model includes all one-loop redshift-space terms corresponding to vbc parametrized by the bias parameter b$$2\atop{v}$$ . We also include the linear terms proportional to the relative density, δbc, and relative velocity dispersion, θbc, which we parametrize with the bias parameters b$$bc\atop{δ}$$ and b$$bc\atop{θ}$$. This data does not support a detection of the relative velocity effect in any of these parameters. Combining the low- and high-redshift bins of BOSS, we find limits of b$$2\atop{v}$$=0.012±0.015(±0.031) , b$$bc\atop{δ}$$=-1.0±2.5(±6.2) and b$$bc\atop{θ}$$=-114±55(±175) with 68 percent (95 percent) confidence levels. These constraints restrict the potential systematic shift in D_A(z), H(z) and fσ8, due to the relative velocity, to 1 percent, 0.8 percent and 2 percent, respectively. Given the current uncertainties on the BAO measurements of BOSS, these shifts correspond to 0.53σ, 0.5σ and 0.22σ for DA(z), H(z) and fσ8, respectively.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-76SF00515
• OSTI ID: 1389287
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 3 Vol. 470; ISSN 0035-8711
• Publisher: Royal Astronomical Society
• Country of Publication: United States
• Language: English

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surveys