Search Swinburne Research Bank
Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/225008
- Improving measurements of H(z) and D A(z) by analysing clustering anisotropies
- Kazin, Eyal A.; Sanchez, Ariel G.; Blanton, Michael R.
- The baryonic acoustic feature in galaxy clustering is a promising tool for constraining the nature of the cosmic acceleration, through measurements of expansion rates H and angular diameter distances DA. Angle-averaged measurements of clustering yield constraints on the quantity D_A^2/H. However, to break the degeneracy between these two parameters one must measure the anisotropic clustering as a function of both line-of-sight (radial) and transverse separations. Here we investigate how to most effectively do so, using analytic techniques and mock catalogues. In particular, we examine multipole expansions of the correlation function and introduce 'clustering wedges'ξ(Δμ, s), where μ=s∥/s and s∥ is the radial component of separation s. Both techniques allow strong constraints on H and DA, as expected. The radial wedges strongly depend on H and the transverse wedges are sensitive to DA. When analysing the full shape of ξ, we find similar constraints when using the clustering wedges and the monopole-quadrupole pair. We find additional improvement when using the hexadecapole, as previously mentioned in the literature. Our findings here demonstrate that wedge statistics provide a practical alternative technique to multipoles, which should be useful to test systematics and will provide comparable constraints.
- Publication type
- Journal article
- Monthly Notices of the Royal Astronomical Society, Vol. 419, no. 4 (Feb 2012), pp. 3223-3243
- Publication year
- FOR Code(s)
- 0201 Astronomical and Space Sciences
- Cosmological parameters; Distance scale; Large-scale structure of Universe
- Publisher URL
- Copyright © 2011 The Authors. Journal compilation copyright © 2011 Royal Astronomical Society.
- Peer reviewed