Dark Energy from Large-Scale Structure Lensing Information

Details Dark Energy from Large-Scale Structure Lensing Information Dark Energy from Large-Scale Structure Lensing Information

2009-05-04

arxiv.org/abs/0905.0499v1

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

submitted to PRD

Scientific paper

Wide area Large-Scale Structure (LSS) surveys are planning to map a substantial fraction of the visible universe to quantify dark energy through Baryon Acoustic Oscillations (BAO). At increasing redshift, for example that probed by proposed 21-cm intensity mapping surveys, gravitational lensing potentially limits the fidelity (Hui et al., 2007) because it distorts the apparent matter distribution. In this paper we show that these distortions can be reconstructed, and actually used to map the distribution of intervening dark matter. The lensing information for sources at z=1-3 allows accurate reconstruction of the gravitational potential on large scales, l <~ 100, which is well matched for Integrated Sachs-Wolfe (ISW) effect measurements of dark energy and its sound speed, and a strong constraint for modified gravity models of dark energy. We built an optimal quadratic lensing estimator for non-Gaussian sources, which is necessary for LSS. The phenomenon of "information saturation" (Rimes & Hamilton, 2005) saturates reconstruction at mildly non-linear scales, where the linear source power spectrum Delta^2 ~ 0.2-0.5. We find that steeper power spectra, saturate more quickly. We compute the effective number densities of independent lensing sources for LSS lensing, and find that they increase rapidly with redshifts. For LSS/21-cm sources at z ~ 2-4, the lensing reconstruction is limited by cosmic variance at l<~ 100.

Affiliated with

Also associated with

No associations

Rating

Dark Energy from Large-Scale Structure Lensing Information does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Dark Energy from Large-Scale Structure Lensing Information, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dark Energy from Large-Scale Structure Lensing Information will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-449953