Cosmic shear statistics in the Suprime-Cam 2.1 sq deg field: Constraints on Omega_m and sigma_8

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

12 pages, 12 figures, accepted for publication in ApJ

Scientific paper

10.1086/378348

We present measurements of the cosmic shear correlation in the shapes of galaxies in the Suprime-Cam 2.1 deg^2 R_c-band imaging data. As an estimator of the shear correlation originated from the gravitational lensing, we adopt the aperture mass variance. We detect a non-zero E mode variance on scales between 2 and 40arcmin. We also detect a small but non-zero B mode variance on scales larger than 5arcmin. We compare the measured E mode variance to the model predictions in CDM cosmologies using maximum likelihood analysis. A four-dimensional space is explored, which examines sigma_8, Omega_m, Gamma and zs (a mean redshift of galaxies). We include three possible sources of error: statistical noise, the cosmic variance estimated using numerical experiments, and a residual systematic effect estimated from the B mode variance. We derive joint constraints on two parameters by marginalizing over the two remaining parameters. We obtain an upper limit of Gamma<0.5 for zs>0.9 (68% confidence). For a prior Gamma\in[0.1,0.4] and zs\in[0.6,1.4], we find sigma_8=(0.50_{-0.16}^{+0.35})Omega_m^{-0.37} for flat cosmologies and sigma_8=(0.51_{-0.16}^{+0.29})Omega_m^{-0.34}$ for open cosmologies (95% confidence). If we take the currently popular LCDM model, we obtain a one-dimensional confidence interval on sigma_8 for the 95.4% level, 0.62<\sigma_8<1.32 for zs\in[0.6,1.4]. Information on the redshift distribution of galaxies is key to obtaining a correct cosmological constraint. An independent constraint on Gamma from other observations is useful to tighten the constraint.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Cosmic shear statistics in the Suprime-Cam 2.1 sq deg field: Constraints on Omega_m and sigma_8 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 Cosmic shear statistics in the Suprime-Cam 2.1 sq deg field: Constraints on Omega_m and sigma_8, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cosmic shear statistics in the Suprime-Cam 2.1 sq deg field: Constraints on Omega_m and sigma_8 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-633266

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.