A potentially pure test of cosmic geometry: galaxy clusters and the real space Alcock-Paczynski test

Details A potentially pure test of cosmic geometry: galaxy clusters and the real space Alcock-Paczynski test A potentially pure test of cosmic geometry: galaxy clusters and the real space Alcock-Paczynski test

2006-10-10

arxiv.org/abs/astro-ph/0610294v1

Mon.Not.Roy.Astron.Soc.374:535-546,2007

Astronomy and Astrophysics

Astrophysics

13 pages, 15 figures, Monthly Notices in press

Scientific paper

10.1111/j.1365-2966.2006.11168.x

We investigate the possibility of probing dark energy by measuring the isotropy of the galaxy cluster autocorrelation function (an Alcock-Paczynski test). The correlation function is distorted in redshift space because of the cluster peculiar velocities, but if these are known and can be subtracted, the correlation function measurement becomes in principle a pure test of cosmic geometry. Galaxy cluster peculiar velocities can be measured using the kinetic Sunyaev Zel'dovich (kSZ) effect. Upcoming CMB surveys, e.g., ACT, SPT, Planck, are expected to do this with varying levels of accuracy, dependent on systematic errors due to cluster temperature measurements, radio point sources, and the primary CMB anisotropy. We use the Hubble volume N-body simulation and the hydrodynamic simulation results of Nagai et. al (2003) to simulate various kSZ surveys. We find by model fitting that a measurement of the correlation function distortion can be used to recover the cosmological parameters that have been used to generate the simulation. However, the low space density of galaxy clusters requires larger surveys than are taking place at present to place tight constraints on cosmology. For example, with the SPT and ACT surveys, Omega_Lambda could be measured to within 0.1 and 0.2 respectively at one sigma, but only upper limits on the equation of state parameter w will be possible. Nevertheless, with accurate measurements of the kSZ effect, this test can eventually be used to probe the dark energy equation of state and its evolution with redshift, with different systematic errors than other methods.

Affiliated with

Also associated with

No associations

Rating

A potentially pure test of cosmic geometry: galaxy clusters and the real space Alcock-Paczynski test 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 A potentially pure test of cosmic geometry: galaxy clusters and the real space Alcock-Paczynski test, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A potentially pure test of cosmic geometry: galaxy clusters and the real space Alcock-Paczynski test will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-437295