Astronomy and Astrophysics – Astrophysics
Scientific paper
1996-05-03
Astronomy and Astrophysics
Astrophysics
MNRAS in press. 12 pages LaTeX including Postscript figures. Uses mn.sty and epsf.sty
Scientific paper
It has been proposed that the cosmological constant $\Lambda$ might be measured from geometric effects on large-scale structure. A positive vacuum density leads to correlation-function contours which are squashed in the radial direction when calculated assuming a matter-dominated model. We show that this effect will be somewhat harder to detect than previous calculations have suggested: the squashing factor is likely to be $<1.3$, given realistic constraints on the matter contribution to $\Omega$. Moreover, the geometrical distortion risks being confused with the redshift-space distortions caused by the peculiar velocities associated with the growth of galaxy clustering. These depend on the density and bias parameters via the combination $\beta\equiv \Omega^{0.6}/b$, and we show that the main practical effect of a geometrical flattening factor $F$ is to simulate gravitational instability with $\beta_{\rm eff}\simeq 0.5(F-1)$. Nevertheless, with datasets of sufficient size it is possible to distinguish the two effects; we discuss in detail how this should be done. New-generation redshift surveys of galaxies and quasars are potentially capable of detecting a non-zero vacuum density, if it exists at a cosmologically interesting level.
Ballinger W. E.
Heavens Alan F.
Peacock John A.
No associations
LandOfFree
Measuring the cosmological constant with redshift surveys 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 Measuring the cosmological constant with redshift surveys, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Measuring the cosmological constant with redshift surveys will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-559572