Superclusters as future ``island universes'' - the case of Shapley

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We propose a physically motivated definition of superclusters as the largest structures that will remain gravitationally bound as they separate at an exponentially increasing rate in the dark-energy-dominated future of the Universe. Using the spherical collapse model, we were able to analytically determine the condition by which a spherical shell will eventually stop its expansion, becoming the outer limit of a gravitationally bound structure. In particular for the present universe, this criterion states that only shells containing a mean density of 2.36 times the critical density (ρ_c), will eventually stop growing. We tested our criterion using N-body simulations, showing that it gives a good estimate of the external limit of bound structure, and accordingly overestimating its bound mass. The model also showed to give a good estimation of radial velocities up to deep inside the core of the structure. Using this information, we generated a method to estimate the critical shell of structures as seen in redshift space. This method relies in great amount on its calibration using numerical simulations. We applied our method to a large redshift catalog of the Shapley Supercluster, the largest such structure in the nearby Universe (z≤ 0.13), in order to estimate its size and mass. We found that its critical radius is nearly 15h^{-1}Mpc and its mass nearly 7×10^{15}h^{-1}M_{sun}, in good agreement with other studies of the area.

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

Superclusters as future ``island universes'' - the case of Shapley 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 Superclusters as future ``island universes'' - the case of Shapley, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Superclusters as future ``island universes'' - the case of Shapley will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1479179

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