Title: Superclusters%20as%20future%20
1Superclusters as future island universes
the case of Shapley
- Andreas Reisenegger
- PUC / ESO
Theory/simulations Rolando Dünner (PUC) Andrés
Meza (UChile/UNAB) Pablo A. Araya (Groningen)
Observations Hernán Quintana (PUC) Dominique
Proust (Meudon) E. Rodrigo Carrasco (Gemini)
several others
2Outline
- Superclusters, Shapley
- Superclusters?
- Future of structure in ?CDM cosmology
- Spherical collapse, gravitational binding
- Redshift-space appearance
- Supercluster boundaries masses
- Future plans
3F
2MASS Galactic chart
4Shapley Supercluster Redshift catalog of Proust
et al. 2006
5Shapley Supercluster Redshift catalog of Proust
et al. 2006
6(No Transcript)
7Superclusters?
- What is a supercluster?
- What are its boundaries?
- So far, definitions have been
- Vague agglomeration of galaxies or clusters, or
- Arbitrary some overdensity, or
- Very technical largest non-percolating
structures. - NOT physical
8?CDM Cosmology
- Initially matter-dominated
- hierarchical growth of structure
- up to clusters of galaxies (so far)
- Now, ? is taking over
- expansion accelerates! (supernovae)
- bound structures separate from each other
- structure formation stops
- Some structures are dense enough to locally
dominate over ?, but not yet virialized - will collapse within the next Hubble time or so
- largest bound structures in the Universe
- physical definition of superclusters
9Pablo A. Araya, PhD Thesis (Groningen), in
preparation
10Present (a1)
Distant future (a100)
Pablo A. Araya, PhD Thesis (Groningen), in
preparation
11Spherical model
- Equation of motion for a mass shell
- Analytical solution for the critical
(marginally bound) shell (Dünner et al. 2006,
MNRAS, 366, 803)
12Spherical overdensity criterion vs. simulations
Dünner et al. 2006
13Radial velocity profile
Dünner et al. 2006
14Real space vs. redshift space
Dünner et al., submitted (astro-ph/0611435)
15Bound structures in redshift space
- Radial velocity from
- true density profile (solid)
- NFW density profile (dashed)
- simulation (dots boundgreen, unboundblue)
Velocity envelopes derived through spherical
collapse from density profiles of simulated
structures
Dünner et al., submitted (astro-ph/0611435)
16Redshift-space boundary
- Shape is velocity envelope from
- True density profile (black, solid)
- NFW profile spherical collapse (dashed, red
green) - Calibrate redshift-space density through
simulations to be able to fit to observed data
Dünner et al., submitted (astro-ph/0611435)
17The boundaries of Shapley
Dünner et al., in preparation
18Supercluster masses
Pablo A. Araya, PhD Thesis (Groningen), in
preparation
Dünner et al., in preparation
19Near future
- Verify spherical collapse model through Dn-?
distances to individual clusters in Shapley
(Magellan proposal Quintana, Reisenegger,
Melnick, Selman, ...). - Claimed disagreement of predicted vs. observed
supercluster mass function (Einasto et al. 2006)
verify through redshift-space analysis of
simulations vs. SDSS or 2dFGRS. - Improve compare mass determination methods in
simulations in Shapley. - Center for the Exploration of Superclusters of
Galaxies (CESGA) Milenio proposal, in 2nd
round of evaluation.