The clustering of galaxy groups in the 2dFGRS (2PIGG)

The clustering of 2PIGGs

Project zero: CDM predictions and parameter constraints

Project one, two,..: Other uses of the clustering of 2PIGG

Network-wide project again!

Outline:

Clustering dependence on group mass from the 2PIGG

Clustering dependence on group mass from the 2PIGG

2PIGG Subsamples:

Padilla & the 2dFGRS Team – Astro-ph/0402577

Indicators of amplitude of clustering:

Relative bias:

s) = b2 ’(s)

Padilla & the 2dFGRS Team – Astro-ph/0402577

Clustering dependence on group mass from the 2PIGG

Clustering length:

(s0) = 1

Indicators of amplitude of clustering:

Clustering dependence on group mass from the 2PIGG

Clustering dependence on group mass:

Comparison withother cluster results

Padilla & the 2dFGRS Team – Astro-ph/0402577

Project zero: CDM predictions and parameter constraints

Clustering dependence on

group mass: Comparison with

CDM

Clustering dependence on group mass: CDM predictions

mh0

h0

b/m

8

v

1. Choose mh0 and h0. Calculate = 1 - m

2. Calculate dc using luminosity function and geometry

3. Pick b/m

4. Calculate linear mass power spectrum Plin,mass(k)

5. Choose value of 8

6. Calculate b(M), n(M), dc, theory(M) dc, theory(b) or b(dc, theory)

7. Choose v

8. Choose dc

9. Calculate non-linear halo power spectrum Pnl,halo(ks) for this dc

10. Fourier transform power spectrum nl,halo(s) s0,theory

Model predictions for dc-s0

Padilla & Baugh, MNRAS, 2002, 329, 431.

Clustering dependence on group mass: CDM predictions

6/6. Cosmology

Reference model:

mh0=0.21

h0=0.7

b/m=0.2

8=0.95

v=3.5

dc-s0 for 2PIGG Constraints

Clustering dependence on group mass: Constraints from s0

6/6. Cosmology

mh0 b/m

8 v/100kms-1

Clustering dependence on group mass: Constraints from s0

6/6. Cosmology

mh mh

Percival et al. 2002

Project one: matching the clustering of groups with non-gaussian initial fluctuations

Project two: use non-gaussian simulations to studyhigher order correlations and compare to

results from the 2dFGRS

NETWORK-WIDE PROJECT

Telescopes:

ESO: Paranal and La Silla

CTIO

GEMINI

CARNEGIE: Magellan Las Campanas