1. Clusters, Galaxies and the COSMOS J Berian James (IfA Edinburgh), John Peacock, Alexis Finoguenov, Henry Joy McCracken & Gigi Guzzo for the COSMOS collaboration

2. Berian James (IfA Edinburgh) COSMOS – The Cosmic Evolution Survey The primary goal of COSMOS is to study the relationship between large-scale structure and the formation of galaxies, dark matter, and nuclear activity in galaxies. 0.5 < z < 3 2 million objects (I AB ~ 27) Volume ~ SDSS/2dFGRS

3. Berian James (IfA Edinburgh) COSMOS & Large-scale structure  The assembly of galaxies, clusters and dark matter on mass scales up to 10 14 ;  Reconstruction of the dark matter distribution and content at z ~ 1.5;  The redshift and environment evolution of galaxy morphology, merger rates and star formation;  The evolution of AGN and dependence of black hole growth on galaxy morphology and environment; and  The clustering, mass and luminosity distribution of the earliest galaxies, AGN and intergalactic gas at 3 < z < 6. VLA Spitzer HST (ACS) Subaru UKIRT ESO-VLT CHFT NOAO Galex XMM Chandra Scoville et al., astro-ph/0612305

4. Berian James (IfA Edinburgh) Data product: Catalogue of approximately 150 cluster locations, including photometric redshifts. Clusters and galaxy groups VLA Spitzer HST (ACS) Subaru UKIRT ESO-VLT CHFT NOAO Galex XMM Chandra e.g. Finoguenov et al., astro-ph/0612360

5. Berian James (IfA Edinburgh) Optical galaxies  Observations Subaru broad-bands (B, V, r+, i+, z+) Intermediate- and narrow-bands (redshift refinement and high-redshift galaxy search)  Data products Photometric, flux-calibrated images (.05 mag rms) with absolute astrometry (0.1 x ACS pixel) over the full COSMOS field; Million-source photometric redshift catalogue. VLA Spitzer HST (ACS) Subaru UKIRT ESO-VLT CFHT NOAO Galex XMM Chandra e.g. Capak et al., astro-ph/0704.2430

6. Berian James (IfA Edinburgh) The galaxy-cluster cross-correlation

7. Berian James (IfA Edinburgh) Projected cross-correlation function Phleps et al.., A&A 468 113  Decompose the separation into line- of-sight (redshift) and transverse components;  The uncertainties in photometric redshifts cause distortion along line-of-sight;  To remove this effect, integrate along the line-of- sight.

8. Berian James (IfA Edinburgh) The galaxy-cluster cross-correlation  Using 110 clusters at 0.3 < z < 1  Measurement is relative to cluster- random galaxy pairs; the latter reproduces the selection effects of the survey, but is otherwise Poisson- distributed. Separation Correlation amplitude

9. Berian James (IfA Edinburgh) Evolution with mass and redshift  3 redshift bins for 0 < z < 1.0  3 bins in log M from ~10 12 to 10 14  For each bin, measure w p with just the clusters in that bin;  To examine the trend in clustering, compare the amplitude at a fixed value of r p. z increasing M increasing

10. Berian James (IfA Edinburgh) Adaptive binning in the M-z plane  Division of the plane based on clusters available;  For each bin, measure w p with just the clusters in that bin;  Trends not obvious, but can be improved by optimising the number of clusters per bin z M

11. Berian James (IfA Edinburgh) Summary  The cluster-galaxy correlation displays evolution with mass and with redshift;  But at higher redshift, the survey probes higher mass clusters, so how much of the redshift trend is really a trend in mass?  Can adaptive binning simultaneously capture the features of the trends in both mass and redshift?  The generation of random cluster catalogues would go some way to improving the result, by allowing the use of more sophisticated cross- correlation measures.