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Cluster Lenses & High Redshift Clusters (MACS) A Status Report. Jean-Paul KNEIB Observatoire Astronomique Marseille Provence , Marseille, France
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Cluster Lenses & High Redshift Clusters (MACS)A Status Report Jean-Paul KNEIB Observatoire Astronomique Marseille Provence, Marseille, France H. Ebeling, G. Smith, A. Gal-Yam, I. Smail, A. Edge, J. Greene, P. Hudelot, S. Bardeau, G. Soucail, P. Marshall, E. Egami, G. Covone, E.Jullo and many others
Outline • Lensing in Clusters • Mass Distribution in Cluster: strong & weak lensing at low-z • MACS Clusters (0.3<z<0.8): • ACS deep survey • MACS Snapshot, RXJ0152 • (SN search) • Future prospects Ringberg, Hi-z clusters
Theory: Lens Diagram CFHT BRI 1990 Z_cluster=0.375 Z_arc=0.725 (Soucail et al 1988) Ringberg, Hi-z clusters
Science with Cluster Lenses • Study the mass distribution of cluster => cosmology? • Study the distant lensed Universe • Direct constrain on cosmological parameters Ringberg, Hi-z clusters
Theory: Lens Mapping a The lensing equation is a mapping from image plane to source plane: q - b = Dls/Ds. a = Dls/Ds df/dq For a point mass, the deflection angle is: a = 4GM/bc2 (b is the impact parameter) -> typically 10” for a 1014 Solar mass Amplification matrix: Ringberg, Hi-z clusters
Cluster Lenses • Insensitive to: • Nature of matter • Physical state of matter • Cleanest available probe of Dark Matter Strong Lensing in the core, Weak lensing on large scale Most massive clusters Einstein radius: 10-45” Ned Wrigth, UCLA Ringberg, Hi-z clusters
Mass distribution in cluster cores Ringberg, Hi-z clusters
Cluster Lens: Mass Reconstruction • Parameterized mass distribution, involving various multiple image system (works better, less free parameters) • Need to include galaxy scale mass components • using scaling relations (dominate locally the mass) Ringberg, Hi-z clusters
Strong and Weak Lensing Absolute central mass relative total mass and slope Ringberg, Hi-z clusters
An Example from space:Cl0024+1654 HST wide field sparse mosaic • 76 orbits, 38 pointings • Probe regions up to ~5Mpc • Aim: learn cluster physics of clusters by comparing with other mass estimates: X-ray, dynamics (Treu et al 2003, Kneib et al 2003) Ringberg, Hi-z clusters
0024: Shear Profile SIS fitting strong lensing data • Extrapolate strong lensing models at large scale by exploring various cluster mass profile. • Rule out SIS model • NFW (with large c~20) or Power-law models give comparatively good model. NFW fitting strong And weak lesning ~3 Mpc Ringberg, Hi-z clusters
Mass traces Light !!! Cl0024: Mass vs. Light • NFW and Power-Law model fit the strong+weak lensing • But high concentration compared to expectations • (similar results on other clusters: A1689 …) • SIS does not fit the strong+weak lensing • M/L is constant with radius with M/LK~40 Red sequence selection Light profile NFW model Broader sequence selection SIS model fitting weak lensing Kneib et al 2003 Ringberg, Hi-z clusters
Questions for Cluster Physics • What are the total mass and structural properties of massive clusters? • How are the mass and structure of clusters related to the global thermodynamics (Tx, Lx)? • How do cluster substructure and thermodynamics evolve with redshift? • Implications of cluster mass and substructure for cluster Cosmology? Ringberg, Hi-z clusters
Multi-wavelength/epoch study Dt~2Gyr 2Gyr 2Gyr • z=0.21+/-0.04 • Lx>8x1044erg/s A68 A209 A267 A383 A773 A963 Ellis et al. 1991 A1763 A1835 A2218 Kneib et al. 1996 A2219 Smail et al. 1995 • Study of 10 clusters at z~0.2 • HST, WFPC2, F702W, 75ksec • Chandra, ACIS-I(S), 4-40ksec • UKIRT, UFTI, 9ksec • CFHT12k, BRI, weak shear X-ray Luminosity z=0 z=0.2 z=0.5 z~1 Ringberg, Hi-z clusters
Triply-imaged “ERO” R-K=5.4 z=1.6 Smith et al 2001,2003,2005 Example:Abell 68 (z=0.25) Data and constraints • ID multiple image systems (HST) • Spectroscopic redshifts (Keck+) • Weak lensing constraints (HST) Measurements • Cluster mass (R<500kpc) • Dark matter morphology Ringberg, Hi-z clusters
Atypical Unrelaxed Quantitative structural classification Typical Unrelaxed Relaxed Smith et al., 2005 Mass [Lensing] Ndm1 2 1 Mcen/Mtot0.97±0.01 0.77±0.01 0.96±0.01 Ttot/Tann0.8±0.1 1.0±0.1 1.0±0.2 Δr (arcsec) <1 10±2 22±1 ICM [X-ray] • 70% of X-ray luminous cluster cores at z=0.2 are dynamically immature and strongly heterogeneous Ringberg, Hi-z clusters
Structural segregation [~40%] Possible Systematics? [~10-20%] M-T relation or M-T scatter plot? Smith et al., 2005 Finoguenov et al., 2001 • Unrelaxed clusters are 40% hotter than relaxed clusters (2.5σ) • Consistent with hydro simulations of cluster-cluster mergers (Ricker & Sarazin 2001, Randall et al. 2003) Ringberg, Hi-z clusters
Better agreement with weak lensing? Ringberg, Hi-z clusters
weak lensing shear profile Ringberg, Hi-z clusters
Lensing lensing weak lensing scatter plots… (~150 z/cluster) dynamics X-ray Ringberg, Hi-z clusters
Offset between dynamics and mass: sign of merger due to optical selection ? Or the fact that those systems are still young? A big scatter between Tx and Mass: we can probably do better (including strong lensing) but … limited by cluster substructure Need better data and statistics … ie. go from sample of 10s to sample of 100s Better agreement with weak lensing? Ringberg, Hi-z clusters
The MAssive Cluster Survey (MACS) • MACS is covering a very wide area and thus is able to discover the most x-ray luminous clusters unlike other surveys. • Most massive clusters should be strong lenses • ~120 z>0.3 MACS clusters to be observed with Chandra & ACS SNAP • 10 MACS cluster have been observed with HST/ACS Ringberg, Hi-z clusters
10 clusters at z~0.55 HST/ACS imaging F555W, F814W 5ksec/filter Keck/LRIS + VLT/FORS spectroscopy (arcs and cluster galaxies) Blue and Red spectroscopy SUBARU/Suprime imaging Weak lensing and galaxy population Dt~2Gyr 2Gyr 2Gyr X-ray Luminosity z=0 z=0.2 z=0.5 z~1 MACS clusters at 0.5<z<0.6 Ringberg, Hi-z clusters
MACS 1149 z=1.5 z=1.89 Ringberg, Hi-z clusters
MACS 0717 z=2.96 Ly- blob Ringberg, Hi-z clusters
MACS 0257 z=1.06 Ringberg, Hi-z clusters
MACS/HST weak lensing Ringberg, Hi-z clusters
Marshall et al 2006 Simulation data MACS/HST weak lensing Cluster mass reconstruction method using (NFW) blobs that can combine strong+weak lensing data: using MCMC techniques To cope with complex Shape seen at high-z Atomic Inference Classical 2D reconstruction Ringberg, Hi-z clusters
4Mpc filament in MACSJ0717.5+3745Ebeling et al (GO: 10420, cycle 14) X-ray+Gal density Lensing Subaru+Gal density+ ACS survey Ringberg, Hi-z clusters
4Mpc filament in MACSJ0717.5+3745Ebeling, Barrett, Donovan, 2004 Galaxies with Spectra Redshift distribution Ringberg, Hi-z clusters
7 3 9 1 Does cluster substructure evolve? • Current status of MACS strong lensing analysis • Candidate gravitational multiple images identified • [Ground-based spectroscopy of arcs <~50% complete] • Broad brush demographics:- z=0.2z=0.55 Strong lensing clusters 8/10 10/10 Unrelaxed clusters 4/10 9/10 Candidate unrelaxed clusters 3/10 0/10 Relaxed cool core clusters 2/10 1/10 Relaxed non cool core clusters 1/10 0/10 Ringberg, Hi-z clusters
MACS Snapshot ACSEbeling et al (GO: 10491, cycle 14) • List of 124 MACS clusters to be observed with HST/ACS in SNAP mode in F814W • Aim at finding effective lensing clusters and strongly distorted arcs (statistics and magnified sources) • 5 clusters already observed Ringberg, Hi-z clusters
MACS Snapshot ACSEbeling et al (GO: 10491) First Strong Lensing IDs Ringberg, Hi-z clusters
RXJ0152-29 a massive cluster at z~0.83 VIMOS/IFU Field of view X-ray luminous cluster at z=0.83 At least 8 multiple image systems, one at z=3.9 (Umetsu et al 2005)=> high ellipticity for DM, indicative of a merger. Ideal probe for VIMOS/IFU Potential interest for cosmology (Golse et al 2002)
Lensing for Cluster Physics • Lensing is probing mass relatively easily, measuring substructure gets more difficult at higher z, but is clearly seen! • Scattered relation between Mass and X-ray - depends on physical state and substructure (merger/relaxed) • Higher substructures at higher redshift (lots of lensing till z~0.8 in massive systems)? • Cosmology with cluster is likely to be hard - at least with current cluster sample size (10s) need much larger sample, but will learn some physics. Ringberg, Hi-z clusters