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CLASH: C luster L ensing A nd S upernova survey with H ubble. M. Postman, P.I., with 34 co-investigators (18 institutions, 10 countries) . WFC3 Parallels. Cluster Pointings. ACS Parallels. 6 arcmin. = 2.2 Mpc @ z=0.5. SN search cadence: 10d-20d , 4 epochs per orient.
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CLASH:Cluster Lensing And Supernova survey with Hubble M. Postman, P.I., with 34 co-investigators (18 institutions, 10 countries) WFC3 Parallels Cluster Pointings ACS Parallels 6 arcmin. = 2.2 Mpc @ z=0.5 SN search cadence: 10d-20d, 4 epochs per orient Footprints of HST Cameras: ACS FOV in yellow, WFC3/IR FOV in red, WFC3/UVIS in blue. Lensing amplification small at these radii 524 orbits, 25 clusters, 16 filters, ~3 years
Abell 209 Abell 383 core Abell 611 Abell 963 Abell 2261 CLJ1226+3332 MACS 0329-0211 MACS 0717+3745 MACS 0744+3927 MACS 1115+0129 MACS 1149+2223 MACS 1206-0847 MS-2137 core RXJ 0647+7015 RXJ 1347-1145 RXJ 1423+2404 RXJ 1720+3536 RXJ 2129+0005 All clusters have Tx > 5 keV z_med ~ 0.4 MACS 0429-0253 RXJ 1532+3020 MACS 1931-2634 RXJ 2248-4431 MACS 1311-0310 Cutouts of x-ray images of 23 of the 25 CLASH clusters from Chandra Observatory
CLASH: 16 Passbands per cluster from UV to NIR Why 16 filters? Spectroscopic redshifts Photometric redshifts • F225W … 235.9 nm WFC3/UVIS • F275W … 270.4 nm WFC3/UVIS • F336W … 335.5 nm WFC3/UVIS • F390W … 392.1 nm WFC3/UVIS • F435W … 430.6 nm ACS/WFC • F475W … 474.2 nm ACS/WFC • F606W … 592.0 nm ACS/WFC • F625W … 629.8 nm ACS/WFC • F775W … 769.4 nm ACS/WFC • F814W … 806.9 nm ACS/WFC • F850LP … 906.0 nm ACS/WFC • F105W … 1.055 μm WFC3/IR • F110W … 1.152 μm WFC3/IR • F125W … 1.248 μm WFC3/IR • F140W … 1.392 μm WFC3/IR • F160W … 1.536 μm WFC3/IR Mag distn of multiply lensed arcs in A1689 and CL0024 Arcs in A1689 and CL0024 Will yield photometric redshifts with rms error of ~2% x(1 + z) for sources down to ~26 AB mag.
What is the characteristic distribution of DM in a typical cluster, and what implications does this distribution have for structure formation and the nature of DM? ΛCDM Theory ΛCDM Theory Umetsu et al. 2010 LCDM prediction from Duffy et al. 2008 • CLASH will: • Use 3 independent lensing constraints: SL, WL, mag bias • Have a well-selected cluster sample with minimal lensing bias • Definitively derive the representative equilibrium mass profile shape • Robustly measure cluster DM concentrations and their dispersion as a function of cluster mass (and possibly their redshift evolution). • Provide excellent calibration of mass-observable relations for clusters
What degree of substructure exists in the DM distribution in cluster cores? Abell 1689 Coe et al. 2010 HST Image of Cluster Reconstructed Mass Surface Density Region of Reliable Reconstruction DM substructure resolution in this map is ~23 kpc. DM substructure resolution for typical CLASH cluster will be ~30 – 40 kpc.
Abell 383 SN Candidate “Caligula” Abell 383 SN Candidate “Nero” Does the Equation of State of Dark Energy Depend on Time? Reference Discovery Difference Nov 18, 2010 Dec 8, 2010 Dec 28, 2010 ACS, F850LP, z ~ 0.3 WFC3-IR, F160W, z ~ 0.7 or 1.7 Expect CLASH to find 10 – 20 SNe at z>1; and ~6 with z > 1.5, doubling the known number of z > 1 SNe. Two MCT HST programs (CLASH and CANDELS) will detect SNe Ia at 1.0 < z < 2.5. CLASH and CANDELS provide a direct test of the SN systematics in a matter-dominated universe. Δ mag (vs. wo = -1, wa = 0) MCT MCT CURRENT HST LIFETIME
What are the characteristics of the most distant galaxies in the universe? Bradley et al. 2010 (in prep): Abell 1703 – Brightest z ~ 7 candidate known (H160 ~ 24.3 AB), μ ~ 3 - 5 Zitrin et al. 2010 • Reconstruction of a z = 4.92 source lensed by the z = 0.33 cluster MS1358+62. • Best resolved high-z object: spatial resolution of ~50 pc (rest-frame UV) • Equivalent to 20-m space telescope resolution of a non-lensed z=5 galaxy! z = 4.92 Galaxy ACS PSF How object would look without cluster lensing Lensing greatly enhances the ability to detect distant galaxies and provides an additional constraint on their redshifts, as the projected position of the lensed object is a function of the source redshift. 0.2”
Concluding Comments • CLASH observations with HST began in November. The 25 clusters will be observed over the course of cycles 18-20 (~3 years): 10, 10, 5. • Represents a major observational initiative to constrain the properties of DM, high-z galaxies, and advance our understanding of DE. • Immediate public access to all HST data. • High-level science products will be released on a regular schedule, including compilations of x-ray, IR, sub-mm, and spectroscopic data. • http://www.stsci.edu/~postman/CLASH
CLASH Yields a Significant Expansion of SL Cluster Data Strongly Lensing Clusters with 3 or more filters from HST (ACS and/or WFC3) Figure credit: Dan Coe CLASH doubles the number of SL clusters with >3 HST passbands. CLASH has uniform and well-defined sample selection criteria. Vast improvement in number of SLCswith >6 passbands – new territory for science.