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The DEEP2 Redshift Survey. Marc Davis UC Berkeley. The DEEP2 Galaxy Redshift Survey used the DEIMOS spectrograph at the Keck II telescope to study both galaxy properties and large-scale structure at z~ 1. The DEEP2 Collaboration. Other Institutions J. Newman (LBNL) A. Coil (Arizona)
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The DEEP2 Redshift Survey Marc Davis UC Berkeley Granada, October 2007
The DEEP2 Galaxy Redshift Survey used the DEIMOS spectrograph at the Keck II telescope to study both galaxy properties and large-scale structure at z~1. The DEEP2 Collaboration Other Institutions J. Newman (LBNL) A. Coil (Arizona) C. Willmer (Arizona) B. Weiner (Arizona) R. Schiavon (UVA) C. Conroy (Princeton) N. Kaiser (Hawaii) D. Finkbeiner (Harvard) A. Connolly (Pitt.) U.C. Santa Cruz D. Phillips S. Kassin K. Noeske A. Metevier L. Lin N. Konidaris G. Graves J. Harker U.C. Berkeley M. Davis (PI) D. Croton M. Cooper B. Gerke R. Yan U.C. Santa Cruz S. Faber (Co-PI) D. Koo P. Guhathakurta
DEEP2 has been made possible by DEIMOS, a new instrument on Keck II • DEIMOS: • PI: Faber • wide-field multiplexing (up to 160 slitlets over a 16’x4’ field) • high resolution (R~5000) • spectral range (~2600 Å at highest resolution) • CCD array of 8k x 8k Granada, October 2007
Optics are key to the success of DEIMOS Complex design by Harlan Epps Brilliant work by Dave Hilyard
DEEP2 pre-selects high-z galaxies using observed colors Granada, October 2007
DEEP2 mask selection Targeted galaxies are enclosed with white curves Solid slits are objects selected on a given mask. dotted and dashed lines are galaxies from neighboring masks.
DEEP2 slitmask spectroscopy l position Using custom-milled slitmasks with DEIMOS we obtained spectra of ~150 targets at a time. A total of 400 slitmasks was required for the survey; we tilted slits up to 30 degrees to obtain rotation curves. Granada, October 2007
DEEP2/CFHT B,R,I GALEX NUV+FUV Chandra & XMM: XMM Chandra (1.6Ms) AEGIS:the All-wavelength Extended Groth Strip International Survey Spitzer MIPS, IRAC DEEP2 spectra and Caltech/JPL Ks imaging HST/ACS V,I (Cycle 13) Plus VLA (6 & 21 cm), SCUBA, etc…. Granada, October 2007
X-ray analysis - detection and photometry • P.Nandra et al. • Each square has integration time of 200 ksec • Source selection and photometry by own method • Elliptical shaped PSFs • All data will be released in August, 2007 1.6 Ms Granada, October 2007
A Redshift Survey at z=1: • 3 sq. degrees • 4 fields (0.5o x <2o) • 80 Keck nights, one-hour exposures to RAB=24.1 • primarily z~0.75-1.4 (pre-selected using BRI photometry) • 47,000 unique redshifts, error ~30 km/s • ~5·106 h-3Mpc3 • 1200 l/mm: ~6500-9200 Å • 1.0” slit: FWHM 68 km/s • z=0.7-1.4 spans lookback time ~6.0 - 8.0 Gyr ago • Within DEEP2 we are surveying 2.5 Gyr or ~20% of the history of the Universe, and SDSS/2dF comparisons give ~3x this baseline Granada, October 2007
Redshift Distribution of DEEP2 Survey Granada, October 2007
DEEP2 Status Update • DEEP2 began observations in July 2002. • Observations are now >99% finished, with >49k spectra in hand and 3 of 4 fields completed. • Follow-up observations have begun. • ALL the data is already public: • http://deep.berkeley.edu/DR4 • The catalog and 2d spectra is all available, and others are releasing Chandra, Spitzer, GALEX, HST, …. Granada, October 2007
τCDM ΛCDM Ω=0.3, ΩΛ =0.7 Ω=1 o 1015 Mo *10 14.5-15Mo . 1014-14.5 Mo Cluster abundance depends on cosmology Evrard et al. 02 Hubble volume simulations Granada, October 2007 Brian F. Gerke
DEEP2: Gerke et al 2005 2PIGG:Eke et al 2004 z=1.0 z=0.75 Granada, October 2007
Redshift Maps in 4 Fields: z=0.7-1.3 Cone diagram of 1/12 of the full DEEP2 sample Granada, October 2007
position l, z Galaxy groups in DEEP2 • Overdensities identified in redshift space. • Use the VDM algorithm of Marinoni et al. (2002). • Group in early DEEP2 data s~250 km/sec Granada, October 2007
DEEP2 Group Catalog Groups with >350 km/s Shown are groups for 3 fields --length of ellipse proportional to velocity dispersion Granada, October 2007 Gerke et al. 2005,astro-ph/0410721
Apparent abundance of groups: dN(s,z)/dzds • Provides a useful test of dark energy eq. of state (Newman et al, 2002) • differences in the volume element varies by 3x between w=0 and w=-1 • For groups of modest-mass, the evolution of dispersion is 2nd order Why search for groups in DEEP2? • Heavy black curve is T=.3DEIMOS took ~7 years to build; at time of designing science expt. T was still undetermined, and DE was not discussed.
Projected constraints Computed with DM halos in simulated DEEP2 and 2dF light cones, constructed from the Millennium Run. In each panel, the suppressed parameter is held fixed. input cosmology Granada, October 2007 Brian F. Gerke
DEEP2 Cluster Counts DEEP2 survey counted ~300 groups Velocity dispersion measured in each case Counts of N(, z) is a strong test of w Have not got mock catalogs with the evolving color selection, making it difficult to proceed B. Gerke will have results out “soon”
Measuring Kaiser infall in (rp,) Coil et al, 2008 • The blue galaxies show fully developed coherent infall pattern on scales >5 Mpc, as expected. • The red galaxies have very extended fingers of god, as expected.
Kaiser infall, MOCKS Coil et al, 2008 Millenium mocks, not a bad approximation
By combining area with depth, AEGIS allows us to study rare objects in detail… B. Gerke, JN et al. 2006, AEGIS ApJL, Accepted Granada, October 2007
Like a spectroscopically identified, dual AGN at z=0.7 Hb [OIII] 4959 [OIII] 5007 position l/ z Granada, October 2007
HST reveals a fairly-normal early-type host Granada, October 2007
Rotation Curves of 88 galaxies with HST and DEIMOS’s Spatial Resolution Study evolution of Spirals Metevier et al, 2007, in process
Ly-alpha emission seen in many slits Slits are 1” long, more than 50% blank field, giving > 1 sq arcminute for deep search, 3 < z < 6 Searching by “eye” for asymmetric emission lines So far they have searched ~20% of fields and found 9 clean systems Sawicki et al, in preparation
Conclusions on DEEP2 • DEEP2 observations are >99% done • Work not yet published is study of galaxy clustering • DR4 has occurred this August:http://deep.berkeley.edu/DR4 • AEGIS ApJL special issue • Way too many new results to cover in one talk! • A Spectroscopic survey has many followups! Granada, October 2007