Cosmology with SNAP G. Aldering, C. Bebek, W. Carithers, S. Deustua, W. Edwards, J. Frogel, D. Groom, S. Holland, D. Huterer*, D. Kasen, R. Knop, R. Lafever, M. Levi, E. Linder, S. Loken, P. Nugent, S. Perlmutter, K. Robinson (Lawrence Berkeley National Laboratory) E. Commins, D. Curtis, G. Goldhaber, J. R. Graham, S. Harris, P. Harvey, H. Heetderks, A. Kim, M. Lampton, R. Lin, D. Pankow, C. Pennypacker, A. Spadafora, G. F. Smoot (UC Berkeley) C. Akerlof, D. Amidei, G. Bernstein, M. Campbell, D. Levin, T. McKay, S. McKee, M. Schubnell, G. Tarle, A. Tomasch (U. Michigan) P. Astier, J.F. Genat, D. Hardin, J.- M. Levy, R. Pain, K. Schamahneche (IN2P3) A. Baden, J. Goodman, G. Sullivan (U.Maryland) R. Ellis, A. Refregier* (CalTech) A. Fruchter (STScI) L. Bergstrom, A. Goobar (U. Stockholm) C. Lidman (ESO) J. Rich (CEA/DAPNIA) A. Mourao (Inst. Superior Tecnico,Lisbon) Eric Linder Berkeley Lab

Probing Dark Energy Models

Supernova Requirements

From Science Goals to Project Design Science Measure  M and  Measure w and w (z) Data Set Requirements Discoveries 3.8 mag before max Spectroscopy with S/N=10 at 15 Å bins Near-IR spectroscopy to 1.7  m Statistical Requirements Sufficient (~2000) numbers of SNe Ia …distributed in redshift …out to z < 1.7 Systematics Requirements Identified and proposed systematics: Measurements to eliminate / bound each one to +/–0.02 mag Satellite / Instrumentation Requirements ~2-meter mirrorDerived requirements: 1-square degree imager High Earth orbit Spectrograph ~50 Mb/sec bandwidth (0.35  m to 1.7  m)

SNAP a simple dedicated experiment to study the dark energy —Dedicated instrument, essentially no moving parts —Mirror: 2 meter aperture sensitive to light from distant SN —Photometry: with 1°x 1° billion pixel mosaic camera, high-resistivity, rad- tolerant p-type CCDs and, HgCdTe arrays. (  m) —Integral field optical and IR spectroscopy:  m, 2”x2” FOV Mission Design

GigaCAM, a one billion pixel array l Approximately 1 billion pixels l ~140 Large format CCD detectors required, ~30 HgCdTe Detectors l Larger than SDSS camera, smaller than H.E.P. Vertex Detector (1 m 2 ) l Approx. 5 times size of FAME (MiDEX)GigaCAM

Focal Plane Layout with Fixed Filters

Q1 Q2 Q3 Q4 Step and Stare and Rotation

High-Resistivity CCD’s New kind of CCD developed at LBNL Better overall response than more costly “thinned” devices in use High-purity silicon has better radiation tolerance for space applications The CCD’s can be abutted on all four sides enabling very large mosaic arrays Measured Quantum Efficiency at Lick Observatory (R. Stover):

LBNL CCD’s at NOAO See September 2001 newsletter at 1)Near-earth asteroids 2)Seyfert galaxy black holes 3)LBNL Supernova cosmology Cover picture taken at WIYN 3.5m with LBNL 2048 x 2048 CCD (Dumbbell Nebula, NGC 6853) Science studies to date at NOAO using LBNL CCD’s: Blue is H-alpha Green is SIII 9532Å Red is HeII 10124Å.

Slit Plane Detector Camera Prism Collimator Integral Field Unit Spectrograph Design SNAP Design:

Lightcurves and Spectra from SNAP Goddard/Integrated Mission Design Center study in June 2001: no mission tallpoles Goddard/Instrument Synthesis and Analysis Lab. study in Nov. 2001: no technology tallpoles

Science Reach Key Cosmological Studies Type II supernova Weak lensing Strong lensing Galaxy clustering Structure evolution Star formation/reionization

A Resource for the Science Community SNAP main survey will be 4000x larger (and as deep) than the biggest HST deep survey, the ACS survey Complementary to NGST: target selection for rare objects Can survey 1000 sq. deg. in a year to I=29 or J=28 (AB mag) Archive data distributed Guest Survey Program Whole sky can be observed every few months Galaxy populations and morphology to coadded m=31 Quasars to redshift 10 Epoch of reionization through Gunn-Peterson effect Lensing projects: Mass selected cluster catalogs Evolution of galaxy-mass correlation function Maps of mass in filaments