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The Accelerating Universe

The Accelerating Universe. Probing Dark Energy with Supernovae. Eric Linder Berkeley Lab. Evidence for Acceleration. Supernovae Ia:  DE , w=p/ , w´=dw/dz Observation -- Magnitude-redshift relation. Age of universe:

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The Accelerating Universe

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  1. The Accelerating Universe Probing Dark Energy with Supernovae Eric Linder Berkeley Lab

  2. Evidence for Acceleration Supernovae Ia: DE, w=p/ , w´=dw/dz Observation -- Magnitude-redshift relation Age of universe: Contours of t0 parallel CMB acoustic peak angle: t0=14.0±0.5 Gyr [Flat universe, adiabatic perturbations] CMB Acoustic Peaks: Substantial dark energy, e.g. 0.49 < < 0.74 [Small GW contribution, LSS, H0] Large Scale Structure: Power spectrum Pk, Growth rate, “looks” [simulations]

  3. Supernova Cosmology

  4. A Dark Energy Universe Tyson

  5. Correlation of Age with CMB Peak Angle DASI data only Knox et al.

  6. CMB Power Spectrum and  Tegmark

  7. CMB Power Spectrum

  8. Matter Power Spectrum

  9. CMB + 2dF (no SN) Efstathiou et al.

  10. MAP Sky Coverage Wright Jan ‘02 Nov ‘01 Wright Apr ‘02 Oct ‘02

  11. Dark Energy • Supernova data shows an acceleration of the expansion, implying that the universe is dominated by a new Dark Energy! • Remarkable agreement between Supernovae & recent CMB results. Credit STScI

  12. Dark Energy Theory 1970s – Why M ~ k? 1980s – Inflation! Not curvature. 1990s – Why M ~ ? 2000s – Quintessence! Not ? Cosmological constant is an ugly duckling Dynamic scalar field is a beautiful swan Lensing  =0.7+0.1-0.2Chiba & Yoshii Supernovae  =0.72+0.08-0.09 SCP, HiZ Ly Forest  =0.66+0.09-0.13 D. Weinberg et al.

  13. : Ugly Duckling Field Theorist: Vacuum – Lorentz invariant Tab~ab = diag { -1, 1, 1, 1} p = - Naturally, Evac~ 1019 GeV E~ meV =0? Astrophysicist: Einstein equations – gab  p = - Naturally,  =const= PL = 10120 Today M • Fine Tuning Puzzle – why so small? • Coincidence Puzzle – why now?

  14. Scalar Field: Beautiful Swan Astrophysicist: Friedmann equations – (å/a)2=(8/3)(m+) ä/a=-(4/3)(m++3p) Field Theorist: Lagrangian – L=(1/2)aa-V()(1/2)2-V Tab= ab - L gab . =K+V p=K-V w=p/ = (K+V) / (K-V)  [-1, +1] Slow Roll (Inflation) K << V  p=- w=-1 Free Field (kination) V << K  p=+ w=+1 Coherent Oscillations (Axions) <V>=<K>  p=0  w=0 (matter)

  15. Fundamental Physics  (a)=  (0)e-3dlna(1+w) ~ a-3(1+w) w(z)=w0+w’z Astrophysics  Cosmology  Field Theory r(z)  Equation of state w(z)  V() V ( (a(t)) ) SN CMB etc. “Would be number one on my list of things to figure out” - Edward Witten “Right now, not only for cosmology but for elementary particle theory this is the bone in our throat” - Steven Weinberg What is the dark energy? Is =0 ?

  16. Type Ia Supernovae • Characterized by no Hydrogen, but with Silicon • Progenitor C/O White Dwarf accreting from companion • Just before Chandrasekhar mass, thermonuclear runaway • Standard explosion from nuclear physics

  17. 1 Parameter Family Homogeneity

  18. Hubble diagram – low z

  19. Hubble diagram - SCP 0.2 0.5 1 0.6 1.0 0.2 0.4 0.8 redshift z In flat universe: M=0.28 [.085 stat][.05 syst] Prob. of fit to =0 universe: 1%

  20. Supernova Cosmology

  21. Supernovae Probes - Generations Proposed Near Term Current (offset) Original

  22. SNAP: The Third Generation

  23. Dark Energy Equation of State

  24. Hubble Diagram

  25. Dark Energy Exploration with SNAP Current ground based compared with Binned simulated data and a sample of Dark energy models

  26. Probing Dark Energy Models

  27. From Science Goalsto Project Design Science • Measure M and  • Measure w and w (z) Systematics Requirements Statistical Requirements • Identified and proposed systematics: • Measurements to eliminate / bound each one to +/–0.02 mag • Sufficient (~2000) numbers of SNe Ia • …distributed in redshift • …out to z < 1.7 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 • • • Satellite / Instrumentation Requirements • ~2-meter mirror Derived requirements: • 1-square degree imager • High Earth orbit • Spectrograph • ~50 Mb/sec bandwidth (0.35 m to 1.7 m) • • •

  28. Mission Design

  29. SNAP Survey Fields

  30. GigaCAM GigaCAM, a one billion pixel array • Approximately 1 billion pixels • ~140 Large format CCD detectors required, ~30 HgCdTe Detectors • Larger than SDSS camera, smaller than H.E.P. Vertex Detector (1 m2) • Approx. 5 times size of FAME (MiDEX)

  31. Focal Plane Layout with Fixed Filters

  32. Step and Stare and Rotation Q1 Q2 Q4 Q3

  33. 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):

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

  35. Science Goals – F21

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

  37. What makes the SN measurement special?Control of systematic uncertainties At every moment in the explosion event, each individual supernova is “sending” us a rich stream of information about its internal physical state. Lightcurve & Peak Brightness Images M and L Dark Energy Properties Redshift & SN Properties Spectra data analysis physics

  38. Time Series of Spectra = SN “CAT Scan”

  39. 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

  40. Supernova Requirements

  41. Advantages of Space

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

  43. SNAP: The Third Generation

  44. Dark Energy Equation of State

  45. Precision Cosmology NOW SNAP Tegmark

  46. Primary Science Mission Includes… Weak lensing galaxy shear observed from space vs. ground Bacon, Ellis, Refregier 2000

  47. …And Beyond 10 band ultradeep imaging survey Feed NGST, CELT (as Palomar 48” to 200”, SDSS to 8-10m) Quasars to z=10 GRB afterglows to z=15 Galaxy populations and morphology to coadd m=32 Galaxy evolution studies, merger rate Stellar populations, distributions, evolution Epoch of reionization thru Gunn-Peterson effect Low surface brightness galaxies in H’ band, luminosity function Ultraluminous infrared galaxies Kuiper belt objects Proper motion, transient, rare objects

  48. SNAP Collaboration 12 institutions, ~50 researchers 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)

  49. SNAP at the American Astronomical Society Jan. 2002 Meeting Oral Session 111. Science with Wide Field Imaging in Space: The Astronomical Potential of Wide-field Imaging from Space S. Beckwith (Space Telescope Science Institute) Galaxy Evolution: HST ACS Surveys and Beyond to SNAP G. Illingworth (UCO/Lick, University of California) Studying Active Galactic Nuclei with SNAP P.S. Osmer (OSU), P.B. Hall (Princeton/Catolica) Distant Galaxies with Wide-Field Imagers K. M. Lanzetta (State University of NY at Stony Brook) Angular Clustering and the Role of Photometric Redshifts A. Conti, A. Connolly (University of Pittsburgh) SNAP and Galactic Structure I. N. Reid (STScI) Star Formation and Starburst Galaxies in the Infrared D. Calzetti (STScI) Wide Field Imagers in Space and the Cluster Forbidden Zone M. E. Donahue (STScI) An Outer Solar System Survey Using SNAP H.F. Levison, J.W. Parker (SwRI), B.G. Marsden (CfA) Oral Session 116. Cosmology with SNAP: Dark Energy or Worse S. Carroll (University of Chicago) The Primary Science Mission of SNAP S. Perlmutter (Lawrence Berkeley National Laboratory) SNAP: mission design and core survey T. A. McKay (University of Michigan Sensitivities for Future Space- and Ground-based Surveys G. M. Bernstein (Univ. of Michigan) Constraining the Properties of Dark Energy using SNAP D. Huterer (Case Western Reserve University) Type Ia Supernovae as Distance Indicators for Cosmology D. Branch (U. of Oklahoma) Weak Gravitational Lensing with SNAP A. Refregier (IoA, Cambridge), Richard Ellis (Caltech) Strong Gravitational Lensing with SNAP R. D. Blandford, L. V. E. Koopmans, (Caltech) Strong lensing of supernovae D.E. Holz (ITP, UCSB) Poster Session 64. Overview of The Supernova/Acceleration Probe: Supernova / Acceleration Probe: An Overview M. Levi (LBNL) The SNAP Telescope M. Lampton (UCB) SNAP: An Integral Field Spectrograph for SN Identification R. Malina (LAMarseille,INSU), A. Ealet (CPPM) SNAP: GigaCAM - A Billion Pixel Imager C. Bebek (LBNL) SNAP: Cosmology with Type Ia Supernovae A. Kim (LBNL) SNAP: Science with Wide Deep Fields E. Linder (LBNL)

  50. 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

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