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Fundamental Physics through Fundamental Physics through AstrophysicsAstrophysics

Fundamental Physics through Fundamental Physics through AstrophysicsAstrophysics

Christopher StubbsChristopher Stubbs

Department of Physics Department of Physics DepartmeDepartment nt of Astronomyof Astronomy

Harvard UniversityHarvard Universitycstubbs@fas.harvard.educstubbs@fas.harvard.edu

Christopher StubbsChristopher Stubbs

Department of Physics Department of Physics DepartmeDepartment nt of Astronomyof Astronomy

Harvard UniversityHarvard Universitycstubbs@fas.harvard.educstubbs@fas.harvard.edu

                                                 

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Astrophysical Evidence Astrophysical Evidence for New Physicsfor New Physics

Astrophysical Evidence Astrophysical Evidence for New Physicsfor New Physics

Matter-antimatter asymmetry • Baryon number & CP violation in early universe?

Non-baryonic Dark Matter • New particle physics sector?

Neutrino oscillations, mass constraints• Non-zero masses, mixing/oscillations

Accelerating expansion of the Universe• Evidence for weirdness in the vacuum• Puzzle #1: why is this effect so small?• Puzzle #2: why is this effect so large?

Matter-antimatter asymmetry • Baryon number & CP violation in early universe?

Non-baryonic Dark Matter • New particle physics sector?

Neutrino oscillations, mass constraints• Non-zero masses, mixing/oscillations

Accelerating expansion of the Universe• Evidence for weirdness in the vacuum• Puzzle #1: why is this effect so small?• Puzzle #2: why is this effect so large?

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Focus is shifting…Focus is shifting…Focus is shifting…Focus is shifting…10 years ago10 years ago

- What’s the Dark Matter?- What are the values of the cosmological

parameters (, q0, H0)? - What’s the connection between primordial

fluctuations and observed large scale structure?

10 years ago10 years ago- What’s the Dark Matter?- What are the values of the cosmological

parameters (, q0, H0)? - What’s the connection between primordial

fluctuations and observed large scale structure?

NowNow– What’s the Dark Matter?What’s the Dark Matter?– What physics is responsible for accelerated expansion?What physics is responsible for accelerated expansion?– What’s the connection between primordial fluctuations, What’s the connection between primordial fluctuations,

dark matter, and observed galactic structure?dark matter, and observed galactic structure?– How can we probe the foundations of gravity?How can we probe the foundations of gravity?

NowNow– What’s the Dark Matter?What’s the Dark Matter?– What physics is responsible for accelerated expansion?What physics is responsible for accelerated expansion?– What’s the connection between primordial fluctuations, What’s the connection between primordial fluctuations,

dark matter, and observed galactic structure?dark matter, and observed galactic structure?– How can we probe the foundations of gravity?How can we probe the foundations of gravity?

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A Cosmic Sum RuleA Cosmic Sum RuleA Cosmic Sum RuleA Cosmic Sum Rule

General Relativity + isotropy and homogeneity require General Relativity + isotropy and homogeneity require that (in the relevant units)that (in the relevant units)

geometrygeometry + + mattermatter + + = 1 = 1

If the underlying geometry is flat, and if If the underlying geometry is flat, and if mm <1 then the <1 then the

cosmological constant term cosmological constant term must must be non-zero. be non-zero.

So it would seem……..So it would seem……..

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Emergence of a Standard CosmologyEmergence of a Standard CosmologyEmergence of a Standard CosmologyEmergence of a Standard Cosmology

Our geometrically flat Universe started in a hot big bang Our geometrically flat Universe started in a hot big bang 13.7 Gyrs ago.13.7 Gyrs ago.

The evolution of the Universe is increasingly dominated by The evolution of the Universe is increasingly dominated by the phenomenology of the vacuum. the phenomenology of the vacuum.

Matter, mostly non-baryonic, Matter, mostly non-baryonic, is a minor component. is a minor component.

Luminous matter comprises Luminous matter comprises a preposterously low fraction a preposterously low fraction of the mass of the Universe. of the mass of the Universe.

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This picture is supported by multiple This picture is supported by multiple independent lines of evidenceindependent lines of evidence

This picture is supported by multiple This picture is supported by multiple independent lines of evidenceindependent lines of evidence

• Lower bound on age, from starsLower bound on age, from stars

• Inventories of cosmic matter contentInventories of cosmic matter content

• Measurements of expansion history using supernovaeMeasurements of expansion history using supernovae

• Primordial element abundances Primordial element abundances

• CMB provides strong confirmation…. WMAP CMB provides strong confirmation…. WMAP

• Lower bound on age, from starsLower bound on age, from stars

• Inventories of cosmic matter contentInventories of cosmic matter content

• Measurements of expansion history using supernovaeMeasurements of expansion history using supernovae

• Primordial element abundances Primordial element abundances

• CMB provides strong confirmation…. WMAP CMB provides strong confirmation…. WMAP

Dark Energy Constitutes A Dark Energy Constitutes A Crisis in Fundamental PhysicsCrisis in Fundamental Physics

Dark Energy Constitutes A Dark Energy Constitutes A Crisis in Fundamental PhysicsCrisis in Fundamental Physics

This crisis appears as profound as the one that This crisis appears as profound as the one that preceded the advent of quantum mechanics.preceded the advent of quantum mechanics.

Supported by multipleSupported by multiplelines of evidencelines of evidence….….CDMCDM

Or, are we collectively Or, are we collectively under the influence of the under the influence of the ““ether” of our time?ether” of our time?

Perhaps we can appealPerhaps we can appealto theory for some guidance…? to theory for some guidance…?

This crisis appears as profound as the one that This crisis appears as profound as the one that preceded the advent of quantum mechanics.preceded the advent of quantum mechanics.

Supported by multipleSupported by multiplelines of evidencelines of evidence….….CDMCDM

Or, are we collectively Or, are we collectively under the influence of the under the influence of the ““ether” of our time?ether” of our time?

Perhaps we can appealPerhaps we can appealto theory for some guidance…? to theory for some guidance…?

www.general-anesthesia.com

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. Well, that can’t be right…

0. Through some profound but not yet understood mechanism, the vacuum energy must be cancelled to arrive at value of identically zero ummm... Supersymmetry uhhh ...Planck Mass

0.7, you say?? String landscapes….uhhhh No, wait! IT’S ANTHROPIC!

Dark Energy TheoryDark Energy TheoryDark Energy TheoryDark Energy Theory

Parameterizing our Ignorance of Parameterizing our Ignorance of the Properties of Dark Energythe Properties of Dark Energy

Parameterizing our Ignorance of Parameterizing our Ignorance of the Properties of Dark Energythe Properties of Dark Energy

At least 4 alternatives:At least 4 alternatives:• Cosmological constant of Einstein• Departure from GR• Vacuum energy with some cutoff (QM)• Weird new field(s)

Use wUse wP/P/, equation of state parameter, , equation of state parameter, to try to discriminate: to try to discriminate:

ww1? 1?

w w w(z) = ww(z) = w00 + (1-a)w + (1-a)waa??

At least 4 alternatives:At least 4 alternatives:• Cosmological constant of Einstein• Departure from GR• Vacuum energy with some cutoff (QM)• Weird new field(s)

Use wUse wP/P/, equation of state parameter, , equation of state parameter, to try to discriminate: to try to discriminate:

ww1? 1?

w w w(z) = ww(z) = w00 + (1-a)w + (1-a)waa??

Probing the nature of Dark Energy Probing the nature of Dark Energy with Observationswith Observations

Probing the nature of Dark Energy Probing the nature of Dark Energy with Observationswith Observations

• SN Hubble diagramSN Hubble diagram

• Baryon oscillations Baryon oscillations

• Weak gravitational lensingWeak gravitational lensing

• Galaxy cluster abundances vs. redshiftGalaxy cluster abundances vs. redshift

See Dark Energy Task Force Report, Albrecht et al astro-ph/0609591, See Dark Energy Task Force Report, Albrecht et al astro-ph/0609591,

also Albrecht and Bernstein, astro-ph/0608269v2 also Albrecht and Bernstein, astro-ph/0608269v2

• SN Hubble diagramSN Hubble diagram

• Baryon oscillations Baryon oscillations

• Weak gravitational lensingWeak gravitational lensing

• Galaxy cluster abundances vs. redshiftGalaxy cluster abundances vs. redshift

See Dark Energy Task Force Report, Albrecht et al astro-ph/0609591, See Dark Energy Task Force Report, Albrecht et al astro-ph/0609591,

also Albrecht and Bernstein, astro-ph/0608269v2 also Albrecht and Bernstein, astro-ph/0608269v2

Surveys!Surveys!

Survey Figure of MeritSurvey Figure of MeritSurvey Figure of MeritSurvey Figure of Merit

Surveys exploit the 3 enabling technologies of Surveys exploit the 3 enabling technologies of contemporary optical astronomy:contemporary optical astronomy:

high efficiency detectorshigh efficiency detectors

large aperture opticslarge aperture optics

computation and data storagecomputation and data storage

Surveys exploit the 3 enabling technologies of Surveys exploit the 3 enabling technologies of contemporary optical astronomy:contemporary optical astronomy:

high efficiency detectorshigh efficiency detectors

large aperture opticslarge aperture optics

computation and data storagecomputation and data storage

FOM =N / t =φ

SNR⎡

⎣⎢

⎤

⎦⎥

Aε

φsky(δ)

Source flux, Source flux, signal to noise signal to noise

System: System: Collecting Area Collecting Area Field of View Field of View

Efficiency Efficiency

Site: sky brightness, Site: sky brightness, seeing seeing

Survey Figure of MeritSurvey Figure of MeritSurvey Figure of MeritSurvey Figure of Merit

Number of objects detected Number of objects detected per unit time, to given SNRper unit time, to given SNRNumber of objects detected Number of objects detected per unit time, to given SNRper unit time, to given SNR

bette

r

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The Current Generation: Measuring wThe Current Generation: Measuring w The Current Generation: Measuring wThe Current Generation: Measuring w • Wide field multiband, 2.5 m survey systemWide field multiband, 2.5 m survey system

• SDSS, SDSS 2

• Mosaic CCD imagers, 4 m, shared timeMosaic CCD imagers, 4 m, shared time• ESSENCE SN survey - CTIO 4m• CFHT Legacy Survey - CFHT 4m• Deep Lens Survey - 28 sq deg, CTIO 4m• Blanco Cosmology Survey - 100 sq deg• …

• Hubble Space Telescope, shared timeHubble Space Telescope, shared time• Cosmos - 2 degrees, HST• GOODS survey

• Wide field multiband, 2.5 m survey systemWide field multiband, 2.5 m survey system• SDSS, SDSS 2

• Mosaic CCD imagers, 4 m, shared timeMosaic CCD imagers, 4 m, shared time• ESSENCE SN survey - CTIO 4m• CFHT Legacy Survey - CFHT 4m• Deep Lens Survey - 28 sq deg, CTIO 4m• Blanco Cosmology Survey - 100 sq deg• …

• Hubble Space Telescope, shared timeHubble Space Telescope, shared time• Cosmos - 2 degrees, HST• GOODS survey

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Dark Energy’s Equation of StateDark Energy’s Equation of StateDark Energy’s Equation of StateDark Energy’s Equation of State w = 0, matter P = w w = 1/3 ,radiation

w = 1, w = N/3, topological defects

w = 0, matter P = w w = 1/3 ,radiation

w = 1, w = N/3, topological defects

3 3(1 )

0 0

(1 )( ) (1 )(1 ) (1 )

zw

L

c zD z z z dz

H+

+ ′ ′ ′= − + + +∫

For a flat Universe, luminosity For a flat Universe, luminosity distance depends only upon z, distance depends only upon z, , w., w.

(assumes w is constant) (assumes w is constant)

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(Hubble Space Telescope, NASA)(Hubble Space Telescope, NASA)

Supernovae are powerful cosmological probes

Distances to ~6% from brightness

Redshifts from features in spectra

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Redshift = Δλ/λ

DistancetoSupernova

Faraway

Nearby. . .

Δλλ

Schmidt et al, High-z SN TeamSchmidt et al, High-z SN Team

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The ESSENCE SurveyThe ESSENCE SurveyThe ESSENCE SurveyThe ESSENCE Survey• Our goal is to determine the equation of state Our goal is to determine the equation of state

parameter to 10%parameter to 10%

• This should help determine whether This should help determine whether belongs on belongs on the left or right side of the Einstein equations…the left or right side of the Einstein equations…

• w = w = 1 or dw/dz = 0 favors QM1 or dw/dz = 0 favors QM

• Supernovae are well suited to this task – they Supernovae are well suited to this task – they probe directly the epoch of probe directly the epoch of accelerating expansion. accelerating expansion.

• Our goal is to determine the equation of state Our goal is to determine the equation of state parameter to 10%parameter to 10%

• This should help determine whether This should help determine whether belongs on belongs on the left or right side of the Einstein equations…the left or right side of the Einstein equations…

• w = w = 1 or dw/dz = 0 favors QM1 or dw/dz = 0 favors QM

• Supernovae are well suited to this task – they Supernovae are well suited to this task – they probe directly the epoch of probe directly the epoch of accelerating expansion. accelerating expansion.

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Claudio Aguilera --- CTIO/NOAO Claudio Aguilera --- CTIO/NOAO

Brian Barris --- Univ of Hawaii Brian Barris --- Univ of Hawaii

Andy Becker --- Bell Labs/Univ. of Washington Andy Becker --- Bell Labs/Univ. of Washington

Peter Challis --- Harvard-Smithsonian CfA Peter Challis --- Harvard-Smithsonian CfA

Ryan Chornock --- UC Berkeley Ryan Chornock --- UC Berkeley

Alejandro Clocchiatti --- Univ Catolica de Chile Alejandro Clocchiatti --- Univ Catolica de Chile

Ricardo Covarrubias --- Univ of WashingtonRicardo Covarrubias --- Univ of Washington

Alex V. Filippenko --- Univ of Ca, Berkeley Alex V. Filippenko --- Univ of Ca, Berkeley

Arti Garg --- Harvard UniversityArti Garg --- Harvard University

Peter M. Garnavich --- Notre Dame University Peter M. Garnavich --- Notre Dame University

Malcolm Hicken --- Harvard University Malcolm Hicken --- Harvard University

Saurabh Jha --- UC BerkeleySaurabh Jha --- UC Berkeley

Robert Kirshner --- Harvard-Smithsonian CfA Robert Kirshner --- Harvard-Smithsonian CfA

Kevin Krisciunas --- Notre Dame Univ. Kevin Krisciunas --- Notre Dame Univ.

Bruno Leibundgut --- European Southern Observatory Bruno Leibundgut --- European Southern Observatory

Weidong D. Li --- Univ of California, Berkeley Weidong D. Li --- Univ of California, Berkeley

Thomas Matheson --- Harvard-Smithsonian CfAThomas Matheson --- Harvard-Smithsonian CfA

Gajus Miknaitis --- FermilabGajus Miknaitis --- Fermilab

Jose Prieto --- The Ohio State UniversityJose Prieto --- The Ohio State University

Armin Rest --- NOAO/CTIO Armin Rest --- NOAO/CTIO

Adam G. Riess --- Space Telescope Science Institute Adam G. Riess --- Space Telescope Science Institute

Brian P. Schmidt --- Mt. Stromlo Siding Springs Observatories Brian P. Schmidt --- Mt. Stromlo Siding Springs Observatories

Chris Smith --- CTIO/NOAO Chris Smith --- CTIO/NOAO

Jesper Sollerman --- Stockholm Observatory Jesper Sollerman --- Stockholm Observatory

Jason Spyromilio --- European Southern Observatory Jason Spyromilio --- European Southern Observatory

Christopher Stubbs --- Harvard UniversityChristopher Stubbs --- Harvard University

Nicholas B. Suntzeff --- CTIO/NOAO Nicholas B. Suntzeff --- CTIO/NOAO

John L. Tonry --- Univ of HawaiiJohn L. Tonry --- Univ of Hawaii

Michael Wood-Vasey --- Harvard UniversityMichael Wood-Vasey --- Harvard University

ESSENCE Survey TeamESSENCE Survey Team

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A 200-SN Hubble Diagram, with particular A 200-SN Hubble Diagram, with particular attention to systematicsattention to systematics

(ESSENCE team (ESSENCE team Monte Carlo, Monte Carlo, Garnavich et al, in Garnavich et al, in prep)prep)

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ImplementationImplementationImplementationImplementation• 6 year project on 4m telescope at 6 year project on 4m telescope at

CTIO in ChileCTIO in Chile

• Wide field images in 2 bands Wide field images in 2 bands

• Same-night detection of SNeSame-night detection of SNe

• Spectroscopy Spectroscopy Magellan, Keck, Gemini telescopes

• Near-IR from Hubble Near-IR from Hubble

• Goal is ~200 SNe, 0.2<z<0.8Goal is ~200 SNe, 0.2<z<0.8

• 6 year project on 4m telescope at 6 year project on 4m telescope at

CTIO in ChileCTIO in Chile

• Wide field images in 2 bands Wide field images in 2 bands

• Same-night detection of SNeSame-night detection of SNe

• Spectroscopy Spectroscopy Magellan, Keck, Gemini telescopes

• Near-IR from Hubble Near-IR from Hubble

• Goal is ~200 SNe, 0.2<z<0.8Goal is ~200 SNe, 0.2<z<0.8

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Equation of State DependenceEquation of State DependenceEquation of State DependenceEquation of State Dependence

Difference in apparent SN Difference in apparent SN brightness vs. z, brightness vs. z, =0.70, =0.70,

flat cosmologyflat cosmology Miknaitis et al, astro-ph/0701043 Miknaitis et al, astro-ph/0701043

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ESSENCE: 5 of 6 seasons ESSENCE: 5 of 6 seasons completed, 3 recent paperscompleted, 3 recent papersESSENCE: 5 of 6 seasons ESSENCE: 5 of 6 seasons completed, 3 recent paperscompleted, 3 recent papers

Miknaitis et alMiknaitis et al, , Survey design and optimization, Survey design and optimization, astro-ph/0701043astro-ph/0701043

Wood-Vasey et alWood-Vasey et al, Constraints on w, w’ , Constraints on w, w’ astro-ph/0701041astro-ph/0701041

Davis et alDavis et al, , Constraints on exotic theoriesConstraints on exotic theoriesastro-ph/0701510 astro-ph/0701510

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Wood-Vasey et al, astro-ph/0701041Wood-Vasey et al, astro-ph/0701041

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Joint SN & BAO Limits on wJoint SN & BAO Limits on wJoint SN & BAO Limits on wJoint SN & BAO Limits on w

• From Wood-Vasey et From Wood-Vasey et al, astro-ph/0701041al, astro-ph/0701041

• Combines ESSENCE Combines ESSENCE and SNLS and nearby and SNLS and nearby and HST supernovaeand HST supernovae

• BAO limits from BAO limits from Eisenstein et al Eisenstein et al

• Complementarity of Complementarity of techniquestechniques

• Different systematicsDifferent systematics

• From Wood-Vasey et From Wood-Vasey et al, astro-ph/0701041al, astro-ph/0701041

• Combines ESSENCE Combines ESSENCE and SNLS and nearby and SNLS and nearby and HST supernovaeand HST supernovae

• BAO limits from BAO limits from Eisenstein et al Eisenstein et al

• Complementarity of Complementarity of techniquestechniques

• Different systematicsDifferent systematics

(Assumes flat Universe)(Assumes flat Universe)

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Potential sources of systematic errorPotential sources of systematic errorPotential sources of systematic errorPotential sources of systematic error

• Flux calibrationsFlux calibrations

• Bias in distance determination codesBias in distance determination codes

• ExtinctionExtinction• Host galaxy• Our Galaxy• Atmosphere

• Passband errorsPassband errors• K corrections• Photometry normlization

• Nonlinearity in flux measurementsNonlinearity in flux measurements

• Flux calibrationsFlux calibrations

• Bias in distance determination codesBias in distance determination codes

• ExtinctionExtinction• Host galaxy• Our Galaxy• Atmosphere

• Passband errorsPassband errors• K corrections• Photometry normlization

• Nonlinearity in flux measurementsNonlinearity in flux measurements

Potential Systematics, Cont. Potential Systematics, Cont. Potential Systematics, Cont. Potential Systematics, Cont.

• Hubble bubble troubleHubble bubble trouble

• Gravitational lensingGravitational lensing

• Evolutionary effects in SneEvolutionary effects in Sne

• Biases or errors in low z sampleBiases or errors in low z sample

• Contamination by non Ia’s Contamination by non Ia’s

• Malmquist biasMalmquist bias

• Hubble bubble troubleHubble bubble trouble

• Gravitational lensingGravitational lensing

• Evolutionary effects in SneEvolutionary effects in Sne

• Biases or errors in low z sampleBiases or errors in low z sample

• Contamination by non Ia’s Contamination by non Ia’s

• Malmquist biasMalmquist bias

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Next-Generation FacilitiesNext-Generation FacilitiesNext-Generation FacilitiesNext-Generation Facilities

Microwave background - Microwave background - Better angular resolution CMB mapsBetter angular resolution CMB mapsDetection of clusters of galaxies vs. zDetection of clusters of galaxies vs. z

Supernovae – Supernovae – Dedicated Dark Energy satellite missionDedicated Dark Energy satellite missionLarge Synoptic Survey Telescope (LSST)Large Synoptic Survey Telescope (LSST)

Weak Gravitational LensingWeak Gravitational LensingBoth ground-based and space basedBoth ground-based and space based

Probing the foundations of gravityProbing the foundations of gravityEquivalence principleEquivalence principleInverse square lawInverse square law

SNAP, Lawrence Berkeley LaboratorySNAP, Lawrence Berkeley Laboratory

LSST CorporationLSST Corporation

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Imminent (~12 mo)Imminent (~12 mo) Imminent (~12 mo)Imminent (~12 mo) • PanSTARRS 1PanSTARRS 1

• 1.8 m aperture• 7 square degree field• 1.5 Gpix imager• Deep depletion detectors• Latitude +20

• SkymapperSkymapper• 1.35 m aperture• 5.7 sq degrees• Bands optimized for stellar astronomy• Latitude 30

• Galaxy cluster surveysGalaxy cluster surveys• South Pole Telescope• Atatcama Cosmology Telescope• Optical followup

– Spectroscopy– Imaging

• PanSTARRS 1PanSTARRS 1• 1.8 m aperture• 7 square degree field• 1.5 Gpix imager• Deep depletion detectors• Latitude +20

• SkymapperSkymapper• 1.35 m aperture• 5.7 sq degrees• Bands optimized for stellar astronomy• Latitude 30

• Galaxy cluster surveysGalaxy cluster surveys• South Pole Telescope• Atatcama Cosmology Telescope• Optical followup

– Spectroscopy– Imaging

PS 1 on HaleakalaPS 1 on Haleakala

PanSTARRS-1: a prototypePanSTARRS-1: a prototypePanSTARRS-1: a prototypePanSTARRS-1: a prototype1.8m telescope, 7 square degree FOV1.8m telescope, 7 square degree FOV

Telescope now in shakedownTelescope now in shakedown

1.4 Gpix camera slated for July 20071.4 Gpix camera slated for July 2007

Image processing pipeline, May 2007Image processing pipeline, May 2007

Operations to begin early 2008Operations to begin early 2008

1.8m telescope, 7 square degree FOV1.8m telescope, 7 square degree FOV

Telescope now in shakedownTelescope now in shakedown

1.4 Gpix camera slated for July 20071.4 Gpix camera slated for July 2007

Image processing pipeline, May 2007Image processing pipeline, May 2007

Operations to begin early 2008Operations to begin early 2008

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Pan-Starrs bandsPan-Starrs bandsPan-Starrs bandsPan-Starrs bands

g r i z y

4000 A break at z of 0.2 0.5 0.8 1.0 1.25 1.5

Detector-based system throughput Detector-based system throughput determinationdetermination

Detector-based system throughput Detector-based system throughput determinationdetermination

λ nm

QE

Spectrum of Vega NIST photodiode QE Spectrum of Vega NIST photodiode QE

Tunable laser (400 nm - 2 microns)Tunable laser (400 nm - 2 microns) Tunable laser (400 nm - 2 microns)Tunable laser (400 nm - 2 microns)

Second harmonic (532 Second harmonic (532 nm) generatornm) generator

Mixer (to 355 nm) Mixer (to 355 nm)

1.064 micron NdYAG 1.064 micron NdYAG pulsed pump laserpulsed pump laser

Tunable downconverterTunable downconverter

Second harmonic (532 Second harmonic (532 nm) generatornm) generator

Mixer (to 355 nm) Mixer (to 355 nm)

1.064 micron NdYAG 1.064 micron NdYAG pulsed pump laserpulsed pump laser

Tunable downconverterTunable downconverter

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Atmospheric Transmission Visible to NIRAtmospheric Transmission Visible to NIR(from SNAP team website)(from SNAP team website)

Atmospheric Transmission Visible to NIRAtmospheric Transmission Visible to NIR(from SNAP team website)(from SNAP team website)

Atmospheric TransmissionAtmospheric TransmissionAtmospheric TransmissionAtmospheric Transmission

Simultaneous Simultaneous multiband multiband imagerimager

Simultaneous Simultaneous multiband multiband imagerimager

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

Differential Differential spectroscopy spectroscopy (CTIO 1.5m)(CTIO 1.5m)

Differential Differential spectroscopy spectroscopy (CTIO 1.5m)(CTIO 1.5m)

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• Dark Energy SurveyDark Energy Survey• Equip CTIO 4m with 3 sq deg camera• 1/3 of the time, 5 year survey• Cluster photo-z’s, SNe, Weak Lensing, LSS

• Spectroscopic BAO surveysSpectroscopic BAO surveys• WFMOS, SDSS follow-on…• Photo-z’s not accurate enough for BAO?

• PanSTARRS 4PanSTARRS 4• Four 1.8m telescopes, PS-1 is prototype

• Large Synoptic Survey TelescopeLarge Synoptic Survey Telescope• 8.4m aperture• 9.6 sq degree field

• Dark Energy SurveyDark Energy Survey• Equip CTIO 4m with 3 sq deg camera• 1/3 of the time, 5 year survey• Cluster photo-z’s, SNe, Weak Lensing, LSS

• Spectroscopic BAO surveysSpectroscopic BAO surveys• WFMOS, SDSS follow-on…• Photo-z’s not accurate enough for BAO?

• PanSTARRS 4PanSTARRS 4• Four 1.8m telescopes, PS-1 is prototype

• Large Synoptic Survey TelescopeLarge Synoptic Survey Telescope• 8.4m aperture• 9.6 sq degree field

In the Planning/Design phaseIn the Planning/Design phaseIn the Planning/Design phaseIn the Planning/Design phase

New Camera for CTIO 4 New Camera for CTIO 4 meter telescope, plus meter telescope, plus

analysis pipeline analysis pipeline

Telescope and primary Telescope and primary mirror existmirror exist

Camera design and Camera design and development under way: development under way:

LBNL deep depletion CCDsLBNL deep depletion CCDs

Software under development Software under development BCS is precursorBCS is precursor

Not yet fully funded, to my Not yet fully funded, to my knowledge… 2010?knowledge… 2010?

New Camera for CTIO 4 New Camera for CTIO 4 meter telescope, plus meter telescope, plus

analysis pipeline analysis pipeline

Telescope and primary Telescope and primary mirror existmirror exist

Camera design and Camera design and development under way: development under way:

LBNL deep depletion CCDsLBNL deep depletion CCDs

Software under development Software under development BCS is precursorBCS is precursor

Not yet fully funded, to my Not yet fully funded, to my knowledge… 2010?knowledge… 2010?

Dark Energy Dark Energy SurveySurvey

Dark Energy Dark Energy SurveySurvey

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PanSTARRS 4PanSTARRS 4PanSTARRS 4PanSTARRS 4

• Basic notion is that Basic notion is that multiple apertures are multiple apertures are cheaper, for a given cheaper, for a given AA

• PS - 1 is a prototype, PS - 1 is a prototype, and software testbedand software testbed

• Plan is to place PS-4 Plan is to place PS-4 on Mauna Keaon Mauna Kea

• Partially fundedPartially funded

• Basic notion is that Basic notion is that multiple apertures are multiple apertures are cheaper, for a given cheaper, for a given AA

• PS - 1 is a prototype, PS - 1 is a prototype, and software testbedand software testbed

• Plan is to place PS-4 Plan is to place PS-4 on Mauna Keaon Mauna Kea

• Partially fundedPartially funded

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Large Synoptic Survey TelescopeLarge Synoptic Survey TelescopeLarge Synoptic Survey TelescopeLarge Synoptic Survey TelescopeHighly ranked in Decadal SurveyHighly ranked in Decadal Survey

Optimized for time domainOptimized for time domain

scan modescan mode

deep modedeep mode

10 square degree field10 square degree field

6.5m effective aperture6.5m effective aperture

24th mag in 20 sec24th mag in 20 sec

>20 Tbyte/night>20 Tbyte/night

Real-time analysisReal-time analysis

Simultaneous multiple science goalsSimultaneous multiple science goals

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LSST Merges 3 Enabling LSST Merges 3 Enabling Technologies Technologies

LSST Merges 3 Enabling LSST Merges 3 Enabling Technologies Technologies

• Large Aperture OpticsLarge Aperture Optics

• Computing and Data Storage Computing and Data Storage

• High Efficiency DetectorsHigh Efficiency Detectors

• Large Aperture OpticsLarge Aperture Optics

• Computing and Data Storage Computing and Data Storage

• High Efficiency DetectorsHigh Efficiency Detectors

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Large Mirror FabricationLarge Mirror FabricationLarge Mirror FabricationLarge Mirror Fabrication

University of ArizonaUniversity of Arizona

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Cost per GigabyteCost per GigabyteCost per GigabyteCost per Gigabyte

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Large Format CCD MosaicsLarge Format CCD MosaicsLarge Format CCD MosaicsLarge Format CCD MosaicsMegacam, CfA/HarvardMegacam, CfA/Harvard

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So Why Should So Why Should Physicists Physicists Care About the Large Care About the Large

Synoptic Survey Synoptic Survey Telescope?Telescope?

So Why Should So Why Should Physicists Physicists Care About the Large Care About the Large

Synoptic Survey Synoptic Survey Telescope?Telescope?

Fundamental Physics via AstrophysicsFundamental Physics via Astrophysics• Nature of Dark Matter (strong, weak and Nature of Dark Matter (strong, weak and lensing)lensing)• Dark Energy (SNe, lensing, Large Scale Structure)Dark Energy (SNe, lensing, Large Scale Structure)• Extreme Systems (linkages with LISA, EXIST…)Extreme Systems (linkages with LISA, EXIST…)

Qualitative leap in capabilities: AQualitative leap in capabilities: Aproduct an order of product an order of magnitude better than today. magnitude better than today.

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Some ExamplesSome ExamplesSome ExamplesSome Examples• Thousands of type Ia supernovaeThousands of type Ia supernovae

Detailed study of physics Isotropy of Hubble diagram Subdivide data set

• Host galaxy type• Redshift shells• SN color/decline parameter

• Time delays from strongly lensed Sne Time delays from strongly lensed Sne Constrains nature of dark matter

• Weak Lensing of galaxies as a probe of nature of dark Weak Lensing of galaxies as a probe of nature of dark energyenergy

• Optical counterparts to gravity wave sourcesOptical counterparts to gravity wave sources Break degeneracy in (1+z)Mchirp

• Thousands of type Ia supernovaeThousands of type Ia supernovae Detailed study of physics Isotropy of Hubble diagram Subdivide data set

• Host galaxy type• Redshift shells• SN color/decline parameter

• Time delays from strongly lensed Sne Time delays from strongly lensed Sne Constrains nature of dark matter

• Weak Lensing of galaxies as a probe of nature of dark Weak Lensing of galaxies as a probe of nature of dark energyenergy

• Optical counterparts to gravity wave sourcesOptical counterparts to gravity wave sources Break degeneracy in (1+z)Mchirp

More LSST OpportunitiesMore LSST OpportunitiesMore LSST OpportunitiesMore LSST Opportunities

• Neutrino masses probed toNeutrino masses probed to

(Wang et al PRL 94, 011302, 2005)(Wang et al PRL 94, 011302, 2005)

• Photometric redshift catalog to 26th magnitudePhotometric redshift catalog to 26th magnitude: : • Baryon oscillations• Catalog of 200,000 clusters•….

• See LSST white paper submitted to Dark Energy Task See LSST white paper submitted to Dark Energy Task Force, at http://www.lsst.orgForce, at http://www.lsst.org

• Neutrino masses probed toNeutrino masses probed to

(Wang et al PRL 94, 011302, 2005)(Wang et al PRL 94, 011302, 2005)

• Photometric redshift catalog to 26th magnitudePhotometric redshift catalog to 26th magnitude: : • Baryon oscillations• Catalog of 200,000 clusters•….

• See LSST white paper submitted to Dark Energy Task See LSST white paper submitted to Dark Energy Task Force, at http://www.lsst.orgForce, at http://www.lsst.org

mν∑ ~.3eV

48

Near Earth AsteroidsNear Earth AsteroidsNear Earth AsteroidsNear Earth Asteroids

• Inventory of solar system is incompleteInventory of solar system is incomplete• R=1 km asteroids are dinosaur killersR=1 km asteroids are dinosaur killers• R=300m asteroids in ocean wipe out a R=300m asteroids in ocean wipe out a

coastlinecoastline• Demanding project: requires mapping the sky Demanding project: requires mapping the sky

down to 24down to 24thth every few days, individual every few days, individual exposures not to exceed ~20 sec. exposures not to exceed ~20 sec.

• LSST will detect NEAs to 300m LSST will detect NEAs to 300m

• Inventory of solar system is incompleteInventory of solar system is incomplete• R=1 km asteroids are dinosaur killersR=1 km asteroids are dinosaur killers• R=300m asteroids in ocean wipe out a R=300m asteroids in ocean wipe out a

coastlinecoastline• Demanding project: requires mapping the sky Demanding project: requires mapping the sky

down to 24down to 24thth every few days, individual every few days, individual exposures not to exceed ~20 sec. exposures not to exceed ~20 sec.

• LSST will detect NEAs to 300m LSST will detect NEAs to 300m

49

Joint Dark Energy Mission (JDEM)Joint Dark Energy Mission (JDEM)Joint Dark Energy Mission (JDEM)Joint Dark Energy Mission (JDEM)Initial concept from LBL group for satellite Initial concept from LBL group for satellite dedicated to imaging and spectroscopy of dedicated to imaging and spectroscopy of supernovae: “SNAP”supernovae: “SNAP”

NASA solicited other proposals, 2 others selected NASA solicited other proposals, 2 others selected for concept studies:for concept studies:

““Destiny”: Infrared grism imaging of supernovae.Destiny”: Infrared grism imaging of supernovae.

““Adept”: H-Adept”: H- survey for baryon acoustic survey for baryon acoustic oscillations, plus SN photometry. oscillations, plus SN photometry.

Initial concept from LBL group for satellite Initial concept from LBL group for satellite dedicated to imaging and spectroscopy of dedicated to imaging and spectroscopy of supernovae: “SNAP”supernovae: “SNAP”

NASA solicited other proposals, 2 others selected NASA solicited other proposals, 2 others selected for concept studies:for concept studies:

““Destiny”: Infrared grism imaging of supernovae.Destiny”: Infrared grism imaging of supernovae.

““Adept”: H-Adept”: H- survey for baryon acoustic survey for baryon acoustic oscillations, plus SN photometry. oscillations, plus SN photometry.

51

Common ChallengesCommon Challenges Common ChallengesCommon Challenges

• Systematics! Systematics! • These are observations, not experiments.• Diversity of techniques is essential

• SoftwareSoftware• Real-time processing and transient classification• High-throughput image processing and data access• Database technology

• Precision Calibration of PhotometryPrecision Calibration of Photometry• Point Spread FunctionsPoint Spread Functions• Photometric redshifts Photometric redshifts • International astro-politicsInternational astro-politics• Multiagency/interdisciplinary support?Multiagency/interdisciplinary support?

• Systematics! Systematics! • These are observations, not experiments.• Diversity of techniques is essential

• SoftwareSoftware• Real-time processing and transient classification• High-throughput image processing and data access• Database technology

• Precision Calibration of PhotometryPrecision Calibration of Photometry• Point Spread FunctionsPoint Spread Functions• Photometric redshifts Photometric redshifts • International astro-politicsInternational astro-politics• Multiagency/interdisciplinary support?Multiagency/interdisciplinary support?

A Sobering Note… and 3 questionsA Sobering Note… and 3 questionsA Sobering Note… and 3 questionsA Sobering Note… and 3 questionsEvidence of Dark Energy seems compellingEvidence of Dark Energy seems compelling

Current data favor wCurrent data favor w1, w1, waa= 0= 0

1. What if this is the real answer? When do we quit? 1. What if this is the real answer? When do we quit?

2. How do we assign value to this parameter 2. How do we assign value to this parameter space, absent guidance from theory?space, absent guidance from theory?

3. What 3. What combinationcombination of ground and space-based of ground and space-based facilities is the most cost-effective approach? facilities is the most cost-effective approach?

Evidence of Dark Energy seems compellingEvidence of Dark Energy seems compelling

Current data favor wCurrent data favor w1, w1, waa= 0= 0

1. What if this is the real answer? When do we quit? 1. What if this is the real answer? When do we quit?

2. How do we assign value to this parameter 2. How do we assign value to this parameter space, absent guidance from theory?space, absent guidance from theory?

3. What 3. What combinationcombination of ground and space-based of ground and space-based facilities is the most cost-effective approach? facilities is the most cost-effective approach?

53

SummarySummarySummarySummary

Astrophysics is a fruitful avenue for exploring new Astrophysics is a fruitful avenue for exploring new fundamental physics fundamental physics Makes sense to go where the signal is!

Imperatives include Imperatives include Understanding the physics of an apparent non-zero Determining nature and distribution of dark matter Probing foundations of gravity

Next-generation facilities offer tremendous leap in Next-generation facilities offer tremendous leap in capability: Pan-Starrs, DES, LSST, SPT, JDEM….capability: Pan-Starrs, DES, LSST, SPT, JDEM….

Astrophysics is a fruitful avenue for exploring new Astrophysics is a fruitful avenue for exploring new fundamental physics fundamental physics Makes sense to go where the signal is!

Imperatives include Imperatives include Understanding the physics of an apparent non-zero Determining nature and distribution of dark matter Probing foundations of gravity

Next-generation facilities offer tremendous leap in Next-generation facilities offer tremendous leap in capability: Pan-Starrs, DES, LSST, SPT, JDEM….capability: Pan-Starrs, DES, LSST, SPT, JDEM….