Checking the consistency ofgrowth and expansion with theDark Energy Survey

DARK ENERGYSURVEY

Jessie Muir
KIPAC @ Stanford
Collaborators: Vivian Miranda, Eric Baxter, Dragan Huterer, Bhuv Jain

Oct. 7, 2019. Cosmic Controversies, KICP, Chicago
Photo credit: Ross Cawthorn (Wisconsin)

Our goal is to learn about fundamental physics
by testing the predictions of ΛCDM.
DARK ENERGYSURVEYΛCDM:
composition

Initial fluctuation
properties
gravity

Jessie Muir (Stanford)• Dark energy as acosmological constant (Λ)• CDM: Cold dark matter• Flat geometry: ΩΛ + Ωm = 1• Gaussian initial fluctuations
w. nearly scale-invariant
power spectrum (As, ns)• Gravity described byGeneral relativity
2Our goal is to learn about fundamental physics
by testing the predictions of ΛCDM.
DARK ENERGYSURVEYΛCDM:
composition

Initial fluctuation
properties
gravity

Jessie Muir (Stanford)• Dark energy as acosmological constant (Λ)• CDM: Cold dark matter• Flat geometry: ΩΛ + Ωm = 1• Gaussian initial fluctuations
w. nearly scale-invariant
power spectrum (As, ns)• Gravity described byGeneral relativity
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DARK ENERGYSURVEY

DES-Planck comparison tests consistency ofearly- and late-time Λ CDM predictions.
Early-time CMB
measurementsPlanck• Abbott et al,arXiv:1708.01530

Late-time structure
measurementsfrom DES
Jessie Muir (Stanford)

Results from DES

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DES constraints on extended models test forphenomenological deviations from LCDM.
DARK ENERGYSURVEY<- galaxy clustering

Results from DES Y1
Galaxy Clustering andWeak Lensing,arXiv:1810.02499<- lensing(dashed line: LCDM)

DES:• Y1 galaxy clustering
and weak lensing
Ext:• Planck TT + lowP
• BAO from BOSS
DR12, 6DF, SDSS MGS• Pantheon SNeContributors include: Agnes Ferte, Danielle Leonard, Lucas Secco, Andresa Campos, Otavio Alves, AndersonSouza, Jack Elvin-Poole, Pablo Lemos, Sujeong Lee, Cyrille Doux, Ian Harrison, Eleonora Di Valentino, NoahWeaverdyck, Angela Chen, Marco Raveri, Vivian Miranda, Dragan Huterer, Scott Dodelson, Andrew Liddle, ++5

Growth-geometry split
DARK ENERGYSURVEY• Goal: Test consistency of cosmological constraints from expansion history(geometry) and structure growth.
• Motivation: Extensions to LCDM can break the one-to-one relationship between
structure growth and expansion history in LCDM.
• Method:• Split cosmological parameters related to dark energy properties into “grow”
and “geo” versions.
• Constrain simultaneously, check consistency with grow = geo

Jessie Muir (Stanford)

Wang et al 2007, arXiv:0705.0165
Ruiz and Huterer, 2014, arXiv:1410.5832
Bernal, Verde, an Cuesta 2016, arXiv: 1511.03049

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Growth-geometry split analysis of DES Y1 dataDARK ENERGYSURVEYLCDM model splitting just Ωm
DES ”Year 1 all”

Y1 galaxy clustering + weak lensing(3x2pt) [grow+geo]
Y1 BAO [geo]Y3 SN [geo] + lowZ SN“Ext geo” [geo]BOSS DR12 BAO
Planck 5D Gaussian likelihood forAs, ns, Rshift, Ωbh2, lA

Ext geo [geo] + RSD [grow]
BOSS DR12 RSD

Jessie Muir (Stanford)

Collaborators:
Vivian Miranda, Eric Baxter, Dragan Huterer, Bhuv Jain

7DARK ENERGYSURVEY

Understanding
degeneracies

DES ”Year 1 all”

Y1 galaxy clustering + weak lensing (3x2pt)[grow+geo]
Y1 BAO [geo]Y3 SN [geo] + lowZ SN

Ext geo [geo] + RSD [grow]
BOSS DR12 RSD

Jessie Muir (Stanford)

8For consistency checks and extended model
constraints, we need to understand systematics.
DARK ENERGYSURVEY

Jessie Muir (Stanford)

9Blinding as a tool for robust analyses
DARK ENERGYSURVEY• DES Y1: blinded at parameterlevel until set of unblinding
criteria are passed.
• DES Y3: new method ofblinding by modifying
summary statistics (2PCF).
• Methods paper (Muir et al.
2019) in DES internal review.
• Collaborators: Gary Bernstein,
Dragan Huterer, Franz Elsner

Jessie Muir (Stanford)

Synthedattica10

Summary and outlook
DARK ENERGYSURVEY• Growth-geometry split is a physicallymotivated consistency test of LCDM.

• Introduces few new parameters.
• ~ model independent• DES & external data will provide
complementary information for this test.

• Cautionary notes• Not a physical model.
• Look-elsewhere effect in model-space• Results to come soon!

Full footprint

Y1 footprint• Currently preparing to run growth-geometry
split pipeline on Y1 DES data.
• DES Y3 galaxy clustering and weak lensing
analysis will increase constraining power.
Jessie Muir (Stanford)

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Backup slides

Jessie Muir (Stanford)

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Previous growth-geometry split results:
Ruiz and Huterer 2014 (1410.5832)
DARK ENERGYSURVEYLCDM model, splitting Ωm(fixed mnu)

Jessie Muir (Stanford)

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Previous growth-geometry split results:
Bernal, Verde, and Cuesta 2016 (1511.03049)
DARK ENERGYSURVEYwCDM model, splitting Ωm(fixed mnu)
Constraints from:
CMB TT, TE, EE, JLA Sne, BAO,RSD, cluster abundance

Jessie Muir (Stanford)

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DES observables are sensitive to both growthand geometry.
DARK ENERGYSURVEY

Angular correlation forz-bins i & j for A-B =• Galaxy-galaxy

Redshift distribution ofsources, lensing kernel• Shear-shear• Galaxy-shear

Power spectrum ofmatter density
fluctuations

Projection onto the sky

Normalized counts

8Lenses7

redMaGiC

65432
1

Normalized counts

0M ETACALIBRATION

432
100.0Jessie Muir (Stanford)

Sources

50.2

0.4

0.6

0.8
1.0Redshift

1.2

1.4

1.6

1.815

Growth-geometry split analysis of DES Y1 data
DARK ENERGYSURVEY DES ”Year 1 all”

Y1 galaxy clustering + weak lensing (3x2pt)[grow+geo]
Y1 BAO [geo]Y3 SN [geo] + lowZ SN

Jessie Muir (Stanford)

wCDM model splitting both w and Ωm“Ext geo” [geo]BOSS DR12 BAO
Planck 5D Gaussian likelihood forAs, ns, Rshift, Ωbh2, lA

Ext geo [geo] + RSD [grow]
BOSS DR12 RSD16

Previous growth-geometry split results:Bernal, Verde, and Cuesta 2016 (1511.03049)
DARK ENERGYSURVEY

Jessie Muir (Stanford)

wCDM model, splitting either just w or just ΩmConstraints from: Planck 2013/5 CMB TT, TE, EE, JLA
Sne, BAO, RSD, cluster abundance

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The Dark Energy Survey

Funded by

DARK ENERGYSURVEY• See also: Gary’s talk from Sunday• 5000 sq. degree imaging survey using
4m Blanco telescope @CTIO• 10 exposures in 5 colors• 6 years of observing ended Jan. 2019

• Probes: large scale structure,
supernovae, galaxy cluster counts, weakgravitational lensing• Y1: 1300 sq. deg at 40% depth• 13+ papers published of results starting in2017• Y3: 5000 sq. deg, 50% depth• Data processed, analysis in progress

Full footprint

Y1 footprint

Full footprint

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Jessie Muir (Stanford)

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