Gong-Bo ZhaoICG, Portsmouth

1106.3327 (PRL submitted)

1105.0922 (PRL 11)

1011.1257(PRD 11)

1005.3810 (PASP 11)

0905.1326 (PRL 09)

Understanding the Cosmic Acceleration using KDUST

My main collaborators

Robert Crittenden (Portsmouth), Zuhui Fan (PKU)Aireza Hojjati (SFU), Kazuya Koyama (Portsmouth)Baojiu Li (Durham, Cambridge),Yinzhe Ma (UBC,

Cambridge)Jeremiah Ostriker (Princeton, Cambridge), Levon Pogosian (SFU) Alessandra Silvestri (MIT), Lifan Wang (TAMU), Hu Zhan

(NAOC) Xinmin Zhang (IHEP)

Nov 9, 2011KDUST workshop, IHEP, Beijing

Nov 9, 2011KDUST workshop, IHEP, Beijing

Nobel Prize, 2011

Cosmic Acceleration

Nov 9, 2011KDUST workshop, IHEP, Beijing

DE MG

Nov 9, 2011KDUST workshop, IHEP, Beijing

Weak LensingWeak

Lensing

Galaxy CountsGalaxy Counts

ISWISW

KDUST

KDUST is useful for DE

Nov 9, 2011KDUST workshop, IHEP, Beijing

Nov 9, 2011KDUST workshop, IHEP, Beijing

LSST 15000 sq. deg. UgrizyGBZ, H.Zhan, L. Wang, Z. Fan, X.Zhang, 1005.3810, PASP

11

15000 sq. deg.:n(z) ~ z2exp(-z/0.5)Photo-z rms: z=0.04(1+z)Photo-z bias prior: P(z)=0.2z

Shear calibration error: ±0.003Residual shear power: 6×10-10

Nov 9, 2011KDUST workshop, IHEP, Beijing

5000 sq. deg.:n(z) ~ z2exp(-z/0.6)Photo-z rms: z=0.03(1+z)Photo-z bias prior: P(z)=0.2z

Shear calibration error: ±0.002Residual shear power: 4×10-10

15000 sq. deg.:n(z) ~ z2exp(-z/0.5)Photo-z rms: z=0.04(1+z)Photo-z bias prior: P(z)=0.2z

Shear calibration error: ±0.003Residual shear power: 6×10-10

KDUST JH + LSST ugrizy

Nov 9, 2011KDUST workshop, IHEP, Beijing

10000 sq. deg.:n(z) ~ z2exp(-z/0.6)Photo-z rms: z=0.03(1+z)Photo-z bias prior: P(z)=0.2z

Shear calibration error: ±0.002Residual shear power: 4×10-10

10000 sq. deg.:n(z) ~ z2exp(-z/0.5)Photo-z rms: z=0.04(1+z)Photo-z bias prior: P(z)=0.2z

Shear calibration error: ±0.003Residual shear power: 6×10-10

KDUST JH + LSST ugrizy

Nov 9, 2011KDUST workshop, IHEP, Beijing

5000 sq. deg.:n(z) ~ z2exp(-z/0.6)Photo-z rms: z=0.03(1+z)Photo-z bias prior: P(z)=0.2z

Shear calibration error: ±0.002Residual shear power: 4×10-10

15000 sq. deg.:n(z) ~ z2exp(-z/0.5)Photo-z rms: z=0.04(1+z)Photo-z bias prior: P(z)=0.2z

Shear calibration error: ±0.003Residual shear power: 6×10-10

KDUST JH + LSST ugrizy

SNe: (z < 1.5)

KDUST—LSST Synergy KDUST—LSST Synergy credit: Hu Zhancredit: Hu Zhan

Nov 9, 2011KDUST workshop, IHEP, Beijing

Reconstructing w(a) precisely

R.Crittenden, GBZ, L.Pogosian, L.Samushia, X.Zhang To appear soon see Levon’s talk

Straightforward to apply to KDUST data!

KDUST is useful for MG

Nov 9, 2011KDUST workshop, IHEP, Beijing

On linear scale

PCA (see Levon’s talk)Cosmic Mach Number

Nov 9, 2011KDUST workshop, IHEP, Beijing

arXiv: 1106.3327

with

Yinzhe Ma (UBC, Cambridge)

Jeremiah Ostriker (Princeton and Cambridge)

Cosmic Mach Number: A robust tool to test Einstein Gravity

What is Mach Number??

Nov 9, 2011KDUST workshop, IHEP, Beijing

Cosmic Mach Number (CMN) Ostriker & Suto 1990

Nov 9, 2011KDUST workshop, IHEP, Beijing

Nov 9, 2011KDUST workshop, IHEP, Beijing

The shape of velocity power spectrum can be reconstructed from CMN

Nov 9, 2011KDUST workshop, IHEP, Beijing

CMN data

Cosmological applications

Nov 9, 2011KDUST workshop, IHEP, Beijing

Nov 9, 2011KDUST workshop, IHEP, Beijing

WMAP7 + UNION2 +CMN (6dF)

Power of CMN

B0<0.4 (95% CL, CMB+SN)B0<5x10-5 (95% CL, CMB+SN+CMN)

Nov 9, 2011KDUST workshop, IHEP, Beijing

CMN is a promising tool Immune to galaxy bias, overall amplitude,

nonlinearitiesHighly sensitive to the scale-dependence of the

growth, thus an ideal tool to constrain MG parameters and neutrino mass

Complimentary to weak lensing Measure CMN from KDUST??

Nov 9, 2011KDUST workshop, IHEP, Beijing

On Non-linear scale

Environmental dependence of dark matter halos

Nov 9, 2011KDUST workshop, IHEP, Beijing

f(R) Gravity

Nov 9, 2011KDUST workshop, IHEP, Beijing

Mimic GR at high z;

Accelerate the expansion at low z;

Recover GR locally to pass solar system test.

In GR

Nov 9, 2011KDUST workshop, IHEP, Beijing

In f(R)

Nov 9, 2011KDUST workshop, IHEP, Beijing

C

In very dense regions

Nov 9, 2011KDUST workshop, IHEP, Beijing

C

12 billion years ago

10 billion years ago

8 billion years ago

Now

Numerical Simulations 1011.1257 GBZ, B.Li, K.Koyama, PRD 11

Code: Modified MLAPMf(R) model:

Model parameters:

Cosmological parameters: WMAP7

Nov 9, 2011KDUST workshop, IHEP, Beijing

Equations to solve in the code

Nov 9, 2011KDUST workshop, IHEP, Beijing

Nov 9, 2011KDUST workshop, IHEP, Beijing

Get some sense…

Nov 9, 2011KDUST workshop, IHEP, Beijing

GR

Nov 9, 2011KDUST workshop, IHEP, Beijing

f(R)

Structure formation in GR

KDUST workshop, IHEP, Beijing Nov 9, 2011

Structure formation in f(R)

KDUST workshop, IHEP, Beijing Nov 9, 2011

Dynamical Mass

KDUST workshop, IHEP, Beijing Nov 9, 2011

Dynamical Mass

KDUST workshop, IHEP, Beijing Nov 9, 2011

Dynamical Mass

KDUST workshop, IHEP, Beijing

Spherical symmetry

Nov 9, 2011

Lensing Mass

KDUST workshop, IHEP, Beijing Nov 9, 2011

Lensing Mass

KDUST workshop, IHEP, Beijing Nov 9, 2011

Lensing Mass

KDUST workshop, IHEP, Beijing

Spherical symmetry

Nov 9, 2011

KDUST workshop, IHEP, Beijing

Mass Difference

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

In underdense environment

Nov 9, 2011

KDUST workshop, IHEP, Beijing

In underdense environment

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

In dense environment

Nov 9, 2011

KDUST workshop, IHEP, Beijing

In dense environment

The halos are screened so that they cannot feel the enhancement of gravity!

Nov 9, 2011

How to define “Environment”?Number of neighbours in spheres of radius RMass or density in spheres of radius RMatter density in spherical shellsAverage mass density of surrounding halosDistance to nearest halo with minimum massProjected galaxy number density out to the

Nth nearest neighbourwith a maximum radial velocity…

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Haas et al., 1103. 0547

All these quantities strongly correlate with halo mass!

Nov 9, 2011

To see the pure environmental effect, we need a new environment indicator which is uncorrelated with halo mass

KDUST workshop, IHEP, Beijing

The three-dimensional distance to the Nth nearest neighbour with a viral mass that is at least f times that of the halo under consideration, divided by the virial radius of the Nth nearest neighbour:

Haas et al., 1103. 0547

Nov 9, 2011

KDUST workshop, IHEP, Beijing

Small DAffected by the local environment

Nov 9, 2011

KDUST workshop, IHEP, Beijing

Small DAffected by the local environment

Large DAffecting the local environment

Nov 9, 2011

KDUST workshop, IHEP, Beijing

GR analysis, Haas et al., 1103. 0547

D is a clean indicator for the local environment!

Nov 9, 2011

KDUST workshop, IHEP, Beijing

f(R) analysis, 1105.0922GBZ, Baojiu Li, Kazuya Koyama (PRL 2011)

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Similar pattern!!

Nov 9, 2011

KDUST workshop, IHEP, Beijing

Similar pattern!!

The screening is only determined by the halo mass for the isolated halos!

Nov 9, 2011

KDUST workshop, IHEP, Beijing

Different pattern

Nov 9, 2011

KDUST workshop, IHEP, Beijing

Different pattern

The screening of the clustered halos is not determined by the halo mass only!

Nov 9, 2011

KDUST workshop, IHEP, Beijing

Different pattern

Environmental Effect!!

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Clean mass dependence!

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Large scatter shows the environmental effect!!

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Apparent environmental dependence!!

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

No screening at all!!

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

No screening!

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Maximum screeningCore is better screened

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Screened purely by environment

Nov 9, 2011

KDUST workshop, IHEP, Beijing Nov 9, 2011

KDUST workshop, IHEP, Beijing

Screening on the edge shows environmental dependence! Nov 9, 2011

Observationally…

KDUST workshop, IHEP, Beijing

Lensing Mass

Dynamical Mass

Nov 9, 2011

Measure lensing and dynamical mass for each halo;Divide the sample using D;Compare!

KDUST workshop, IHEP, Beijing Nov 9, 2011

Measure lensing and dynamical mass for each halo;Divide the sample using D;Compare!

KDUST workshop, IHEP, Beijing

Apply to KDUST data?!

Nov 9, 2011

Summary and Outlook KDUST is powerful to constrain DE

and MG by measuring SN, WL, BAO;

KDUST is powerful to constrain MG by measuring CMN, lensing and dynamical mass of galaxies;

KDUST can do more science, RSD, ISW, etc

Nov 9, 2011KDUST workshop, IHEP, Beijing