Number of PhD

(1)

Experimental Cosmology in Taiwan

Paul Ho, ASIAA

(2)

Sketch of Talk

• Astronomy at ASIAA

• AMiBA Project

• CFHT WIRCam Project

• Subaru HSC Project

• CMB power spectrum, SZE Cluster physics

• High Z Surveys

• Weak Gravitational Lensing

• GMRT Re-ionization Studies

• Baryon Acoustic Oscillations

(3)

PERSONNEL at ASIAA

• 31 ASIAA Faculty (22 Regular, 9 Research)

• 11 Adjunct Faculty

• 23 Postdoctoral Fellows

• 14 Visiting Scholars

• 13 Ph.D. Students

• 16 Master Students

• 3 Undergraduate Students

• 7 Research Assistants

• 38 Technical Staff

• 23 Administrative Staff

Working Language:

Working Language: English English Staff:

Staff: ( Australia), Australia), Canada, Canada, (China), France, India, (China), France, India,

(4)

MAJOR ASIAA PROJECTS (2008)

SAO SMA : Array Completed, Upgrading

NTU AMiBA : 7-element Dedicated, 13-element underway NTHU TIARA; SIS Junction : 230, 345, 400, 690, 900 GHz NAOJ, PMO

NCU TAOS : 4 Telescopes Working; TAOS-2 YONSEI, SAO

ASIM CFD-MHD : 2-D Hydro Codes

CFHT WIRCam : Working well on Telescope

NAOJ ALMA-J : FEIC started; band-10

NRAO ALMA-NA: Approved; (FEHV?)

(5)

AMiBA Summary

• AMiBA is 1st CMB Telescope in Asia

• AMiBA is 1st Taiwan-Led Big Astronomy Project

• AMiBA is MoE CosPA Excellence Initiative

• Progress has been Very Fast (6 years)

• Project is Flagship of AS-University Partnership

• ASIAA Continues Strong Collaboration with NTU Physics and Electrical Engineering

• AMiBA is Operational, and currently Upgrading

(6)

PROJECT DESCRIPTION

• Science Objectives: CMB at l=800 to 8000

Polarization Power Spectrum and Structure High-Z Cluster Survey via SZE

Large Scale Structures via SZE

• Operations at 3mm ( suppress synchrotron, dust )

• 7-Element Dual Polarization Interferometer

• Funding: MOE, AS, NSC, NTU

Goals Set in 2005, after Project Reorganization

(7)

Polarization Power Spectrum Polarization Power Spectrum

WMAP Samples to l = 500

AMiBA will sample

Polarization Consistent With Temperature Structures

Reionization Signature Seen

(8)

Sunyaev Zel’dovich Effect

10 10 ' ' 10 10 ' ' 6 6 ' '

X-ray X-ray X-ray

(Carlstrom et al. 1999)

SZE brightness independent of distance (z), SZE brightness independent of distance (z),

while X

while X - - ray/Optical/ ray/Optical/ Lensing Lensing signal of clusters gets fainter signal of clusters gets fainter

μ μ

(9)

Timeline of AMiBA

• 2000-2004 MoE “Excellence” Funding

• 2003-2006 AS “Key Project” Funding

• 2004-2008 NSC “Continuation” Funding

• 2000-2002 Design, Prototype

• 2002-2005 Contracting, Construction

• 2006- Dedication, Operation

• 2007- First Science Results

• 2008- Publish or Perish!

• 2008- Upgrade to 13-elements

• 2009 10-element operations (30x faster)

13-element operations (2x faster)

(10)

Site Development in Hawaii

AMiBA

SMA

Construction

Cost Large

(11)

AMiBA Installed on Mauna Loa

(12)

Integration on Platform 2006

(13)

A Nice Day in Hawaii 10.2006

AMiBA

AMiBA Named after Yuan Named after Yuan Tseh Tseh Lee Lee

(14)

AMiBA First Image: Jupiter

Noise rms =~ 1Jy/beam (in 12s, 42 baselines)

Synthesized beam FWHM (6’)

September 8, 2006

12 scans combined at transit Net integration = “12s”

)]

( )

( [ )

( x ¹ S u V u I r = FT ⁻ r r

Dirty image Dirty image

Jupiter - 850Jy point source

End-to-end verification = hardware + software

(calibration, analysis

pipelines)

(15)

First SZE Detection towards

A2142 @z=0.09 (April 2007)

Estimated 3mm flux is about 300mJy, being consistent with the 30GHz observation by VSA at 1cm

About 6σ detection in 5hr x 2-Patch observations (2-3

P2

P1 P1-P2

(16)

Checking Gaussianity, Contamination,

Noise Behavior

(17)

A2142 A2163

A1995 A2261

More Clusters

(18)

SZE and Dark Matter

Dark Contour:

AMiBA SZE Color Plot:

Gravitational Mass White Bars:

Gravitational Shape Distortions

85-94% cross correlation found between WL and SZE maps, indicating that the cluster plasmas are tracing the DM

potential fairly well.

(19)

Cluster Hot-Baryon Fractions from AMiBA SZE & Subaru Weak Lensing

Joint

Joint “ “AMiBA AMiBA + Subaru + Subaru ” ” data, probing the gas/DM distribution data, probing the gas/DM distribution out to ~80% of the cluster

out to ~80% of the cluster virial virial **radius (r_200 =~ 0.8 * r_vir** radius (r_200 =~ 0.8 * r_vir) )

First

First gas mass fraction

measurements out to large radii without assuming

without assuming the hydro-static equilibrium assumption.

When compared to the WMAP 5yr constraint on the cosmic baryon fraction, our CDM-based halo

model (black, cross-hatched) shows

that ~83% (+/-18%) of the baryons

are in the hot plasma phase of

(20)

AMiBA: “Multi-λ Study of Clusters”

Subaru Rc-band image

DM contours X-ray contours

X-ray image Rc-band luminosity

DM vs. Baryons in A2142 DM vs. Baryons in A2142

Weak lensing, X-ray, and optical study of 7-merging clusters of galaxies by

Lensing + X-ray + Optical + SZE,

probing the cluster physics

(21)

A2142 SZE vs Weak Lensing

A2142 at z=0.091 FOV = 1.8 Mpc h ^-1 Merging Cluster with two X-ray cold fronts At 5’ angular resolution SZE shows shape

consistent with Dark Matter distribution.

NW enhancement may

be overpressure of ICM

(22)

Hubble Constant:AMiBA SZE + X-ray

Angular Diameter Distances (D

_A

) for original data (o) and corrected

H

₀

~ 1/D

_A

(23)

Improve Electronics, Add 6 Rx’s

Expand Correlator, 1.2m Dishes

(24)

7 1.2m Reflectors Installed

(25)

7 1.2m Reflectors Installed

(26)

WIRCam Deployed on CFHT 2006

Wide Field (20’)

Images with 4 HgCdTd

Detector Arrays

(27)

CFHT 2008

Will continue to access CFHT at a minimum of 10 nights per year

Will continue to work with CFHT on AO, spectro-polarimeter projects

(28)

Search for the High-z galaxies

z Pushing the redshift limits of high-redshift galaxies are essential in:

9 quantifying the contribution of early star formation to cosmic

reionization

9 characterizing the history of cosmic star formation rates 9 probing the formation mechanism and evolutionary path of

early galaxies

z To date most candidates at z>7 are selected in extremely deep pencil beam surveys with very small areas, but none has been spectroscopically-confirmed yet.

z=4

z=7-8

Dropout (or Lyman-Break) Technique

The populations and properties of z>7

galaxies are still poorly understood !

(29)

Probing the Dark Age

A Deep WIRCAM J Survey for z>7 Galaxies in the ECDF-S

Search for z’-dropout candidates at z>7 Field: Extended Chandra Deep Field-South 5X wider than published survey

ACS v & z’ band and IRAC data are public Contaminators (color-color diagram):

Galactic objects: blue area low-z galaxies: thin solid lines

Red area for z>7 z’-dropout candidates

Two excellent candidates are found ECDFS ZD1: J=24.92

ECDFS ZD3: J=24.42

Not seen in deep space-based opt data detected in all bands redder than z’

SED fittings give photo-z=7.2 Estimated stellar mass: 10

^10.3

M

☉

(not predicted by cosmological model)

(30)

z-dropout candidates (z>7 galaxies) found in GOODS-N

Proposing HST/NIC3 study to follow up on these candidates.

– If null detections: an stringent upper limit of bright z>7 galaxies would be set.

– If positive detections: we will look for spectroscopic confirmations.

ACS i775 ACS z850 WIRCAM J IRAC [3.6]

Joint CFHT program between Taiwan and Canadian (06A, 07A, 09A)

Taiwan: 52 hrs in J

Canada: 10 hrs in K (plus 70+ hrs in K

taken by the Hawaiian group)

People:

Taiwan: L. Lin, C. Yan, Y. Cheng, S.

Wang

External: H.Yan, M. Dickinson, N.

Meger, A.

Pope, D. Koo, D. Scott, L. Simard

(31)

Red-sequence Cluster Survey 2

Covering 1000 deg ²

Using CFHT MegaCam (g’, r’, & z’) 10 ⁴ galaxy clusters will be found

Survey Design Science Goal

Providing constraints in the w-Ω m plane Discovering 50-100 strong lensing clusters

Current Status

Supernovae 200 Supernovae 400 MAP (CMB)

PLANCK (CMB)

Cluster mass function

(z<1.2, 1000 deg

²

, Tx>5Kev) 200 SNe + MAP + Clusters

Levine et al. 2002, astro-ph/0204273

International collaboration (Canada, USA, Taiwan, & Chile)

(32)

ASIAA Joins Subaru

Hyper SuprimeCam Project 10.08

1.5 degree FOV, 10 x FOV (Surpime Camera) 25 M USD Budget (Taiwan 5M) , 5 year timescale ASIAA: Detector Electronics, Shutter, Filter Exchanger Weak Lensing Tomography; z>6

Weak Gravitational Lensing: Cosmic Shear

Dark Matter Visible Clusters

ARL designing shutter, filter exchanger

(33)

Many Science Targets for HSC

(34)

z neutral hydrogen: most abundant element

z optically thin through out the universe

z line transition: gives 3D information

z visible from 0 < z < ~150, when Ts decouples from Tcmb

z ~20 < z < 150, Ts < Tcmb, 21cm in absorption

z 0 < z < ~15, Ts > Tcmb, 21cm in emission

21cm Cosmology

absorption z emission

~6 ~20 ~150

0 HI

reionization

(35)

The 21cm universe

• Up to 10

¹⁸

modes to z=50 (Hubble/Jeans)

³

• Physics: Lensing, gravity waves, primordial NG, BAO, AP

• Astrophysics: EoR, galaxy evolution

• Experiments NOW – EoR : GMRT

– BAO : GBT/CHIME

EoR: GMRT

CHIME/

GBT

SDSS

(36)

• Astrophysical -- probing the Epoch of Reionization (EoR):

– Traditional observation can’t see anything before there were luminous matter

– Can probe full ionization structure (Ly-alpha saturates except at the end of reionization)

• Precision cosmology -- measuring cosmological parameters:

– at high z, pre-reionization: linear, 10 ¹⁸ modes; much more than the CMB (10 ⁷ ), LSS (10 ⁷ at z<1)

– at low z, “ionized”: use HI intensity mapping to make an efficient redshift survey: Baryon Acoustic

Oscillation measurements; Lensing (T.T. Lu, O. Dore, U. Pen)

Why 21cm?

(37)

GMRT - Giant Meterwave Radio Telescope

(38)

Foregrounds

150K - 200 K;

100 hrs observation

(39)

GMRT Current Status

Sensitivity forecast promising

Installed software RFI mitigation

successful;

physical

elimination under investigation

Pulsar phase referencing

successful

No polarized point sources

found

Upper limits on polarized foregrounds ~ 1K Foreground

subtraction

underway

(40)

BAO - Tool for Precision Cosmology

(41)

• HI BAO Experiment Prospects

• CHIME (Canadian Hydrogen Intensity Mapping

Experiment); Cosmic Variance limited Hubble Survey

(42)

MANPOWER in Taiwan

No. of PhD working in Astronomy, Astrophysics & Particle Astrophysics in Taiwan

3 4 10 14 16 20 25

34 36

44 44 52

66 70 75 82 82

94 95

107 113

0 20 40 60 80 100 120

1970's1980~851986~90 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008