The Science Cases for CSTAR, AST3, and KDUST

Lifan Wang

CCAA & TAMU

CSTAR

• A pathfinder telescope

• Sky background and transmission

- See Zhou Xu’s talk

• Time domain astronomy

- Variable stars

• A wide area polarization map

of nearby bright stars

Variable Stars from CSTAR

Credit: Lingzhi Wang, TAMU/BNU

Credit: Lingzhi Wang, TAMU/BNU

An RR Lyrae Star

Uninterrupted 4.5-d light curve (representing 3.5% of the entire data).

Folded light curve of the data on the left using P = 0.6466d; the photometric uncertainty is 3 mmag/bin.

RR Lyrae star Y Oct

d Scuti star

Uninterrupted 4.5-d light curve (representing 3.5% of the entire data).

Folded light curve using P = 0.2193d; the photometric uncertainty is 1.5 mmag/bin.

A Long-period (P~116.7d) Variable

Using the ASAS period as a starting point, the dominant periodicity was fit using a a five-term Fourier expansion fit. Left: the original data; Right, residual light curve, showing a small-amplitude (< 0.01 mag) periodicity with P = 17.3 d.

An Exoplanet Candidate

Black dots: Raw data Red dots: Data binned to 10 min interval

One of previous design

1) Adjustable tower height (preliminary designed to be about 1.5m);

2) Foldable dome;

3) Active snow removing;

4) Auto-focusing.

AST3

Transportation and assembly at Dome A

Standard size container (about 2991×2591×2438mm)

AST3

• Supernovae - Very early discovery - Uniform multicolor light curve coverage • Planet transients - Transients - Microlensing • LMC - Novae - Microlensing • Variable stars

AST3 Schedule: Installation in 2011-2012 Survey Operation: 2012 – 2017 Data Products:

>2000 SNIa to z ~ 0.15 Core-collapse Sne; GRB; Orphan GRB afterglow

LMC continuous monitoring –variable stars/microlensing/dark matter Galactic center continuous monitoring – variable stars/microlensing/transients Galactic structure – RR Lyrae/Cepheids

SPT overlap area

SDSS Southern Equatorial Stripe

Tie region

KDUST 2.5

Observational Mode: Wide Area Survey Scientific Objectives: Dark Universe, Exoplanets Scientific Methods: Gravitational Lensing, Supernovae, and Precision Photometry Construction Period: 2011-2015 Cost: RMB 230 million

Survey Area

5000 deg2 Cosmological Survey

Overlaps with South Pole Telescope

1% photometric precision

SPT overlap area

SDSS Southern Equatorial Stripe

Tie region

KDUST2.5 Data Products

• 5000 sq degree high resolution image survey • 0.1-0.15 arcsec/pixel • 0.3 arcsec FWHM

• 10,000 sq deg K-Dark (2.4 micron) survey to KAB = 27mag

• ~ 5,000 SNIa to z ~ 3; PPSN search to z ~ 7

• LMC/SMC high cadence survey

• Galactic center K-Dark survey

• Cepheids in nearby galaxies – Hubble constant

Synergistic Considerations

• CSTAR – Kepler/Corot/Other small telescopes

• AST3 – VLT Xshooter/Other telescope arrays/Other small telescopes

• KDUST2.5 – TMT/ELT/JWST

The Construction of the Antarctica Observatory at Dome A may become one of the most remarkable achievements of the human race

Study of the Early Universe with KDUST

Xuelei Chen (NOAC)

Wei Zheng (JHU)

August 17, 2010, XiAn

August 17, 2010, XiAn

Epoch at Redshift z>7

• Reionization of the IGM

• First generation of black holes

• Rapid star formation

August 17, 2010, XiAn

Kunlun Station at Dome A

August 17, 2010, XiAn

Spectra of Quasar at z~6

White et al. 2003

August 17, 2010, XiAn

Number of Quasars

August 17, 2010, XiAn

Reionization of the IGM

Fan et al. 2006

August 17, 2010, XiAn

Requirements

At least 5000 square degrees

YJHK bands

Limiting magnitude AB=24

August 17, 2010, XiAn

Supernovae of Population III

• Massive: 100-250 solar mass

• Pair-instability outburst

• Bright: M~-24

• Metal free

August 17, 2010, XiAn

SCP 06F6

Quimby et al. 2009

Peak brightness of 250 M PISNe as a function of redshift in the spectral region around Ly-alpha assuming both no significant extinction and the "worst case" extinction for the Ly region

An Example KDUST K-Dark Science

August 17, 2010, XiAn

Surface Density of PISN

Weinmann & Lilly 2005

August 17, 2010, XiAn

Requirements

Repeated observations over 10 square degrees

Cadence of ~1-3 months

Magnitude AB>26

August 17, 2010, XiAn

Gamma Ray Bursts

Detectable at very high redshift

Peak magnitude AB~20

August 17, 2010, XiAn

GRB at z=8.3

Tanvir et al. 2009

August 17, 2010, XiAn

Requirements

Fast communication link

Fast slew capability (within minutes)

Low- or medium-resolution spectrograph

August 17, 2010, XiAn

Summary

KDUST is a powerful in high-z studies

Complimentary to JWST, TMT

Need both wide and deep surveys