NIRSSThe Near-Infrared Sky Surveyor

Daniel Stern, P.I.(JPL/Caltech)

Cosmic CartographyChicago, 2007 December

NIRDSSThe Near-Infrared Deep Sky Surveyor

Daniel Stern, P.I.(JPL/Caltech)

Cosmic CartographyChicago, 2007 December

Mark Brodwin (NOAO) Jason Kalirai (UC-Santa Cruz)

Asantha Cooray (UC-Irvine) Amy Mainzer (JPL/Caltech)

Roc Cutri (IPAC/Caltech) Leonidas Moustakas (JPL/Caltech)

Arjun Dey (NOAO) Jason Rhodes (JPL/Caltech)

Peter Eisenhardt (JPL/Caltech) Daniel Stern (P.I., JPL/Caltech)

Anthony Gonzalez (Univ. Florida) Edward L. Wright (UCLA)

submitted 2007 November 20in response to the

Astrophysics Strategic Mission Concept Studies (ASMCS; ROSES 2007)

~$8 M of design study money available, to provide robust and well-costed satellite mission concepts to the Decadal Survey;

selection expected in Jan./Feb. 2008

“medium class”(~$600 M)

~ 6 to be chosen

“large class”(> $1 billion)

~1-2 to be chosen

NIRSS will obtain full sky near-infrared images in four bands, reaching 1 μJy depths (24 mag, AB)

Images of GOODS-S field at 2.2 μm (K-band; 2.4 arcmin/side), obtained by 2MASS (left) and deep VLT/ISAAC observations (right). NIRSS will reach the same depth as the VLT observations,

with slight better spatial resolution

~600 times deeper than 2MASS at 2.2 μm (K-band)

Near-Infrared Surveys

compliments next generation of optical surveys (LSST & PanSTARRS)

All Sky (>2π ster) Surveys

clustered emission from first generation of star formation in the Universe;expected at near-infrared wavelengths (controversial claims already by Spitzer)

Goal #1: Diffuse IR Background from Pop III Stars

predicted number of high-redshift quasars from SDSS QLF (Fan et al. 2001, 2004)

Goal #2: The Most Distant Quasars

Redshift UKIDSS NIRSS

6<z<8 70-150 >100,000

8<z<10 1.3-2.6 ~10,000

10<z<12 0.02-0.1 150-300

12<z<15 – 2-18

simulated photometric redshift accuracy, assuming 4% floor

Goal #3: Stellar & Dark Matter Content of Galaxies

0 1 2 3 4z

0.0

0.1

0.2

0.3

0.4

0.5!

/(1+

z)

K(AB) < 23.9

Early Type

Late Type

ugrizy

ugrizyJ*H*K*L*

LSST alone

LSST + NIRSS

accurate (z>1) photometric redshifts aid weak lensing analysis by separating sources into redshift bins and differentiating background and foreground sources

Goal #3: Stellar & Dark Matter Content of Galaxies

optical CMD for NGC 6397 (globular cluster) from HST/ACS

Goal #4: The Coldest “Stars”

probing below thehydrogen-burninglimit (e.g., browndwarfs) in a range of environmentsthe coldest

white dwarfs

“Strawman” NIRSS Design

Primary Mirror Diameter: 1.4 meter (0.21” diff. limit at 1.2 μm)

Image Scale: 0.25”/pixel

Wavelength Coverage: 4 bands, 1-4 μm

Survey Depth: 1 μJy, full-sky

Optical Design: f/10.6 TMA

Launch Vehicle/Orbit: Delta IV / L2 orbit

Temperature: 65 K (passive cooling)

Mission Duration:2 yr. core mission4 yr. extended mission

“Strawman” Focal Plane Array (FPA)

Focal plane populated with nine JWST/NIRCam modules. Each module is comprised of four 2048x2048 Hawaii 2RG HgCdTe arrays, with each

quadrant observing a different bandpass. Total FOV is 1.6 deg in diameter.[Requirements on readnoise/dark current significantly reduced from JWST.]

Targets for JWST and TMT/ELT’s. Compliments Pan-STARRS/LSST + WISE.

Summary