The SIRTF SWIRE Survey SWIRE is a shallow/moderate depth survey of ~70 sq. degrees in all 7 SIRTF imaging bands 5  sensitivities: 17.5 mJy 160  m 2.75 mJy 70  m 0.45 mJy 24  m 32.5  Jy8.0  m 27.5  Jy5.8  m 9.7  Jy4.5  m 7.3  Jy3.6  m SIRTF is ideally designed for detailed study of the history of star formation MIPS is optimized for star-forming galaxies and AGN IRAC is optimized for old and/or reddened stellar populations

SWIRE Science Goals To enable fundamental studies of cosmology and galaxy evolution in the Mid- and Far-IR for 0.5<z<2.5: Evolution of star-forming and passively evolving galaxies with time in the context of structure formation models Spatial distribution and clustering of evolved galaxies, starbursts and AGN, and the evolution of their clustering Evolutionary relationship between galaxies and AGN, and the contribution of AGN accretion energy to the cosmic backgrounds

SWIRE Survey Design The 1 3 universe Galaxy evolution must be studied in the context of environment  SWIRE will sample: – Several hundred >100 Mpc co-moving volumes – Redshift range 0.5<z<2.5 – 7 target fields to combat cosmic variance

The SIRTF SWIRE Survey Plotting only every 10 th galaxy SFRs for galaxies; compared to integrated SFH (which is normalized by volume)

SWIRE Lockman Hole (preliminary pointing) Simulated Image; Shupe, Fang & Xu

The Power of the Mid-IR As the 7.7  m PAH feature redshifts into the 24  m filter  feature in the predicted f 24  m < 2mJy counts. Gordon et al.

IRAC Observation Plan For a 10 sq deg area, need 24 AORs for two coverages Each AOR: 1.75º x 30  6 columns by 21 rows, grid spacing 300   two cycling dithers at each map grid point Total coverage: 4x30 sec per point

MIPS Observation Plan Optimization at 24 and 70  m due to confusion limit at 160  m. Medium scan rate: 4 second exposures – 10x redundancy at 24 and 70 microns – filled 160  m map Two epochs – redundancy – asteroid/transient removal; destriping

The Importance of Field Selection: Schlegel et al DIRBE-calibrated IRAS 100  m map B 100 Contours at 1 and 2 MJy/sr |  |=45 contours Cirrus/N H /extinction must be minimized Seb Oliver

SWIRE Field Selection FIELDRA J2000 DecISSA MJy/sr E(B-V)Size Sq. deg ELAIS-S100h38m30s-44d00m00s< XMM-LSS02h21m00s05d00m00s Chandra-S03h32m00s-28d16m00s < Lockman Hole10h45m00s+58d00m00s< Lonsdale Hole14h38m00s +59d15m00s< ELAIS-N116h13m30s +55d16m00s< ELAIS-N216h36m48s +41d01m45s<

Sensitivity, Cirrus and Confusion Noise

Supporting Observations Optical, NIR: NOAO, ESO, Palomar, INT, 2dF, Keck Three Tiers: r'r'2570 sq deg g'r'i'Ksg'r'i'Ks 26 / 25 / 24 / g'r'i'g'r'i'27 / 26 / 253+

Supporting Observations Radio: Median predicted flux is 43  Jy Too deep for large area coverage Selected very deep VLA in small areas: 3  Jy rms 7.5  Jy rms X-ray: Selection wrt existing/planned deep Xray surveys: Lockman Hole Chandra-S ELAIS XMM-LSS

Anticipated Early SWIRE Results BRK magnitude distributions observations: Cohen et al. 2000, Hogg et al ISO 15  m sample of Aussel et al. (1999).

Photometric Redshifts

Examples of Additional Science made possible Hundreds of field brown dwarfs, especially T (“methane”) dwarfs circumstellar debris disks (to 100 pc), and HR4796A analogs to 1kpc Thermal emission at 8 and 24  m from main belt asteroids as small as 1km Serendipitous discoveries; rare objects to 1-in to 1-in-10 6

Identifying SIRTF Sources Confusion and cirrus noise dominate FIR/submm observations  Good complement comes from deep radio surveys to locate the UV-O-NIR counterparts – median SWIRE 20cm depth is ~ 75  Jy – impossible for VLA over large areas – the Square Kilometer Array can map: 1 sq deg 10 nJy rms, 24 hours or 1  Jy rms, 2 minutes mas beam

large scale structures 14Gyr – galaxy evolution – 2 Gyr AGN starbursts mergers SWIRE: – galaxies – AGN – hundreds of 100 Mpc-scale cells swire Kauffmann et al