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Scientific Projects with ASTRO-F. Presented by Hyung Mok Lee (Seoul National University, Korea). 1. Outline of ASTRO-F. Purpose of the Mission To carry out all-sky survey at Far-Infrared Near and Mid Infrared Obs. of selected skies Launch Early 2004 by M-V Rocket (solid fuel) Orbit
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Scientific Projects with ASTRO-F Presented by Hyung Mok Lee (Seoul National University, Korea)
1. Outline of ASTRO-F • Purpose of the Mission • To carry out all-sky survey at Far-Infrared • Near and Mid Infrared Obs. of selected skies • Launch • Early 2004 • by M-V Rocket (solid fuel) • Orbit • Sun-Synchronous (like IRAS) • Altitude 700-900 km
Mission Structure • Science mission of ISAS, Japan • Partners • Seoul National University, Korea (Simulation and FIS Data reduction) • European Consortium led by M. Rowan-Robinson (FIS Source detection/confirmation) • ESA (pointing reconstruction/telemetry)
Telescope • Mirror • 68 cm, F/6 • SiC • 1" Quality • Cryogenic System • 170 liter LHe + Stirling Cooler • Life = 550 Days • T(tel) = 5.8 K, • T(detector) = 1.8 K (st. Ge:Ga), 15 K (InSb)
Focal Plane Instruments (1) • IRC: Near- and Mid-IR Camera • FIS:Far-IR Surveyor
Observation Mode • Max Pointings3 / revol. • Pointing Observation time < 10 min per orbit
Surveys with ASTRO-F • All-Sky Survey • FPI FIS • Wavelength Band 50 - 200 m • Sky Coverage 40000 sq. deg. • Wide Band Detectivity (5) 10 - 50 mJy • Pixel Size 30 -50 arcsec • Selected Sky Survey • FPI IRC(NIR) IRC(MIR) FIS • Wavelength Band 2-5 m 5-25 m 50-200 m • Sky Coverage 100 sq. deg. 100 sq. deg. 10 sq. deg. • Wide Band Detectivity (5) 1 - 2 Jy 20 - 100 Jy 0.8 - 50mJy • Line Detectivity (5) 3-7 x 10-19 Wm-2 3-6 x 10-18 Wm-2 2-3 x 10-17 Wm-2 • Pixel Size 1.2 arcsec 2.4 arcsec 30 - 50 arcsec
FIS Performance Channel 60 micron Wide-S Wide-L 170 micron Band 50-70 50-100 100-200 150-200 Pixel Pitch 30” 30” 50” 50” Array Configuration 2x20 3x20 3x15 2x15 Detection Limit (5) 20 15 40 60 (Survey) Detection Limit (5) 0.8 7 30 50 (Pointing) Field of View 8 arcmin in Cross-Scan (Arrays are Tilted by 26.5 deg.) Operation Mode Continuous Wide-band Survey -------All-sky Survey Pointed Wide-band Imaging -----------Deep FIR Imaging Pointed Spectroscopy -------------------FIR Spectroscopy Total Weight 5 kg (Cold Part only) Temperature 3K(Optics), 1.8K(Stressed Array) Heat Dissipation 3 mW @ 2K
All-Sky Survey Scan • Tilted Configuration for Nyquist Sampling in Both Directions ]
Observing Schedule Checkout (~20days) FIS all-sky survey No. of IRC pointings: 8.4/day(mainly for Ecliptic Pole regions) → total 1500 pointings Phase 1 (180 days) Mainly Pointing obs. + Suppl. FIS survey No. of IRC pointings: 19.7 /day → total 5900 pointings Phase 2 (~300 days) (L He boil-off) Phase 3 (>365 days) NIR observations No. of IRC pointings: 28.8 /day → >10500
ASTRO-F All-Sky Survey Products (Tentative) • Products • ASTRO-F Flux Catalog at IRAS Point Sources (PSC & FSC) • ASTRO-F Point Source Catalog at High Latitudes • ASTRO-F Point Source Catalog at Low Latitudes • ASTRO-F All-sky Images • IRC data reduction is responsibility of the observer
Proposed Projects • Evolved Stars (Circumstellar matter, etc) • Star Forming Regions • Interstellar Medium (SNR, other diffuse clouds) • Galaxy Evolution • Clusters of Galaxies • Galaxy Formation • Large Scale Structure
Galaxy Evolution: IRC ultra deep survey toward NEP • NEP and SEP have very good visibility • LMC near SEP
A possible Scenario of massive Elliptical Formation & Evolution Major Merger Galactic Wind Passive Evolution Phase Building Blocks (clumps) Dusty ULIRG Phase !!
Normal Galaxies Starburst Galaxies IRC Deep Survey Predictions(1) 3200sq.arcmin. NEP Deep Survey MIR wavelengths (Narrow Band Filters) Pearson, C. P., Matsuhara, H., Onaka, T., Watarai, H., and Matsumoto, T.(2001) Mon. Not. R. Astron. Soc., (astro-ph/0008472 ) Pearson, C.P. (2001) MNRAS, astro-ph/0011335)
Stellar Mass Assembly using NIR channel L* galaxies are detectable even at z=3!
Search for High-z Clusters • Environmental effects • Tidal force due to the cluster potential • Strong ram pressure due to intra-cluster medium • star formation history may be different from that of field galaxies • Galaxies in high-z clusters may be in dusty starburst phase and detectable for ASTRO-F
Rapid decline of SFR in the Cluster Environment Kodama & Bower (2001) MNRAS
Simulated Images of a cluster of galaxies(170 μm) Convolved image at z=1 Original cluster at z=1 Convolved image at z=2 Convolved image at z=3
Strategy • Search for overdensity regions in FIS data (~ a few arcminutes) • Followup observations with ground based telescope • Probably very efficient way of detecting high-z clusters
Other Korean Proposals: Star forming regions Supernova Remnants Interplanetary dust particles
Infrared Study of Star-Forming Regions in Our Galaxy • Starless Cores (+YSOs) [Low Mass Stars] • Ultra-Compact HII Regions and Their Precursors [High Mass Stars]
Starless Class 0 Class I Class II Class III
Purposes: - Are they really starless? Substellar objects with disks: IRC - SEDs from NIR to FIR of YSOs Better classification - Time scales in each phase - Any differences in density profile between starless cores and cores with star? FIS - Any relation between density profile and infall motion? Radio survey
Ultra-Compact HII Regions and Their Precursors - UC HII Regions: early phase of evolution of massive stars • Massive YSOs [hot cores, maser, sub-mm continuum, MIR] earlier than UC HII regions Precursors • Propose to do IR imaging of those objects and surroundings nature of ionizing stars, discovery of more precursors
UC HII Regions NIR & MIR photometry Radio continuum recombination lines + Radiative Transfer Model information on Lstar , Teff, rout, rin, etc. (Campbell et al. 2000)
NIR Imaging: Identification of ionizing stars - comparison bet. NIR & radio continuum images - K-L color (Walsh et al. 1999) Spectral type of ionizing stars - MIR & radio continuum data (Walsh et al. 2001) - stellar NIR spectra (Hanson et al. 2002)
Precursors of UC HII Regions Precursor Candidates: Maser sources (CH3OH, H2O) (sub)mm sources MIR sources MIR Imaging in Search for Precursors MIR sources without radio emission
Summary • ASTRO-F/FIS will provide a fundamental data base for forthcoming IR missions and other astrophysical research • Many projects are being planned • Korean participation: - Galaxy clusters - Complementary of SIRTF Survey for galaxy evolution - Star formation - Supernova remnants - Solar system objects