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Science with continuum data

Science with continuum data. ALMA continuum observations: Physical, chemical properties and evolution of dust, SFR, SED, circumstellar discs, accretion discs. Abundance+composition of dust affect the galaxies’ spectral appearance & influence the physical properties (SFR,

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Science with continuum data

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  1. Science with continuum data ALMA continuum observations: Physical, chemical properties and evolution of dust, SFR, SED, circumstellar discs, accretion discs

  2. Abundance+composition of dust affect the galaxies’ spectral appearance & influence the physical properties (SFR, metallicity,E(B-V)) Effects of dust Intensity Devriendt et al. 99 Wavelength

  3. SED evolution: SFR, reprocessing dust Tburst=2 Gyr Tburst=0.5 Gyr

  4. The evolution of a galaxy SED attenuated stellar spectrum HII regions: SN as origin of dust reradiated dust emission HI regions: later AGB Contribution dust production delayed by a few 108 yr Dwek 2005

  5. The evolution of dust with metallicity separate contribution from AGB stars to silicate and carbon dust Dwek 2005

  6. K-correction Sensitivity with 6 antennas Flux stays constant Griffin, 05 Blain, 04

  7. The covering factor of dust in AGNs from the SED dust covering factorY IR-bump Blue-bump local AGN 0 X-ray IR Opt.-UV log n F(n) -2 12 14 16 18 20 Log n The FIR measures the IR bump of high-z QSO and Seyfert -> evolution of dust covering factor and obcuration at high-z

  8. SEDs of QSOs and RGs ISO+MAMBO+ SCUBA SEDs reflect dust distribution around the heating source + nature of the heating source Haas et al., 2005

  9. Protostar development The continuum evolves as the star evolves

  10. IRAS 05358+3543 High mass star forming regions Protobinary system at projected separation of 1700AU • ALMA will resolve continuum emission on ~100AU scales in high-mass (50-100 M) star forming regions • - are there accretion disks in massive protostars and how do they look like? • - to which extent are massive protostellar core fragmented/clustered? • - how does high-mass star formation proceed? • coalescence of lower mass objects requires extremely dense clustering • via disk accretion as is the case for low mass star formation? • it seems well documented observationally that the disk accretion scenario plays a major role at least for moderately massive protostars (10-20M).These are rare, distant, and clustered star formation adds to make them difficult to observe with current facilities. multiple molecular outflows?

  11. SED changes with grain chemical and physical properties

  12. Dust emissivity depends on chemestry and grain size • Grain Radius Relation b = Qpr/(a) ,a: grain density and radius, Qpr radiation pressure Amorphous Carbon Amorphous Silicates Graphite poor Graphite rich Crystal. Silicates Log[b] Models run Log[a(mm)]

  13. Small grains Intermediate grains Large grains C400 C1000 SEDs depend on chemical composition MgFeSiO4 SED of a dust disk generated by an outer belt of planetesimals with inner planets is fundamentally different from that of the disk without planets. Mg0.6Fe0.4SiO3 Mg 1.9Fe 0.1SiO4 MgSiO3 SingleGrain Size, Single Composition Disk SED

  14. dust emission from a face-on disc with a planet ALMA 900GHz simulations Integration time 8 hours; 10 km baselines; 30 degrees phase noise 1 Mjup 0.5 M 5 MJup 2.5 M Detection of the warm dust in the vicinity of the planet only for distance 50-100pc orbital radius 5 AU distance 50pc, total disc mass 10-2 M Combined beam orbital radius 5 AU distance 100pc, total disc mass 10-2 M Disc + planet (Wolf & D’Angelo 2005)

  15. SED of dust discs in presence of different planetary configurations, 4 grain chemestry same particle size distribution n(b)db=n0b-q, distance 50pc, total mass 10-10 M Final Disk SED

  16. The SED is very sensitive to inclination Four geometries, ten inclinations Pole-onedge-on ice silicate [From Van Dishoeck , ARAA 2004] Silicate feature depends on grain properties and disc geometry [Whitney et al. 2004]

  17. Dust Cycling in GalaxiesGlobal cycle and interstellar processing Diffuse ISM a few 107 yrs Molecular Clouds • CNM • WNM • WIM • cloud envelopes • dense cores Low mass stars Giants Star Formation 3 109 yrs 109 yrs SN 3 106 yrs Massive stars

  18. Dust Spectral Energy DistributionEvidence for dust evolution=> From the diffuse ISM to molecular clouds, PAHs to large grains • Comp. Power Mass • PAH 18% 6% • VSG 15% 6% • BG 67% 88% Cold dust associated with dense molecular gas: lower temperature, larger far-IR emissivity, no small grains Enhanced VSG abundance in low density gas (the Spica HII region) Variations in PAH abundance in the diffuse ISM and PDRs

  19. Dust SED/Composition Dust in the Spica HII region => Enhanced VSG abundance factor ~ 5 : shock processing?

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