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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Extra-planar gas at low and high redshifts Filippo Fraternali Department of Astronomy, University of Bologna, Italy Filippo Fraternali Department of Astronomy, University of Bologna, Italy
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Extra-planar gas now and then Gaseous halos in edge-on galaxies and in galaxies at intermediate inclinations Are they observable at high-z? Star Formation and Gas Accretion History
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Extra-planar gas in edge-on galaxies
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z NGC 891: HI observations Total Mass of the HI halo M HI ~1.2 x 10 9 M ~30% M HItot > 200 hrs with the WSRT Sancisi et al. 2008, A&ARv Oosterloo, Fraternali, Sancisi 2007
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Artificial data-cubes NGC 891 and models HI Channel maps Thin disk Halo gas V Sys
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Models with lagging halo NGC 891 and models HI Channel maps Thin disk Halo gas V Sys
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z NGC891 at high redshifts z = 0.5 Spatial resolution (seeing) 0.6 ~ 3.6 kpc Spectral resolution ( ) ~ 10 km s -1 No SB/flux corretion 1.5<z<2.5 Spatial resolution (seeing) 0.6 ~ 5 kpc Spectral resolution ( ) ~ 40 km s -1 No SB/flux corretion (VLT - FLAMES, O [II] ) (VLT - SINFONI, H )
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z NGC891 at high redshift z = 0.5 - FLAMES Local z = 2 - SINFONI
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Data cubes z = 0.5 - FLAMES z = 2 - SINFONI Halo features observable at high-z
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Rotation curves of edge-ons To observer Line of nodes V sys V ROT Line profile
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Rotational Gradient Fraternali et al. 2005, ASPC v rot ~15 km s -1 kpc -1 NGC 891 Strong rotational gradient with z
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Recovering rotation curves z = 0.5 - FLAMES z = 2 - SINFONI Disk rotation curve Original data High-z At 5 kpc above the plane Kinematics can be studied at high z!
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Extra-planar gas in inclined galaxies OpticalNeutral gas (VLA) Same scale! Fraternali et al. 2002, ApJ
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z NGC 2403: halo gas Halo gas 150 km/s Fraternali, Oosterloo, Sancisi & van Moorsel 2001 Halo gas Total Mass of the HI halo M HI ~3 x 10 8 M ~10% M HItot
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Data cubes Beards are difficult to observe at high-z z = 2 - SINFONI z = 0.5 - FLAMES
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Velocity fields z = 0.5 - FLAMES z = 2 - SINFONI
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Recovering N2403 rotation curve z = 0.5 - FLAMES z = 2 - SINFONI
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Velocity dispersion fields z = 0.5 - FLAMES z = 2 - SINFONI Only resolution effects!
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Gas accretion history
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Star formation history Hippelein et al. 2003 Panter et al. 2006 Cignoni et al. 2008 SFH in the Milky Way
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Gas accretion history Keres et al. 2005 It should follow SFR Cold or prone to cool Some other observable effect?
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Accretion: high velocity gas NGC891 Filament Counter-rotating clouds 580 km/s Energy needed 10 54-55 erg 15 kpc Forbidden in a fountain Accretion ~ 2 x 10 7 M /10 8 yr ~ 0.2 M yr -1
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Accretion: High Velocity Clouds Wakker 2007; Wakker & Van Woerden 1997; Tripp et al. 2003 Low metallicity Z=0.15 solar Low metallicity Z=0.1-0.4 solar HVCs masses ~< 10 7 M accretion rate ~ 0.2 M /yr Most of the accretion is hidden
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Minor mergers? Global accretion rates ~ 0.2 M O /yr Detected in ~25% of galaxies Masses ~ 1-10 x 10 8 M O Life time ~ 1-2 dyn time Sancisi et al. 2008, A&ARv Most of the accretion is hidden
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Gas dynamics in a pure fountain Fountain gas has too high angular momentum Fraternali & Binney, 2006, 2008 See also Heald et al. 2007
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Fountain + Accretion in NGC891 Best-fit Accretion Rate ~ 3 M o yr -1 Compare to SFR ~ 4 M o yr -1 NGC891 Halo gas: ~90% from fountain ~10% accreted Fountain must sweep up ambient gas at the rate ~ SFR
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Filippo Fraternali (Bologna University)3D - Munich - 12/06/08 Extra-planar gas at low and high z Conclusions 2. Halos in edge-on galaxies can be studied at high-z, beards not clear 3. Gaseous halos are the key to study gas accretion 1. Local galaxies are surrounded by massive gaseous haloes with complex structure
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