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www.dark-cosmology.dk/~pela Lyman — The Great Escape Dark Cosmology Centre | Niels Bohr Institutet | Københavns Universitet DFS Annual Meeting 2009 Supervisors: Anja C. Andersen & Jesper Sommer-Larsen
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2 Ly escape from high-z galaxies Why? What? How? Ly is a powerful probe of the early Universe very
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3 Ly escape from high-z galaxies Why? What? How? Ly is a powerful probe of the early Universe very
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4 Ly escape from high-z galaxies Analytical attempt (Neufeld 1990) Gas density and temperature Dust density and cross-section
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5 Neufeld (1991); Hansen & Oh (2006) Multiphase medium? Ly escape from high-z galaxies – Why does Ly escape after all? Kunth et al. (1999); Verhamme et al. (2006); Östlin et al. (2008) Outflow? Tenori-Tagle et al. (1999); Mas-Hesse et al. (2003); Ionized holes? Kunth et al. (2003); Hayes et al. (2007)
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6 Numerical approach Cosmological N-body + hydro simulation + Ly RT on AMR grid with dust
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7 Dust Four important quantities: Density: n d Cross-section: d ( ) Albedo: A Phase function: P( )
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8 Dust Four important quantities: Density: n d Cross-section: d ( ) Albedo: A Phase function: P( )
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9 Dust Pei (1991) + Weingartner & Draine (2001) + Gnedin et al. (2008) Four important quantities: Density: n d Cross-section: d ( ) Albedo: A Phase function: P( )
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10 Dust Calzetti et al. (1995); Lillie et al. (1976); Li & Draine (2001) Four important quantities: Density: n d Cross-section: d ( ) Albedo: A Phase function: P( )
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11 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe
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12 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe Emit photon
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13 Emit photon Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe Propagate thru ISM
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14 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe Propagate thru ISM Interact with gas or dust Emit photon
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15 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe Interact with gas or dust New and ñ Propagate thru ISM Emit photon
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16 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe New and ñ Scatter/absorb Interact with gas or dust Propagate thru ISM Emit photon
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17 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe Scatter/absorbNew ñ New and ñ Interact with gas or dust Propagate thru ISM Emit photon
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18 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe ✞ Scatter/absorbNew ñ New and ñ Interact with gas or dust Propagate thru ISM Emit photon
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19 Monte Carlo In each cell: L Ly , T, v bulk, n HI, n HII, Z C,N,O,Mg,Si,S,Ca,Fe Escape ✞ Scatter/absorbNew ñ New and ñ Interact with gas or dust Propagate thru ISM Emit photon
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20 Results Surface brightness map
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21 Results Surface brightness profile
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22 Results Surface brightness profile: dust helps to make profile look more extended
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23 Results Spectrum
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24 Results f esc (M vir )
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25 Songaila (2004) IGM transmission z = 6.3 z = 5.7 z = 3.6
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26 IGM transmission
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27 IGM transmission z = 6.3 z = 5.7 z = 3.6
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28 Summary Many factors help facilitating the escape of Ly Spectrum affected in a highly non- grey fashion f esc decreases with increasing M vir Dust makes SB profile even more extended Problem can be inversed: Predict results of future observations (e.g. Ultra-VISTA) You cannot escape the raptor
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29 Summary Many factors help facilitating the escape of Ly Spectrum affected in a highly non- grey fashion f esc decreases with increasing M vir Dust makes SB profile even more extended Problem can be inversed: Predict results of future observations (e.g. Ultra-VISTA) You cannot escape the raptor
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30 Summary Many factors help facilitating the escape of Ly Spectrum affected in a highly non- grey fashion f esc decreases with increasing M vir Dust makes SB profile even more extended Problem can be inversed: Predict results of future observations (e.g. Ultra-VISTA) You cannot escape the raptor
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31 Summary Many factors help facilitating the escape of Ly Spectrum affected in a highly non- grey fashion f esc decreases with increasing M vir Dust makes SB profile even more extended Problem can be inversed: Predict results of future observations (e.g. Ultra-VISTA) You cannot escape the raptor
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32 Summary Many factors help facilitating the escape of Ly Spectrum affected in a highly non- grey fashion f esc decreases with increasing M vir Dust makes SB profile even more extended Problem can be inversed: Predict results of future observations (e.g. Ultra-VISTA) You cannot escape the raptor
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