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Intergalactic transmission and its impact on the Lyman a line. Peter Laursen Potsdam, 2011. Oskar Klein Centre | Inst. för Astronomi | Stockholms Universitet. www.dark-cosmology.dk /~pela. Lyman a modeling. Theoretically Osterbrock (1962) Adams (1972) Harrington (1973)
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Intergalactic transmission and its impact on the Lyman a line Peter Laursen Potsdam, 2011 Oskar Klein Centre | Inst. för Astronomi | Stockholms Universitet www.dark-cosmology.dk/~pela
Lyman a modeling Theoretically Osterbrock (1962) Adams (1972) Harrington (1973) Neufeld (1990, 1991) Loeb & Rybicky (1999) Dijkstra+ (2006) Numerically Auer (1965) Avery & House (1968) Loeb & Rybicky (1999) Ahn et al. (2001, 2002) Zheng & Miralda-Escudé (2002) Cantalupo+ (2005) Dijkstra+ (2006) Hansen & Oh (2006) Tasitsiomi (2006) Verhamme+ (2006) Laursen+ (2007, 2009) Barnes+ (2010, 2011) Zheng+ (2010, 2011)
Standard approach • Ignore • Remove blue half • Reduce full line by some factor e–<t>
Numerical approach Cosmological N-body+hydro simulation (SPH, Sommer-Larsen et al. 2003, 2006) + ionizing UV RT (Razoumov & Sommer-Larsen 2006, 2007) + hi-res resimulations of interesting regions + galactic Monte Carlo Ly RT with dust + IGM RT
Galactic RT – MOCALATA* Each cell: nHI, nHII, T, vbulk, LLya, Zi ⇒nd * PL et al. 2009, ApJ, 696, 853 and 2009, ApJ, 704, 1640
Galactic RT – MOCALATA* No scattering With scattering Including dust * PL et al. 2009, ApJ, 696, 853 and 2009, ApJ, 704, 1640
Galactic RT – MOCALATA* * PL et al. 2009, ApJ, 696, 853 and 2009, ApJ, 704, 1640
Intergalactic RT – IGMTRANSFER* *PL et al. 2011, ApJ, 728, 52; the code can be downloaded fromwww.dark-cosmology.dk/~pela/IGMtransfer.html
Intergalactic RT – IGMTRANSFER* *PL et al. 2011, ApJ, 728, 52; the code can be downloaded fromwww.dark-cosmology.dk/~pela/IGMtransfer.html
Intergalactic RT – IGMTRANSFER* *PL et al. 2011, ApJ, 728, 52; the code can be downloaded fromwww.dark-cosmology.dk/~pela/IGMtransfer.html
Intergalactic RT – IGMTRANSFER* z = 3.5 *PL et al. 2011, ApJ, 728, 52; the code can be downloaded fromwww.dark-cosmology.dk/~pela/IGMtransfer.html
Intergalactic RT – IGMTRANSFER* z = 5.8 *PL et al. 2011, ApJ, 728, 52; the code can be downloaded fromwww.dark-cosmology.dk/~pela/IGMtransfer.html
Intergalactic RT – IGMTRANSFER* z = 6.5 *PL et al. 2011, ApJ, 728, 52; the code can be downloaded fromwww.dark-cosmology.dk/~pela/IGMtransfer.html
The origin of the dip Velocity field Density field
Impact on the Lya profile z = 3.5 Transmission function Observed spectrum Spectrum escaping galaxy
Impact on the Lya profile z = 3.5
Impact on the Lya profile z = 5.8
Impact on the Lya profile z = 6.5
Transmitted fraction z = 3.5
Transmitted fraction z = 5.8
Transmitted fraction z = 6.5
Alternative to outflow model? z = 3 – 4 ? Verhamme et al. 2008, A&A, 491, 89
Probing the very first galaxies z = 8.8 Ultra-VISTA PIs Jim Dunlop, Marijn Franx, Johan Fynbo, & Olivier LeFèvre
Probing the very first galaxies z = 8.8 Compare with Dijkstra & Wyithe 2010, MNRAS, 408, 352: ~5%
Probing the Epoch of Reionization Songaila 2004, ApJ, 127, 2598 43
Summary • • IGM absorption may explain at least some of the asymmetric Lyprofiles Reionization may have initiated earlier than probed by WMAP • Transmitted fractions are 0.77+17 at z = 3.5 –34 0.26+13 at z = 5.8 –18 0.20+12 at z = 6.5 –18 0.05+?? at z = 8.8 –??
Extra stuff With Hannes Jensen (OKC), Garrelt Mellema (OKC), Ilian Iliev (U. of Sussex), & Paul Shapiro (U. of Texas)