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Jesper Sommer-Larsen Dark Cosmology Centre, Niels Bohr Institute, Copenhagen Where are the "Missing" GalacticBaryons ?, The z~1 TF relation, Baryon “pinching” of DM haloes, Young Galaxies in Ly-alpha
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Collaborators on the projects: Laura Portinari, Tuorla, Finland Jesper Rasmussen, Birmingham, UK Kristian Pedersen, Dark, Copenhagen Sune Toft, ESO Kim Nilsson, ESO Johan Fynbo, Dark, Copenhagen Palle Moeller, ESO Peter Laursen, Dark, Copenhagen Richard Bower, Durham, UK Andrew Benson, Oxford, UK Malcolm Fairbairn, Stockholm, Sweden Michael Gustafsson, Stockholm, Sweden
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The missing baryons problems 1) Omega_b = /rho_crit = 0.04-0.045. Observed in the Ly-alpha forest at z~2-4, but Omega_* ~ 0.003 at z~0 !! 2) f_b ~ 0.15 Milky Way: M_vir ~ 8 x 10^11 Msun, so M_* ~ 1.2 x 10^11 Msun, but M_* ~ 6-7 x 10^10 Msun !!
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Growth of (Dark Matter) Density Fluctuations by Gravitational Instability in an expanding Universe
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The Cosmic Microwave Background
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Cosmological Dark Matter Simulation at z=0
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First detection of extended, soft (T~0.4 keV) X-ray emission from the halo of a quiescent disk galaxy (V_c=307 km/s) Pedersen et al., New Astronomy, 11, 465 (2006)
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NGC5746: Theory versus Observations
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”External” baryon fractions Sommer-Larsen (2006), ApJL, 644, L1
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”External” baryon fractions Dependence on feedback physics
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Disk+bulge, Hot gas, and Virial Masses versus characteristic circular speed
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Contribution of baronic galaxy mass using the Gonzalez et al. (2000) velocity function
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Warm (T~10^4 K) halo clouds ”High Velocity Clouds” pppppppppppp (Putman & Sommer-Larsen 2006) p pppp Temperature: Density:
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Mass distribution of warm halo clouds (”High Velocity Clouds”)
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The I-band z=0 Tully-Fisher relation Portinari & Sommer-Larsen (2006, astro-ph/0606531)
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The stellar mass z=0 TF relation Portinari & Sommer-Larsen (2006, astro-ph/0606531)
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Contribution of baryons to total v_c(R) using Pizagno et al. (2005) observations of ~bulgeless disk galaxies
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Evolution of the B-band TF relation from z=1 to 0 Portinari & SL (2006)
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Evolution of the stellar mass TF from z=1 to 0 Portinari & SL (2006)
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Baryonic ”pinching” of the (cold) dark matter haloes of …..………...two Milky Way like disk galaxies Gustafsson, Fairbairn & SL (2006) V_c=245 km/s V_c=233 km/s
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Orbital structure of dark matter haloes = A * x^w, x = r/r_vir ”Adiabatic” contraction parameters (A,w) = (1,1) Blumenthal et al. (1986) (A,w) ~ (0.8,0.8) Gnedin et al. (2004)
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”Adiabatic” contraction Reconstruction Gustafsson, Fairbairn & SL (2006) V_c = 233 km/s
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Determination of the (A,w) parameters Gustafsson, Fairbairn & SL (2006) V_c = 233 km/s
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Detection of gamma-rays from DM annihilation Gustafsson, Fairbairn & SL (2006)
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www.dark-cosmology.dk DARK Cosmology Centre | Niels Bohr Institutet | Københavns Universitet Laursen & Sommer-Larsen (2006) Ly Resonant Scattering in Young Galaxies
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Observational data from J. Fynbo Simulation data from J. Sommer- Larsen Motivation
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Basis Interpolation onto grid Data from J. Sommer-Larsen et al. Lyman-alpha resonant scattering RT by a Monte-Carlo approach Tasitsiomi (2006) Cantalupo et al. (2006) Dijkstra & Haiman (2006)
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No scattering; yz -plane Imaging Results
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Imaging Scattering; yz - plane
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Results Imaging Scattering; xy - plane
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