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Extended Halo Gas and Galaxy Kinematics At Intermediate Redshift. Glenn G. Kacprzak (NMSU / Swinburne). C. Churchill (NMSU) D. Ceverino (NMSU) A. Klypin (NMSU) C. Steidel (Caltech) M. Murphy (Swinburne) N. Vogt (NMSU). May 16 th 2008 Socorro, NM. Rots et al. 1990.
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Extended Halo Gas and Galaxy Kinematics At Intermediate Redshift Glenn G. Kacprzak (NMSU / Swinburne) C. Churchill (NMSU) D. Ceverino (NMSU) A. Klypin (NMSU) C. Steidel (Caltech) M. Murphy (Swinburne) N. Vogt (NMSU) May 16th 2008 Socorro, NM Rots et al. 1990
Some Key Questions… • How far in galactocentric distance does the kinematics of the gas couple to the angular momentum of the galaxy? • How well does the kinematics of the gas reflect the kinematics of the stellar galaxy? • Where is the galaxy halo-IGM interface? • Do we see dominate inflow and/or outflow signatures? • How important are stellar feedback energetics in regulating the sizes, geometries, dynamics, and multiphase ionization structures of galaxy halos? This Talk: • Results from the kinematic comparison of MgII absorption selected galaxies to their halo gas (0.3<z<1.0). • A similar preliminary kinematic study of galaxy/halo gas in cosmological simulations (as discussed by Ceverino and Churchill).
Galaxy/Halo Gas Kinematics For MgII Absorption Selected Galaxies Sample: 5 edge-on MgII absorption selected galaxies 4 of the 5 showed the trend for the halo gas kinematics follows that of the galaxies Halo gas rotation appears to dominate over infall and outflow What is needed is a larger sample which represents a broad range of orientations with respect to the quasar line of sight Steidel et al. (2002)
10 Galaxy Spectra Obtained on Keck ESI 5” z = 0.483 5” z = 0.313 z = 0.313 z = 0.328 z = 0.417 z = 0.852 z = 0.787 z = 0.494 z = 1.017 • Only 6 edge-on galaxies have been observed up until now. The results hint that the halo gas co-rotates with the galaxy. • Our goal is to explore different galaxy orientations with respect to the quasar line of sight as well as a full range of impact parameters.
10 Galaxy Rotation Curves Obtained with Keck/ESI Q0229+131 zgal= 0.4167 D= 38 kpc Fig 4. Same as Fig 3. Note again the alignment of the rotation curve and MgII absorption.
10 Galaxy Rotation Curves Obtained with Keck/ESI Q0454-220 zgal= 0.48382 D= 107 kpc Dlos (kpc) Flux Velocity (km/s) • In all but one case, all the extended absorbing gas resides on one side of the systemic velocity of the galaxy. • However, the a lagging halo model cannot reproduce the observed velocity spread in the gas. Gas velocities at 107 kpc are consistent with that of the galaxy Kacprzak et al. 2008b, in prep
Possible Orientation Effect? i < 50 (face-on) i > 50 (edge-on) Kacprzak et al. in prep
Mock QSO Spectra 170 kpc
Multiple Complex Mechanisms Contributing to halo Kinematics! Filament Inflow Consistent with Disk-like Kinematics Inconsistent with Disk-like Kinematics Outflow Via Winds & SN Planar Filament Inflow Foreground Satellites Dlos (kpc)
Galaxy Inclination Effects in MgII Absorption Edge-on Absorption Velocity offset (km/s) i=45 Face-on Absorption Velocity offset (km/s)
Mock QSO Spectra 170 kpc
3D View of Absorbing Gas Cells N(MgII) > 12
3D View of Absorbing Gas Cells N(MgII) > 12 N(CIV) > 12
3D View of Absorbing Gas Cells N(MgII) > 12 N(CIV) > 12 N(OIV) > 12
Velocity Distribution of Gas Cells MgII is primarily infalling material with a small fraction of has zero radial velocity. CIV and OVI peak exhibit lower velocity inflow. MgII and CIV/OVI are probing different structures and kinematic driving mechanisms in the halo N(MgII) > 12 N(CIV) > 12 N(OIV) > 12 Normalized # Radial Vel (km/s)
Halo Gas Kinematics LOS 1 N(MgII) > 12 N(CIV) > 12 N(OIV) > 12 LOS 1
In Conclusion • Kinematics: • Halo gas is almost always to one side of the systemic velocity of the galaxy. • The halo gas appears to be kinematically coupled to the galaxy, however, disk-like halo rotation models do not adequately reproduce the absorption velocities. • Simulations indicate that multiple energetic mechanisms give rise to the observed halo gas kinematics. • Simulations show that MgII gas arises in clouds and streams of infalling and outflowing material generated by minor mergers and satellite harassment. • Possible galaxy orientation effects seen in MgII absorption • CIV and OVI are more diffuse in the halo, different probes of energetics.