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Galaxy Morphology - Halo Gas Connections

Glenn G. Kacprzak·Christopher W. Churchill·Charles C. Steidel
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Abstract

We studied a sample of 38 intermediate redshift MgII absorption-selected galaxies using (1) Keck/HIRES and VLT/UVES quasar spectra to measure the halo gas kinematics from MgII absorption profiles and (2) HST/WFPC-2 images to study the absorbing galaxy morphologies. We have searched for correlations between quantified gas absorption properties, and host galaxy impact parameters, inclinations, position angles, and quantified morphological parameters. We report a 3.2-sigma correlation between asymmetric perturbations in the host galaxy morphology and the MgII absorption equivalent width. We suggest that this correlation may indicate a connection between past merging and/or interaction events in MgII absorption-selected galaxies and the velocity dispersion and quantity of gas surrounding these galaxies.

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Glenn G. Kacprzak, Christopher W. Churchill, Charles C. Steidel. 2005-05-10. Galaxy Morphology - Halo Gas Connections. https://doi.org/10.1017/s1743921305002474

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