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The CIV-MgII Kinematics Connection in ~0.7 Galaxies

C. W. Churchill·R. R. Mellon·J. C. Charlton·B. T. Jannuzi·S. Kirhakos·C. C. Steidel·D. P. Schneider
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Abstract

We have examined Faint Object Spectrograph data from the Hubble Space Telescope Archive for CIV 1548,1550 absorption associated with 40 MgII 2796,2803 absorption-selected galaxies at 0.4 < z < 1.4. We report a strong correlation between MgII kinematics, measured in 6 km/s resolution HIRES/Keck spectra, and W_r(1548); this implies a physical connection between the processes that produce "outlying velocity" MgII clouds and high ionization galactic/halo gas. We found no trend in ionization condition, W_r(1548)/W_r(2796), with galaxy-QSO line-of-sight separation for 13 systems with confirmed associated galaxies, suggesting no obvious ionization gradient with galactocentric distance in these higher redshift galaxies. We find tentative evidence (2-sigma) that W_r(1548)/W_r(2796) is anti-correlated with galaxy color; if further data corroborate this trend, in view of the strong CIV-MgII kinematics correlation, it could imply a connection between stellar populations, star formation episodes, and the kinematics and ionization conditions of halo gas at z~1.

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C. W. Churchill, R. R. Mellon, J. C. Charlton, B. T. Jannuzi, S. Kirhakos, C. C. Steidel, D. P. Schneider. 1999-04-21. The CIV-MgII Kinematics Connection in ~0.7 Galaxies. https://doi.org/10.1086/312102

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