Galaxy Properties and the Kinematics of Gaseous Halos Chris Churchill (NMSU) Glenn Kacprzak (NMSU) Chuck Steidel (Caltech) also see: Poster (G. Kacprzak;Thursday)

In 4 of 5 galaxies, the extended halo kinematics “knowns” about the stellar kinematics in the visible galaxy… Consistent with “lagging halo” scenarios What Are the Kinematic Relationships? Are the kinematics of the extended gas surrounding intermediate redshift galaxies coupled to the galaxy kinematics? What are the relationships between galaxy morphologies and sightline orientations and the kinematics of extended gaseous envelopes? What are the implications for galaxy evolution in the epoch of “passive” galaxy evolution (z<1)? Steidel etal (2002)

Morphologies and Orientations QSO

Orientation and Kinematics… Premise: equivalent width is strong measure of number of clouds probed by sightline and moderate measure of kinematic spread of absorbing gas Quantifying sightline orientation: position angle and inclination Prediction: Equivalent width correlated with cos(PA)cos(i)

There is NO correlation between absorption strength and the combined quantity of position angle and inclination. cos(PA)cos(i) vs. Equivalent Width Orientation and Kinematics…

Morphology and Kinematics… Modeling galaxies using GIM2D (Simard 2002) Measured morphological perturbations and asymmetries HST image Model image Residual image

There is a 2.8  correlation between absorption strength and galaxy morphological perturbations, i.e., asymmetry. 3R 1/2 vs. Equivalent Width Morphology and Kinematics… pathological morphological perturbations normal R 1/2 = 5%

Galaxies and Weak Systems… z<1.4 Churchill etal (1999) z>1.4 CWC, W.L.W. Sargent, M. Rauch, & M. Murphy (in prep) Some weak systems (W 20 kpc. In z=0.668 galaxy, absorption precisely at the galaxy’s systemic velocity Some weak systems arise in virialized halos,  >100, not in filaments, sheets, or voids. NEW RESULT: Weak systems appear to evolve away at higher redshifts, where UVB photon emissivity is high… consistent with evolution of Ly  clouds evolution at z=1.7 (same  also see: Poster (R. Lynch;Thursday)

Conclusions and Future Work … Are the kinematics of the extended gas surrounding intermediate redshift galaxies coupled to the galaxy kinematics? YES. But sample size is small (5 galaxies). Also, 1 counter example… Need rotation curves for 25 additional galaxies in our sample. Gemini and Keck. Compare with local 21-cm emission and DIGs measurements of lagging halos, beards, and forbidden gas. What are the relationships between galaxy morphologies and sightline orientations and the kinematics of extended gaseous envelopes? Orientation and Equivalent Width: NO correlation Morphology and Equivalent Width: YES correlation (2.8 s) with pathology. Need to directly quantify kinematics from HIRES/Keck data; have in hand 20 for the 25 galaxies. Use VP profile fitting, etc. Need five more HIRES/Keck spectra.