Quantitative Evolution of Disk Galaxies

Bodo L. Ziegler

I’ll make the case for combining imaging and spectroscopic panoramic surveys by showcasing pilot projects based on hundreds of galaxies both in the field and in clusters out to redshifts 1.5. Over the last years we gathered large samples of distant disk galaxies with both HST imaging and high spectral resolution spectroscopy allowing the determination of accurate structural parameters and internal kinematics as well as stellar population parameters. Only the combination of all these important aspects enables us to constrain galaxy evolution on physical bases. Some of our results are: 1) half of 260 field galaxies show disturbed kinematics while the other half have ordered rotation,2) peculiar galaxies are compatible with disk growth via accretion, 3) the Tully-Fisher relation evolves mildly with a brightening of 1.2mag to z=1 in B-band for given Vmax, 4) sizes have grown by a factor 1.5 in the last 8 Gyrs, 5) the Dark Matter mass fraction hardly changes, 6) cluster galaxies with ongoing star formation have similar SF rates like field galaxies and follow the same TFR at intermediate redshifts (z=0.5), 7) emission-line rotating disks in early-stage (z=1.4) clusters have significant deviations in both directions in the TFR plane, 8) red spirals in low-z clusters show evidence for ram-pressure stripping. To put these findings on statistically solid grounds still larger samples are necessary encompassing all different galaxy types.