Most previous kinematical studies [\protect\astronciteForbes et al.1995][\protect\astronciteKoo et al.1995][\protect\astronciteColless1994][\protect\astronciteVogt et al.1993][\protect\astronciteFranx1993] have either suffered from small samples or the lack of spatial information, but they have shown that current telescopes can tackle the task of measuring the internal kinematics of intermediate redshift galaxies. In cases where spatial information was available, galaxies were typically at low redshifts and had relatively large intrinsic sizes.
Two studies had spatial information. Franx franx93 used the Multiple-Mirror Telescope (MMT) to measure the rotation curve of an E+A galaxy in Abell 665 at z = 0.18. The galaxy had an exponential disk scale length of 6.5 h kpc, and its circular velocity was estimated at 270 km/s. The galaxy was offset by 2.2 mag from the Faber-Jackson relation and by 0.3 mag from the Tully-Fisher relation. Vogt et al. vogt93 used the Hale 5-m telescope to observe the [OII] doublet (3726,3729) and the [OIII] line pair (4959,5007) in four galaxies at redshifts between 0.20 and 0.38. These galaxies were large intrinsically and had unusually strong [OII] emission. Two galaxies had [OII] emission concentrated in the nucleus. The other two galaxies had rotation velocities of 166 and 253 km/s which corresponded to offsets from the Tully-Fisher relation of 3.1 and 0.9 mag respectively.
Colless coll94 observed 54 galaxies with the Autofib fibre spectrograph on the AAT. The galaxies had redshifts in the range 0.150.35, [OII] equivalent widths > 20 Å, colors < 1.2 and magnitude in the range 21.2522.0. Twenty-four galaxies had detectable [OII] emission. Of the 24 detections, 9 had < 70 km/s and 15 had in the range 70200 km/s (11 had > 100 km/s). The preliminary conclusion of this work was that although some galaxies at z = 0.150.35 may be dwarfs, the majority had velocities typical of normal present-day galaxies.
Koo et al. koo95 measured line widths in a sample of 17 galaxies at z 0.10.7 with the Keck telescope. Twelve of these galaxies were compact (stellar-like), narrow emission line galaxies (CNELGSs), and five were more extended objects with colors and emission lines similar to CNELGSs. The galaxies were all luminous with M 21. Measured velocity widths were between 28 and 157 km/s instead of 200 km/s expected for nearby spiral galaxies of similar luminosity. Objects with < 65 km/s followed the same correlations between and both blue and H luminosities as those of nearby HII galaxies [\protect\astronciteTelles and Terlevich1993].
Forbes et al. forbes95 measured velocity line widths in 18 faint field galaxies with 19 < I < 22 and 0.2 < z < 0.4. Their sample showed a brightening of 1 mag in the luminosity-disk size and luminosity-internal velocity relations. However, their determination of brightening in the luminosity-internal velocity relation appears to have been measured with respect to the Rubin et al. rubin85 relations. The slopes of these relations are incorrect as shown in Figure , and lead to an underestimate of the luminosity brightening.
A recent internal kinematics study [\protect\astronciteVogt et al.1996] presented a beautiful set of rotation curves for nine faint field galaxies in the redshift range 0.1 z 1 observed with the Keck Telescope. The rotation curves appeared similar to those of local galaxies in both form and amplitude. The galaxies in this Keck sample were all brighter than M = 20.7 except for two galaxies with M = 19.3 and M = 19.8. Their sample therefore was a full magnitude brighter in absolute magnitude than the CFHT sample presented in Section . Owing to limited spatial resolution, the galaxies in the Keck sample were intrinsically big. Their disk scale lengths were all greater than 3.0 kpc except for one galaxy with a scale length of 1.8 kpc. These intrinsic sizes were much larger than the typical size of the objects studied in this thesis. Clearly, the two samples occupy different niches, and this has very interesting consequences as discussed in Section . The Keck study showed that at least some massive disks were in place at z 1. The kinematics of the Keck galaxies showed evidence for only a modest increase in luminosity (M 0.6 mag) compared to the local Tully-Fisher relation of Pierce and Tully pierce92. This is not surprising considering that all the galaxies are bright and massive. One would not expect to see any brightening in these galaxies based on a luminosity-dependent luminosity evolution scenario. This issue is further discussed in Section .