Distant spheroids in the GOODS fields

To this end, bulges have been isolated for a sample of 137 spiral galaxies within the redshift range 0.1<z<1.2 in the GOODS fields. Using proven photometric techniques, we determine the characteristic parameters (size, surface brightness, profile shape) of both the disk and bulge components in our sample.

In agreement with earlier work that utilized aperture colors, distant bulges show a broader range of optical colors than would be the case for passively evolving populations. To quantify the amount of recent star formation necessary to explain this result, we used DEIMOS to secure stellar velocity dispersions for a sizeable fraction of our sample. This has enabled us to compare the fundamental plane of our distant bulges with that for spheroidal galaxies in a similar redshift range.