| Abstract |
Dissipative processes play a major role in controlling the growth of
galaxies, particularly in producing their dense baryon dominated central
regions. Observations exploring how baryons lose energy and angular
momentum to allow gas to flow into the centers of galaxies therefore
provide important windows into galaxy evolution. One such pathway is
associated with the presence of small, gas-rich disks. These features
can be especially prominent in lower mass starburst galaxies, where they
sometimes appear as remarkable miniature spirals. The compact starburst
galaxies NGC 3928 (MB = -18.6) and II Zw 168 (MB =
-21.4) are examples of this phenomenon, hosting high surface brightness
inner disks with diameters of approximately 3 kpc and 5 kpc,
respectively. Both disks display well developed spiral structure, and
are embedded in larger diffuse stellar envelopes. Using a combination of
data from the archives and our observations, we present basic physical
characteristics of these two systems, which include spiral arms with
widths of only 100 pc, and utilize this information to investigate
their unusual evolutionary states.
This research has been supported in part by grant NSF AST-0708967 and
made use of the WIYN Observatory 0.9-m and 3.5-m telescopes. |