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A. Leroy, A. D. Bolatto, J. D. Simon, L. Blitz (U. C. Berkeley), F. P. Israel (Sterrewacht Leiden)
We present the initial results of a millimeter--submillimeter survey of nearby dwarf galaxies. Using the BIMA array, we have obtained high--resolution CO (1arrow0) observations of most nearby dwarf galaxies with known CO emission. These data are combined with submillimeter CO and continuum observations obtained at the JCMT. A goal of this survey is to characterize the behaviour of the CO emission and the dust continuum with metallicity. To achieve this purpose, we use the BIMA maps and the submillimeter continuum observations to obtain cloud masses, and the submillimeter line data to constrain the CO excitation. Because small systems such as dwarf galaxies are the first to form in the currently favored bottom--up cosmological scenarios, we expect that these data will help us understand the results of future millimeter/submillimeter surveys of the high--redshift universe. They will also permit us to study the problems of molecular cloud and star formation in systems that are dynamically much simpler than our own. Finally, for those sources that have enough molecular gas to properly sample galaxy kinematics near their centers, our interferometric CO data yields a rotation curve determination with a spatial resolution difficult to attain by HI observations. We have used these rotation curves to study the central density profiles of the low--mass dark matter halos. To locate other CO emitting dwarf galaxies suitable for this type of high--resolution study we have undertaken a single--dish CO survey, including all nearby northern dwarf galaxies detected by IRAS, currently partially completed using the UASO Kitt Peak 12 m telescope. This portion of the survey has achieved a ~ 30% detection rate, finding CO emission in 14 new sources.