Luminous Infrared Galaxies with the Submillimeter Array. I. Survey Overview and the Central Gas to Dust Ratio

We present new data obtained with the Submillimeter Array for a sample of 14 nearby luminous and ultraluminous infrared galaxies. The galaxies were selected to have distances DL < 200 Mpc and far-infrared luminosities log LFIR > 11.4. The galaxies were observed with spatial resolutions of order 1 kpc in the CO J = 3–2, CO J = 2–1,13CO J = 2–1, and HCO+ J = 4–3 lines as well as the continuum at 880 μm and 1.3 mm. We have combined our CO and continuum data to measure an average gas-to-dust mass …