Tracing star formation in galaxies with molecular line and continuum observations

We report our recent progress on extragalactic spectroscopic and continuum observations, including HCN( J=1 –0), HCO + ( J=1 –0), and CN( N=1 –0) imaging surveys of local Seyfert and starburst galaxies using the Nobeyama Millimeter Array, high- J CO observations ( J=3 –2 observations using the Atacama Submillimeter Telescope Experiment (ASTE) and J=2 –1 observations with the Submillimeter Array) of galaxies, and λ 1.1 mm continuum observations of high- z violent starburst galaxies using the bolometer camera AzTEC mounted on ASTE.