Molecular Gas Excitation and Chemistry in Nearby LIRGs with ALMA

We present high resolution molecular line observations of dusty AGN and starburst in nearby luminous infrared galaxies (LIRGs), VV 114 and NGC 1614, with cycle 0 and 2 ALMA. We carried out a part of band 3 (84.5 - 108.5 GHz) line survey of VV 114 and preliminary detected rare species such as the SO, CH₃CCH, and HC₃N, as well as the strong HNC, C¹⁸O, ¹³CO, CN, and CS emission. These lines show different distributions from region to region in VV 114 (AGN/starburst/shocks), and the strengths are also different due to effects of the gas excitation and the gas-phase chemistry. For starburst-dominated galaxy NGC 1614, we detected multi-CO transitions, the CO (1-0), CO (2-1), CO (3-2), CO (6-5), ¹³CO (2-1), and C¹⁸O (2-1). All the transitions are detected in the nuclear starburst ring, while an extended disk component cannot be traced in the CO (6-5) and C¹⁸O (2-1). The excitation condition of the ring and the disk can be explained/modeled by the star formation rate surface densities traced in the Paschen alpha emission. Multi-molecule imaging help us to diagnose the chemical differences of ISM, while multi-transition imaging allow us to investigate gas physical conditions affected by nuclear activities directly.