Poster Presentation

Starbursting molecular clouds in gas-rich merging galaxies

Author(s): Toshiki Saito (Shizuoka University) and the PHANGS-ALMA team

Presenter: Toshiki Saito (Shizuoka University)

(U)LIRGs form stars 10-100 times more efficiently than main sequence galaxies, which is explained by nearby (U)LIRGs being gas-rich merging galaxies. Numerical simulations and sub-kpc observations clearly show that tidal interaction between gas-rich progenitors is condensing gas and triggering subsequent starburst activity in the nuclear region and throughout the extended disk. However, it remains unclear if the properties of their molecular clouds, as the sites for star formation, themselves differ as well from those in normally star-forming galaxies. Obvious differences would potentially imply important changes to current theories. Before ALMA it was impossible to study clouds in (U)LIRGs. We present <150 pc resolution CO(2-1) data for 33 nearby (U)LIRGs and compare basic statistical cloud properties between nearby (U)LIRGs and nearby main sequence galaxies from the PHANGS-ALMA large program.