Poster Presentation

CO multi-line observations toward the central region of barred spiral galaxy NGC613

Author(s): Keisuke Sato(The University of Tsukuba (1)),Yusuke Miyamoto(NAOJ),Nario Kuno(1),Dragan Salak(1),Alex Wagner(1),Masumichi Seta(Kwansei Gakuin University(2)),Naomasa Nakai(2)

Presenter: Keisuke Sato (The University of Tsukuba)

The central region (~ 1kpc) of the nearby Seyfert galaxy NGC613 is mainly divided into star-forming ring and circumnuclear disk. Near-infrared observations showed seven high star forming regions (hot spots) in the ring. Through high angular resolution observations in CO multi-line (12CO(1-0), 12CO(3-2) and 13CO(1-0)) with ALMA, we investigated the physical properties of molecular gas in the ring on GMC scale. The 12CO(1-0) PV diagrams revealed a difference in gas kinematics between the east and west side of the ring, suggesting a velocity jump at the south-west region, which can cause the lower star formation activity on the western side than the eastern side. Applying the size of the clouds identified by dendrogram to non-LTE radiative transfer analysis via RADEX, we estimated the temperature and density of the gas at each spot of the ring and bar. As a result, an increase in density from the bar to the ring was found, which supports sequential star formation along the ring (Pearls on a string scenario).