Molecular gas and the nuclear star cluster in IC 342:: Sufficient inflow for recurring star formation events?

被引:37
作者
Schinnerer, E
Böker, T
Meier, DS
机构
[1] Natl Radio Astron Observ, Socorro, NM 87801 USA
[2] Space Telescope Sci Inst, Baltimore, MD 21218 USA
[3] Univ Illinois, Urbana, IL 61801 USA
关键词
galaxies : individual (IC 342); galaxies : ISM; galaxies : kinematics and dynamics; galaxies : nuclei;
D O I
10.1086/377118
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present high spatial resolution (1."2) millimeter-interferometric observations of the (CO)-C-12 (2 -1) line emission in the central 300 pc of the late-type spiral galaxy IC 342. The data, obtained with the Owens Valley Radio Observatory, allow first-time detection of a molecular gas disk that coincides with the luminous young stellar cluster in the nucleus of IC 342. The nuclear CO disk has a diameter of similar to 30 pc and a molecular gas mass of. M-H2 similar to 2 x 10(5) M-. It connects via two faint CO bridges to the well-known 100 pc diameter circumnuclear gas ring. Analysis of the gas kinematics shows that the line of nodes in the inner 15 pc is offset by about 45degrees from the major kinematic axis, indicating noncircular motion of the gas within a few parsecs of the dynamical center of IC 342. Both the morphology and the kinematics of the CO gas indicate ongoing inflow of molecular gas into the central few parsecs of IC 342. We infer a gas inflow rate between 0.003 and 0.14 M-., yr(-1), based on the observed surface density of the nuclear gas disk and estimates of the radial velocities of the surrounding gas. Inflow rates of this order can support repetitive star formation events in the nucleus of IC 342 on timescales much smaller than a Hubble time.
引用
收藏
页码:L115 / L118
页数:4
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