论文标题
对高富度弥漫星系的CO观测
CO observations toward HI-rich Ultra Diffuse Galaxies
论文作者
论文摘要
我们提出了与IRAM 30-m望远镜在处女座群集中的六个高富度超湿星系（UDG）以及一个UDG（VLSB-A）样品的样品。 CO 1-0在AGC122966中在4sigma水平上略有检测，是对UDGS中CO发射的首次检测。我们从非检测的CO系中估算了其他星系中分子质量的上限。这些上限和AGC122966中的边缘CO检测表明分子和原子气体质量之间的质量比低。随着恒星形成效率从分子气中得出，我们建议在这种高富集的UDG中恒星形成效率低，这可能是由于从原子气转化分子的效率低而导致的，而不是从分子气中形成恒星的效率低。
We present CO observations toward a sample of six HI-rich Ultra-diffuse galaxies (UDGs) as well as one UDG (VLSB-A) in the Virgo Cluster with the IRAM 30-m telescope. CO 1-0 is marginally detected at 4sigma level in AGC122966, as the first detection of CO emission in UDGs. We estimate upper limits of molecular mass in other galaxies from the non-detection of CO lines. These upper limits and the marginal CO detection in AGC122966 indicate low mass ratios between molecular and atomic gas masses. With the star formation efficiency derived from the molecular gas, we suggest that the inefficiency of star formation in such HI-rich UDGs is likely caused by the low efficiency in converting molecules from atomic gas, instead of low efficiency in forming stars from molecular gas.
