Ultra-High-Density Molecular Core and Warped Nuclear Disk in the Deep Potential of Radio Lobe Galaxy NGC 3079
Ultra-High-Density Molecular Core and Warped Nuclear Disk in the Deep Potential of Radio Lobe Galaxy NGC 3079
复制标题
射电瓣星系NGC 3079深处的超高密度分子核心和扭曲核盘
DOI：
10.1086/318907
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
J. Irwin
中科院分区：
文献类型：
--
作者：
Y. Sofue;J. Koda;K. Kohno;S. Okumura;M. Honma;A. Kawamura;J. Irwin
利用野边山射电天文台的一台由45 m望远镜和六元天线阵组成的七元毫米波干涉仪，对射电瓣边旋星系NGC 3079的12 CO（J = 1-0）线辐射进行了高分辨率的综合观测。发现半径为750 pc的核分子盘（NMD）与光盘成20°角，并具有旋臂。一个超高密度的核心（UHC）的分子气体被发现在核。在125 pc半径范围内，UHC的气体质量高达~3 × 108 M，比银河系中心相同区域的质量大一个数量级，平均密度高达~3 × 103 H2 cm-3。沿着长轴的位置-速度图沿着表明，旋转曲线已经开始在一个有限的速度超过300公里s-1从核。中心区域的表面质量密度估计高达~105 M <$pc-2，产生了非常深的引力势。我们认为，非常大的差异旋转在这样一个深的潜力将保持UHC引力稳定在当前的星星形成。
We have performed high-resolution synthesis observations of the 12CO (J = 1-0) line emission from the radio lobe edge-on spiral galaxy NGC 3079 using a seven-element millimeter-wave interferometer at the Nobeyama Radio Observatory, which consisted of the 45 m telescope and six-element array. The nuclear molecular disk (NMD) of 750 pc radius is found to be inclined by 20° from the optical disk, and the NMD has spiral arms. An ultra-high-density core (UHC) of molecular gas was found at the nucleus. The gaseous mass of the UHC within 125 pc radius is as large as ~3 × 108 M☉, an order of magnitude more massive than that in the same area of the Galactic center, and the mean density is as high as ~3 × 103H2 cm-3. A position-velocity diagram along the major axis indicates that the rotation curve already starts at a finite velocity exceeding 300 km s-1 from the nucleus. The surface mass density in the central region is estimated to be as high as ~105 M☉ pc-2, producing a very deep gravitational potential. We argue that the very large differential rotation in such a deep potential will keep the UHC gravitationally stable during the current star formation.