Interactions of the Galactic bar and spiral arm in NGC 3627
Interactions of the Galactic bar and spiral arm in NGC 3627
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NGC 3627 中银河棒和旋臂的相互作用
DOI：
10.1051/0004-6361/201526749
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发表时间：
2017
影响因子：
6.5
通讯作者：
A. Leroy
中科院分区：
文献类型：
--
作者：
H. Beuther;S. Meidt;E. Schinnerer;R. Paladino;A. Leroy
目的：为了深入了解我们银河系中银河棒和旋臂界面处的预期气体动力学，我们将作为河外对应物的证据放在冷致密分子气体中的多个不同速度分量的证据中，这些分子气体填充在附近星系 NGC 3627 棒末端的类似区域。
方法：我们组装了由 CO(2-1) 排放追踪的分子气体运动学的高分辨率视图，并从高和低气体速度分散区域提取了视线速度剖面。
结果：高速分散体通常具有双峰或多线轮廓。我们将不同速度分量的质心与基于存在条形和螺旋势扰动的轨道动力学的期望进行比较。该区域的模型作为支撑棒和独立旋转旋臂的两个气体填充轨道族的界面，提供了与数据的总体良好匹配。星系共转半径的限制范围是有利的。
结论：以 NGC 3627 作为河外的例子，我们预计这样的情况有利于强烈的恒星形成事件，就像我们在银河系中观察到的那样，因为气体会在轨道族交叉的地方堆积。物质沿着这些轨道的相对运动对于该区域高密度的形成很可能更为重要。 NGC 3627 的表面密度也非常高，棒端的剪切不太可能显着削弱恒星形成活动。我们推测，条形和螺旋形以两种不同模式速度旋转的情况可能最有利于在此类界面处形成强烈的恒星。
Aims: To gain insight into the expected gas dynamics at the interface of the Galactic bar and spiral arms in our own Milky Way galaxy, we examine as an extragalactic counterpart the evidence of multiple distinct velocity components in the cold dense molecular gas that populates a similar region at the end of the bar in the nearby galaxy NGC 3627.
Methods: We assembled a high-resolution view of molecular gas kinematics traced by CO(2-1) emission and extracted line-of-sight velocity profiles from regions of high and low gas velocity dispersion.
Results: The high velocity dispersions arise with often double-peaked or multiple line-profiles. We compare the centroids of the different velocity components to expectations based on orbital dynamics in the presence of bar and spiral potential perturbations. A model of the region as the interface of two gas-populated orbits families supporting the bar and the independently rotating spiral arms provides an overall good match to the data. An extent of the bar to the corotation radius of the galaxy is favored.
Conclusions: Using NGC 3627 as an extragalactic example, we expect situations like this to favor strong star formation events such as are observed in our own Milky Way since gas can pile up where the orbit families cross. The relative motions of the material following these orbits is most likely even more important for the build-up of high density in the region. The surface densities in NGC 3627 are also so high that shear at the bar end is unlikely to significantly weaken the star formation activity. We speculate that scenarios in which the bar and spiral rotate at two different pattern speeds may be the most favorable for intense star formation at such interfaces.
通过测量图案速度的径向变化来揭示螺旋结构的起源
DOI：
10.1088/0004-637x/702/1/277
发表时间：
2009
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Meidt S
通讯作者：
Meidt S
M51、M33和大麦哲伦云巨分子云的比较研究
DOI：
10.1088/0004-637x/779/1/46
发表时间：
2013
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Hughes;Colombo;Schinnerer
通讯作者：
Schinnerer
影响因子：
6.5
作者：
P. Carlhoff;Q. N. Luong;P. Schilke;F. Motte;N. Schneider;H. Beuther;S. Bontemps;F. Heitsch;T. Hill;C. Kramer;V. Ossenkopf;F. Schuller;R. Simon;F. Wyrowski
通讯作者：
P. Carlhoff;Q. N. Luong;P. Schilke;F. Motte;N. Schneider;H. Beuther;S. Bontemps;F. Heitsch;T. Hill;C. Kramer;V. Ossenkopf;F. Schuller;R. Simon;F. Wyrowski