论文标题
M81组的5DEG X 5DEG深HI调查：II。 IC 2574和Hijass J1021+68的HI分布和运动学
A 5deg x 5deg deep HI survey of the M81 group: II. HI distribution and kinematics of IC 2574 and HIJASS J1021+68
论文作者
论文摘要
我们分析了$ 5^\ Circ \ times5^\ circ $ circ $ circ $ deep hi调查，其中包含矮星系IC 2574和位于矮人和M81系统之间的HI Complex Hijass J1021+68。数据表明，IC 2574具有扩展的HI信封，该信封的形式以小云集合的形式连接到Hijass J1021+68，但是在IC 2574与M81组的中心成员之间没有发现明显的连接。我们基于形成Hijass J1021+68及其速度分布的云的形态，认为该复合物不是先前建议的黑色星系，而是从云中脱落的云层，或者掉落在IC 2574的原始hi上，或者落在IC 2574的原始hi上。我们还使用了深度的HIS绘制近距离的IC 2574的近距离iC 25744444。银河系的旋转曲线比以前更大。将所获得的旋转曲线与文献中的更高分辨率曲线相结合，我们限制了银河系的暗物质光环参数。
We analyse the eastern region of a $5^\circ\times5^\circ$ deep HI survey of the M81 group containing the dwarf galaxy IC 2574 and the HI complex HIJASS J1021+68, located between the dwarf and the M81 system. The data show that IC 2574 has an extended HI envelope that connects to HIJASS J1021+68 in the form of a collection of small clouds, but no evident connection has been found between IC 2574 and the central members of the M81 group. We argue, based on the morphology of the clouds forming HIJASS J1021+68 and its velocity distribution, that the complex is not a dark galaxy as previously suggested, but is instead a complex of clouds either stripped from, or falling onto the primordial HI envelope of IC 2574. We also use the deep HI observations to map the extended HI envelope around IC 2574 and, using a 3D tilted-ring model, we derive the rotation curve of the galaxy to a larger extent than has been done before. Combining the obtained rotation curve to higher resolution curves from the literature, we constrain the galaxy's dark matter halo parameters.
