"砖“不是砖：中央分子带云G0 .253+0.016的结构和动力学的综合研究
'The Brick' is not a brick: A comprehensive study of the structure and dynamics of the Central Molecular Zone cloud G0.253+0.016
摘要：
在本文中，我们提供了G0.253+0.016（a.k.a.“砖块”）;银河系中最大和最密集的分子云之一，缺乏广泛的恒星形成的迹象。作为未来一代大质量恒星的潜在宿主，了解像G0.253+0.016这样的大部分静止分子云至关重要。在本文中，我们重新分析阿塔卡马大型毫米阵列周期0 HNCO $J=4(0,4)-3(0,3)$数据在3毫米，使用两个新的软件，我们提供给社会。首先，scousepy，一个谱线拟合算法scouse的Python实现。其次，acorns（Agglomerative Clustering for Organising Nested Structures），一种设计用于离散光谱数据的分层n维聚类算法。总之，这些工具提供了一个公正的测量视线速度分散在这个云，$σ_{v_{los}, {\rm 1D}}=4.4\pm2.1$公里$^{-1}$，这是有点大于预测的速度分散的大小关系的中央分子区（CMZ）。质心速度在天空平面上的分散是相当的，产生$σ_{v_{los}, {\rm 1D}}/σ_{v_{pos}, {\rm 1D}}\sim1.2\pm0.3$。这种各向同性可以表明云的视线范围近似等于天空平面中的视线范围。结合我们的运动学分解与辐射转移模型，我们得出结论，G0.253+0.016不是一个单一的，连贯的，和中央凝聚的分子云，“砖”不是一个\emph{brick}。相反，G0.253+0.016是一个动力学复杂和层次结构的分子云，其形态与CMZ中的轨道动力学和剪切的影响一致。
英文摘要：
In this paper we provide a comprehensive description of the internal dynamics of G0.253+0.016 (a.k.a. 'the Brick'); one of the most massive and dense molecular clouds in the Galaxy to lack signatures of widespread star formation. As a potential host to a future generation of high-mass stars, understanding largely quiescent molecular clouds like G0.253+0.016 is of critical importance. In this paper, we reanalyse Atacama Large Millimeter Array cycle 0 HNCO $J=4(0,4)-3(0,3)$ data at 3 mm, using two new pieces of software which we make available to the community. First, scousepy, a Python implementation of the spectral line fitting algorithm scouse. Secondly, acorns (Agglomerative Clustering for ORganising Nested Structures), a hierarchical n-dimensional clustering algorithm designed for use with discrete spectroscopic data. Together, these tools provide an unbiased measurement of the line of sight velocity dispersion in this cloud, $σ_{v_{los}, {\rm 1D}}=4.4\pm2.1$ kms$^{-1}$, which is somewhat larger than predicted by velocity dispersion-size relations for the Central Molecular Zone (CMZ). The dispersion of centroid velocities in the plane of the sky are comparable, yielding $σ_{v_{los}, {\rm 1D}}/σ_{v_{pos}, {\rm 1D}}\sim1.2\pm0.3$. This isotropy may indicate that the line-of-sight extent of the cloud is approximately equivalent to that in the plane of the sky. Combining our kinematic decomposition with radiative transfer modelling we conclude that G0.253+0.016 is not a single, coherent, and centrally-condensed molecular cloud; 'the Brick' is not a \emph{brick}. Instead, G0.253+0.016 is a dynamically complex and hierarchically-structured molecular cloud whose morphology is consistent with the influence of the orbital dynamics and shear in the CMZ.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
