Physical description of turbulent and gravitationally bound structures in molecular clouds in relation to the modeling of the general cloud structure

分子云(MC)是恒星形成的自然环境。拟议的项目主要集中在局部重力塌陷之前的早期演化阶段(S)。它旨在加深我们对MC中可能是恒星或星团祖先的致密结构(团)的理解，以及对团的物理特征与一般云结构之间的联系的理解。该项目的两个主要目标是：1)对MC的总体结构进行模拟，并作为模型的组成部分推导出星团和恒星前核心的质量分布；2)对高质量观测数据和数值数据广泛使用的星团发现技术进行方法学比较，这将使我们能够反复阐述描述星团的统计方法。第一个目标是通过另一种用于描述星团的统计方法，以及通过探索真实云中或在模拟有重力的湍流星际介质所获得的数值数据集中的体积和柱密度分布的特性来实现第一个目标。描述自引力星前核心的统计方法的扩展也被预见到。该项目的第二个目标是通过深入研究利用基于不同物理前提的GaussClumps和Dendrogram算法检测到的团块的特征来实现。

The molecular clouds (MCs) are the natal environment for star formation. The proposed Project is focused mainly on their early evolutionary stage which precedes local gravitational collapse(s). It aims to deepen our understanding on the dense structures (clumps) in MCs that might be progenitors of stars or stellar clusters and on the link between clump physical characteristics and general cloud structure. Two main objectives of this Project are: i) modeling of MC general structure and derivation of the mass distributions of clumps and prestellar cores as integral components of the model; and, ii) methodological comparison between widely used clump-finding techniques applied to high-quality observational and numerical data which would enable iterative elaboration of the statistical approach for clump description. The first objective is to be achieved through alternative formulation of the statistical approach for clump description as well through exploring the properties of the volume- and column-density distributions in real clouds or in numerical datasets obtained from simulations of turbulent interstellar media with gravity. An extension of the statistical approach to describe self-gravitating prestellar cores is also foreseen. The second objective of the Project is to be achieved through in-depth study of characteristics of clumps detected by use of the algorithms Gaussclumps and Dendrograms which are based on different physical premises.