Galactic Cold Interstellar Filaments: Structure, Kinematics, and Chemistry

银河冷星际丝：结构、运动学和化学

• 批准号: 263084949
• 负责人: Dr. Ke Wang
• 金额: --
• 依托单位: Europäische Südliche Sternwarte (ESO)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/263084949?language=en
• 关键词: Galactic; Cold; Interstellar; Filaments; Structure

Molecular interstellar medium is known to be highly hierarchical and filamentary. Studies in recent years have demonstrated the importance of filaments in star formation, at scales of <10 pc and >100 pc, and suggest a new paradigm for star formation. However, extremely filamentary giant molecular clouds (GMCs) at scales between 10 and 100 pc have not been studied systematically. A compelling sample does not exist at the first place, due to a historical limitation in the identifying methodology (i.e., extinction). In this project, we use the full Hi-GAL images to directly search for large filaments in the entire Galactic plane. We select a sample of 9 most prominent filaments with a length of 30-103 pc and mass (2.4-19)x10^4 Msun. The filaments are cold compared to surroundings and show no significant internal heating. This makes our project unique in probing the early evolutionary phases to study the connection of filamentary GMCs to the onset of star formation. We propose to perform a first systematic characterization of these filaments focusing on their hierarchical structure, kinematics, and core chemistry, aiming to reveal a comprehensive picture of high-mass star formation in the context of large filaments. The methods are designed so that results are directly comparable to numerical simulations and theoretical predictions. This is a timely project making use of the newly available Hi-GAL data, and will fill the gap between Galactic and local filaments, towards an understanding of filaments at all spatial scales.

分子星际介质是一种高度分层的、非连续的介质。近年来的研究已经证明了细丝在星星形成中的重要性，在100 pc的尺度上<10 pc and >，并提出了星星形成的新范式。然而，在10和100 pc之间的尺度上，极不连续的巨分子云（GMC）还没有被系统地研究。由于识别方法的历史局限性（即，灭绝）。在这个项目中，我们使用完整的Hi-GAL图像来直接搜索整个银河系平面中的大细丝。我们选取了一个由9个最突出的细丝组成的样本，长度为30-103 pc，质量为（2.4 ~ 19）× 10^4 Msun。与周围环境相比，灯丝是冷的，并且没有显示出明显的内部加热。这使得我们的项目在探索早期演化阶段以研究非线性GMC与星星形成的开始之间的联系方面是独一无二的。我们建议执行第一个系统的表征，这些灯丝集中在他们的层次结构，运动学和核心化学，旨在揭示一个全面的图片大质量星星形成的背景下，大灯丝。该方法的设计，使结果直接与数值模拟和理论预测。这是一个及时的项目，利用新获得的Hi-GAL数据，并将填补银河系和本地细丝之间的差距，以了解所有空间尺度的细丝。