论文标题
a-sloth:通过追踪光环的古代明星和当地可观察
A-SLOTH: Ancient Stars and Local Observables by Tracing Halos
论文作者
论文摘要
星系被认为位于暗物质的大重力结构内,所谓的光环。尽管这些光环中最小的没有恒星或仅有几颗星星,但最大的托管了整个星系簇。在宇宙历史上,光环经常碰撞和合并,形成越来越大的结构。合并树,即光环的目录在成长和合并时之间不断发展的连接,已成为描述和理解宇宙学对象(例如我们的银河系)历史的重要工具。半分析模型建立在此类合并树之上,是宇宙学理论研究的常见方法。当需要考虑的空间和时间尺度的动态范围对于数值模拟而言太大时,此类模型的半分析性质尤其有益。通过追踪光环(A-Slos)的古代恒星和当地可观察的物体是一种半分析模型,旨在以快速且易于访问的方式模拟早期宇宙中的恒星形成。它使用合并树,是从数值模拟中或由统计算法生成的,以描述星系的历史。用近似值和统计模型描述了重型物理学的过程,特别是气体冷却,恒星形成和恒星反馈。该模型的应用程序范围是广泛的,因此,我们将其提供给科学界。
Galaxies are thought to reside inside of large gravitationally bound structures of dark matter, so-called haloes. While the smallest of these haloes host no or only a few stars, the biggest host entire clusters of galaxies. Over cosmic history, haloes often collided and merged, forming bigger and bigger structures. Merger trees, i.e., catalogues of haloes evolving and connections between them as they grow and merge, have become a vital tool in describing and understanding the history of cosmological objects such as our Galaxy. Semi-analytical models, built on top of such merger trees, are a common approach for theoretical studies in cosmology. The semi-analytical nature of such models is especially beneficial when the dynamic range in spatial and time scales that need to be considered becomes too large for numerical simulations. Ancient Stars and Local Observables by Tracing Halos (A-SLOTH) is such a semi-analytical model and it is designed to simulate star formation in the early Universe in a fast and accessible way. It uses merger trees, either from numerical simulations or generated by statistical algorithms to describe the history of galaxies. The processes of baryonic physics, in particular gas cooling, star formation and stellar feedback are described with approximations and statistical models. The range of applications for this model is extensive and we, therefore, make it available to the scientific community.