High Precision Astrophysics: Magnetic Activity from Stars to Planets

高精度天体物理学：从恒星到行星的磁活动

• 批准号: 29408093
• 负责人: Professor Dr. Ansgar Reiners
• 金额: --
• 依托单位: Institut für Astrophysik und Geophysik
• 依托单位国家: 德国
• 项目类别: Independent Junior Research Groups
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/29408093?language=en
• 关键词: Precision; Astrophysics; Magnetic; Activity; Stars

Magnetic activity governs the properties of sun-like stars, it is the reason for solar irradiance variations and fundamental for a better understanding of the Sun-climate connection. Magnetic activity is ubiquitously observed in sun-like and cooler stars, and it is found in planet-like substellar objects, so-called brown dwarfs. Solar, stellar and substellar magnetic activity are manifestations of the same processes occurring in physically related objects that possess very different atmospheres and surface structure. In the proposed Emmy Noether group, we will systematically investigate magnetic activity, atmospheres and surface structure in sun-like stars and substellar objects that bridge the gap between the Sun and planets. Our goal is to provide a comprehensive picture of magnetic activity in stellar and substellar environments, and to understand solar activity in this context. Specifically, we will carry out high precision spectroscopic experiments in stars and brown dwarfs to investigate their atmospheres, surface properties and immediate drivers of magnetic activity. We will prepare the analysis of high precision photometric data from satellite missions, and we will collect and analyze such data for some 100 000 sun-like stars. To better understand physical conditions especially in very cool objects, we will observationally determine fundamental molecular constants that are difficult to obtain from laboratory measurements, but can be deduced from high precision astrophysics.

磁活动控制着类太阳恒星的特性，它是太阳辐照度变化的原因，也是更好地理解太阳与气候关系的基础。磁活动在类太阳和较冷的恒星中普遍存在，并且在类行星的亚恒星天体（即所谓的褐矮星）中也被发现。太阳、恒星和亚恒星的磁活动是在物理相关的天体中发生的相同过程的表现，这些天体具有非常不同的大气层和表面结构。在拟议的艾美·诺特小组中，我们将系统地研究类太阳恒星和连接太阳与行星之间间隙的亚恒星天体的磁活动、大气和表面结构。我们的目标是提供恒星和次恒星环境中磁活动的全面图片，并了解这方面的太阳活动。具体来说，我们将在恒星和褐矮星中进行高精度光谱实验，以研究它们的大气、表面特性和磁活动的直接驱动因素。我们将准备对卫星任务的高精度光度数据进行分析，并收集和分析约10万颗类太阳恒星的此类数据。为了更好地了解物理条件，特别是在非常冷的物体中，我们将通过观察确定基本分子常数，这些常数很难从实验室测量中获得，但可以从高精度天体物理学中推导出来。