当前位置:
X-MOL 学术
›
Int. J. Mod. Phys. D
›
论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Close stellar encounters kicking planets out of habitable zone in various stellar environments
International Journal of Modern Physics D ( IF 2.2 ) Pub Date : 2021-05-19 , DOI: 10.1142/s0218271821500632 Behzad Bojnordi Arbab 1 , Sohrab Rahvar 1
International Journal of Modern Physics D ( IF 2.2 ) Pub Date : 2021-05-19 , DOI: 10.1142/s0218271821500632 Behzad Bojnordi Arbab 1 , Sohrab Rahvar 1
Affiliation
Continuous habitability of a planet is a critical condition for advanced forms of life to appear, but it can be endangered by astronomical events such as stellar encounters. The purpose of this study is to analyze close stellar encounters able to change planetary orbits initially in circumstellar habitable zones and to investigate the expected encounter rates in a variety of stellar environments. Using gravitational simulations for three-body systems, this study analyzed the dependencies of encounter impact-parameters with kinematic, geometric, and habitability parameters of the system. We also used kinematic properties of various stellar regions and estimated encounter rates of the events. The expected number of threatening stellar encounters in the Solar neighborhood is ≈ 3 . 9 × 1 0 − 4 in 4 billion years, while for the Galactic bulge environment, we expect approximately 5.5 times the value. The encounter rates for other stellar environments are calculated and spheroidal dwarf galaxies and globular clusters encounter rates are estimated. The results show that in contrast with the solar neighborhood, close stellar encounters can play a significant role in the expected number of planets with continuous habitability in dense stellar environments. Another notable result shows that threatening stellar encounter rate follows the number density of stars, and is not strongly dependent of the region’s velocity dispersion. Further investigations are needed to study long-term multiple planetary systems and how they can change the overall expected value of continuously habitable planets.
中文翻译:
在各种恒星环境中,近距离的恒星相遇将行星踢出宜居区
行星的持续宜居性是高级生命形式出现的关键条件,但它可能会受到恒星相遇等天文事件的威胁。这项研究的目的是分析能够改变行星轨道的近距离恒星相遇,最初是在环绕恒星的宜居带,并调查在各种恒星环境中的预期相遇率。本研究使用三体系统的引力模拟,分析了遭遇撞击参数与系统运动学、几何学和可居住性参数的相关性。我们还使用了各种恒星区域的运动学特性和估计的事件遭遇率。在太阳附近的威胁性恒星相遇的预期数量是 ≈ 3 . 9 × 1 0 - 4 40 亿年后,而对于银河核球环境,我们预计该值约为 5.5 倍。计算其他恒星环境的遭遇率,并估计球状矮星系和球状星团的遭遇率。结果表明,与太阳邻域相比,近距离的恒星相遇可以在稠密恒星环境中具有连续可居住性的行星的预期数量中发挥重要作用。另一个值得注意的结果表明,威胁性恒星相遇率跟随恒星的数量密度,而不强烈依赖于该区域的速度分散。需要进一步的研究来研究长期的多行星系统以及它们如何改变连续宜居行星的整体预期价值。
更新日期:2021-05-19
中文翻译:
在各种恒星环境中,近距离的恒星相遇将行星踢出宜居区
行星的持续宜居性是高级生命形式出现的关键条件,但它可能会受到恒星相遇等天文事件的威胁。这项研究的目的是分析能够改变行星轨道的近距离恒星相遇,最初是在环绕恒星的宜居带,并调查在各种恒星环境中的预期相遇率。本研究使用三体系统的引力模拟,分析了遭遇撞击参数与系统运动学、几何学和可居住性参数的相关性。我们还使用了各种恒星区域的运动学特性和估计的事件遭遇率。在太阳附近的威胁性恒星相遇的预期数量是