Towards a Comprehensive Understanding of Brown Dwarf Atmospheres

全面了解棕矮星大气

基本信息

批准号：
1517015
负责人：
Jonathan Fortney
金额：
$ 24.53万
依托单位：
University of California-Santa Cruz
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2015
资助国家：
美国
起止时间：
2015-09-01 至 2018-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1517015&HistoricalAwards=false
关键词：
Towards Comprehensive Understanding Brown Dwarf

项目摘要

Brown dwarfs are objects that sit at the boundary between stars and planets. Although they form like stars, they do not have hydrogen fusion, so they cool over billions of years down to temperatures similar to those of planets. By studying the the infrared heat radiation given off by brown dwarfs, we can understand the physics and chemistry and their atmospheres. This project involves the work of graduate students and high school students, who will receive training in advanced computational techniques, which will allow them to create computer models of brown dwarf atmospheres. These results will be compared to observations made from large telescopes in order to determine the physical properties within brown dwarf atmospheres. The proposal team will carry out a significant expansion of the phase space of brown dwarf model atmospheres. They will investigate the role of metallicity, non-solar carbon-to-oxygen ratios, varied cloud thickness, cloud coverage fraction, surface gravity, and other factors in shaping brown dwarf spectra. This extensive grid of radiative-convective "forward models" will map out the phase space of brown dwarf atmospheric chemistry and physics. For the first time we will gain a quantitative understanding of the reasons behind mismatches between spectral observations and models. The bulk of the science will be performed by a graduate student, in concert with high school interns who will be mentored each summer.

褐矮星是位于恒星和行星之间边界的天体。虽然它们像恒星一样形成，但它们没有氢聚变，因此它们在数十亿年的时间里冷却到与行星相似的温度。通过研究褐矮星发出的红外热辐射，我们可以了解其物理、化学及其大气层。该项目涉及研究生和高中生的工作，他们将接受先进计算技术的培训，这将使他们能够创建棕矮星大气的计算机模型。这些结果将与大型望远镜的观测结果进行比较，以确定棕矮星大气层内的物理特性。提案团队将对褐矮星模型大气的相空间进行显着扩展。他们将研究金属丰度、非太阳碳氧比、变化的云厚度、云覆盖率、表面重力和其他因素在形成棕矮星光谱中的作用。这个广泛的辐射对流“正演模型”网格将绘制出褐矮星大气化学和物理的相空间。我们将第一次定量地了解光谱观测与模型之间不匹配的原因。大部分科学工作将由一名研究生与每年夏天接受指导的高中实习生合作完成。