Formation and Physical Properties of Substellar Objects

这项工作的目标是探索棕矮星的多样性，确定星下双星的物理性质，寻找低温/低质量的棕矮星和行星伴星。这是因为为了理解它们的形成，需要更好的恒星下人口统计特性。将使用的技术是对大样本棕矮星进行高角度分辨率的红外成像，以揭示双星伴星(并提取该种群的双星频率、分离分布和质量比分布)，并搜索极低温度(Y级棕矮星和行星)伴星，以及成像加上近红外光谱，以确定双星成员的物理性质(特别是动力学质量和温度，这反过来可用于检验理论模型)。该项目将使用凯克激光制导恒星自适应光学系统进行。一名博士后将接受激光制导恒星自适应天体的培训--这是天文学社区内一个日益增长的潜在非常重要的工具。本科生的培训也包括在内，他们将通过美国国家科学基金会赞助的夏威夷天文学研究所的本科生研究经验计划参与其中。

AST-0507833Michael LiuUniversity of HawaiiFormation and Physical Properties of Substellar ObjectsABSTRACTThe goal of the work is to explore the multiplicity of brown dwarfs, to determine the physicalproperties of substellar binaries, and to find low-temperature/low-mass brown dwarf and planetarycompanions. This is motivated by the need for better statistical properties of substellar populationsin order to understand their formation. The techniques to be used are high angular resolutioninfrared imaging of large samples of brown dwarfs to reveal binary companions (and extract thebinary frequency, separation distribution, and mass ratio distribution of the population) and tosearch for very low temperature (Y-class brown dwarf and planetary) companions, and imagingplus near-IR spectroscopy to determine the physical properties of the binary members (particularlydynamical masses and temperatures, which can in turn be used to test theoretical models). Theproject will be carried out using the Keck Laser Guide Star Adaptive Optics system.A postdoctoral fellow will be trained in laser guide star adaptive objects - a growing and potentiallyvery important tool within the astronomical community. The training of an undergraduate is alsoincluded, who will participate through the NSF sponsored Research Experiences forUndergraduates program at the Institute for Astronomy at Hawaii.