New Windows into the Substellar Mass Function

亚恒星质量函数的新窗口

• 批准号: 0407441
• 负责人: Michael Liu
• 金额: --
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0407441&HistoricalAwards=false
• 关键词: New; Windows; into; Substellar; Mass

This project is studying the formation of brown dwarfs by characterizing the initial mass distribution function of substellar objects. In order to understand the properties of the substellar population and to test theories of brown dwarf and star formation, two fundamental questions are being addressed: (1) what is the lowest mass object which can form in isolation, and (2) how does the substellar initial mass distribution vary with environment? Two spectrophotometric surveys are tailored to these questions on the basis of the unique spectral characteristics of substellar objects. The surveys look for the presence of methane absorption, typical of young brown dwarfs of 0.2 Jupiter masses, and for water absorption, present in the infrared spectra of all young brown dwarfs, and they take advantage of a new generation of wide-field infrared cameras with an unprecedented combination of sensitivity and field of view. Thus the substellar initial mass function is determined to much lower masses and over a much wider range of environments compared to previous work. The program will also produce a very populous sample of young brown dwarfs amenable for follow-up studies.

该项目通过描述亚恒星物体的初始质量分布函数来研究褐矮星的形成。 为了了解亚恒星群体的性质和测试理论的褐矮星和星星的形成，两个基本问题正在解决：（1）什么是最低质量的物体，可以形成孤立的，和（2）如何亚恒星初始质量分布随环境变化？ 两个分光光度调查是针对这些问题的基础上，独特的光谱特征的亚恒星物体。 这些调查寻找甲烷吸收的存在，这是0.2木星质量的年轻棕矮星的典型特征，以及所有年轻棕矮星红外光谱中存在的水吸收，它们利用了新一代宽视场红外相机，具有前所未有的灵敏度和视野。 因此，亚恒星的初始质量函数被确定为更低的质量和更广泛的环境相比，以前的工作。该计划还将产生一个非常多的年轻棕矮星样本，可用于后续研究。