Properties of Low Mass Stars and Brown Dwarfs: Single vs. Close Binary Environments

低质量恒星和褐矮星的特性：单一与紧密双星环境

• 批准号: 0205875
• 负责人: Suzanne Hawley
• 金额: $ 27.24万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0205875&HistoricalAwards=false
• 关键词: Properties; Low; Mass; Stars; Brown

AST 0205875PI HawleySloan Digital Sky Survey (SDSS) has demonstrated that it is an unsurpassed resource for finding low mass stars, brown dwarfs and close binaries such as cataclysmic variables. This project will use the ongoing SDSS photometric and spectroscopic data during the next 3 years to amass a large database on low mass stars, both single and in close binaries. Additional follow-up data will be obtained. Undergraduate and graduate students will participate in the observations and analysis of the data. An on-line database will be made available for scientists, the public, and outreach activities. Measurements of the magnitudes, colors, spectral types, magnetic activity levels, rotation rates and ages of the late type stars will be used to infer basic physical properties (temperature, luminosity, mass and strength of the magnetic dynamo), which then will be compared for objects at different evolutionary stages in both single and close binary environments to assess the dependence of magnetic activity on rotation rate, to discover and characterize close interacting binary systems with lower mass secondaries than have previously been found, study the influence of irradiation on the low mass secondaries in close binaries, to determine if this strongly affects the outbursts in cataclysmic variables, and to determine the space density and luminosity function of low mass single stars compared with their counterparts in binary systems. ***

AST 0205875PI HawleySloan Digital Sky Survey（SDSS）已经证明它是寻找低质量恒星、褐矮星和近距离双星（如激变变星）的无与伦比的资源。该项目将在今后三年内利用持续的SDSS光度和光谱数据，积累一个关于低质量恒星（包括单恒星和近距离双星）的大型数据库。将获得额外的随访数据。本科生和研究生将参与数据的观察和分析。将为科学家、公众和外联活动提供一个在线数据库。 晚型星的星等、颜色、光谱类型、磁活动水平、自转速率和年龄的测量将被用来推断基本的物理性质（温度、光度、质量和磁发电机的强度），然后将对处于不同演化阶段的单星和近距离双星环境中的天体进行比较，以评估磁活动对自转速率的依赖性，发现和表征具有比以前发现的更低质量秒数的紧密相互作用双星系统，研究辐照对紧密双星中低质量秒数的影响，确定这是否强烈影响激变变星的爆发，并确定与双星系统中对应物相比的低质量单星的空间密度和光度函数。***