High Precision, Directly Determined Radii and Effective Temperatures for Giant Stars

高精度、直接确定巨星的半径和有效温度

• 批准号: 1212203
• 负责人: Gerard van Belle
• 金额: $ 34.18万
• 依托单位: Lowell Observatory
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1212203&HistoricalAwards=false
• 关键词: Precision; Directly; Determined; Radii; Effective

The investigators plan to significantly improve measurements of stellar temperatures and radii using optical interferometry of 425 giant stars, whose distances are accurately determined from a recent reanalysis of the Hipparcos dataset. Through direct measurements of effective temperature, linear radius and limb darkening, models that indirectly predict such values will be calibrated. They will use angular size data from the Palomar Testbed Interferometer (PTI) and Navy Optical Interferometer (NOI) in conjunction with spectrophotometry to directly determine temperature, radius, and stellar structure for the giant stars at unprecedented levels of accuracy. Optical and nearinfrared data will be used to constrain the bolometric fluxes, which in combination with PTI angular diameters will provide direct measures of temperature. This work will have broader impacts to many fields of stellar astrophysics, including structure, modeling, evolution, galactic spectral synthesis, exoplanetary science and planet/star formation theory. They will also participate in a public outreach program with Lowell Observatory.

研究人员计划使用425颗巨星的光学干涉测量法来显着改善恒星温度和半径的测量，这些巨星的距离是根据最近对依巴谷数据集的重新分析准确确定的。通过直接测量有效温度、线性半径和临边暗化，将校准间接预测这些值的模型。他们将使用来自Palomar试验台干涉仪（PTI）和海军光学干涉仪（NOI）的角尺寸数据，结合分光光度法，以前所未有的精度直接确定巨星的温度，半径和恒星结构。 光学和近红外数据将用于限制测热通量，与PTI角直径相结合将提供直接的温度测量。这项工作将对恒星天体物理学的许多领域产生广泛的影响，包括结构、建模、演化、星系光谱合成、系外行星科学和行星/星星形成理论。 他们还将参加洛厄尔天文台的一个公共外展计划。