CEDAR: Terrestrial Airglow Studies Using Astronomical Sky Spectra

CEDAR：使用天文天空光谱进行地面气辉研究

• 批准号: 0437361
• 负责人: Tom Slanger
• 金额: $ 26.09万
• 依托单位: SRI International
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-01-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0437361&HistoricalAwards=false
• 关键词: CEDAR; Terrestrial; Airglow; Studies; Using

Spectra of the night sky gathered as a by-product of astronomical observations made at two Keck telescopes at Mauna Kea, Hawaii are used to improve our understanding of chemistry and composition in the upper mesosphere and thermosphere. The data acquisition has recently expanded to include similar spectrographic data from the European Southern Observatory in Chile, and from the 9-meter telescope at McDonald Observatory in Texas. The use of the data for aeronomy focuses on three discoveries made in a preceding research effort. First, a ratio of the sodium D1 to D2 emission intensity is found to have a surprising semiannual oscillation, which preliminary investigation indicates is modulated by the O:O2 number density ratio in the upper mesosphere. This research attempts to prove that hypothesis, and thereby establish an unprecedented proxy for determining the density of the dominant species in the upper atmosphere - a long standing and elusive target for ground-based aeronomy. The second research task investigates the ratio of the O(1D):N(2D) ratio (the latter a unique measurement capability of these large telescopes) relative to model values that currently do not reproduce the data. The third research task uses the heretofore unappreciated detail of the OI Rydberg series to peg ratios that can be used for instrument sensitivity calibration throughout the airglow observation community - and thereby improve density determinations made from airglow data.

夏威夷莫纳克亚山的两台凯克望远镜收集的夜空光谱是天文观测的副产品，用于增进我们对上层中间层和热层的化学和成分的理解。 数据采集​​最近已扩大到包括来自智利欧洲南方天文台和德克萨斯州麦克唐纳天文台 9 米望远镜的类似光谱数据。 航空学数据的使用集中于先前研究工作中的三项发现。 首先，发现钠 D1 与 D2 发射强度的比率具有令人惊讶的半年振荡，初步研究表明该比率受到上层中间层中 O:O2 数密度比的调节。 这项研究试图证明这一假设，从而建立一个前所未有的代理来确定高层大气中主要物种的密度——这是地面航空学长期存在且难以捉摸的目标。 第二个研究任务研究 O(1D):N(2D) 比（后者是这些大型望远镜的独特测量能力）相对于当前无法再现数据的模型值的比率。 第三项研究任务使用迄今为止未被重视的 OI Rydberg 系列与钉比率的细节，可用于整个气辉观测界的仪器灵敏度校准，从而改进根据气辉数据进行的密度测定。