Collaborative Research: CEDAR--Optical Aeronomical Observations at Millstone Hill

调查人员将升级和重建马萨诸塞州米尔斯石山天文台的光学仪器。 这些仪器包括一个新的巡逻法布里-珀罗干涉仪（FPI），一个全天空多普勒成像仪（ASDI）和一个光谱仪。 观测结果将用于系统地解决中间层和热层物理学中的一些问题。 研究工作将包括利用FPI综合的中间层和热层多普勒风以及来自羟基和氧排放的全天图像和非相干散射雷达观测，研究中纬度中间层和低热层潮汐。 半日潮通常具有较大的垂直波长，因此组合观测将在白天和夜间提供较大的垂直高度覆盖范围，并将允许更好地表征垂直潮汐结构。 此外，Millstone Hill的全天空成像仪将记录重力波活动的羟基，钠和氧夜光排放，研究人员将使用来自相同排放的FPI中性风来计算固有重力波参数。 从内在参数，他们将推导出波的传播模式和几个重要的波参数，包括垂直尺度大小的定量测量，水平波动量和能量的垂直通量的估计，以及气辉层，特别是羟基和氧层之间的波通量发散量。 FPI中性风和温度测量将用于研究中间层和热层与太阳活动周期有关的长期趋势，并将使用全天多普勒成像仪研究小尺度热层温度和中性风的变化。 光学仪器的区域集群与Millstone Hill非相干散射雷达相结合，将提供从中间层到热层的全面覆盖。 它们将为研究MLT动力学和亚极光区电离层/热层相互作用提供独特的数据集。 多个研究所的参与将促进不同研究小组之间的更多合作。 Millstone Hill光学仪器也将成为未来分布式仪器项目的测试平台。

The investigators will upgrade and rebuild optical instruments at the Millstone Hill Observatory in Massachusetts. The instruments include a new patrol Fabry-Perot interferometer (FPI), an all-sky Doppler imager (ASDI), and a spectrometer. The observations will be used to systematically address a number of issues in mesospheric and thermospheric physics. Research will include the study of mid-latitude mesosphere and lower thermosphere (MLT) tides using the combined FPI mesospheric and thermospheric Doppler winds and all-sky images from hydroxyl and oxygen emissions and incoherent scatter radar observations. The semidiurnal tide usually has a large vertical wavelength so the combined observations will provide a large vertical altitude coverage during both the day and night, and will allow for a better characterization of the vertical tidal structure. Also, the all-sky imager at Millstone Hill will record the hydroxyl, sodium, and oxygen nightglow emissions for gravity wave activity and the investigators will use the FPI neutral winds from the same emissions to calculate the intrinsic gravity wave parameters. From the intrinsic parameters, they will deduce the propagation modes of the waves and several important wave parameters including quantitative measurements of vertical scale-sizes, estimates of the vertical fluxes of horizontal wave momentum and energy, and the amount of wave flux divergence between the airglow layers, the hydroxyl and oxygen layers, in particular. The FPI neutral wind and temperature measurements will be used to study the long-term trends in the mesosphere and thermosphere in connection with the solar cycles, and small-scale thermosphere temperature and neutral wind variations will be studied using the all sky Doppler imager. The regional cluster of optical instruments in conjunction with the Millstone Hill Incoherent Scatter radar will provide comprehensive coverage from the mesosphere to the thermosphere. They will provide a unique data set for studies of MLT dynamics and ionosphere/thermosphere interaction in the sub-auroral region. Multi-institute participation will foster more collaboration between different research groups. The Millstone Hill optical instruments will also be the test bed for the future distributed instrument projects.