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

研究人员将升级和重建马萨诸塞州磨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），一个全天多普勒成像仪（ASDI）和一个光谱仪。这些观测结果将用于系统地解决中间层和热层物理中的一些问题。研究将包括研究中纬度中间层和低层热层（MLT）潮汐，使用FPI结合的中间层和热层多普勒风和来自羟基和氧气发射的全天图像以及非相干散射雷达观测。半日潮通常具有较大的垂直波长，因此综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。同时，Millstone Hill的全天成像仪将记录重力波活动的羟基、钠和氧夜光发射，研究人员将使用来自相同发射的FPI中性风来计算内在重力波参数。从固有参数中，他们将推导出波的传播模式和几个重要的波参数，包括垂直尺度尺寸的定量测量，水平波动量和能量的垂直通量的估计，以及气辉层之间，特别是羟基层和氧层之间的波通量散度的量。FPI中性风和温度测量将用于研究与太阳周期有关的中间层和热层的长期趋势，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。区域光学仪器集群与磨石山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。它们将为亚极光区MLT动力学和电离层/热层相互作用的研究提供独特的数据集。多研究所参与将促进不同研究小组之间的更多合作。磨石山光学仪器也将成为未来分布式仪器项目的试验台。

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.