Observations with Infrared Space Observatory (ISO)

该项目打算通过国际联合研究，利用红外空间观测站上的液氦冷却空间望远镜，寻找正在形成的星系，并研究恒星演化最后阶段的物理学。我们的ISO观测包括：（1）在Lockman Hole进行ISO深红外巡天，以寻找光学巡天可能遗漏的正在形成的星系;（2）对麦哲伦云中的星星团中心部分进行ISO红外成像，以研究极晚期恒星的质量损失;以及（3）对发射线进行光谱测绘，以探测年轻热星附近的光电离结构。我们要通过检查ISO的标定数据，了解ISO仪器在太空中的特性，并进行地面跟踪观测，允许我们派6名科学家到法国分析ISO仪器的特性。因此，我们现在比以前更好地了解ISO工具及其行为，为减少数据提供了坚实的基础。在此基础上，我们基本完成了ISO深红外巡天项目的数据处理工作，并计划进行KPNO和IRAM的后续观测，随后合作者为寻求更好的观测设备而努力，使加州理工大学亚毫米波天文台的10米亚毫米波望远镜和夏威夷大学的2.2米光学望远镜成为可能。在这次观测中，我们发现：（1）ISO远红外源的面密度比非演化模型估计的高10倍，（2）非常晚的恒星富含分子和尘埃，这是任何现有的恒星大气模型都无法解释的。

This project intends to search for forming galaxies and investigate physics at the last evolutionary stage of stars by using the liquid-helium-cooled space telescope onboard the Infrared Space Observatory (ISO) via international joint research. Our ISO observations include (1) ISO deep infrared survey in the Lockman Hole to search for forming galaxies which might have been missed in the optical surveys, (2) ISO multicolor imaging of central parts of star clusters in the Magellanic Clouds to study mass-loss of very-late stars, and (3) spectroscopic mapping of emission lines to probe the photo-ionized structure near young hot stars.To achieve the above objectives, we had to understand the characteristics of the ISO instrument in space through examining ISO data taken for calibration, and carry out follow-up observations from the ground.We were allowed to send six scientists to France to analyze the characteristics of the ISO instrument. As a result, we now understand the ISO instrument and their behavior much better than before, providing the firm basis for reducing data. Accordingly, we have almost completed the data reduction, which is especially true to the ISO deep infrared survey project.Follow-up observations were initally planned to carry out KPNO and IRAM.Subsequent efforts made by collaborators for seeking better observing facilities made it possible to use the 10m sub-millimeter telescope in the Caltech Sub-millimeter Observatory and the 2.2m optical telescope of the University of Hawaii, both located in the Mauna Kea Observatory, Hawaii, USA.The follow-up observations have just started, which will be continued for the next several months.During this project, we found (1) the surface density of ISO far-infrared sources is 10 times higher than expected from the non-evolution model, and (2) very late stars are rich in molecules and dust which cannot be explained by any existing models of stellar atmosphere.