A comprehensive study of dark halo with a large CCD camera

利用大型 CCD 相机对暗晕进行综合研究

基本信息

批准号：
11694071
负责人：
MURAKI Yasushi
金额：
$ 10.5万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A).
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11694071/
关键词：
gravitational microlensing Magellanic cloud black hole extra-solar planet EAGLE event long-period variables dark matter difference imaging analysis 重力レンズ CCDカメラ地球型惑星ガンマ線バースト星の大量連続測光

项目摘要

It is now well known that the Universe is filled with 'dark' matter. In order to investigate dark matter in the form of black holes and small low luminosity stars as well as to detect extra-solar planets, we have set up the MOA collaboration together with astronomers in New Zealand. We use the phenomenon of gravitational micro-lensing to detect such objects by observing the variations of the brightness of field stars produced by intervening dark, massive objects. See http : //www.vuw.ac.nz/scps/moa/.To date we have observed 4.4 million stars in the Large Magellanic cloud, 930 thousand stars in the Small Magellanic Cloud and 5.9 million stars in the bulge of our own galaxy. As a result of these observations, which have involved the analysis of enormous amounts of data by our group, we have :1) discovered a very interesting event in which the light intensity from a star increased over a period of 80 days, suggesting (with 40% probability) that a black hole was involved ;2) found indicati … More ons for the presence of one or even two Earth-sized planets close to a lens star and published the results in the Astrophysical Journal (this may be the first observation of such small planets and was given wide publicity in New Zealand and Japanese news media - radio TV and newspapers) and have shown that most planetary systems do not contain Jupiter-like planets ;3) developed a new method of data analysis based on a differential imaging technique which has been used since May 2000 to issue alerts of possible candidates for micro-lensing events to the world-wide astronomical community. This has been much appreciated since the MACHO collaboration stopped their alerts in 1999 and only MOA can observe the Large Magellanic Cloud in winter time ;4) have found examples of so-called EAGLE events, which differ from the usual gravitational lensing by their sharply-rising light curve, and which provide greater sensitivity for dark matter and planet detection.5) confirmed the existence of the overtone pulsators in Mira variables in the Large Magellanic Cloud and are now examining their nature together with appropriate magnitude and color calibrations.In future, in order to obtain much better information on the dark matter problem and to learn more about extra-solar planets and their formation, it will be necessary to introduce a 1.5 metre, f=4 telescope into the program. Less

现在众所周知，宇宙中充满了“暗”物质，为了研究黑洞和小型低光度恒星形式的暗物质以及探测太阳系外行星，我们建立了 MOA 合作组织。我们与新西兰的天文学家一起利用引力微透镜现象，通过观察由暗质量天体产生的场恒星的亮度变化来探测此类天体。 //www.vuw.ac.nz/scps/moa/。迄今为止，我们已在大麦哲伦星云中观测到 440 万颗恒星，在小麦哲伦云中观测到 93 万颗恒星，在我们银河系的核球中观测到 590 万颗恒星。这些观察结果涉及我们小组对大量数据的分析，我们：1）发现了一个非常有趣的事件，其中恒星的光强度在 80 天内增加，这表明（有 40% 的概率）涉及黑洞；2) 发现了靠近透镜恒星存在一颗甚至两颗地球大小的行星的迹象，并将结果发表在《天体物理学杂志》上（这可能是首次观测到此类小行星，并在新西兰和日本新闻媒体（广播电视和报纸）上进行了广泛宣传），并表明大多数行星系统不包含类木星行星；3）开发了一种基于一种差分成像技术，具有自 2000 年 5 月起，它就被用来向全世界天文学界发出可能发生微透镜事件的警报，自从 MACHO 合作组织于 1999 年停止发出警报以来，只有 MOA 可以在冬季观测大麦哲伦星云。时间;4) 发现了所谓的 EAGLE 事件的例子，它与通常的引力透镜不同，其光变曲线急剧上升，并且为暗物质和行星探测提供了更高的灵敏度。5)证实了大麦哲伦星云中米拉变星中泛音脉动器的存在，现在正在检查它们的性质以及适当的星等和颜色校准。将来，为了获得有关暗物质问题的更好信息并了解更多关于暗物质问题的信息-太阳行星及其形成，需要在程序中引入1.5米、f=4的望远镜。