Systematics Searches for Brown Dwarfs and Planets

褐矮星和行星的系统学搜索

基本信息

批准号：
14540232
负责人：
NAKAJIMA Tadashi
金额：
$ 2.05万
依托单位：
National Astronomical Observatory of Japan
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540232/
关键词：
Brown Dwarfs Dark Matter Fermi-Dirac degeneracy 太陽系外惑星低質量星

项目摘要

FY2004 is the last year of this grant and we have made our scientific results public by articles in academic journals and by an invited paper at an international workshop relavant to brown dwarf research. First, as to the relation between the spectral classification and effective temperature of brown dwarfs, we have found constancy of effective temperature between spectral types late L and early T (Nakajima, Tsuji, and Yanagisawa 2004,ApJ). Second, we interpretated the variation of spectral features from the point of view of atmospheric modeling (Tsuji, Nakajima & Yanagisawa 2004,ApJ). Third, we have started a systematic search for brown dwarfs and planets using Subaru, beginning August 2004,and its interim report has been presented as an invited paper at the workshop on "Ultra Low Mass Stars Formation" workshop held at La Palma, Spain. The content of the invitated paper is going to be published in an European refereed journal, Astronomical Notes in December 2005. Brown dwarfs used to be a candidate for disk dark matter and from the point of view of internal physics, evolved brown dwarfs are low temperature degenerate stars, supported by electron degeneracy pressure. As an application of brown dwarf interior physics, we have shown that if dominant dark matter consists of eV-mass fermiqns, the flat-top density profile of the center of a cluster of galaxies can be explained by degeneracy pressure of the light fermions (Nakajima & Morikawa 2005,ApJ submitted). Finally in August 2005,we have compiled the scientific results over the 3 year grant period and published a booklet, summarizing our work. The size of the booklet is A4 and it consists of 153 pages.

2004 财年是这项资助的最后一年，我们通过学术期刊上的文章和与褐矮星研究相关的国际研讨会上的邀请论文公开了我们的科学成果。首先，关于褐矮星的光谱分类与有效温度之间的关系，我们发现L晚期和T早期的光谱类型之间的有效温度具有恒定性（Nakajima，Tsuji和Yanagisawa 2004，ApJ）。其次，我们从大气建模的角度解释了光谱特征的变化（Tsuji, Nakajima & Yanagisawa 2004,ApJ）。第三，从2004年8月开始，我们开始使用Subaru系统地搜索褐矮星和行星，其中期报告已作为特邀论文提交给在西班牙拉帕尔马举行的“超低质量恒星形成”研讨会。受邀论文的内容将于2005年12月发表在欧洲审稿期刊《Astronomical Notes》上。褐矮星曾经是盘状暗物质的候选者，从内部物理的角度来看，演化而来的褐矮星是低温的。简并恒星，由电子简并压力支持。作为褐矮星内部物理学的应用，我们已经证明，如果主要暗物质由 eV 质量费米子组成，则星系团中心的平顶密度剖面可以通过轻费米子的简并压力来解释（Nakajima & Morikawa 2005，ApJ 提交）。最终在2005年8月，我们汇编了3年资助期内的科学成果，并出版了一本小册子，总结了我们的工作。该册子尺寸为A4，共有153页。