太阳系外行星探测方法及统计特征  

The Detection Methods and Statistical Characteristics of Exoplanet

作　　者：张牛[1,2] 季江徽[1] 

机构地区：[1]中国科学院紫金山天文台,南京210008 [2]中国科学院研究生院,北京100039

出　　处：《天文学进展》2009年第1期14-28,共15页Progress In Astronomy

基　　金：国家自然科学基金资助项目(10573040,10673006,10833001,10203005);紫金山天文台小行星基金会资助课题

摘　　要：太阳系外行星的探测和研究在过去十几年取得了重大进展,仅2007年就发现62颗太阳系外行星,随着行星物理学、天体生物学等学科的兴起,必将掀起对太阳系外行星研究的一次浪潮。简要回顾了太阳系外行星研究的发展历史,介绍了探测太阳系外行星的主要方法和手段,并对方法本身的特点展开分析论述,列出了各种方法应用的最新进展。对已发现的270多颗太阳系外行星进行了统计分析,得出了一些预见性的结论。Since the first extrasolar planet was discovered in 1995, the detection and research of extrasolar planets has taken a big step forward in the last decade. To date, more than 270 planets orbiting solar-type stars were discovered, 62 of which were reported in 2007. The detection method developed rapidly. The paper briefly introduced several dorminant detection methods （e.g., Direct imaging, Astrometry, Radical velocity, Transit and Microlensing） of extrasolar planets. The radical velocity technique is most popular. It could yield all orbital elements except the orbital inclination. Most of the known planets were revealed by this method. Additionally, if the orbital inclination was obtained by transit/astrometry, then we could infer the composition of the extrasolar planet by computing their density. The Direct imaging is powerful. The spectrum of extrasolar planet could give direct clues of composition of the planet; however the measurement is very challenging. The planetary system can be detected far beyond our solar system even the planet is pretty smaller as our Earth, by using Microlensing method. The detailed principle and advantages/disadvantages of each method were discussed and the latest progress was also presented. The paper classified the known extrasolar planets into three categories （Planets in oblate orbit, Planets in quasi-circular orbit, 51 Peg-like planets） according to their orbital characteristics. In addition, the paper made a statistical study of the extrasolar planetary system using the latest data. The data shows： （i） mass, radii and distance from earth of the known extrasolar planets＇ center star are gathered, obviously this is a selection effect; （2） center stars with higher metallicity have more probability of harboring planet; （3） orbital characteristics of known planets are not the same as the theory predicts based on classical planetary formation, many of them have larger eccentricity and/or small semi-major axis; （4） distribution of known planets in a

关 键 词：天体物理学 太阳系外行星 探测方法 统计特性 

分 类 号：P172[天文地球—天文学]