题  目：Recent Results from the Anglo-Australian Planet Search

报告人：Dr.  Rob  Wittenmyer 
　　　　　 (University  of  New  South  Wales )

摘  要：I discuss two recent planet discoveries from the Anglo-Australian Planet Search. We present 12 years of high-precision radial-velocity data for HD 102365, indicating that this Sun-like star is orbited by a single Neptune-mass planet with a period of 122 days.  Most low-mass planets have been found in multiple systems of 3 to 7 planets; in contrast, HD 102365b appears to orbit its star in splendid isolation. Analysis of the residuals to our Keplerian fit for HD 102365b indicates that there are no other planets with minimum mass above 0.3 M_Jup orbiting within 5 AU and no other "Super Earths" more massive than 10 M_Earth orbiting at periods shorter than 50 days.  We also report the detection of HD 38283b, a gas-giant planet with a period of almost exactly one year (P=363.2 days, m sin i=0.34 M_Jup, e=0.41).  The detection of a planet with a period very close to one year critically relied on year-round observation of this circumpolar star.  This is the first robust detection of an exoplanet with a period near one year.

In addition, I also present a dynamical analysis of the recently-announced planetary system orbiting the eclipsing magnetic white dwarf HU Aquarii.  We show that the proposed planets are extremely unstable.  This suggests that the HU Aquarii planetary system is either more complicated or significantly different to that proposed, or that it is currently undergoing a significant dynamical destabilisation.  We also re-analyse the discovery data and present alternative and more physically plausible system configurations.

时  间：2011年7月8日（星期五）上午 10:30

地  点：（北京西路2号）紫台大楼327教室

欢迎大家积极参与！

　　　　　　　　　　　　　  紫金山天文台学术委员会学术交流工作委员会