小行星(2572)Annschnell测光数据分析--相接双小行星模型参数测定  

Photometry Analysis of Asteroid(2572)Annschnell——the Contact Binary Asteroids Model

作　　者：黄敬 王晓彬[1,2,3] 窦江培 HUANG Jing;WANG Xiaobin;DOU Jiangpei(Yunnan Observatories,Chinese Academy of Sciences,Kunming 650216,China;University of Chinese Academy of Sciences,Beijing100049,China;Key Laboratory for the Structure and Evolution of Celestial Objects,Chinese Academy of Sciences,Kunming 650216,China;Nanjing Institute of Astronomical Optics&Technology,Chinese Academy of Sciences,Nanjing 210042,China;Key Laboratory of Astronomical Optics&Technology,Chinese Academy of Sciences,Nanjing 210042,China)

机构地区：[1]中国科学院云南天文台,昆明650216 [2]中国科学院大学,北京100049 [3]中国科学院天体结构与演化重点实验室,昆明650216 [4]中国科学院南京天文光学技术研究所,南京210042 [5]中国科学院天文光学技术重点实验室,南京210042

出　　处：《天文学进展》2025年第1期100-113,共14页Progress In Astronomy

基　　金：国家自然科学基金(12373069,U2031210);国家重大科研仪器研制项目(11827804);中国载人航天工程巡天空间望远镜专项(CMS-CSST-2021-B08,CMS-CSST-2021-A11,CMS-CSST-2021-B0)。

摘　　要：太阳系小行星的密度/质量是理解其起源和演化历史的重要参数。小行星密度的测量一直都是具有挑战性的工作,双小行星系统正好提供了测量小天体密度的机会。相接双小行星是一种同步双小行星,其轨道半长轴等于两个小行星(假设为椭球形)的最大半长轴之和。在云南-香港地区宽视场巡天观测数据中发现,小行星(2572)Annschnell的光变曲线展现出典型的相接双小行星光度特征。为此,构建了一套相接双小行星光变曲线反演程序,通过计算得到(2572)Annschnell的两个天体的密度(约为3.15 g/cm^(3)),结果与CV或CK陨石的密度接近,证实该小行星系统应是C族小行星成员。从归一化转动角速度(Ω=0.34)和无量纲系统角动量(H=0.48)推断,该相接双小行星可能由单个小行星经转动裂变形成。The density of small solar system objects is very important for understanding their origin and evolutionary history.However,the determination of the densities of small solar system objects is still a challenging work so far.The binary asteroids provide an oppor-tunity to infer their density.The contact binary asteroid is one type of synchronous binary asteroids,whose orbital semi-major axis is close to the sum of the maximum semi-major axes of two asteroids assuming ellipsoid shapes.Till now,similar systems have been discovered in other small object groups of the solar system,for example,Near-Earth asteroids,Tro-jans,and Kuiper Belt objects.Considering a rubble pile structure of asteroids,the Roche binary asteroid theory can be applied to determine the system parameters including density of asteroids.Asteroid(2572)Annschnell is found possible to be a contact binary asteroid due to special features in its lightcurves obtained by the Yunnan-Hong Kong Wide Field Survey in 2017.A brightness model of the contact binary asteroid is developed,with which the photometric data of(2572)Annschnell are analysed then.The most possible value of density of this binary asteroid is 3.15 g/cm^(3),which is close to that of CV and CK meteorites.Based on the estimate of the normalised rotation rate Ω=0.34 and the dimensionless total angular momentum H=0.48,it is conjectured that this binary asteroid may be formed by the rotational ssion of a spinning asteroid.

关 键 词：太阳系小行星 洛希双小行星 相接双小行星 光度模型 

分 类 号：P141.2[天文地球—天体物理]