利用红团簇巨星测定大样本银河系疏散星团距离

Based on 2MASS,WISE all-sky infrared star catalog, perform absolute magnitude calibration for pop-I red clump giants by selecting several tens of well studied open clusters with high precision photometric & spectral data and reliable distance, reddening, age and metallicity parameters. Make systematic investigation on CMD s of each Galactic open clusters, identifying red clumps members on these CMDs, then determine the distances of about a thousand open clusters using the red clump giants as the standard candle, resulting a new open cluster catalog with homogeneous, independent and high precision distance parameter, introducing important progresses in probing astrophysical properties of open clusters and aslo establishing firm foundation for studies on Galactic structure & evolution traced by open clusters.

基于2MASS、WISE等红外全天星表，选取具备高精度测光与高分辨率光谱观测结果、已有可靠成员判定及丰度、年龄、距离和红化测定值的数十个"标准"星团对星族I红团簇巨星绝对星等进行校准测定；对已知银河系疏散星团的红外波段颜色-星等图(CMD)作系统考察，逐个证认这些星团CMD上的红团簇巨星成分；基于红团簇巨星近红外波段绝对星等(作为标准烛光)的测定结果，系统地测定上千个疏散星团的距离，构建独立、均匀一致的高精度疏散星团距离参数表；取得疏散星团天体物理性质研究的重要进展，为利用星团作探针研究银河系结构和演化奠定坚实的基础。

开展了M星巨星的辨识及最大样本的汇集，按计划初步完成银河系疏散星团红团簇巨星的证认；对已知银河系疏散星团的红外波段颜色-星等图(CMD)作系统考察，逐个证认这些星团CMD上的红团簇巨星成分，利用视向速度数据对疏散星团红团簇星的成员性作有效约束；确立了星团性质测定的方法与归算流程，对星团年龄、距离和红化等物理参数作等年龄线拟合，为利用疏散星团进行银盘性质统计研究奠定基础。对距离太阳约3kpc内数百个疏散星团物理性质的精细测量正在进行之中。