标题： 高度动态演化的中间年龄疏散星团 显示英文标题

标题： Highly dynamically evolved intermediate-age open clusters

摘要： 我们对七个已列入星表的疏散星团进行了全面的UBVRI和Washington CT1T2测光分析，它们分别是：Ruprecht 3、9、37、74、150、ESO 324-15和436-2。 结合双子星巡天（2MASS）测光数据和Gaia天文学测量数据中的较亮恒星信息，多波段测光数据集被用于估算这些星团的结构参数和基本天体物理特性。 我们发现Ruprecht 3和ESO 436-2并未显示出一致的物理系统证据。 其余研究对象为中间年龄（9.0 < log(t 年-1) < 9.6）、相对较小尺寸（r_cls ~ 0.4 - 1.3 pc）且距离太阳0.6到2.9千秒差距的疏散星团。 我们分析了核心半径、半质量半径、潮汐半径以及Jacoby半径之间的关系，以及半质量松弛时间，得出结论：所研究的星团处于演化的动力学阶段。 通过将观测到的星团恒星质量相加得到的星团质量约为类似年龄但距离太阳小于2千秒差距的疏散星团质量的10%-15%。 我们发现星团恒星占据的体积与潮汐填充的星团相当。 显示英文摘要

摘要： We present a comprehensive UBVRI and Washington CT1T2 photometric analysis of seven catalogued open clusters, namely: Ruprecht 3, 9, 37, 74, 150, ESO 324-15 and 436-2. The multi-band photometric data sets in combination with 2MASS photometry and Gaia astrometry for the brighter stars were used to estimate their structural parameters and fundamental astrophysical properties. We found that Ruprecht 3 and ESO 436-2 do not show self-consistent evidence of being physical systems. The remained studied objects are open clusters of intermediate-age (9.0 < log(t yr-1) < 9.6), of relatively small size (r_cls ~ 0.4 - 1.3 pc) and placed between 0.6 and 2.9 kpc from the Sun. We analized the relationships between core, half-mass, tidal and Jacoby radii as well as half-mass relaxation times to conclude that the studied clusters are in an evolved dynamical stage. The cluster masses obtained by summing those of the observed cluster stars resulted to be ~ 10-15 per cent of the masses of open clusters of similar age located closer than 2 kpc from the Sun. We found that cluster stars occupy volumes as large as those for tidally filled clusters.