Context: The Ara OB1a association is a nearby complex in the fourth Galactic quadrant where a number of young/embedded star clusters are projected close to more evolved, intermediate age clusters. It is also rich in interstellar matter, and contains evidence of the interplay between massive stars and their surrounding medium, such as the rim HII region NGC 6188. Aims: We provide robust estimates of the fundamental parameters (age and distance) of the two most prominent stellar clusters, NGC 6167 and NGC 6193, that may be used as a basis for studing the star formation history of the region. Methods: The study is based on a photometric optical survey (UBVIHa) of NGC 6167 and NGC 6193 and their nearby field, complemented with public data from 2MASS-VVV, UCAC3, and IRAC-Spitzer in this region. Results: We produce a uniform photometric catalogue and estimate more robustly the fundamental parameters of NGC 6167 and NGC 6193, in addition to the IRAS 16375-4854 source. As a consequence, all of them are located at approximately the same distance from the Sun in the Sagittarius-Carina Galactic arm. However, the ages we estimate differ widely: NGC 6167 is found to be an intermediate-age cluster (20-30 Myr), NGC 6193 a very young one (1-5 Myr) with PMS, H? emitters and class II objects, and the IRAS 16375-4854 source is the youngest of the three containing several YSOs. Conclusions: These results support a picture in which Ara OB1a is a region where star formation has proceeded for several tens of Myr until the present. The difference in the ages of the different stellar groups can be interpreted as a consequence of a triggered star formation process. In the specific case of NGC 6193, we find evidence of possible non-coeval star formation.
The evolution of velocity dispersion in the Sco-Cen OB association
Astronomical Institute of the Czech Academy of Sciences（捷克科学院天文研究所）；Universität zu Köln（科隆大学）；University of Vienna（维也纳大学）；Center for Astrophysics | Harvard & Smithsonian（哈佛-史密森天体物理中心）；Univ. de Barcelona (UB)（巴塞罗那大学）；Institut de Ciències del Cosmos (ICCUB)（宇宙科学研究所）
IAU Commission 37 "Star Clusters and Associations" Legacy report
人们普遍认为，恒星不是孤立形成的，而是分子云分裂的结果，这反过来又导致了恒星团簇形成。随着时间的推移，星系团溶解或被分子云或潮汐剥离的相互作用所破坏，它们的成员成为一般场人口的一部分。因此，星团是星系的基本组成部分。反过来，从年轻的星协和疏散星团到年老的球状星团，星团的数量是其母星系形成、聚集和演化历史的有力线索。虽然它们的重要性已经被认识了几十年，但这一领域的重大进展只是在最近几年才成为可能，无论是对银河系还是河外星系团。星团是恒星天体物理和演化的观测基础，是研究星系结构的重要示踪物，是独特的恒星动力学环境。恒星形成、恒星结构、恒星演化和恒星核合成等方面的研究都从这些系统的研究中获益匪浅。此外，基本量，如初始质量函数可以成功地从建模的H-R图或集成的速度结构，分别解决和未解决的集群和集群人口。因此，星团研究横跨银河系和河外天体物理学领域，同时也极大地影响了我们对致密环境中恒星形成过程的详细理解。本报告重点介绍了IAU第37委员会（37 Committee：Star clusters and associations）在过去十年中所涵盖的主要领域的科学成果。
JWST Reveals a Galaxy-Wide Association of Red Supergiants with OB Stars in NGC 5584
School of Physics and Astronomy, China West Normal University（西华师范大学物理与天文学学院）；School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院）；Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University（北京师范大学前沿天文与天体物理研究所）；CAS Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台光学天文重点实验室）
