The stellar and sub-stellar content of the Trapezium Cluster

四边形星团是研究恒星、原行星盘和亚恒星天体形成和演化的主要目标之一。除了它的接近，它是高质量和低质量恒星的大量和数密度，恒星质量的广泛范围，以及它的极端年轻，使这个星团理想的研究星星和行星形成的各个方面。然而，尽管进行了大量的研究，对梯形星团的全面红外研究-即在空间覆盖（和分辨率）以及灵敏度方面的完整和统一-仍然缺失。在VLT，我们最近对这个重要的星团进行了最广泛的红外研究，覆盖面积为21' x 28'，由36个单独的帧组成。观测可以在极好的视宁度条件下进行（约0.5”），从而分别获得J = 24，H = 20和K = 18的前所未有的极限星等。博士生需要减少和分析这一巨大的数据量，并研究以下问题：-从50兆质量到亚恒星质量的真正初始质量谱的详细形状。在一个被认为经历了触发星星形成的区域，表观年龄的分布很广。作为恒星质量函数的星星形成的时间序列。磁盘人口的大小，由红外线过剩和直接成像见证。结合现有的光学和MIR测光、光谱学和X射线数据，该项目将提供恒星天体物理学中最重要的星团之一的完整概述。目前项目的科学相关性已得到ESO计划委员会的认可。

The Trapezium Cluster is one of the prime targets to study the formation and evolution of stars, proto-planetary disks and sub-stellar objects. Apart from its proximity it is the large number and number density of high- and low-mass stars, the wide range in stellar mass, and its extreme youth that make this cluster ideal to investigate all aspects of star and planet formation. Nevertheless, despite numerous investigations, a comprehensive IR study of the Trapezium cluster - i.e. complete and uniform in terms of spatial coverage (and resolution) as well as in terms of sensitivity - is still missing. At the VLT we have recently performed the most extensive IR study on this important cluster, covering an area of 21’ x 28’ and consisting of 36 individual frames. The observations could be done in superb seeing conditions (~ 0.5”) resulting in unprecedented limiting magnitudes of J = 24, H = 20 and K = 18, respectively. A PhD student is required to reduce and analyze this huge amount of data and to study the following issues:- The detailed shape of a truly initial mass spectrum from 50 M⊙ to sub-stellar masses.- The apparent age spread in a region thought to have undergone triggered star formation.- The time sequence of star formation as a function of stellar mass.- The size of the disk population as witnessed by IR excesses and direct imaging.- Trends of all these aspects with cluster radius.In combination with existing optical and MIR photometry, spectroscopy, and X-ray data this project will provide a complete overview of one of the most important clusters in stellar astrophysics. The scientific relevance of the current project has been acknowledged by the ESO program committee.