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oai:www.ideals.illinois.edu:2142/85188 2023-07-11 col_2142_5131 col_2142_14807 com_2142_5130 com_2142_14806 com_2142_8903

Looney, Leslie W. Wang, Shiya 2015-09-25T22:35:39Z 2015-09-25T22:35:39Z 10000-01-01 2008 2008 The main goal of this thesis is to investigate the physical conditions of the star-forming environment in stellar clusters, especially for the formation of low-mass cluster members. Embedded, young, and intermediate-mass stellar clusters around Herbig Ae/Be stars are sampled. Mid- and near-infrared observations identifying young stars and millimeter interferometric observations probing dense molecular gas and dust continuum are presented. These observations are used to reveal the large-scale young stellar population around the vicinity where the sampled clusters form, probe the physical conditions of dense molecular clumps which are capable of forming individual low-mass cluster members, and examine the influence of the most massive star in the cluster on its siblings and natal cluster-forming cloud. This study shows that stars within the cluster tend to seem younger than those outside the cluster, suggesting a higher and continuous star-forming rate within the cluster than outside, or massive stars are initiated later than low-mass stars within the same cloud. A thorough investigation of young stars and dense gas toward the MWC 1080 cluster further suggests a domination of the most massive star in the cluster on both the natal cloud dispersal and its low-mass cluster members. As active outflows and winds from the Herbig Ae/Be stars increase the non-thermal motion in the cloud, low-mass cluster members are formed within denser and more turbulent cores, than isolated low-mass star-forming cores. In addition, the strong gas dispersal from the Herbig Ae/Be stars also helps the removal of the circumstellar material around nearby low-mass stars. This makes these low-mass cluster members appear older. In summary, this thesis provides the observational evidence showing how the most massive star in the cluster affects the formation and evolution of low-mass cluster members and the physical conditions of star formation in the cluster. Made available in DSpace on 2015-09-25T22:35:39Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 3337959.pdf: 2053797 bytes, checksum: 1bc2bf97f2035678daa4ad2445fd6140 (MD5) Previous issue date: 2008 Embargo set by: Seth Robbins for item 86469 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 131 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008. http://hdl.handle.net/2142/85188 (MiAaPQ)AAI3337959 eng Physics, Astronomy and Astrophysics Understanding the Star -Forming Environment in Stellar Clusters text Astronomy Astronomy University of Illinois at Urbana-Champaign Dissertation Ph.D.