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arXiv · 1103.1126

The Chandra Carina Complex Project View of Trumpler 16

Scott J. Wolk·Patrick S. Broos·Konstantin V. Getman·Eric D. Feigelson·Thomas Preibisch·Leisa K. Townsley·Junfeng Wang·Keivan G. Stassun·Robert R. King·Mark J. McCaughrean·Anthony F. J. Moffat·Hans Zinnecker
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Abstract

Trumpler 16 is a well--known rich star cluster containing the eruptive supergiant $η$ Carinæ and located in the Carina star-forming complex. In the context of the Chandra Carina Complex Project, we study Trumpler 16 using new and archival X-ray data. A revised X-ray source list of the Trumpler 16 region contains 1232 X-ray sources including 1187 likely Carina members. These are matched to 1047 near-infrared counterparts detected by the HAWK-I instrument at the VLT allowing for better selection of cluster members. The cluster is irregular in shape. Although it is roughly circular, there is a high degree of sub-clustering, no noticeable central concentration and an extension to the southeast. The high--mass stars show neither evidence of mass segregation nor evidence of strong differential extinction. The derived power-law slope of the X-ray luminosity function for Trumpler 16 reveals a much steeper function than the Orion Nebula Cluster implying different ratio of solar- to higher-mass stars. We estimate the total Trumpler 16 pre-main sequence population to be > 6500 Class II and Class III X-ray sources. An overall K-excess disk frequency of ~ 8.9% is derived using the X-ray selected sample, although there is some variation among the sub-clusters, especially in the Southeastern extension. X-ray emission is detected from 29 high--mass stars with spectral types between B2 and O3.

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Scott J. Wolk, Patrick S. Broos, Konstantin V. Getman, Eric D. Feigelson, Thomas Preibisch, Leisa K. Townsley, Junfeng Wang, Keivan G. Stassun, Robert R. King, Mark J. McCaughrean, Anthony F. J. Moffat, Hans Zinnecker. 2011-03-06. The Chandra Carina Complex Project View of Trumpler 16. https://doi.org/10.1088/0067-0049%2F194%2F1%2F12

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