Rathborne, JM, Longmore, SN, Jackson, JM, Alves, JF, Bally, J, Bastian, N, Contreras, Y, Foster, JB, Garay, G, Kruijssen, JMD, Testi, L and Walsh, AJ (2015) A CLUSTER IN THE MAKING: ALMA REVEALS THE INITIAL CONDITIONS FOR HIGH-MASS CLUSTER FORMATION. ASTROPHYSICAL JOURNAL, 802 (2). ISSN 0004-637X
|
Text
1501.07368v1.pdf - Accepted Version Download (31MB) | Preview |
Abstract
G0.253+0.016 is a molecular clump that appears to be on the verge of forming a high mass, Arches-like cluster. Here we present new ALMA observations of its small-scale (�0.07 pc) 3mm dust continuum and molecular line emission. The data reveal a complex network of emission features, the morphology of which { 3 { ranges from small, compact regions to extended, �lamentary structures that are
seen in both emission and absorption. The dust column density is well traced by molecules with higher excitation energies and critical densities, consistent with a clump that has a denser interior. A statistical analysis supports the idea that turbulence shapes the observed gas structure within G0.253+0.016. We find a clear break in the turbulent power spectrum derived from the optically thin dust continuum emission at a spatial scale of �0.1 pc, which may correspond to the spatial scale at which gravity has overcome the thermal pressure. We suggest that G0.253+0.016 is on the verge of forming a cluster from hierarchical,
�lamentary structures that arise from a highly turbulent medium. Although the stellar distribution within Arches-like clusters is compact, centrally condensed and smooth, the observed gas distribution within G0.253+0.016 is extended, with no high-mass central concentration, and has a complex, hierarchical structure. If this clump gives rise to a high-mass cluster and its stars are formed from this
initially hierarchical gas structure, then the resulting cluster must evolve into a centrally condensed structure via a dynamical process.
Item Type: | Article |
---|---|
Uncontrolled Keywords: | 0201 Astronomical And Space Sciences, 0305 Organic Chemistry, 0306 Physical Chemistry (Incl. Structural) |
Subjects: | Q Science > QB Astronomy Q Science > QC Physics |
Divisions: | Astrophysics Research Institute |
Publisher: | IOP PUBLISHING LTD |
Related URLs: | |
Date Deposited: | 27 May 2015 08:39 |
Last Modified: | 04 Sep 2021 14:20 |
DOI or ID number: | 10.1088/0004-637X/802/2/125 |
URI: | https://researchonline.ljmu.ac.uk/id/eprint/1310 |
View Item |