dc.contributor.author | Getman, KV | |
dc.contributor.author | Kuhn, MA | |
dc.contributor.author | Feigelson, ED | |
dc.contributor.author | Broos, PS | |
dc.contributor.author | Bate, MR | |
dc.contributor.author | Garmire, GP | |
dc.date.accessioned | 2018-05-17T08:03:28Z | |
dc.date.issued | 2018-02-22 | |
dc.description.abstract | The SFiNCs (Star Formation in Nearby Clouds) project is an X-ray/infrared study of the young stellar populations in 22 star-forming regions with distances
≲1
kpc designed to extend our earlier MYStIX (Massive Young Star-Forming Complex Study in Infrared and X-ray) survey of more distant clusters. Our central goal is to give empirical constraints on cluster formation mechanisms. Using parametric mixture models applied homogeneously to the catalogue of SFiNCs young stars, we identify 52 SFiNCs clusters and 19 unclustered stellar structures. The procedure gives cluster properties including location, population, morphology, association with molecular clouds, absorption, age (AgeJX), and infrared spectral energy distribution (SED) slope. Absorption, SED slope, and AgeJX are age indicators. SFiNCs clusters are examined individually, and collectively with MYStIX clusters, to give the following results. (1) SFiNCs is dominated by smaller, younger, and more heavily obscured clusters than MYStIX. (2) SFiNCs cloud-associated clusters have the high ellipticities aligned with their host molecular filaments indicating morphology inherited from their parental clouds. (3) The effect of cluster expansion is evident from the radius–age, radius–absorption, and radius–SED correlations. Core radii increase dramatically from ∼0.08 to ∼0.9 pc over the age range 1–3.5 Myr. Inferred gas removal time-scales are longer than 1 Myr. (4) Rich, spatially distributed stellar populations are present in SFiNCs clouds representing early generations of star formation. An appendix compares the performance of the mixture models and non-parametric minimum spanning tree to identify clusters. This work is a foundation for future SFiNCs/MYStIX studies including disc longevity, age gradients, and dynamical modelling. | en_GB |
dc.description.sponsorship | The MYStIX project is now supported by the Chandra archive grant AR7-18002X. The SFiNCs project is supported at Penn State by NASA grant NNX15AF42G, Chandra GO grant SAO AR5- 16001X,
Chandra GO grant GO2-13012X, Chandra GO grant GO3-14004X, Chandra GO grant GO4-15013X, and the Chandra ACIS Team contract SV474018 (G. Garmire and L. Townsley,
Principal Investigators), issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of NASA under contract NAS8-03060. | en_GB |
dc.identifier.citation | Vol. 477 (1), pp. 298 - 324 | en_GB |
dc.identifier.doi | 10.1093/mnras/sty473 | |
dc.identifier.uri | http://hdl.handle.net/10871/32888 | |
dc.language.iso | en | en_GB |
dc.publisher | Oxford University Press | en_GB |
dc.relation.source | The Guaranteed Time Observations (GTO) data used here were selected by the ACIS
Instrument Principal Investigator, Gordon P. Garmire, of the Huntingdon
Institute for X-ray Astronomy, LLC, which is under contract
to the Smithsonian Astrophysical Observatory; Contract SV2-
82024. This research made use of data products from the Chandra
Data Archive and the Spitzer Space Telescope, which is operated
by the Jet Propulsion Laboratory (California Institute of Technology)
under a contract with NASA. This research used data products
from the Two Micron All-Sky Survey, which is a joint project of
the University of Massachusetts and the Infrared Processing and
Analysis Center/California Institute of Technology, funded by the
National Aeronautics and Space Administration and the National
Science Foundation. This research has also made use of NASA’s
Astrophysics Data System Bibliographic Services and SAOIMAGE DS9
software developed by Smithsonian Astrophysical Observatory. | en_GB |
dc.rights | © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society
Supplement | en_GB |
dc.subject | stars: early-type | en_GB |
dc.subject | stars: formation | en_GB |
dc.subject | stars: pre-main-sequence | en_GB |
dc.subject | open clusters and associations: general | en_GB |
dc.subject | infrared: stars | en_GB |
dc.subject | X-rays: stars | en_GB |
dc.title | Young star clusters in nearby molecular clouds | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2018-05-17T08:03:28Z | |
dc.identifier.issn | 0035-8711 | |
dc.description | This is the final version of the article. Available from Oxford University Press via the DOI in this record. | en_GB |
dc.identifier.journal | Monthly Notices of the Royal Astronomical Society | en_GB |