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dc.contributor.authorCamargo, Denilso da Silvapt_BR
dc.contributor.authorBica, Eduardo Luiz Damianipt_BR
dc.contributor.authorBonatto, Charles Josept_BR
dc.date.accessioned2017-11-25T02:26:57Zpt_BR
dc.date.issued2016pt_BR
dc.identifier.issn0004-6361pt_BR
dc.identifier.urihttp://hdl.handle.net/10183/170578pt_BR
dc.description.abstractContext. Until recently it was thought that high Galactic latitude clouds were a non-star-forming ensemble. However, in a previous study we reported the discovery of two embedded clusters (ECs) far away from the Galactic plane ( 5 kpc). In our recent star cluster catalogue we provided additional high and intermediate latitude cluster candidates. Aims. This work aims to clarify whether our previous detection of star clusters far away from the disc represents just an episodic event or whether star cluster formation is currently a systematic phenomenon in the Galactic halo. We analyse the nature of four clusters found in our recent catalogue and report the discovery of three new ECs each with an unusually high latitude and distance from the Galactic disc midplane. Methods. The analysis is based on 2MASS and WISE colour-magnitude diagrams (CMDs), and stellar radial density profiles (RDPs). The CMDs are built by applying a field-star decontamination procedure, which uncovers the cluster’s intrinsic CMD morphology. Results. All of these clusters are younger than 5 Myr. The high-latitude ECs C 932, C 934, and C 939 appear to be related to a cloud complex about 5 kpc below the Galactic disc, under the Local arm. The other clusters are above the disc, C 1074 and C 1100 with a vertical distance of 3 kpc, C 1099 with 2 kpc, and C 1101 with 1:8 kpc Conclusions. According to the derived parameters ECs located below and above the disc occur, which gives evidence of widespread star cluster formation throughout the Galactic halo. This study therefore represents a paradigm shift, by demonstrating that a sterile halo must now be understood as a host for ongoing star formation. The origin and fate of these ECs remain open. There are two possibilities for their origin, Galactic fountains or infall. The discovery of ECs far from the disc suggests that the Galactic halo is more actively forming stars than previously thought. Furthermore, since most ECs do not survive the infant mortality, stars may be raining from the halo into the disc, and/or the halo may be harbouring generations of stars formed in clusters like those detected in our survey.en
dc.format.mimetypeapplication/pdf
dc.language.isoengpt_BR
dc.relation.ispartofAstronomy and astrophysics. Les Ulis. Vol. 593 (Sept. 2016), A95, 9 p.pt_BR
dc.rightsOpen Accessen
dc.subjectISM: cloudsen
dc.subjectHalospt_BR
dc.subjectAglomerados abertos e associaçõespt_BR
dc.subjectGalaxy: haloen
dc.subjectOpen clusters and associations: generalen
dc.subjectFormacao de estrelaspt_BR
dc.titleNew detections of embedded clusters in the Galactic halopt_BR
dc.typeArtigo de periódicopt_BR
dc.identifier.nrb001050890pt_BR
dc.type.originEstrangeiropt_BR


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