Refined classification for Orion A protostars

DOI

In the list of young stellar objects (YSOs) compiled by Megeath et al. (2012, J/AJ/144/192) for the Orion A molecular cloud, only 44 out of 1208 sources found projected onto low extinction (A_K_<0.8mag) gas are identified as protostars. These objects are puzzling because protostars are not typically expected to be associated with extended low extinction material. Here, we use high resolution extinction maps generated from Herschel data, optical/infrared and Spitzer Space Telescope photometry and spectroscopy of the low extinction protostellar candidate sources to determine if they are likely true protostellar sources or contaminants. Out of 44 candidate objects, we determine that 10 sources are likely protostars, with the rest being more evolved YSOs (18), galaxies (4), false detections of nebulosity and cloud edges (9), or real sources for which more data are required to ascertain their nature (3). We find none of the confirmed protostars to be associated with recognizable dense cores and we briefly discuss possible origins for these orphaned objects.

Cone search capability for table J/ApJ/825/91/table1 (Low Ak source classification)

Identifier
DOI http://doi.org/10.26093/cds/vizier.18250091
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/825/91
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/825/91
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/825/91
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/825/91
Provenance
Creator Lewis J.A.; Lada C.J.
Publisher CDS
Publication Year 2016
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Interstellar medium; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy