UKIRT NIR and Spitzer MIR phot. in NGC 6822

DOI

The nearby (~500kpc) metal-poor ([Fe/H]~-1.2; Z~30%Z_{sun}_) star-forming galaxy NGC 6822 has a metallicity similar to systems at the epoch of peak star formation. Through identification and study of dusty and dust-producing stars, it is therefore a useful laboratory to shed light on the dust life cycle in the early universe. We present a catalog of sources combining near- and mid-IR photometry from the United Kingdom Infrared Telescope (J, H, and K) and the Spitzer Space Telescope (IRAC 3.6, 4.5, 5.8, and 8.0{mu}m and MIPS 24{mu}m). This catalog is employed to identify dusty and evolved stars in NGC 6822 utilizing three color-magnitude diagrams (CMDs). With diagnostic CMDs covering a wavelength range spanning the near- and mid-IR, we develop color cuts using kernel density estimate (KDE) techniques to identify dust-producing evolved stars, including red supergiant (RSG) and thermally pulsing asymptotic giant branch (TP-AGB) star candidates. In total, we report 1292 RSG candidates, 1050 oxygen-rich AGB star candidates, and 560 carbon-rich AGB star candidates with high confidence in NGC 6822. Our analysis of the AGB stars suggests a robust population inhabiting the central stellar bar of the galaxy, with a measured global stellar metallicity of [Fe/H]=-1.286+/-0.095, consistent with previous studies. In addition, we identify 277 young stellar object (YSO) candidates. The detection of a large number of YSO candidates within a centrally located, compact cluster reveals the existence of an embedded, high-mass star formation region that has eluded previous detailed study. Spitzer I appears to be younger and more active than the other prominent star-forming regions in the galaxy.

Cone search capability for table J/ApJ/892/91/table1 (The master catalog)

Identifier
DOI http://doi.org/10.26093/cds/vizier.18920091
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/892/91
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/892/91
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/892/91
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/892/91
Provenance
Creator Hirschauer A.S.; Gray L.; Meixner M.; Jones O.C.; Srinivasan S.,Boyer M.L.; Sargent B.A.
Publisher CDS
Publication Year 2021
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; Cosmology; Galactic and extragalactic Astronomy; Interstellar medium; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy