Near infrared imaging of the cometary globule CG12

TL;DR

This study uses near-infrared imaging to explore the stellar content and structure of the cometary globule CG12, revealing new members, embedded sources, and detailed associations with IRAS sources, advancing understanding of this star-forming region.

Contribution

The paper provides the first detailed NIR imaging analysis of CG12, identifying new stellar members and clarifying the nature of associated IRAS sources.

Findings

Discovery of new stellar members and candidates in CG12.

Identification of embedded sources with circumstellar disks.

Clarification of IRAS source associations with specific stars.

Abstract

Cometary globule 12 is a relatively little investigated medium- and low mass star forming region 210 pc above the Galactic plane. NIR J, H, and Ks imaging and stellar photometry is used to analyse the stellar content and the structure of CG 12. Several new members and member candidates of the CG 12 stellar cluster were found. The new members include in particular a highly embedded source with a circumstellar disk or shell and a variable star with a circumstellar disk which forms a binary with a previously known A spectral type cluster member. The central source of the known collimated molecular outflow in CG 12 and an associated "hourglass"-shaped object due to reflected light from the source were also detected. HIRES-enhanced IRAS images are used together with SOFI J,H,Ks imaging to study the two associated IRAS point sources, 13546-3941 and 13547-3944. Two new 12 micrometer sources coinciding with NIR excess stars were detected in the direction of IRAS 13546-3941. The IRAS 13547-3944 emission at 12 and 25 micrometers originates in the Herbig AeBe star h4636n and the 60 and 100 micrometer emission from an adjacent cold source.