EMBEDDED YOUNG STELLAR POPULATION IN THE GALACTIC MOLECULAR CLOUD ASSOCIATED WITH IRAS 18236-1205

We study the molecular cloud associated with the ultracompact HII region IRAS 18236-1205 to identify the young stellar objects (YSOs) embedded in the cloud. The 13CO intensity contours from the Galactic Ring Survey (GRS) data were used to dene the geometry of the cloud, and the search for YSOs was c...

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Detalles Bibliográficos
Autores: R. Retes, A. Luna, Y. D. Mayya, L. Carrasco
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:México
Institución:Instituto Nacional de Astrofísica, Óptica y Electrónica
Repositorio:Redalyc-INAOE
OAI Identifier:oai:redalyc.org:57115687027
Acceso en línea:https://www.redalyc.org/articulo.oa?id=57115687027
Access Level:acceso abierto
Palabra clave:Física, Astronomía y Matemáticas
stars: Pre
HII regions
ISM: clouds
main sequence
stars: formation
Descripción
Sumario:We study the molecular cloud associated with the ultracompact HII region IRAS 18236-1205 to identify the young stellar objects (YSOs) embedded in the cloud. The 13CO intensity contours from the Galactic Ring Survey (GRS) data were used to dene the geometry of the cloud, and the search for YSOs was carried out based on the NIR 2MASS photometric data. The search yielded two objects inside the IRAS beam, both with counterparts with the recently available Spitzer sources. The NIR to FIR Spectral Energy Distributions of these two sources were modeled as the sum of uxes of an embedded hot star and a warm dust envelope. From the resulting ts, we infer spectral types of B0.5V and B8V for the two YSOs, both experiencing visual extinctions of - 20 mag, with the former source responsible for almost all the observed emission in the IRAS 60 and 100 Gm bands. A third stellar object inside the IRAS beam was identied only on the Spitzer images, and is associated with an arc at 4.5 m, which we propose as a low-mass star with an outflow.