Study of the 13CO/C18O abundance ratio towards the filamentary infrared dark cloud IRDC 34.43+0.24

ORTEGA, M. E.; PARON, S.; AREAL, M. B.; DUVIDOVICH L.

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF AUSTRALIA

CSIRO PUBLISHING

Lugar: Collingwood; Año: 2019

1323-3580

Nowadays there are several observational studies about the13CO/C18O abundance ratio (X13/18) towardsnearby molecular clouds. These works give observational support to the C18O selective photodissociationdue to the interaction between the far ultraviolet (FUV) radiation and the molecular gas. It is necessaryto increase the sample of molecular clouds located at different distances and affected in different waysby nearby or embedded HII regions and OB associations to study the selective photodissociation. Using12CO,13CO, and C18O J=1?0 data obtained from the FOREST unbiased Galactic plane imaging surveyperformed with the Nobeyama 45 m telescope, we analyze the filamentary infrared dark cloud IRDC34.43+0.24 located at the distance of about 3.9 kpc. This IRDC is related to several HII regions andyoung stellar objects. Assuming local thermodynamic equilibrium we obtain:0.8×1016