Probing the Massive Star-forming Environment: A Multiwavelength Investigation of the Filamentary IRDC G333.73+0.37

Abstract

Abstract We present a multiwavelength study of the filamentary infrared dark cloud (IRDC) G333.73+0.37. The region contains two distinct mid-infrared sources S1 and S2 connected by dark lanes of gas and dust. Cold dust emission from the IRDC is detected at seven wavelength bands, and we have identified 10 high-density clumps in the region. The physical properties of the clumps such as temperature (14.3–22.3 K) and mass (87–1530 M ⊙) are determined by fitting a modified blackbody to the spectral energy distribution of each clump between 160 μm and 1.2 mm. The total mass of the IRDC is estimated to be ∼4700 M ⊙. The molecular line emission toward S1 reveals signatures of protostellar activity. Low-frequency radio emission at 1300 and 610 MHz is detected toward S1 (shell-like) and S2 (compact morphology), confirming the presence of newly formed massive stars in the IRDC. Photometric analysis of near- and mid-infrared point sources unveils the young stellar object population associated with the cloud. Fragmentation analysis indicates that the filament is supercritical. We observe a velocity gradient along the filament, which is likely to be associated with accretion flows within the filament rather than rotation. Based on various age estimates obtained for objects in different evolutionary stages, we attempt to set a limit to the current age of this cloud.