A multiwavelength study of the massive star-forming region IRAS 06055+2039 (RAFGL 5179)

Abstract

Aims: We present a multiwavelength study of the massive star-forming region associated with IRAS 06055+2039. Methods: Narrow-band near-infrared (NIR) observations were carried out with UKIRT-UFTI in molecular hydrogen and Br lines to trace the shocked and ionized gases, respectively. We have used 2MASS JHK_s data to study the nature of the embedded cluster associated with IRAS 06055+2039. The radio emission from the ionized gas was mapped at 610 and 1280 MHz using the Giant Metrewave Radio Telescope (GMRT), India. Emission from warm dust and the unidentified infrared bands (UIBs) was estimated using the mid-infrared (8-21 µm) data from the MSX survey. Submillimetre emission from the cold dust at 450 and 850 µm was studied using JCMT-SCUBA. Results: For the infrared cluster associated with IRAS 06055+2039, we obtain a power-law slope of 0.43 ± 0.09 for the K_s-band luminosity function (KLF), which is in good agreement with other young embedded clusters. We estimate an age of 2-3 Myr for this cluster. Apart from the diffuse emission, the high-resolution 1280 MHz map also shows the presence of several discrete sources that possibly represent high-density clumps. The morphology of shocked molecular hydrogen forms an arc towards the N-E of the central IRAS point source and envelopes the radio emission. Submillimetre emission shows the presence of a dense cloud core that is probably at an earlier evolutionary stage compared to the ionized region with shocked molecular gas lying between the two. The total mass of the cloud is estimated to be ~7000-9000 M from the submillimetre emission at 450 and 850µm. Conclusions: The multiwavelength study of this star-forming complex reveals an interesting scenario where regions are at different stages in the evolution of star formation.