Fragmentation of massive cores toward the Galactic Hii region RCW 120 observed with ALMA

Miguel Figueira, Leonardo Bronfman, Annie Zavagno, Fabien Louvet, Nadia Lo, Ricardo Finger, Javier Rodón

High-mass stars are primordial objects in the study of star formation since their feedback has a significant impact on the interstellar medium. The budget of momentum and energy of feedback can change the properties of the new generation of stars which is forming in the molecular cloud. We studied the galactic H ii region RCW 120 both in the far-infrared using the Herschel space telescope and at millimetre wavelength using the ALMA interferometer. Almost all of the massive cores are found in the most massive clump and are fragmented differently. ALMA observations allowed us to characterize this fragmentation in order to see if these massive cores can give rise to high-mass stars. Most of the fragments have mass higher than the thermal Jeans mass, which can be explained by adding turbulence. A few fragments have a mass higher than 8 M_☉ and could potentially be future sites of high-mass star formation. Molecular emissions in the most massive fragment of the most massive core indicate that the protostar is in the hot core phase.

Proceedings of the Polish Astronomical Society, vol. 10, 142-146 (2020)

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