Fragmentation of the High-mass "Starless'' Core G10.21-0.31: a Coherent Evolutionary Picture for Star Formation

TL;DR

This study uses high-resolution ALMA and SMA observations to analyze the internal fragmentation and evolutionary stages of the high-mass starless core G10.21-0.31, providing insights into the process of high-mass star formation.

Contribution

It presents the first detailed internal structure and evolutionary analysis of G10.21-0.31, revealing turbulent fragmentation and the absence of high-mass prestellar cores, supporting a dynamic mass-growth star formation model.

Findings

Identification of three cores with masses 11-18 M_sun

Detection of outflows, temperature variations, and deuteration levels

Absence of high-mass prestellar cores

Abstract

G10.21-0.31 is a 70 $\mu$m-dark high-mass starless core ($M>300$ $\mathrm{M_{\odot}}$ within $r<0.15$ pc) identified in $Spitzer$, $Herschel$, and APEX continuum surveys, and is believed to harbor the initial stages of high-mass star formation. We present ALMA and SMA observations to resolve the internal structure of this promising high-mass starless core. Sensitive high-resolution ALMA 1.3 mm dust continuum emission reveals three cores of mass ranging 11-18 $\mathrm{M_{\odot}}$, characterized by a turbulent fragmentation. Core 1, 2, and 3 represent a coherent evolution at three different evolutionary stages, characterized by outflows (CO, SiO), gas temperature ($\mathrm{H_2CO}$), and deuteration ($\mathrm{N_2D^+/N_2H^+}$). We confirm the potential to form high-mass stars in G10.21 and explore the evolution path of high-mass star formation. Yet, no high-mass prestellar core is present in G10.21. This suggests a dynamical star formation where cores grow in mass over time.