ALMA-IMF XVII - Census and lifetime of high-mass prestellar cores in 14 massive protoclusters

• DOI: 10.48550/arxiv.2502.09426
• Publication Date: 2025-02-13
• Authors: M. Valeille-Manet; Sylvain Bontemps; T. Csengeri; T. Nony; F. Motte; Amelia M. Stutz; A. Gusdorf; Adam Ginsburg; Roberto Galván-Ma...; P. Sanhueza; M. Bonfand; N. Brouillet; P. Dell'Ova; F. Louvet; N. Cunningham; Manuel Fernández-...; F. Herpin; F. Wyrowski; R. H. Álvarez-Gut...; M. Armante; Andrés E. Guzmán; N. Kessler; Atanu Koley; J. Salinas; T. Yoo; L. Bronfman; N. Le Nestour
• Keywords: Astrophysics - Solar and Stellar Astrophysics; Astrophysics of Galaxies (astro-ph.GA); FOS: Physical sciences; Astrophysics - Astrophysics of Galaxies; Solar and Stellar Astrophysics (astro-ph.SR)

High-mass prestellar cores are extremely rare. The search for such objects has long been hindered by small sample sizes, leading to large uncertainties in their lifetimes and the conditions which high-mass stars ($> 8\,M_{\odot}$) form. We leverage ($\sim 580$ cores) detected ALMA-IMF survey identify both protostellar estimate relative lifetimes. use CO SiO outflows introduce a new automated method based on aperture line emission background subtraction systematically detect associated with each of 141 most massive cores. Massive that do not drive an outflow either tracer classified as prestellar. Our enables efficient detection performance comparable more traditional techniques. 30 likely $M > 8\,M_{\odot}$, including 12 16\,M_{\odot}$, best candidates star precursors. Most these reside crowded central regions protoclusters, where expected Using prestellar-to-protostellar core ratios 300 kyr lifetime, we 120 240 $8\,M_{\odot} < M 16\,M_{\odot}$ 50 100 $30\,M_{\odot} 55\,M_{\odot}$. These timescales, depend different mass reservoir evolution scenarios, significantly exceed 4 15 free-fall time cores, suggesting persist 10 times. This indicates collapse is slowed turbulence, magnetic fields, or rotation at below observed scale.