2006/05/10 by Javier Ballesteros-Paredes, Javier Ballesteros‐Paredes, Ballesteros-Paredes, Javier +2 · 4 citations
Chemistry · Physics and Astronomy · #Astrophysics (astro-ph) #Astrophysics and Star Formation Studies #Atomic and Molecular Physics #FOS: Physical sciences #Molecular Spectroscopy and Structure #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0605268
15 pages, 2 tables. Includes one schematic figure illustrating why the star formation period cannot be a small fraction of the cloud lifetime. Accepted by Revista Mexicana de Astronomia y Astrofisica. Requieres rmaa.cls file (includded)
openalex publication_date 2006/05/10 · arxiv created 2006/10/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We discuss problems with some observational estimates indicating long protostellar core lifetimes and large stellar age spreads in molecular clouds. We also point out some additional observational constraints which suggest that protostellar cores do not have long lifetimes before collapsing. For external galaxies, we argue that the widths of spiral arms does not imply a long star-formation process, since the formation of massive stars will disrupt molecular clouds, move material around, compress it in other regions which produce new star-forming clouds. Thus, it seems unavoidable that this cyclical process will result in an extended period of enhanced star formation, which does not represent the survival time of any individual molecular cloud. We argue that the rapid star formation indicated observationally is also easier to understand theoretically than the traditional scenario of slow quasi-static contraction with ambipolar diffusion.