2003/04/30 by R. Salvaterra, Andrea Ferrara, A. Ferrara +2
Physics and Astronomy · #Astrophysics and Star Formation Studies #Gamma-ray bursts and supernovae #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1016/j.newast.2004.06.003
published as New Astron. 10 (2004) 113-120 · 14 pages, 2 figures. Major changes. Accepted for publication in New Astronomy
arxiv created 2004/06/15 · openalex publication_date 2004/06/28 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We show that the explosion of the first supernovae can trigger low-mass star formation via gravitational fragmentation of the supernova-driven gas shell. If the shell mass does not exceed the host galaxy gas mass, all explosions with energies ESN > 1051 erg can lead to shell fragmentation. However, the minimum ambient density required to induce such fragmentation is much larger, n0 > 300 cm-3, for Type II supernovae than for pair-instability ones, which can induce star formation even at lower ambient densities. The typical mass of the unstable fragments is 104-7 Msun; their density is in the range 110-6x107 cm-3. Fragments have a metallicity strictly lower than 10-2.6 Zsun and large values of the gravitational-to-pressure force ratio f ~ 8. Based on these findings, we conclude that the second generation of stars produced by such self-propagating star formation is predominantly constituted by low-mass, long-living, extremely metal-poor (or even metal-free, if mixing is suppressed) stars. We discuss the implications of such results for Pop III star formation scenarios and for the most iron-poor halo star HE0107-5240.