2004/08/25 by Masao Mori, Masayuki Umemura, Andrea Ferrara · 2 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy and Astrophysical Research #Chemical evolution #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Gamma-ray bursts and supernovae #Interstellar medium #Luminosity #Mixing (physics) #Supernova #astro-ph
paper · pdf · doi:10.1086/425255
published as Astrophys.J. 613 (2004) L97-L100 · 4 pages, 2 figures, accepted fot publicatin in ApJL
arxiv created 2004/08/25 · openalex publication_date 2004/08/31 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We consider a forming galaxy undergoing multitudinous supernova (SN) explosions as a possible model of Lyα blobs (LABs). For this purpose, an ultra-high-resolution hydrodynamic simulation is performed using 1024 3 grid points, where SN remnants are resolved with sufficient accuracy. It is found that multiple SN explosions produce kiloparsec-size expanding hot bubbles, which drive cool, dense shells by strong shock. The colliding high-density cooling shells radiate intensive Lyα emission, resulting in a high Lyα luminosity of ~10 43 ergs s -1 , comparable to the observed level in LABs. Also, recently discovered bubbly features in some LABs are quite similar to the structure predicted in the present simulation. Furthermore, the result demonstrates that LABs are representative of evolving primordial galaxies; they could hold direct information on the early chemical enrichment of galaxies, contrary to present-day galaxies that have undergone intense recycling of interstellar matter, thus erasing most of the early chemical history. It turns out that the metal mixing proceeds in a very inhomogeneous fashion, so that there appears a large spread of metallicity, that is, [Fe/H] ≈ 0 to - 5 or [O/H] ≈ 1 to - 4. Hence, the early galactic chemical evolution may have proceeded in a different manner from that hitherto considered in one-zone models.