2009/08/12 by Paolo A. Mazzali, Jinsong Deng, Mario Hamuy +1 · 2 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #CCD and CMOS Imaging Sensors #Gamma-ray bursts and supernovae #Hydrogen #Light curve #Near-Earth supernova #Pair-instability supernova #Spectral line #Supernova #Type II supernova #astro-ph.HE #astro-ph.SR
paper · pdf · doi:10.1088/0004-637x/703/2/1624
29 pages, 7 figures, in press in the ApJ
arxiv created 2009/08/12 · openalex publication_date 2009/09/12 · arxiv updated 2015/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Models for the spectra and the light curve (LC), in the photospheric as well as in the late nebular phase, are used to infer the properties of the very radio-bright, broad-lined type IIb supernova (SN) 2003bg. Consistent fits to the LC and the spectral evolution are obtained with an explosion that ejected ≈4 M ☉ of material with a kinetic energy of ≈5 × 10 51 erg. A thin layer of hydrogen, comprising ∼0.05 M ☉ , is inferred to be present in the ejecta at the highest velocities ( v ≳ 9000 km s −1 ), while a thicker helium layer, comprising ≈1.25 M ☉ , was ejected at velocities between 6500 and 9000 km s −1 . At lower velocities, heavier elements are present, including ∼0.2 M ☉ of 56 Ni that shape the LC and the late-time nebular spectra. These values suggest that the progenitor star had a mass of ≈20–25 M ☉ , (comparable to, but maybe somewhat smaller than that of the progenitor of the X-ray flashes/SN 2008D). The rather broad-lined early spectra are the result of the presence of a small amount of material (≈0.03 M ☉ ) at velocities >0.1 c , which carries ≈10% of the explosion kinetic energy. No clear signatures of a highly aspherical explosion are detected.