Constraints on core‐collapse supernova progenitors from correlations with Hα emission

Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.11). 11/2008; 390(4):1527-1538. DOI: 10.1111/j.1365-2966.2008.13843.x
Source: arXiv


We present observational constraints on the nature of the different core-collapse supernova (SN) types through an investigation of the association of their explosion sites with recent star formation (SF), as traced by Hα+[N ii] line emission. We discuss results on the analysed data of the positions of 168 core-collapse SNe with respect to the Hα emission within their host galaxies.
From our analysis we find that overall the type II progenitor population does not trace the underlying SF. Our results are consistent with a significant fraction of SNII arising from progenitor stars of less than 10 M⊙. We find that the SNe of type Ib show a higher degree of association with H ii regions than those of type II (without accurately tracing the emission), while the type Ic population accurately traces the Hα emission. This implies that the main core-collapse SN types form a sequence of increasing progenitor mass, from the type II, to Ib and finally Ic. We find that the type IIn subclass display a similar degree of association with the line emission to the overall SNII population, implying that at least the majority of these SNe do not arise from the most massive stars. We also find that the small number of SN ‘impostors’ within our sample do not trace the SF of their host galaxies, a result that would not be expected if these events arise from massive luminous blue variable star progenitors.

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Available from: Joseph Anderson, Apr 14, 2014
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    • "We have searched for both classes of emission, and obtained upper limits on the star-formation rates. Hα observations: Hα imaging was obtained with the Liverpool Telescope, and then analyzed using similar methods to those described in detail elsewhere[38]. We have determined an upper limit of 2.02 × 10 −17 erg cm −2 on the Hα flux from the region of SN 2005E. "
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    Nature 05/2010; 465(7296):322-5. DOI:10.1038/nature09056 · 41.46 Impact Factor
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    The Astrophysical Journal 09/2008; 705(2). DOI:10.1088/0004-637X/705/2/1364 · 5.99 Impact Factor
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    ABSTRACT: We use the star formation history map of the Large Magellanic Cloud to study the sites of the eight smallest (and presumably youngest) supernova remnants in the Cloud: SN 1987A, N158A, N49, and N63A (core collapse remnants), 0509-67.5, 0519-69.0, N103B, and DEM L71 (Type Ia remnants). The local star formation histories provide unique insights into the nature of the supernova progenitors, which we compare with the properties of the supernova explosions derived from the remnants themselves and from supernova light echoes. We find that all the core collapse supernovae that we have studied are associated with vigorous star formation in the recent past. Stars more massive than 21.5Msun are very scarce around SNR N49, implying that the magnetar SGR 0526-66 in this SNR was either formed elsewhere or came from a progenitor with a mass well below the 30Msun threshold suggested in the literature. Three of our four Ia SNRs are associated with old, metal poor stellar populations. This includes SNR 0509-67.5, which is known to have been originated by an extremely bright Type Ia event, and yet is located very far away from any sites of recent star formation, in a population with a mean age of 7.9 Gyr. The Type Ia SNR N103B, on the other hand, is associated with recent star formation, and might have had a relatively younger and more massive progenitor with substantial mass loss before the explosion. We discuss these results in the context of our present understanding of core collapse and Type Ia supernova progenitors. Comment: 15 pages, 7 figures, ApJ accepted (replaced with accepted version)
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