Abstract
Supernovae connected with long-duration γ-ray bursts1,2,3 (GRBs) are hyper-energetic explosions resulting from the collapse of very massive stars (∼40 M⊙, where M⊙ is the mass of the Sun) stripped of their outer hydrogen and helium envelopes4,5,6,7. A very massive progenitor, collapsing to a black hole, was thought to be a requirement for the launch of a GRB8. Here we report the results of modelling the spectra and light curve of SN 2006aj (ref. 9), which demonstrate that the supernova had a much smaller explosion energy and ejected much less mass than the other GRB–supernovae, suggesting that it was produced by a star whose initial mass was only ∼20 M⊙. A star of this mass is expected to form a neutron star rather than a black hole when its core collapses. The smaller explosion energy of SN 2006aj is matched by the weakness and softness10 of GRB 060218 (an X-ray flash), and the weakness of the radio flux of the supernova11. Our results indicate that the supernova–GRB connection extends to a much broader range of stellar masses than previously thought, possibly involving different physical mechanisms: a ‘collapsar’ (ref. 8) for the more massive stars collapsing to a black hole, and magnetic activity of the nascent neutron star12 for the less massive stars.
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References
Galama, T. J. et al. An unusual supernova in the error box of the gamma-ray burst of 25 April 1998. Nature 395, 670–672 (1998)
Stanek, K. Z. et al. Spectroscopic discovery of the supernova 2003dh associated with GRB 030329. Astrophys. J. 591, L17–L20 (2003)
Malesani, J. et al. SN 2003lw and GRB 031203: a bright supernova for a faint gamma-ray burst. Astrophys. J. 609, L5–L8 (2004)
Iwamoto, K. et al. A hypernova model for the supernova associated with the gamma-ray burst of 25 April 1998. Nature 395, 672–674 (1998)
Mazzali, P. A. et al. The type Ic hypernova SN 2003dh/GRB 030329. Astrophys. J. 599, L95–L98 (2003)
Deng, J. et al. On the light curve and spectrum of SN 2003dh separated from the optical afterglow of GRB 030329. Astrophys. J. 624, 898–905 (2005)
Mazzali, P. A. et al. Models for the type Ic hypernova SN 2003lw associated with GRB 031203. Astrophys. J. 645, 1323–1330 (2006)
MacFadyen, A. E. & Woosley, S. E. Collapsars: gamma-ray bursts and explosions in ‘Failed Supernovae’. Astrophys. J. 524, 262–289 (1999)
Pian, E. et al. An optical supernova associated with the X-ray flash XRF 060218. Nature doi:10.1038/nature05082 (this issue)
Campana, S. et al. The association of GRB 060218 with a supernova and the evolution of the shock wave. Nature doi:10.1038/nature04892 (this issue)
Soderberg, A. M. et al. Relativistic ejecta from X-ray flash XRF 060218 and the rate of cosmic explosions. Nature doi:10.1038/nature05087 (this issue)
Thompson, T. A., Chang, P. & Quataert, E. Magnetar spin-down, hyperenergetic supernovae, and gamma-ray bursts. Astrophys. J. 611, 380–393 (2004)
Mazzali, P. A. et al. The type Ic hypernova SN 2002ap. Astrophys. J. 572, L61–L64 (2002)
Foley, R. J. et al. Optical photometry and spectroscopy of the SN 1998bw-like type Ic supernova 2002ap. Publ. Astron. Soc. Pacif. 115, 1220–1235 (2003)
Arnett, W. D. Type I supernovae. I—Analytic solutions for the early part of the light curve. Astrophys. J. 253, 785–797 (1982)
Maeda, K. et al. Explosive nucleosynthesis in aspherical hypernova explosions and late-time spectra of SN 1998bw. Astrophys. J. 565, 405–412 (2002)
Mazzali, P. A. et al. An asymmetric energetic type Ic supernova viewed off-axis, and a link to gamma ray bursts. Science 308, 1284–1287 (2005)
Tominaga, N. et al. The unique type Ib supernova 2005bf: a WN star explosion model for peculiar light curves and spectra. Astrophys. J. 633, L97–L100 (2005)
Nomoto, K. et al. A carbon–oxygen star as progenitor of the type-Ic supernova 1994I. Nature 371, 227–229 (1994)
Hamuy, M. Observed and physical properties of core-collapse supernovae. Astrophys. J. 582, 905–914 (2003)
Fynbo, J. P. U. et al. On the afterglow of the X-ray flash of 2003 July 23: photometric evidence for an off-axis gamma-ray burst with an associated supernova? Astrophys. J. 609, 962–971 (2004)
Tominaga, N. et al. Supernova light-curve models for the bump in the optical counterpart of X-ray flash 030723. Astrophys. J. 612, L105–L108 (2004)
Nakamura, T. A model for non high energy gamma ray bursts and sources of ultra high energy cosmic rays. Prog. Theor. Phys. 100, 921–929 (1998)
Nomoto, K. et al. Hypernovae and gamma-ray bursts. Astrophys. Space Sci. 298, 81–86 (2005)
Nomoto, K., Iwamoto, K. & Suzuki, T. The evolution and explosion of massive binary stars and Type Ib-Ic-IIb-IIL supernovae. Phys. Rep. 256, 173–191 (1995)
Fryer, C., Woosley, S. E. & Hartmann, D. H. Formation rates of black hole accretion disk gamma-ray bursts. Astrophys. J. 526, 152–177 (1999)
Thompson, C. & Duncan, R. C. The soft gamma repeaters as very strongly magnetized neutron stars—I. Radiative mechanism for outbursts. Mon. Not. R. Astron. Soc. 275, 255–300 (1995)
Hurley, K. et al. An exceptionally bright flare from SGR 1806-20 and the origins of short-duration γ-ray bursts. Nature 434, 1098–1103 (2005)
Narayan, R., Paczynski, B. & Piran, T. Gamma-ray bursts as the death throes of massive binary stars. Astrophys. J. 395, L83–L86 (1992)
Mazzali, P. A. Applications of an improved Monte Carlo code to the synthesis of early-time supernova spectra. Astron. Astrophys. 363, 705–716 (2000)
Acknowledgements
We thank S. Kulkarni, C. Fryer, T. Janka, W. Hillebrandt and C. Kouveliotou for many discussions. This work was supported in part by the European Union, by the JSPS and MEXT in Japan, and by the USA NSF.
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Supplementary Figure 1
The spectra of 3 broad-lined SNe Ic a few days before maximum brightness. This figure shows a comparison of the spectrum of SN2006aj and those of two other Type Ic supernovae: SN1998bw, which produced a GRB (980425) and SN2002ap, which was not accompanied by a GRB. (PDF 38 kb)
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This file contains text to accompany the above Supplementary Figures. (PDF 40 kb)
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Mazzali, P., Deng, J., Nomoto, K. et al. A neutron-star-driven X-ray flash associated with supernova SN 2006aj. Nature 442, 1018–1020 (2006). https://doi.org/10.1038/nature05081
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DOI: https://doi.org/10.1038/nature05081
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