Abstract
Gamma-ray bursts (GRBs) are known to come in two duration classes1, separated at ∼2 s. Long-duration bursts originate from star-forming regions in galaxies2, have accompanying supernovae when these are near enough to observe and are probably caused by massive-star collapsars3. Recent observations4,5,6,7,8,9,10 show that short-duration bursts originate in regions within their host galaxies that have lower star-formation rates, consistent with binary neutron star or neutron star–black hole mergers11,12. Moreover, although their hosts are predominantly nearby galaxies, no supernovae have been so far associated with short-duration GRBs. Here we report that the bright, nearby GRB 060614 does not fit into either class. Its ∼102-s duration groups it with long-duration GRBs, while its temporal lag and peak luminosity fall entirely within the short-duration GRB subclass. Moreover, very deep optical observations exclude an accompanying supernova13,14,15, similar to short-duration GRBs. This combination of a long-duration event without an accompanying supernova poses a challenge to both the collapsar and the merging-neutron-star interpretations and opens the door to a new GRB classification scheme that straddles both long- and short-duration bursts.
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References
Kouveliotou, C. et al. Identification of two classes of gamma-ray bursts. Astrophys. J. 413, L101–L104 (1993)
Fruchter, A. et al. Long γ-ray bursts and core-collapse supernovae have different environments. Nature 441, 463–468 (2006)
Woosley, S. E. Gamma-ray bursts from stellar mass accretion disks around black holes. Astrophys. J. 405, 273–277 (1993)
Gehrels, N. et al. A short gamma-ray burst apparently associated with an elliptical galaxy at z = 0.225. Nature 437, 851–854 (2005)
Fox, D. B. et al. The afterglow of GRB 050709 and the nature of the short-hard gamma-ray bursts. Nature 437, 845–851 (2005)
Villasenor, J. S. et al. Discovery of the short gamma-ray burst GRB 050709. Nature 437, 855–878 (2005)
Hjorth, J. et al. The optical afterglow of the short gamma-ray burst GRB 050709. Nature 437, 859–861 (2005)
Barthelmy, S. D. et al. An origin for short gamma-ray bursts unassociated with current star formation. Nature 438, 994–996 (2005)
Berger, E. et al. The afterglow and elliptical host galaxy of the short gamma-ray burst GRB 050724. Nature 438, 988–990 (2005)
Bloom, J. S. et al. Closing in on a short-hard burst progenitor: constraints from early-time optical imaging and spectroscopy of a possible host galaxy of GRB 050509b. Astrophys. J. 638, 354–368 (2006)
Paczynski, B. Gamma-ray bursters at cosmological distances. Astrophys. J. 308, L43–L46 (1986)
Eichler, D., Livio, M., Piran, T. & Schramm, D. N. Nucleosynthesis, neutrino bursts and gamma-rays from coalescing neutron stars. Nature 340, 126–127 (1989)
Fynbo, J. P. U. et al. No supernovae associated with two long-duration γ-ray bursts. Nature doi: 10.1038/nature05375 (this issue); preprint at (astro-ph 0608313) (2006)
Gal-Yam, A. et al. A novel explosive process is required for the γ-ray burst GRB 060614. Nature doi: 10.1038/nature05373 (this issue); preprint at 〈http://arxiv.org/astro-ph/0608257〉 (2006)
Della Valle, M. et al. An enigmatic long-lasting γ-ray burst not accompanied by a bright supernova. Nature doi: 10.1038/nature05374 (this issue); preprint at 〈http://arxiv.org/astro-ph/0608322〉 (2006)
Gehrels, N. et al. The Swift gamma ray burst mission. Astrophys. J. 611, 1005–1020 (2004)
Price, P. A., Berger, E. & Fox, D. B. GRB 060614: redshift. GCN Circ. 5275, (2006)
Schaefer, B. E. & Xiao, L. GRB060614 is at high redshift, so no new class of gamma-ray bursts is required. Preprint at 〈http://arxiv.org/astro-ph/0608441〉 (2006)
Cobb, B. E. et al. Could GRB 060614 and its presumed host galaxy be a chance superposition?. Astrophys. J. 651, L85–L88 (2006)
Kaneko, Y. et al. Prompt and afterglow emission properties of gamma-ray bursts with spectroscopically identified supernovae. Astrophys. J. (in the press); preprint at 〈http://arxiv.org/astro-ph/0607110〉 (2006)
Norris, J. P. & Bonnell, J. T. Short gamma-ray bursts with extended emission. Astrophys. J. 643, 266–275 (2006)
Mazets, E. P. et al. Konus Catalog of Short GRBs 〈http://www.ioffe.ru/LEA/shortGRBs/Catalog/〉. Preprint at 〈http://arxiv.org/astro-ph/astro-ph0209219 〉 (Ioffe Physico-Technical Institute, Laboratory for Experimental Astrophysics, 2002)
Norris, J. P. Implications of the lag-luminosity relationship for unified gamma-ray burst paradigms. Astrophys. J. 579, 386–403 (2002)
Donaghy, T. Q. et al. HETE-2 localizations and observations of four short gamma-ray bursts: GRBs 010326B, 040802, 051211 and 060121. Preprint at 〈http://arxiv.org/astro-ph/0605570〉 (2006)
Zhang, W., Woosley, S. E. & MacFadyen, A. I. Numerical simulations of relativistic jets in collapsars. Astrophys. J. 586, 356–371 (2003)
Woosley, S. E. & Bloom, J. S. The supernova–gamma-ray burst connection. Annu. Rev. Astron. Astrophys. 44, 507–561 (2006)
Narayan, R., Piran, T. & Kumar, P. Accretion models of gamma-ray bursts. Astrophys. J. 557, 949–957 (2001)
Faber, J. A. et al. Relativistic binary merger simulations and short gamma-ray bursts. Astrophys. J. 641, L93–L96 (2006)
Golenetskii, S. et al. Konus-Wind observation of GRB 060614. GCN Circ. 5264, (2006)
Vanderspek, R. et al. Observations of the gamma ray burst GRB 030329: Evidence for a soft underlying component. Astrophys. J. 617, 1251–1257 (2004)
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Gehrels, N., Norris, J., Barthelmy, S. et al. A new γ-ray burst classification scheme from GRB 060614. Nature 444, 1044–1046 (2006). https://doi.org/10.1038/nature05376
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DOI: https://doi.org/10.1038/nature05376
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