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Updated: May 2, 2026
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
16.9K
No supernovae associated with two long-duration gamma-ray bursts.
Johan P U Fynbo1, Darach Watson, Christina C Thöne
1Dark Cosmology Centre, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark. jfynbo@dark-cosmology.dk
Nature
|December 22, 2006
Summary
Two long-duration gamma-ray bursts (GRBs) lacked supernova emissions, challenging the standard collapsar model. This suggests a new type of massive star death, distinct from previously observed GRB-associated supernovae.
Area of Science:
- Astrophysics
- Cosmic explosions
- Gamma-ray astronomy
Background:
- Long-duration gamma-ray bursts (GRBs) are linked to the collapse of massive stars.
- The collapsar model predicts a supernova for every long-duration GRB.
- Previous observations confirmed this association with nearby GRBs.
Purpose of the Study:
- Investigate the association between GRBs and supernovae.
- Determine if GRB 060505 and GRB 060614 were accompanied by supernovae.
- Explore implications for models of massive stellar death.
Main Methods:
- Multi-band observations of early GRB afterglows.
- Spectroscopy of host galaxies.
- Deep supernova searches with limits hundreds of times fainter than typical.
Main Results:
- GRB 060505 and GRB 060614 showed no detectable supernova emission.
- Limits were significantly deeper than those for archetypal supernovae like SN 1998bw.
- Host galaxies were actively star-forming, ruling out significant dust obscuration.
Conclusions:
- The absence of supernovae challenges the standard collapsar model for these GRBs.
- Suggests a new phenomenological class of massive stellar death.
- Highlights diversity in the end-of-life pathways for massive stars.
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