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A low-energy core-collapse supernova without a hydrogen envelope
S Valenti1, A Pastorello, E Cappellaro
1Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, UK. s.valenti@qub.ac.uk
Nature
|June 5, 2009
Summary
Astronomers discovered SN 2008ha, a faint, hydrogen-poor supernova. This finding may link faint supernovae to long-duration gamma-ray bursts, previously unassociated with visible supernovae.
Area of Science:
- * Astrophysics
- * Stellar Evolution
- * Supernova Physics
Background:
- * Massive stars (>25-30 solar masses) may become hydrogen-deficient Wolf-Rayet stars due to strong stellar winds.
- * Core collapse in massive stars can produce low-energy supernovae with faint luminosity and low kinetic energy ejecta.
- * An alternative origin for low-energy supernovae is the collapse of oxygen-neon cores in stars of 7-9 solar masses.
- * Previously, no faint, hydrogen-deficient, core-collapse supernovae had been observed.
Purpose of the Study:
- * To report the discovery and characteristics of SN 2008ha, a faint hydrogen-poor supernova.
- * To investigate the potential misclassification of similar faint supernovae as peculiar thermonuclear events (SN 2002cx-like).
- * To explore the connection between faint, hydrogen-stripped core-collapse supernovae and long-duration gamma-ray bursts.
Main Methods:
- * Observational astronomy: Detection and analysis of SN 2008ha.
- * Spectroscopic analysis to determine supernova properties (e.g., hydrogen deficiency, luminosity).
- * Theoretical modeling to link observed supernova characteristics to stellar evolution pathways.
Main Results:
- * SN 2008ha identified as a faint, hydrogen-poor supernova.
- * Proposal that similar events may have been misclassified as SN 2002cx-like supernovae.
- * Potential association established between faint, hydrogen-stripped supernovae and long-duration gamma-ray bursts.
Conclusions:
- * SN 2008ha represents a new class of observed faint supernovae.
- * The misclassification of similar events could explain the previous lack of observation.
- * This discovery provides a potential observational link to long-duration gamma-ray bursts.
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