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Type IIn supernovae at redshift z approximately 2 from archival data
Jeff Cooke1, Mark Sullivan, Elizabeth J Barton
1Center for Cosmology, Department of Physics and Astronomy, University of California, Irvine, California 92697-4574, USA. cooke@uci.edu
Nature
|July 10, 2009
Summary
Three type IIn supernovae were discovered at high redshifts using a novel method. This finding supports models of massive star formation and challenges theories of evolving stellar initial mass functions.
Area of Science:
- Astronomy
- Cosmology
- Astrophysics
Background:
- Type Ia supernovae are observed up to redshift z ≈ 1.7, and Type II supernovae up to z ≈ 0.7.
- Type IIn supernovae, luminous core-collapse explosions of massive stars, are bright in ultraviolet and exhibit strong emission lines, enabling detection at high redshifts (z ≈ 2).
Purpose of the Study:
- To report the discovery of three spectroscopically confirmed type IIn supernovae at high redshifts.
- To utilize a method exploiting the unique properties of type IIn supernovae for high-redshift detection.
- To probe massive star formation at high redshift.
Main Methods:
- Archival data analysis using a specialized detection method.
- Spectroscopic confirmation of supernova types and redshifts.
- Exploitation of ultraviolet brightness and emission line characteristics of type IIn supernovae.
Main Results:
- Discovery of three type IIn supernovae at redshifts z = 0.808, 2.013, and 2.357.
- The observed number of type IIn supernovae is consistent with a local stellar initial mass function.
- The findings challenge models of an evolving initial mass function.
Conclusions:
- Type IIn supernovae are valuable probes of massive star formation in the early universe.
- Current observations align with standard stellar initial mass function models.
- Further research is needed to reconcile observations with evolving initial mass function theories.
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