Type IIn supernovae at redshift z approximate to 2 from archival data

Article

关键词: GALAXIES;    Z-SIMILAR-TO-3;    TELESCOPE;    EPOCH;   

DOI  :  10.1038/nature08082

来源: SCIE

【 摘 要 】

Supernovae have been confirmed to redshift z approximate to 1.7 (refs 1, 2) for type Ia (thermonuclear detonation of a white dwarf) and to z approximate to 0.7 (refs 1, 3-5) for type II (collapse of the core of the star). The subclass type IIn (ref. 6) supernovae are luminous(7-9) core-collapse explosions of massive stars(8-11) and, unlike other types, are very bright in the ultraviolet(12-15), which should enable them to be found optically at redshifts z approximate to 2 and higher(14,16). In addition, the interaction of the ejecta with circumstellar material creates strong, long-lived emission lines that allow spectroscopic confirmation of many events of this type at z approximate to 2 for 3-5 years after explosion (ref. 14). Here we report three spectroscopically confirmed type IIn supernovae, at redshifts z = 0.808, 2.013 and 2.357, detected in archival data using a method(14) designed to exploit these properties at z approximate to 2. Type IIn supernovae directly probe the formation of massive stars at high redshift. The number found to date is consistent with the expectations of a locally measured(17) stellar initial mass function, but not with an evolving initial mass function proposed(18-20) to explain independent observations at low and high redshift.

【 授权许可】

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