Narrow ultraviolet emission lines from SN 1987A - evidence for CNO processing in the progenitor

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/167022· OSTI ID:6146751

Fransson, C; Cassatella, A; Gilmozzi, R; Kirshner, R P; Panagia, N; Sonneborn, G

Results from UV observations of SN 1987A with the IUE satellite are presented, showing that emission lines of He II, C III, N III, N IV, N V, and O III increase in strength with time after May 24, 1987. It is found that increased emission originated in a photoionized low-density circumstellar gas, lost by the progenitor in its red supergiant phase. A nebular analysis reveals a large nitrogen overabundance, indicating that the gas has undergone substantial CNO processing. This suggests that the progenitor of SN 1987A lost much of its hydrogen envelope before the explosion. The findings are consistent with models in which a red supergiant evolves to the blue supergiant stage before exploding. 65 references.

• Research Organization: Stockholms Observatorium, Saltsjobaden (Sweden); IUE Observatory, Madrid (Spain); Space Telescope Science Institute, Baltimore, MD (USA); Catania Universita (Italy); Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA)
• OSTI ID: 6146751
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 336; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
CNO CYCLE
COSMIC GASES
ELEMENTS
EMISSION SPECTRA
ERUPTIVE VARIABLE STARS
FLUIDS
GASES
GIANT STARS
IONIZATION
MASS TRANSFER
NITROGEN
NONMETALS
PHOTOIONIZATION
SPECTRA
STAR BURNING
STAR EVOLUTION
STARS
SUPERGIANT STARS
SUPERNOVAE
ULTRAVIOLET SPECTRA
VARIABLE STARS