Search

The ring collision in SN 1987 offers an opportunity to study the development of radiative shocks in real time. We here review the optical and near-IR observations of the collision and discuss them in relation to observations at other wavelengths. In particular, the shock diagnostics provided by the coronal lines, the line profiles and the fluxes are discussed. [ABSTRACT FROM AUTHOR]

A search for O VI 1032-38 Å emission from the circumstellar shock interaction zones of SN 1987A was made with the FUSE satellite. The shock interaction of supernova ejecta with the dense inner ring began in the mid-1990s. Broad (FWHM ∼300 km s-1) emission from optical coronal lines (e.g. [Fe X], [Fe XI], and [Fe XIV]) has emerged and increased exponentially in strength. O VI emission is expected to track the coronal lines and is expected to be the primary cooling transition for the million-degree shocked gas. In the most recent FUSE observation of SN 1987A, June 2004, a weak broad O VI feature may be present. An upper limit on the intrinsic O VI flux is ∼1×10-13 erg cm-2 s-1 (corrected for foreground Galactic and LMC extinction). A follow-up observation of planned for mid-2007. [ABSTRACT FROM AUTHOR]

The X-ray emission from the Type II supernovae SNe 1993J and 1998S is modelled using the numerical code described in Nymark et al. (2006), assuming that most of the observed X-ray emission comes from the reverse shock created by the interaction between the supernova ejecta and a dense circumstellar medium. We find that the spectra of both SNe are compatible with a CNO-enriched composition. For SN 1998S we find evidence for a component from both the reverse and forward shock, while the X-ray flux for SN 1993J is dominated by the reverse shock. [ABSTRACT FROM AUTHOR]

After nearly two decades at least five emission mechanisms can be found in SN 1987A. The ejecta continue to glow as a result of the radioactive decay of long-lived nuclei (mostly 44Ti), but is fading continuously because of the expansion and the reduced opacity. The nearly stationary rings around SN 1987A are still fluorescing from the recombination of matter originally excited by the soft X-ray emission from the shock breakout at explosion. The supernova shock reached the inner circumstellar ring about ten years ago and the forward shock is moving through the inner ring and leaves shocked material behind. This material is excited and accelerated. The reverse shock illuminates the fast-moving supernova ejecta as it catches up. And, finally light echoes in nearby interstellar matter can still be observed. We present here high resolution spectroscopy in the optical and integral-field spectroscopy in the near infrared of SN 1987A and its rings. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The Far Ultraviolet Spectroscopic Explorer (FUSE) was used to search for emission from the shock interaction of the ejecta of SN 1987A with its circumstellar material. FUSE observations of SN 1987A between 2000 and 2007 did not detect broad O VI emission. However, O VI emission was detected in 2000–2001 with a narrow line width (FWHM<35 km s-1) and a heliocentric radial velocity of +280 km s-1. This places the emitting gas at rest relative to the supernova and is interpreted as emission from unshocked circumstellar gas. This narrow emission had disappeared in 2007 (and possibly earlier) as a result of the advancing shock overtaking the H II region that was flash ionized by the supernova explosion in 1987. [ABSTRACT FROM AUTHOR]