New HST Observations of High Velocity Lyman Alpha and Balmer Alpha in SNR 1987A

Abstract

We describe and model high velocity (~15,000 km/s) Lyman alpha and Balmer alpha emission from supernova remnant 1987A seen in September and October 1997 with the Space Telescope Imaging Spectrograph. Part of this emission comes from a reverse shock located at ~75% of the radius of the inner boundary of the inner circumstellar ring and confined within 30 degrees of the equatorial plane. Departure from axisymmetry in the Lyman alpha and Balmer alpha emission correlates with that seen in nonthermal radio emission and reveals an asymmetry in the circumstellar gas distribution. We also see diffuse high velocity Lyman alpha emission from supernova debris inside the reverse shock that may be due to excitation by nonthermal particles accelerated by the shock.

10 pages, 3 postscript figures. Submitted to ApJL on Sept 8, 1998; accepted Oct. 20, 1998. Text adjusted to referee's comments

References in corpus (2)

• Spatially Resolved STIS Spectroscopy of SN 1987A: Evidence for Shock Interaction with Circumstellar Gas
• The asymmetric radio remnant of SN 1987A

Cited by in corpus (19)

• The X-ray Remnant of SN1987A
• Effects of Jet-like Explosion in SN 1987A
• Balmer-Dominated Shocks Revisited
• Monitoring the Evolution of the X-ray Remnant of SN 1987A
• Modelling the Hubble Space Telescope Ultraviolet and Optical Spectrum of Spot 1 on the Circumstellar Ring of SN 1987A
• The X-ray Spectrum of Supernova Remnant 1987A
• On the Emergence and Discovery of Hot Spots in Supernova Remnant 1987A
• Evolution and Geometry of Hot Spots in Supernova Remnant 1987A
• Late Spectral Evolution of the Ejecta and Reverse Shock in SN1987A
• Fourier Modeling of the Radio Torus Surrounding Supernova 1987A
• The Ring Nebula Around the Blue Supergiant SBW1: Pre-Explosion Snapshot of a SN 1987A Twin
• The matter beyond the ring: the recent evolution of SN 1987A observed by the Hubble Space Telescope
• HST Spectroscopy of Spot 1 on the Circumstellar Ring of SN 1987A
• A Second Bright Source Detected Near SN1987A
• Thermal Emission and Radioactive Lines, but No Pulsar, in the Broadband X-Ray Spectrum of Supernova 1987A
• Evolution of the Reverse Shock Emission from SNR 1987A
• Coronal emission from the shocked circumstellar ring of SN 1987A
• Infrared emission towards 11 years after outburst: Properties of the circumstellar dust
• Spectral Evolution of the X-Ray Remnant of SN 1987A: A High-Resolution $Chandra$ HETG Study