Final Spitzer IRAC Observations of the Rise and Fall of SN 1987A

Abstract

Spitzer's final Infrared Array Camera (IRAC) observations of SN 1987A show the 3.6 and 4.5 $\mu$m emission from the equatorial ring (ER) continues a period of steady decline. Deconvolution of the images reveals that the emission is dominated by the ring, not the ejecta, and is brightest on the west side. Decomposition of the marginally resolved emission also confirms this, and shows that the west side of the ER has been brightening relative to the other portions of the ER. The infrared (IR) morphological changes resemble those seen in both the soft X-ray emission and the optical emission. The integrated ER light curves at 3.6 and 4.5 $\mu$m are more similar to the optical light curves than the soft X-ray light curve, though differences would be expected if dust is responsible for this emission and its destruction is rapid. Future observations with the James Webb Space Telescope will continue to monitor the ER evolution, and will reveal the true spectrum and nature of the material responsible for the broadband emission at 3.6 and 4.5 $\mu$m. The present observations also serendipitously reveal a nearby variable source, subsequently identified as a Be star, that has gone through a multi-year outburst during the course of these observations.

12 pages, 9 figures. Accepted for publication in the ApJ

References in corpus (9)

• The James Webb Space Telescope
• Early Science with SOFIA, the Stratospheric Observatory for Infrared Astronomy
• Spitzer SAGE Infrared Photometry of Massive Stars in the Large Magellanic Cloud
• High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta
• Chandra Observes the End of an Era SN 1987A
• The Destruction of the Circumstellar Ring of SN 1987A
• Infrared and X-Ray Evidence for Circumstellar Grain Destruction by the Blast Wave of Supernova 1987A
• The matter beyond the ring: the recent evolution of SN 1987A observed by the Hubble Space Telescope
• The Hubble Catalog of Variables (HCV)

Cited by in corpus (11)

• JWST NIRSpec observations of Supernova 1987A -- from the inner ejecta to the reverse shock
• Thermal Emission and Radioactive Lines, but No Pulsar, in the Broadband X-Ray Spectrum of Supernova 1987A
• Spectral Evolution of the X-Ray Remnant of SN 1987A: A High-Resolution $Chandra$ HETG Study
• Latest Evolution of the X-Ray Remnant of SN 1987A: Beyond the Inner Ring
• Rescued from oblivion: detailed analysis of archival {\it Spitzer} data of SN~1993J
• Mid-infrared imaging of Supernova 1987A
• Polarized radio emission unveils the structure of the pre-supernova circumstellar magnetic field and the radio emission in SN1987A
• The distribution of radio quiet active galactic nuclei in the star formation-stellar mass plane
• Near-infrared evolution of the equatorial ring of SN 1987A
• JWST/MIRI detects the dusty SN1993J about 30 years after explosion
• Spitzer's Last Look at Extragalactic Explosions: Long-Term Evolution of Interacting Supernovae