Mid-infrared imaging of Supernova 1987A
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Author/Creator ORCID
Date
2022-10-21
Type of Work
Department
Program
Citation of Original Publication
Mikako Matsuura, Roger Wesson, Richard G Arendt, Eli Dwek, James M De Buizer, John Danziger, Patrice Bouchet, M J Barlow, Phil Cigan, Haley L Gomez, Jeonghee Rho, Margaret Meixner, Mid-infrared imaging of Supernova 1987A, Monthly Notices of the Royal Astronomical Society, Volume 517, Issue 3, December 2022, Pages 4327–4336, https://doi.org/10.1093/mnras/stac3036
Rights
This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
Public Domain Mark 1.0
Public Domain Mark 1.0
Subjects
Abstract
At a distance of 50 kpc, Supernova 1987A is an ideal target to study how a young supernova (SN) evolves in time. Its equatorial
ring, filled with material expelled from the progenitor star about 20,000 years ago, has been engulfed with SN blast waves.
Shocks heat dust grains in the ring, emitting their energy at mid-infrared (IR) wavelengths We present ground-based 10–18 𝜇m
monitoring of the ring of SN 1987A from day 6067 to 12814 at a resolution of 0.5”, together with SOFIA photometry at
10–30 𝜇m. The IR images in the 2000’s (day 6067–7242) showed that the shocks first began brightening the east side of the ring.
Later, our mid-IR images from 2017 to 2022 (day 10952–12714) show that dust emission is now fading in the east, while it has
brightened on the west side of the ring. Because dust grains are heated in the shocked plasma, which can emit X-rays, the IR and
X-ray brightness ratio represent shock diagnostics. Until 2007 the IR to X-ray brightness ratio remained constant over time, and
during this time shocks seemed to be largely influencing the east side of the ring. However, since then, the IR to X-ray ratio has
been declining, due to increased X-ray brightness. Whether the declining IR brightness is because of dust grains being destroyed
or being cooled in the post-shock regions will require more detailed modelling.