학술논문
Ejecta, Rings, and Dust in SN 1987A with JWST MIRI/MRS
Document Type
Working Paper
Author
Jones, O. C.; Kavanagh, P. J.; Barlow, M. J.; Temim, T.; Fransson, C.; Larsson, J.; Blommaert, J. A. D. L.; Meixner, M.; Lau, R. M.; Sargent, B.; Bouchet, P.; Hjorth, J.; Wright, G. S.; Coulais, A.; Fox, O. D.; Gastaud, R.; Glasse, A.; Habel, N.; Hirschauer, A. S.; Jaspers, J.; Krause, O.; Lenkić; Nayak, O.; Rest, A.; Tikkanen, T.; Wesson, R.; Colina, L.; van Dishoeck, E. F.; Güdel, M.; Henning, Th.; Lagage, P. -O.; Östlin; Ray, T. P.; Vandenbussche, B.
Source
Subject
Language
Abstract
Supernova (SN) 1987A is the nearest supernova in $\sim$400 years. Using the {\em JWST} MIRI Medium Resolution Spectrograph, we spatially resolved the ejecta, equatorial ring (ER) and outer rings in the mid-infrared 12,927 days after the explosion. The spectra are rich in line and dust continuum emission, both in the ejecta and the ring. Broad emission lines (280-380~km~s$^{-1}$ FWHM) seen from all singly-ionized species originate from the expanding ER, with properties consistent with dense post-shock cooling gas. Narrower emission lines (100-170~km~s$^{-1}$ FWHM) are seen from species originating from a more extended lower-density component whose high ionization may have been produced by shocks progressing through the ER, or by the UV radiation pulse associated with the original supernova event. The asymmetric east-west dust emission in the ER has continued to fade, with constant temperature, signifying a reduction in dust mass. Small grains in the ER are preferentially destroyed, with larger grains from the progenitor surviving the transition from SN into SNR. The ER is fit with a single set of optical constants, eliminating the need for a secondary featureless hot dust component. We find several broad ejecta emission lines from [Ne~{\sc ii}], [Ar~{\sc ii}], [Fe~{\sc ii}], and [Ni~{\sc ii}]. With the exception of [Fe~{\sc ii}]~25.99$\mu$m, these all originate from the ejecta close to the ring and are likely being excited by X-rays from the interaction. The [Fe~{\sc ii}]~5.34$\mu$m to 25.99$\mu$m line ratio indicates a temperature of only a few hundred K in the inner core, consistent with being powered by ${}^{44}$Ti decay.
Comment: 27 pages, 16 figures, 4 tables. Accepted ApJ
Comment: 27 pages, 16 figures, 4 tables. Accepted ApJ