A JWST Survey of the Supernova Remnant Cassiopeia A
Abstract
We present initial results from a JWST survey of the youngest Galactic core-collapse supernova remnant Cassiopeia A (Cas A), made up of NIRCam and MIRI imaging mosaics that map emission from the main shell, interior, and surrounding circumstellar/interstellar material (CSM/ISM). We also present four exploratory positions of MIRI/MRS IFU spectroscopy that sample ejecta, CSM, and associated dust from representative shocked and unshocked regions. Surprising discoveries include: 1) a web-like network of unshocked ejecta filaments resolved to 0.01 pc scales exhibiting an overall morphology consistent with turbulent mixing of cool, low-entropy matter from the progenitor's oxygen layer with hot, high-entropy matter heated by neutrino interactions and radioactivity, 2) a thick sheet of dust-dominated emission from shocked CSM seen in projection toward the remnant's interior pockmarked with small (approximately one arcsecond) round holes formed by knots of high-velocity ejecta that have pierced through the CSM and driven expanding tangential shocks, 3) dozens of light echoes with angular sizes between 0.1 arcsecond to 1 arcminute reflecting previously unseen fine-scale structure in the ISM. NIRCam observations place new upper limits on infrared emission from the neutron star in Cas A's center and tightly constrain scenarios involving a possible fallback disk. These JWST survey data and initial findings help address unresolved questions about massive star explosions that have broad implications for the formation and evolution of stellar populations, the metal and dust enrichment of galaxies, and the origin of compact remnant objects.
Keywords
Cite
@article{arxiv.2401.02477,
title = {A JWST Survey of the Supernova Remnant Cassiopeia A},
author = {Dan Milisavljevic and Tea Temim and Ilse De Looze and Danielle Dickinson and J. Martin Laming and Robert Fesen and John C. Raymond and Richard G. Arendt and Jacco Vink and Bettina Posselt and George G. Pavlov and Ori D. Fox and Ethan Pinarski and Bhagya Subrayan and Judy Schmidt and William P. Blair and Armin Rest and Daniel Patnaude and Bon-Chul Koo and Jeonghee Rho and Salvatore Orlando and Hans-Thomas Janka and Moira Andrews and Michael J. Barlow and Adam Burrows and Roger Chevalier and Geoffrey Clayton and Claes Fransson and Christopher Fryer and Haley L. Gomez and Florian Kirchschlager and Jae-Joon Lee and Mikako Matsuura and Maria Niculescu-Duvaz and Justin D. R. Pierel and Paul P. Plucinsky and Felix D. Priestley and Aravind P. Ravi and Nina S. Sartorio and Franziska Schmidt and Melissa Shahbandeh and Patrick Slane and Nathan Smith and Kathryn Weil and Roger Wesson and J. Craig Wheeler},
journal= {arXiv preprint arXiv:2401.02477},
year = {2024}
}
Comments
27 pages, 10 figures, now published in ApJL