The Origin of the Crab Nebula
Abstract
We propose NIRCam and MIRI imaging and MIRI MRS spectroscopy of the iconic Crab Nebula in order to test models of the progenitor and explosion mechanism by mapping the dust distribution, imaging the iron emission, measuring Ni/Fe ratios, and searching for dust compositional variations. The imaging requested will permit us to separate the bright line and synchrotron emission from dust emission and produce the first complete mapping of the dust distribution in the Crab Nebula. The [Fe II] emission will be used to study the spatial distribution of Fe in the remnant and derive its total mass. The MIRI MRS spectra will be used to measure the Ni/Fe ratios across the filaments and determine the dust composition at two positions that may have different ejecta and swept-up circumstellar contributions. These observational measurements can elucidate differences in predictions for the two competing explosion mechanisms for the Crab's progenitor (electron capture vs. Fe-core collapse) and determine whether a dense circumstellar medium, possibly distributed in a disk around the progenitor, has been important in shaping the Crab Nebula as it is observed today. The total requested time for the program is 22.57 hours.
- Publication:
-
JWST Proposal. Cycle 1
- Pub Date:
- March 2021
- Bibcode:
- 2021jwst.prop.1714T