A Framework for Analysing Nebular-Phase JWST Supernova Spectra with Application to Type Ic SN 2024aecx

Clicks: 7
ID: 333397
2026
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #1,304 of 1,339 articles by views in monthly notices of the royal astronomical society

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 1,339 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Abstract We analyse what physical quantities of SN ejecta can be obtained from a single epoch of nebular JWST spectroscopy. We provide an analytical framework, which together with a grid of helium star SUMO spectral synthesis models allows the determination of these quantities for any stripped-envelope SN. Using the framework, we derive critical electron densities for major emission lines, finding values in the range 105 − 106 cm−3. This means formation under close to LTE conditions for 200 – 300 days. We obtain ionisation fractions of Ni and Co, as well as the temperature and filling factor of the Fe/He zone, the 56Ni and stable nickel masses, the Ni/Fe ratio, and the optical depths $\tau _{[Ni\, {\small II}]\, 6.636}$ and $\tau _{[Co\, {\small II}]\, 10.52}$. Besides these constraints from iron group elements, one can also obtain the filling factor of the carbon burning (O/Ne/Mg) zone from [Ne ii] 12.81 μm, and the masses of Ar II and Cl I. We apply our methodology to a publicly available JWST spectrum of Type Ic SN 2024aecx. We find that this SN produced a chlorine mass of $M_{\mathrm{Cl\, I}} \simeq M_{\mathrm{Cl}} = 5.1^{+2.0}_{-1.6}\times 10^{-4}$ M⊙, a factor a few larger than expected from stellar evolution modeling. Furthermore, we find that the SN experienced an unexpectedly small ’Ni-bubble’ effect, with $\rho _{\mathrm{FeHe}} = 2.5^{+0.7}_{-0.4} \times 10^{-15}$ g cm−3 (or an expansion factor of 1 – 3 for the Ni-bubble, depending on the adopted model) at 167d for the silicon burning material. We also determine $M_{\mathrm{Ar\, II}} = 4.9^{+2.2}_{-1.5} \times 10^{-4}$ M⊙, which from ionisation fractions in our NLTE models yields a best estimate of MAr = 1.1 ± 0.4 × 10−3 M⊙.
Reference Key
openalex_W7223125545 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Stan Barmentloo, Anders Jerkstrand
Are you one of these authors? Claim your profile
Journal monthly notices of the royal astronomical society
Year 2026
DOI
10.1093/mnras/stag1990
URL
https://doi.org/10.1093/mnras/stag1990
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.