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This content will become publicly available on April 8, 2026

Title: A Spectroscopically Calibrated Prescription for Extracting Polycyclic Aromatic Hydrocarbon Flux from JWST MIRI Imaging
Abstract We introduce a prescription for estimating the flux of the 7.7μm and 11.3μm polycyclic aromatic hydrocarbon (PAH) features from broadband JWST/MIRI images. Probing PAH flux with MIRI imaging data has advantages in field of view, spatial resolution, and sensitivity compared with MIRI spectral maps, but comparisons with spectra are needed to calibrate these flux estimations over a wide variety of environments. For 267 MIRI/MRS spectra from independent regions in the four luminous infrared galaxies (LIRGs) in the Great Observatories All-sky LIRG Survey Early Release Science program, we derive synthetic filter photometry and directly compare estimated PAH fluxes to those measured from detailed spectral fits. We find that for probing PAH 7.7μm, the best combination of filters is F560W, F770W, and either F1500W or F2100W, and the best for PAH 11.3μm is F560W, F1000W, F1130W, and F1500W. The prescription with these combinations yields predicted flux densities that typically agree with values from spectral decomposition within ∼7% and ∼5% for PAH 7.7 and 11.3μm, respectively.  more » « less
Award ID(s):
2239807
PAR ID:
10612030
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; « less
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
983
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
79
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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