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Literature
Date: 2/3/2025

Arxiv: A Spectroscopically Calibrated Prescription for Extracting PAH Flux from JWST MIRI Imaging Published: 1/31/2025 8:52:08 PM Updated: 1/31/2025 8:52:08 PM


Paper abstract: We introduce a prescription for estimating the flux of the 7.7 micron and11.3 micron\ polycyclic aromatic hydrocarbon (PAH) features from broadbandJWST/MIRI images. Probing PAH flux with MIRI imaging data has advantages infield of view, spatial resolution, and sensitivity compared with MIRI spectralmaps, but comparisons with spectra are needed to calibrate these fluxestimations over a wide variety of environments. For 267 MIRI/MRS spectra fromindependent regions in the four luminous infrared galaxies (LIRGs) in the GreatObservatories All-sky LIRG Survey (GOALS) early release science program, wederive synthetic filter photometry and directly compare estimated PAH fluxes tothose measured from detailed spectral fits. We find that for probing PAH 7.7micron, the best combination of filters is F560W, F770W, and either F1500W orF2100W, and the best for PAH 11.3 micron is F560W, F1000W, F1130W, and F1500W.The prescription with these combinations yields predicted flux densities thattypically agree with values from spectral decomposition within ~7% and ~5% forPAH 7.7 and 11.3 micron, respectively.