학술논문
PHANGS–JWST First Results: Tracing the Diffuse Interstellar Medium with JWST Imaging of Polycyclic Aromatic Hydrocarbon Emission in Nearby Galaxies
Document Type
article
Author
Karin M. Sandstrom; Eric W. Koch; Adam K. Leroy; Erik Rosolowsky; Eric Emsellem; Rowan J. Smith; Oleg V. Egorov; Thomas G. Williams; Kirsten L. Larson; Janice C. Lee; Eva Schinnerer; David A. Thilker; Ashley T. Barnes; Francesco Belfiore; F. Bigiel; Guillermo A. Blanc; Alberto D. Bolatto; Médéric Boquien; Yixian Cao; Jérémy Chastenet; Mélanie Chevance; I-Da Chiang; Daniel A. Dale; Christopher M. Faesi; Simon C. O. Glover; Kathryn Grasha; Brent Groves; Hamid Hassani; Jonathan D. Henshaw; Annie Hughes; Jaeyeon Kim; Ralf S. Klessen; Kathryn Kreckel; J. M. Diederik Kruijssen; Laura A. Lopez; Daizhong Liu; Sharon E. Meidt; Eric J. Murphy; Hsi-An Pan; Miguel Querejeta; Toshiki Saito; Amy Sardone; Mattia C. Sormani; Jessica Sutter; Antonio Usero; Elizabeth J. Watkins
Source
The Astrophysical Journal Letters, Vol 944, Iss 2, p L8 (2023)
Subject
Language
English
ISSN
2041-8213
2041-8205
2041-8205
Abstract
JWST observations of polycyclic aromatic hydrocarbon (PAH) emission provide some of the deepest and highest resolution views of the cold interstellar medium (ISM) in nearby galaxies. If PAHs are well mixed with the atomic and molecular gas and illuminated by the average diffuse interstellar radiation field, PAH emission may provide an approximately linear, high-resolution, high-sensitivity tracer of diffuse gas surface density. We present a pilot study that explores using PAH emission in this way based on Mid-Infrared Instrument observations of IC 5332, NGC 628, NGC 1365, and NGC 7496 from the Physics at High Angular resolution in Nearby GalaxieS-JWST Treasury. Using scaling relationships calibrated in Leroy et al., scaled F1130W provides 10–40 pc resolution and 3 σ sensitivity of Σ _gas ∼ 2 M _⊙ pc ^−2 . We characterize the surface densities of structures seen at