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arXiv · 2212.00130

PHANGS-JWST First Results: The Influence of Stellar Clusters on PAHs in Nearby Galaxies

Daniel A. Dale·Médéric Boquien·Ashley T. Barnes·Francesco Belfiore·F. Bigiel·Yixian Cao·Rupali Chandar·Jérémy Chastenet·Mélanie Chevance·Sinan Deger·Oleg V. Egorov·Kathryn Grasha·Brent Groves·Hamid Hassani·Kiana F. Henny·Ralf S. Klessen·Kathryn Kreckel·J. M. Diederik Kruijssen·Kirsten L. Larson·Janice C. Lee·Adam K. Leroy·Daizhong Liu·Eric J. Murphy·Erik Rosolowsky·Karin Sandstrom·Eva Schinnerer·Jessica Sutter·David A. Thilker·Elizabeth J. Watkins·Bradley C. Whitmore·Thomas G. Williams
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Abstract

We present a comparison of theoretical predictions of dust continuum and polycyclic aromatic hydrocarbon (PAH) emission with new JWST observations in three nearby galaxies: NGC 628, NGC 1365, and NGC 7496. Our analysis focuses on a total of 1063 compact stellar clusters and 2654 stellar associations previously characterized by HST in the three galaxies. We find that the distributions and trends in the observed PAH-focused infrared colors generally agree with theoretical expectations, and that the bulk of the observations is more aligned with models of larger, ionized PAHs. These JWST data usher in a new era of probing interstellar dust and studying how the intense radiation fields near stellar clusters and associations play a role in shaping the physical properties of PAHs.

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Daniel A. Dale, Médéric Boquien, Ashley T. Barnes, Francesco Belfiore, F. Bigiel, Yixian Cao, Rupali Chandar, Jérémy Chastenet, Mélanie Chevance, Sinan Deger, Oleg V. Egorov, Kathryn Grasha, Brent Groves, Hamid Hassani, Kiana F. Henny, Ralf S. Klessen, Kathryn Kreckel, J. M. Diederik Kruijssen, Kirsten L. Larson, Janice C. Lee, Adam K. Leroy, Daizhong Liu, Eric J. Murphy, Erik Rosolowsky, Karin Sandstrom, Eva Schinnerer, Jessica Sutter, David A. Thilker, Elizabeth J. Watkins, Bradley C. Whitmore, Thomas G. Williams. 2022-11-30. PHANGS-JWST First Results: The Influence of Stellar Clusters on PAHs in Nearby Galaxies. https://doi.org/10.3847/2041-8213%2Faca769

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