JWST Observations of Starbursts: Polycyclic Aromatic Hydrocarbon Emission at the Base of the M 82 Galactic Wind

Alberto D. Bolatto; Rebecca C. Levy; Elizabeth Tarantino; Martha L. Boyer; Deanne B. Fisher; Adam K. Leroy; Serena A. Cronin; Ralf S. Klessen; J. D. Smith; Dannielle A. Berg; Torsten Boeker; Leindert A. Boogaard; Eve C. Ostriker; Todd A. Thompson; Juergen Ott; Laura Lenkic; Laura A. Lopez; Daniel A. Dale; Sylvain Veilleux; Paul P. van der Werf; Simon C. O. Glover; Karin M. Sandstrom; Evan D. Skillman; John Chisholm; Vicente Villanueva; Thomas S. -Y. Lai; Sebastian Lopez; Elisabeth A. C. Mills; Kimberly L. Emig; Lee Armus; Divakara Maya; David S. Meier; Ilse De Looze; Rodrigo Herrera-Camus; Fabian Walter; Monica Relano; Hannah B. Koziol; Joshua Marvil; Maria J. Jimenez-Donaire; Paul Martini

arXiv · 2401.16648

JWST Observations of Starbursts: Polycyclic Aromatic Hydrocarbon Emission at the Base of the M 82 Galactic Wind

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Abstract

We present new observations of the central 1 kpc of the M 82 starburst obtained with the James Webb Space Telescope (JWST) near-infrared camera (NIRCam) instrument at a resolution ~0.05"-0.1" (~1-2 pc). The data comprises images in three mostly continuum filters (F140M, F250M, and F360M), and filters that contain [FeII] (F164N), H2 v=1-0 (F212N), and the 3.3 um PAH feature (F335M). We find prominent plumes of PAH emission extending outward from the central starburst region, together with a network of complex filamentary substructure and edge-brightened bubble-like features. The structure of the PAH emission closely resembles that of the ionized gas, as revealed in Paschen alpha and free-free radio emission. We discuss the origin of the structure, and suggest the PAHs are embedded in a combination of neutral, molecular, and photoionized gas.

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Alberto D. Bolatto, Rebecca C. Levy, Elizabeth Tarantino, Martha L. Boyer, Deanne B. Fisher, Adam K. Leroy, Serena A. Cronin, Ralf S. Klessen, J. D. Smith, Dannielle A. Berg, Torsten Boeker, Leindert A. Boogaard, Eve C. Ostriker, Todd A. Thompson, Juergen Ott, Laura Lenkic, Laura A. Lopez, Daniel A. Dale, Sylvain Veilleux, Paul P. van der Werf, Simon C. O. Glover, Karin M. Sandstrom, Evan D. Skillman, John Chisholm, Vicente Villanueva, Thomas S. -Y. Lai, Sebastian Lopez, Elisabeth A. C. Mills, Kimberly L. Emig, Lee Armus, Divakara Maya, David S. Meier, Ilse De Looze, Rodrigo Herrera-Camus, Fabian Walter, Monica Relano, Hannah B. Koziol, Joshua Marvil, Maria J. Jimenez-Donaire, Paul Martini. 2024-01-30. JWST Observations of Starbursts: Polycyclic Aromatic Hydrocarbon Emission at the Base of the M 82 Galactic Wind. https://arxiv.org/abs/2401.16648

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