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arXiv · 2310.08720

PDRs4All III: JWST's NIR spectroscopic view of the Orion Bar

Els Peeters·Emilie Habart·Olivier Berne·Ameek Sidhu·Ryan Chown·Dries Van De Putte·Boris Trahin·Ilane Schroetter·Amelie Canin·Felipe Alarcon·Bethany Schefter·Baria Khan·Sofia Pasquini·Alexander G. G. M. Tielens·Mark G. Wolfire·Emmanuel Dartois·Javier R. Goicoechea·Alexandros Maragkoudakis·Takashi Onaka·Marc W. Pound·Silvia Vicente·Alain Abergel·Edwin A. Bergin·Jeronimo Bernard-Salas·Christiaan Boersma·Emeric Bron·Jan Cami·Sara Cuadrado·Daniel Dicken·Meriem Elyajour·Asuncion Fuente·Karl D. Gordon·Lina Issa·Christine Joblin·Olga Kannavou·Ozan Lacinbala·David Languignon·Romane Le Gal·Raphael Meshaka·Yoko Okada·Massimo Robberto·Markus Roellig·Thiebaut Schirmer·Benoit Tabone·Marion Zannese·Isabel Aleman·Louis Allamandola·Rebecca Auchettl·Giuseppe Antonio Baratta·Salma Bejaoui·Partha P. Bera·John H. Black·Francois Boulanger·Jordy Bouwman·Bernhard Brandl·Philippe Brechignac·Sandra Brunken·Mridusmita Buragohain·Andrew Burkhardt·Alessandra Candian·Stephanie Cazaux·Jose Cernicharo·Marin Chabot·Shubhadip Chakraborty·Jason Champion·Sean W. J. Colgan·Ilsa R. Cooke·Audrey Coutens·Nick L. J. Cox·Karine Demyk·Jennifer Donovan Meyer·Sacha Foschino·Pedro Garcia-Lario·Maryvonne Gerin·Carl A. Gottlieb·Pierre Guillard·Antoine Gusdorf·Patrick Hartigan·Jinhua He·Eric Herbst·Liv Hornekaer·Cornelia Jager·Eduardo Janot-Pacheco·Michael Kaufman·Sarah Kendrew·Maria S. Kirsanova·Pamela Klaassen·Sun Kwok·Alvaro Labiano·Thomas S. -Y. Lai·Timothy J. Lee·Bertrand Lefloch·Franck Le Petit·Aigen Li·Hendrik Linz·Cameron J. Mackie·Suzanne C. Madden·Joelle Mascetti·Brett A. McGuire·Pablo Merino

Abstract

(Abridged) We investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the HII region to the atomic PDR (crossing the ionisation front (IF)), and the subsequent transition to the molecular PDR (crossing the dissociation front (DF)). We use high-resolution near-IR integral field spectroscopic data from NIRSpec on JWST to observe the Orion Bar PDR as part of the PDRs4All JWST Early Release Science Program. The NIRSpec data reveal a forest of lines including, but not limited to, HeI, HI, and CI recombination lines, ionic lines, OI and NI fluorescence lines, Aromatic Infrared Bands (AIBs including aromatic CH, aliphatic CH, and their CD counterparts), CO2 ice, pure rotational and ro-vibrational lines from H2, and ro-vibrational lines HD, CO, and CH+, most of them detected for the first time towards a PDR. Their spatial distribution resolves the H and He ionisation structure in the Huygens region, gives insight into the geometry of the Bar, and confirms the large-scale stratification of PDRs. We observe numerous smaller scale structures whose typical size decreases with distance from Ori C and IR lines from CI, if solely arising from radiative recombination and cascade, reveal very high gas temperatures consistent with the hot irradiated surface of small-scale dense clumps deep inside the PDR. The H2 lines reveal multiple, prominent filaments which exhibit different characteristics. This leaves the impression of a "terraced" transition from the predominantly atomic surface region to the CO-rich molecular zone deeper in. This study showcases the discovery space created by JWST to further our understanding of the impact radiation from young stars has on their natal molecular cloud and proto-planetary disk, which touches on star- and planet formation as well as galaxy evolution.

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Els Peeters, Emilie Habart, Olivier Berne, Ameek Sidhu, Ryan Chown, Dries Van De Putte, Boris Trahin, Ilane Schroetter, Amelie Canin, Felipe Alarcon, Bethany Schefter, Baria Khan, Sofia Pasquini, Alexander G. G. M. Tielens, Mark G. Wolfire, Emmanuel Dartois, Javier R. Goicoechea, Alexandros Maragkoudakis, Takashi Onaka, Marc W. Pound, Silvia Vicente, Alain Abergel, Edwin A. Bergin, Jeronimo Bernard-Salas, Christiaan Boersma, Emeric Bron, Jan Cami, Sara Cuadrado, Daniel Dicken, Meriem Elyajour, Asuncion Fuente, Karl D. Gordon, Lina Issa, Christine Joblin, Olga Kannavou, Ozan Lacinbala, David Languignon, Romane Le Gal, Raphael Meshaka, Yoko Okada, Massimo Robberto, Markus Roellig, Thiebaut Schirmer, Benoit Tabone, Marion Zannese, Isabel Aleman, Louis Allamandola, Rebecca Auchettl, Giuseppe Antonio Baratta, Salma Bejaoui, Partha P. Bera, John H. Black, Francois Boulanger, Jordy Bouwman, Bernhard Brandl, Philippe Brechignac, Sandra Brunken, Mridusmita Buragohain, Andrew Burkhardt, Alessandra Candian, Stephanie Cazaux, Jose Cernicharo, Marin Chabot, Shubhadip Chakraborty, Jason Champion, Sean W. J. Colgan, Ilsa R. Cooke, Audrey Coutens, Nick L. J. Cox, Karine Demyk, Jennifer Donovan Meyer, Sacha Foschino, Pedro Garcia-Lario, Maryvonne Gerin, Carl A. Gottlieb, Pierre Guillard, Antoine Gusdorf, Patrick Hartigan, Jinhua He, Eric Herbst, Liv Hornekaer, Cornelia Jager, Eduardo Janot-Pacheco, Michael Kaufman, Sarah Kendrew, Maria S. Kirsanova, Pamela Klaassen, Sun Kwok, Alvaro Labiano, Thomas S. -Y. Lai, Timothy J. Lee, Bertrand Lefloch, Franck Le Petit, Aigen Li, Hendrik Linz, Cameron J. Mackie, Suzanne C. Madden, Joelle Mascetti, Brett A. McGuire, Pablo Merino. 2023-10-12. PDRs4All III: JWST's NIR spectroscopic view of the Orion Bar. https://doi.org/10.1051/0004-6361/202348244

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