Multiphase Gas Interactions on Subarcsec Scales in the Shocked Intergalactic Medium of Stephan's Quintet with JWST and ALMA
Abstract
We combine James Webb Space Telescope (JWST) and Hubble Space Telescope imaging with Atacama Large Millimeter Array CO(2–1) spectroscopy to study the highly turbulent multiphase intergalactic medium (IGM) in Stephan's Quintet on 25–150 pc scales. Previous Spitzer observations revealed luminous H2 line cooling across a 45 kpc-long filament, created by a giant shock wave, following the collision with an intruder galaxy, NGC 7318b. We demonstrate that the Mid-Infrared Instrument/F1000W/F770W filters are dominated by 0–0 S(3) H2 and a combination of polycyclic aromatic hydrocarbon and 0–0 S(5) H2 emission. These observations reveal the dissipation of kinetic energy as massive clouds experience collisions, interactions, and likely destruction/recycling within different phases of the IGM. In 1 kpc-scaled structure, warm H2 was seen to form a triangular-shaped head and tail of compressed and stripped gas behind a narrow shell of cold H2. In another region, two cold molecular clumps with very different velocities are connected by an arrow-shaped stream of warm, probably shocked, H2 suggesting a cloud–cloud collision is occurring. In both regions, a high warm-to-cold molecular gas fraction indicates that the cold clouds are being disrupted and converted into warm gas. We also map gas associated with an apparently forming dwarf galaxy. We suggest that the primary mechanism for exciting strong mid-IR H2 lines throughout Stephan's Quintet is through a fog of warm gas created by the shattering of denser cold molecular clouds and mixing/recycling in the post-shocked gas. A full picture of the diverse kinematics and excitation of the warm H2 will require future JWST mid-IR spectroscopy. The current observations reveal the rich variety of ways that different gas phases can interact with one another.
Additional Information
© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. We acknowledge the remarkable dedication of the scientists and engineers who made the JWST possible, and especially the Early Release Observation (ERO) science team, upon which some of our paper is based. This work is based, in part, on observations made with the NASA/ESA/CSA JWST. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. These observations are associated with program #2732. This paper makes use of ALMA data from program ID: 2015.1.000241.S (PI: P. Guillard). ALMA is a partnership of ESO (representing its member states), the NSF (USA), and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by the ESO, AUI/NRAO, and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. E.O'S. acknowledges support from NASA through Chandra Award Number GO8-19112A. P.G. would like to thank the Sorbonne University, the Institut Universitaire de France, the Centre National d'Etudes Spatiales (CNES), the "Programme National de Cosmologie and Galaxies" (PNCG) and the "Physique Chimie du Milieu Interstellaire" (PCMI) programs of CNRS/INSU, with INC/INP cofunded by CEA and CNES, for their financial support. We would like to thank an anonymous referee for very helpful comments on the manuscript.Attached Files
Published - Appleton_2023_ApJ_951_104.pdf
Files
Name | Size | Download all |
---|---|---|
md5:b445919979ec70e7efe93565d7d7189c
|
3.2 MB | Preview Download |
Additional details
- Eprint ID
- 122562
- Resolver ID
- CaltechAUTHORS:20230727-911770600.6
- NAS 5-03127
- NASA
- GO8-19112A
- NASA
- Created
-
2023-08-14Created from EPrint's datestamp field
- Updated
-
2023-08-14Created from EPrint's last_modified field
- Caltech groups
- Infrared Processing and Analysis Center (IPAC)