| Title: |
SQ-A: A Collision-triggered Starburst in the Intragroup Medium of Stephan’s Quintet |
| Authors: |
Xu, C, K; Cheng, C.; Yun, M, S; Appleton, P, N; Emonts, B, H C; Braine, J.; Gallagher, S, C; Guillard, P.; Lisenfeld, U.; O’sullivan, E.; Renaud, F.; Aromal, P.; Duc, P.-A.; Labiano, A.; Togi, A. |
| Contributors: |
Chinese Academy of Sciences South America Center for Astronomy, National Astronomical Observatories, CAS, Beijing 100101, Peopleʼs Republic of China; National Astronomical Observatories Beijing (NAOC); Chinese Academy of Sciences Beijing (CAS); University of Massachusetts Amherst (UMass Amherst); University of Massachusetts System (UMASS); Infrared Processing and Analysis Center (IPAC); California Institute of Technology (CALTECH); National Radio Astronomy Observatory Charlottesville (NRAO); National Radio Astronomy Observatory (NRAO); Laboratoire d'Astrophysique de Bordeaux Pessac (LAB); Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS); Institute for Earth and Space Exploration, Western University, 1151 Richmond St., London, ON N6A 3K7, Canada; Institut d'Astrophysique de Paris (IAP); Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS); Institut universitaire de France (IUF); Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.); Universidad de Granada = University of Granada (UGR); Instituto Carlos I de Fisica Teorica y Computacional; Harvard-Smithsonian Center for Astrophysics (CfA); Harvard University-Smithsonian Institution; Observatoire astronomique de Strasbourg (ObAS); Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS); European Space Astronomy Centre (ESAC); Agence Spatiale Européenne = European Space Agency (ESA); Texas State University; Académie chinoise des sciences (CAS), subvention accordée au Centre d'astronomie sud-américain de la CAS; NSFC, subventions n° 11803044 et 12173045; Programme spatial habité chinois (CMS-CSST-2025-A07); Subventions de recherche PID2020-114414GB-I00 et PID2023-150178NB-I00, financées par MCIU/AEI/10.13039/501100011033 et par la subvention FQM108 de la Junta de Andalucía (Espagne); Agence spatiale canadienne et le Conseil de recherches en sciences naturelles et en génie; Association of Universities for Research in Astronomy, Inc., contrat NASA NAS 5-03127 pour le JWST et contrat NASA NAS5-26555; Bureau des sciences spatiales de la NASA, subvention NAG5-7584; Fondation nationale danoise pour la recherche (DNRF140), Centre Cosmic Dawn (DAWN); ALMA |
| Source: |
ISSN: 0004-637X. |
| Publisher Information: |
CCSD; American Astronomical Society |
| Publication Year: |
2025 |
| Subject Terms: |
Hickson compact group; Star formation; H I line emission; Shocks; Galaxy collisions; Galaxy groups; Millimeter astronomy; Interacting galaxies; Intergalactic medium; Circumgalactic medium; [SDU]Sciences of the Universe [physics] |
| Time: |
802; 1569; 690; 2086; 585; 597; 1061; 813; 1879; 729 |
| Description: |
International audience ; We present new observational evidence supporting the hypothesis that SQ-A, a starburst in the intragroup medium (IGrM) of Stephan's Quintet (SQ), is triggered by a high-speed collision between two gas systems, one associated with the IGrM (v ∼ 6900 km s -1 ) and another with the intruder galaxy NGC 7318b (v ∼ 6000 km s -1 ). The new CO(2-1) data set from the Atacama Large Millimeter/submillimeter Array has angular resolutions between 0 . 2 and 7 . 0 and the new Very Large Array H I data cube has an angular resolution of × 6 . 6 7 . 9. The CO maps show that the two gas systems are bridged by another system with an intermediate velocity of ∼6600 km s -1 , whereas the H I data show that the component of v ∼ 6600 km s -1 fits well into a gap in the more extended v ∼ 6000 km s -1 component, albeit with a displacement of ∼5 kpc. Both the bridge and the complementary distributions between different gas systems are common features of starbursts triggered by cloud-cloud collision. An analysis of clumps (sizes of 100-200 pc) reveals very diversified star formation (SF) activity in clumps belonging to different kinematic systems, with the molecular gas depletion time of the v ∼ 6900 km s -1 clumps being more than 10 times longer than that of the v ∼ 6600 km s -1 clumps. The results are consistent with a scenario in which the enhanced SF activity (and the starburst) in the system of v ∼ 6600 km s -1 is due to gas compression generated in cloud-cloud collisions, whereas the suppression of SF in the v ∼ 6900 km s -1 system is due to vortices (i.e. gas rotation) generated in more complex collisions involving dense clouds and diffuse intercloud gas associated with high-speed shocks. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.3847/1538-4357/adfbf6 |
| Availability: |
https://insu.hal.science/insu-05301569; https://insu.hal.science/insu-05301569v1/document; https://insu.hal.science/insu-05301569v1/file/Xu_2025_ApJ_991_197.pdf; https://doi.org/10.3847/1538-4357/adfbf6 |
| Rights: |
https://creativecommons.org/licenses/by/4.0/ ; info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.C03A29CD |
| Database: |
BASE |