Issue |
A&A
Volume 638, June 2020
|
|
---|---|---|
Article Number | A7 | |
Number of page(s) | 8 | |
Section | Interstellar and circumstellar matter | |
DOI | https://doi.org/10.1051/0004-6361/202037815 | |
Published online | 29 May 2020 |
The role of Galactic H II regions in the formation of filaments
High-resolution submilimeter imaging of RCW 120 with ArTéMiS★
1
Aix Marseille Univ, CNRS, CNES, LAM,
Marseille,
France
e-mail: annie.zavagno@lam.fr
2
Institut Universitaire de France,
Paris,
France
3
Laboratoire d’Astrophysique (AIM), CEA/DRF, CNRS, Université Paris-Saclay, Université Paris Diderot,
Sorbonne Paris-Cité,
91191
Gif-sur-Yvette, France
4
Leibniz-Institut für Astrophysik Potsdam (AIP),
An der Sternwarte 16,
14482
Potsdam,
Germany
5
School of Physics & Astronomy, Cardiff University,
Cardiff
CF24 3AA,
UK
6
Department of Physics and Astronomy, Graduate School of Science and Engineering, Kagoshima University,
1-21-35 Korimoto, Kagoshima,
Kagoshima
890-0065,
Japan
7
Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP,
Rua das Estrelas,
PT4150-762
Porto,
Portugal
8
Laboratoire d’Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N,
allée Geoffroy Saint-Hilaire,
33615
Pessac, France
9
National Centre for Nuclear Research,
Ul. Pasteura 7,
02-093
Warsaw, Poland
10
Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, The University of Manchester,
Oxford Road,
Manchester
M13 9PL,
UK
11
Jeremiah Horrocks Institute, University of Central Lancashire,
Preston PR1 2HE, UK
12
Institut d’Astrophysique de Paris, Sorbonne Université, CNRS (UMR7095),
75014
Paris, France
13
I. Physik. Institut, University of Cologne,
50937
Cologne,
Germany
Received:
25
February
2020
Accepted:
6
April
2020
Context. Massive stars and their associated ionized (H II) regions could play a key role in the formation and evolution of filaments that host star formation. However, the properties of filaments that interact with H II regions are still poorly known.
Aims. To investigate the impact of H II regions on the formation of filaments, we imaged the Galactic H II region RCW 120 and its surroundings where active star formation takes place and where the role of ionization feedback on the star formation process has already been studied.
Methods. We used the large-format bolometer camera ArTéMiS on the APEX telescope and combined the high-resolution ArTéMiS data at 350 and 450 μm with Herschel-SPIRE/HOBYS data at 350 and 500 μm to ensure good sensitivity to a broad range of spatial scales. This allowed us to study the dense gas distribution around RCW 120 with a resolution of 8′′ or 0.05 pc at a distance of 1.34 kpc.
Results. Our study allows us to trace the median radial intensity profile of the dense shell of RCW 120. This profile is asymmetric, indicating a clear compression from the H II region on the inner part of the shell. The profile is observed to be similarly asymmetric on both lateral sides of the shell, indicating a homogeneous compression over the surface. On the contrary, the profile analysis of a radial filament associated with the shell, but located outside of it, reveals a symmetric profile, suggesting that the compression from the ionized region is limited to the dense shell. The mean intensity profile of the internal part of the shell is well fitted by a Plummer-like profile with a deconvolved Gaussian full width at half maximum of 0.09 pc, as observed for filaments in low-mass star-forming regions.
Conclusions. Using ArTéMiS data combined with Herschel-SPIRE data, we found evidence for compression from the inner part of the RCW 120 ionized region on the surrounding dense shell. This compression is accompanied with a significant (factor 5) increase of the local column density. This study suggests that compression exerted by H II regions may play a key role in the formation of filaments and may further act on their hosted star formation. ArTéMiS data also suggest that RCW 120 might be a 3D ring, rather than a spherical structure.
Key words: stars: formation / H II regions / ISM: individual objects: RCW 120 / submillimeter: ISM
© A. Zavagno et al. 2020
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.