Volume 556, August 2013
|Number of page(s)||9|
|Section||Interstellar and circumstellar matter|
|Published online||02 August 2013|
Large-scale mapping of the massive star-forming region RCW38 in the [CII] and PAH emission
1 Graduate School of Science, Nagoya University, Chikusa-ku, 464-8602 Nagoya, Japan
2 Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, 252-5210 Kanagawa, Japan
3 Tata Institute of Fundamental Research, Homi Bhabha Road, 400005 Mumbai, India
4 Department of Astronomy, Graduate School of Science, University of Tokyo, Bunkyo-ku, 113-0033 Tokyo, Japan
Received: 1 April 2013
Accepted: 5 June 2013
Aims. We investigate the large-scale structure of the interstellar medium (ISM) around the massive star cluster RCW 38 in the [CII] 158 μm line and polycyclic aromatic hydrocarbon (PAH) emission.
Methods. We carried out [CII] line mapping of an area of ~30′ × 15′ for RCW 38 by a Fabry-Perot spectrometer on a 100 cm balloon-borne telescope with an angular resolution of . We compared the [CII] intensity map with the PAH and dust emission maps obtained by the AKARI satellite.
Results. The [CII] emission shows a highly nonuniform distribution around the cluster, exhibiting the structure widely extended to the north and the east from the center. The [CII] intensity rapidly drops toward the southwest direction, where a CO cloud appears to dominate. We decompose the 3–160 μm spectral energy distributions of the surrounding ISM structure into PAH as well as warm and cool dust components with the help of 2.5–5 μm spectra.
Conclusions. We find that the [CII] emission spatially corresponds to the PAH emission better than to the dust emission, confirming the relative importance of PAHs for photo-electric heating of gas in photo-dissociation regions. A naive interpretation based on our observational results indicates that molecular clouds associated with RCW 38 are located both on the side of and behind the cluster.
Key words: dust, extinction / infrared: ISM / ISM: structure / ISM: clouds
© ESO, 2013
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.