Tracing extended low-velocity shocks through SiO emission Case study of the W43-MM1 ridge
Author
dc.contributor.author
Louvet, Fabien
Author
dc.contributor.author
Motte, F.
Author
dc.contributor.author
Gusdorf, A.
Author
dc.contributor.author
Lu'o'ng, Q. Nguyen
Author
dc.contributor.author
Lesaffre, P.
Author
dc.contributor.author
Duarte Cabral, A.
Author
dc.contributor.author
Maury, A.
Author
dc.contributor.author
Schneider, N.
Author
dc.contributor.author
Hill, T.
Author
dc.contributor.author
Schilke, P.
Author
dc.contributor.author
Gueth, F.
Admission date
dc.date.accessioned
2017-12-21T13:56:59Z
Available date
dc.date.available
2017-12-21T13:56:59Z
Publication date
dc.date.issued
2016
Cita de ítem
dc.identifier.citation
A&A 595, A122 (2016)
es_ES
Identifier
dc.identifier.issn
1432-0746
Identifier
dc.identifier.other
10.1051/0004-6361/201629077
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/146225
Abstract
dc.description.abstract
Aims. Previous literature suggests that the densest structures in the interstellar medium form through colliding flows, but patent evidence of this process is still missing. Recent literature proposes using SiO line emission to trace low-velocity shocks associated with cloud formation through collision. In this paper we investigate the bright and extended SiO(2 1) emission observed along the similar to 5 pc-long W43-MM1 ridge to determine its origin.
Methods. We used high angular resolution images of the SiO(2 1) and HCN(1 0) emission lines obtained with the IRAM plateau de Bure (PdBI) interferometer and combined with data from the IRAM 30m radiotelescope. These data were complemented by a Herschel column density map of the region. We performed spectral analysis of SiO and HCN emission line profiles to identify protostellar outflows and spatially disentangle two velocity components associated with low-and high-velocity shocks. Then, we compared the low-velocity shock component to a dedicated grid of one-dimensional (1D) radiative shock models.
Results. We find that the SiO emission originates from a mixture of high-velocity shocks caused by bipolar outflows and low-velocity shocks. Using SiO and HCN emission lines, we extract seven bipolar outflows associated with massive dense cores previously identified within the W43-MM1 mini-starburst cluster. Comparing observations with dedicated Paris-Durham shock models constrains the velocity of the low-velocity shock component from 7 to 12 km s(-1).
Conclusions. The SiO arising from low-velocity shocks spreads along the complete length of the ridge. Its contribution represents at least 45% and up to 100% of the total SiO emission depending on the area considered. The low-velocity component of SiO is most likely associated with the ridge formation through colliding flows or cloud-cloud collision