HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

The B1 shock in the L1157 outflow as seen at high spatial resolution

Abstract : We present high spatial resolution (750 au at 250 pc) maps of the B1 shock in the blue lobe of the L1157 outflow in four lines: CS (3-2), CH3OH (3K-2K), HC3N (16-15) and p-H2CO (202-301). The combined analysis of the morphology and spectral profiles has shown that the highest velocity gas is confined in a few compact (≈5 arcsec) bullets, while the lowest velocity gas traces the wall of the gas cavity excavated by the shock expansion. A large velocity gradient model applied to the CS (3-2) and (2-1) lines provides an upper limit of 106 cm-3 to the averaged gas density in B1 and a range of 5 × 10^3≤ n_H_2 ≤ 5 × 10^5 cm-3 for the density of the high-velocity bullets. The origin of the bullets is still uncertain: they could be the result of local instabilities produced by the interaction of the jet with the ambient medium or could be clumps already present in the ambient medium that are excited and accelerated by the expanding outflows. The column densities of the observed species can be reproduced qualitatively by the presence in B1 of a C-type shock and only models where the gas reaches temperatures of at least 4000 K can reproduce the observed HC3N column density.
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03614203
Contributor : Nathalie Pothier Connect in order to contact the contributor
Submitted on : Sunday, March 20, 2022 - 8:53:39 AM
Last modification on : Monday, March 21, 2022 - 3:35:29 AM

File

stt1559.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Collections

Citation

M. Benedettini, S. Viti, C. Codella, F. Gueth, A. I. Gómez-Ruiz, et al.. The B1 shock in the L1157 outflow as seen at high spatial resolution. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2013, 436, pp.179-190. ⟨10.1093/mnras/stt1559⟩. ⟨insu-03614203⟩

Share

Metrics

Record views

42

Files downloads

2