Query : 2017A&A...608A.102G

2017A&A...608A.102G - Astronomy and Astrophysics, volume 608A, 102-102 (2017/12-1)

Squeezed between shells? The origin of the Lupus I molecular cloud. II. APEX CO and GASS H I observations.


Abstract (from CDS):

Context. LupusI cloud is found between the Upper Scorpius (USco) and Upper Centaurus-Lupus (UCL) subgroups of the Scorpius-Centaurus OB association, where the expanding USco HI shell appears to interact with a bubble currently driven by the winds of the remaining B stars of UCL.
Aims. We investigate whether the LupusI molecular could have formed in a colliding flow, and in particular, how the kinematics of the cloud might have been influenced by the larger scale gas dynamics.
Methods. We performed APEX 13CO(2-1)and C18O(2-1) line observations of three distinct parts of LupusI that provide kinematic information on the cloud at high angular and spectral resolution. We compare those results to the atomic hydrogen data from the GASS HI survey and our dust emission results presented in the previous paper. Based on the velocity information, we present a geometric model for the interaction zone between the USco shell and the UCL wind bubble.
Results. We present evidence that the molecular gas of Lupus Iis tightly linked to the atomic material of the USco shell. The CO emission in Lupus Iis found mainly at velocities between vLSR=3-6km/s, which is in the same range as the HI velocities. Thus, the molecular cloud is co-moving with the expanding USco atomic HI shell. The gas in the cloud shows a complex kinematic structure with several line-of-sight components that overlay each other. The nonthermal velocity dispersion is in the transonic regime in all parts of the cloud and could be injected by external compression. Our observations and the derived geometric model agree with a scenario in which Lupus I is located in the interaction zone between the USco shell and the UCL wind bubble.
Conclusions. The kinematics observations are consistent with a scenario in which the Lupus Icloud formed via shell instabilities. The particular location of LupusI between USco and UCL suggests that counterpressure from the UCL wind bubble and pre-existing density enhancements, perhaps left over from the gas stream that formed the stellar subgroups, may have played a role in its formation.

Abstract Copyright: © ESO, 2017

Journal keyword(s): ISM: bubbles - ISM: clouds - ISM: kinematics and dynamics - ISM: structure - ISM: molecules - radio lines: ISM - radio lines: ISM

VizieR on-line data: <Available at CDS (J/A+A/608/A102): list.dat fits/*>

Simbad objects: 8

goto Full paper

goto View the references in ADS

Number of rows : 8
N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
1 LDN 1517 DNe 04 55 45 +30 33.0           ~ 111 0
2 NAME Upper Centaurus Lupus As* 15 24 -41.9           ~ 433 1
3 Lupus 1 Cld 15 43 02.1 -34 09 06           ~ 264 0
4 NAME Lupus Complex SFR 16 03 -38.1           ~ 643 0
5 NAME Upper Sco Association As* 16 12 -23.4           ~ 1252 1
6 NAME Upper Sco-Cen As* 16 15 -24.2           ~ 1267 1
7 NAME Ophiuchus Molecular Cloud SFR 16 28 06 -24 32.5           ~ 3446 1
8 NAME Galactic Center reg 17 45 39.60213 -29 00 22.0000           ~ 13437 0

To bookmark this query, right click on this link: simbad:objects in 2017A&A...608A.102G and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact