SiO emission as a probe of cloud-cloud collisions in infrared dark clouds
Journal article, 2020

Infrared dark clouds (IRDCs) are very dense and highly extincted regions that host the initial conditions of star and stellar cluster formation. It is crucial to study the kinematics and molecular content of IRDCs to test their formation mechanism and ultimately characterize these initial conditions. We have obtained high-sensitivity Silicon Monoxide, SiO(2-1), emission maps towards the six IRDCs, G018.82-00.28, G019.27+00.07, G028.53-00.25, G028.67+00.13, G038.95-00.47, and G053.11+00.05 (cloud A, B, D, E, I, and J, respectively), using the 30-m antenna at the Instituto de Radioastronomia Millimetrica (IRAM30m). We have investigated the SiO spatial distribution and kinematic structure across the six clouds to look for signatures of cloud-cloud collision events that may have formed the IRDCs and triggered star formation within them. Towards clouds A, B, D, I, and J, we detect spatially compact SiO emission with broad-line profiles that are spatially coincident with massive cores. Towards the IRDCs A and I, we report an additional SiO component that shows narrow-line profiles and that is widespread across quiescent regions. Finally, we do not detect any significant SiO emission towards cloud E. We suggest that the broad and compact SiO emission detected towards the clouds is likely associated with ongoing star formation activity within the IRDCs. However, the additional narrow and widespread SiO emission detected towards cloud A and I may have originated from the collision between the IRDCs and flows of molecular gas pushed towards the clouds by nearby H II regions.

ISM: kinematics and dynamics

ISM: clouds

ISM: molecules

ISM: individual objects: G018.82-00.28, G019.27+00.07, G028.53-00.25, G028.67+00.13, G038.95-00.47, G053.11+00.05

H II regions

Author

Giuliana Cosentino

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

I Jimenez-Serra

Spanish Astrobiology Center (INTA-CSIC)

J. D. Henshaw

Max Planck Society

P. Caselli

Max Planck Society

S. Viti

University College London (UCL)

A. T. Barnes

University of Bonn

Jonathan Tan

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

F. Fontani

Istituto nazionale di astrofisica (INAF)

B. Wu

National Astronomical Observatory of Japan

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 499 2 1666-1681

Subject Categories

Meteorology and Atmospheric Sciences

Astronomy, Astrophysics and Cosmology

Atom and Molecular Physics and Optics

DOI

10.1093/mnras/staa2942

More information

Latest update

9/15/2023