GMC Collisions as Triggers of Star Formation. V. Observational Signatures
Journal article, 2017

© 2017. The American Astronomical Society. All rights reserved.. We present calculations of molecular, atomic, and ionic line emission from simulations of giant molecular cloud (GMC) collisions. We post-process snapshots of the magnetohydrodynamical simulations presented in an earlier paper in this series by Wu et al. of colliding and non-colliding GMCs. Using photodissociation region (PDR) chemistry and radiative transfer, we calculate the level populations and emission properties of the transitions of 12 CO J = 1-0, [C i] at 609 μm, [C ii] 158 μm, and [O i] at 63 μm. From emission maps of integrated intensity and position-velocity diagrams, we find that fine-structure lines, particularly [C ii] 158 μm, can be used as a diagnostic tracer for cloud-cloud collision activity. These results hold even in more evolved systems in which the collision signature in molecular lines has been diminished.


magnetic fields - ISM

kinematics and dynamics - ISM

structure - methods

lines and bands - ISM

clouds - ISM



T.G. Bisbas

K.E.I. Tanaka

Jonathan Tan

Astronomy and Plasmaphysics

B. Wu

F. Nakamura

Astrophysical Journal

0004-637X (ISSN) 1538-4357 (eISSN)

Vol. 850 1 23-32

Subject Categories

Astronomy, Astrophysics and Cosmology


Basic sciences


Onsala Space Observatory



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