Fast, Collimated Outflow in the Western Nucleus of Arp 220
Journal article, 2018

We present the first spatially and spectrally resolved image of the molecular outflow in the western nucleus of Arp 220. The outflow, seen in HCN (1-0) by the Atacama Large millimeter/sub-millimeter Array, is compact and collimated, with an extension ≲120 pc. Bipolar morphology emerges along the minor axis of the disk, with redshifted and blueshifted components reaching a maximum inclination-corrected velocity of km s -1 . The outflow is also seen in CO and continuum emission, the latter implying that it carries significant dust. We estimate a total mass in the outflow of , a dynamical time of ∼10 5 yr, and mass outflow rates of yr -1 and yr -1 for the northern and southern lobes, respectively. Possible driving mechanisms include supernovae energy and momentum transfer, radiation pressure feedback, and a central AGN. The latter could explain the collimated morphology of the HCN outflow; however, we need more complex theoretical models, including contributions from supernovae and AGN, to pinpoint the driving mechanism of this outflow.

galaxies: starburst

galaxies: active

galaxies: interactions

galaxies: individual (Arp220)

Author

Loreto Barcos-Munoz

Atacama Large Millimeter-submillimeter Array (ALMA)

National Radio Astronomy Observatory

Susanne Aalto

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Todd A. Thompson

Ohio State University

K. Sakamoto

Academia Sinica

Sergio Martín

Atacama Large Millimeter-submillimeter Array (ALMA)

European Southern Observatory Santiago

Adam K. Leroy

Ohio State University

G. Privon

University of Florida

Pontificia Universidad Catolica de Chile

A. S. Evans

National Radio Astronomy Observatory

University of Virginia

Amanda Kepley

National Radio Astronomy Observatory

Astrophysical Journal Letters

2041-8205 (ISSN) 2041-8213 (eISSN)

Vol. 853 2 L28

Subject Categories

Astronomy, Astrophysics and Cosmology

Atom and Molecular Physics and Optics

Theoretical Chemistry

DOI

10.3847/2041-8213/aaa28d

More information

Latest update

4/12/2018