Outflows from Super Star Clusters in the Central Starburst of NGC 253
Journal article, 2021

Young massive clusters play an important role in the evolution of their host galaxies, and feedback from the high-mass stars in these clusters can have profound effects on the surrounding interstellar medium. The nuclear starburst in the nearby galaxy NGC 253 at a distance of 3.5 Mpc is a key laboratory in which to study star formation in an extreme environment. Previous high-resolution (1.9 pc) dust continuum observations from the Atacama Large Millimeter/submillimeter Array (ALMA) discovered 14 compact, massive super star clusters (SSCs) still in formation. We present here ALMA data at 350 GHz with 28 mas (0.5 pc) resolution. We detect blueshifted absorption and redshifted emission (P-Cygni profiles) toward three of these SSCs in multiple lines, including CS 7-6 and (HCN)-C-13 4-3, which represent direct evidence for previously unobserved outflows. The mass contained in these outflows is a significant fraction of the cluster gas masses, which suggests we are witnessing a short but important phase. Further evidence of this is the finding of a molecular shell around the only SSC visible at near-IR wavelengths. We model the P-Cygni line profiles to constrain the outflow geometry, finding that the outflows must be nearly spherical. Through a comparison of the outflow properties with predictions from simulations, we find that none of the available mechanisms completely explains the observations, although dust-reprocessed radiation pressure and O star stellar winds are the most likely candidates. The observed outflows will have a very substantial effect on the clusters' evolution and star formation efficiency.

Author

Rebecca C. Levy

University of Maryland

Alberto D. Bolatto

University of Maryland

Adam K. Leroy

Ohio State University

Kimberly L. Emig

Leiden University

National Radio Astronomy Observatory

Mark Gorski

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Nico Krieger

Max Planck Society

Laura Lenkic

University of Maryland

David S. Meier

National Radio Astronomy Observatory Socorro

New Mexico Institute of Mining and Technology

Elisabeth A. C. Mills

University of Kansas

Juergen Ott

National Radio Astronomy Observatory Socorro

Erik Rosolowsky

University of Alberta

Elizabeth Tarantino

University of Maryland

Sylvain Veilleux

University of Maryland

Fabian Walter

Max Planck Society

National Radio Astronomy Observatory Socorro

Axel Weiss

Max Planck Society

Martin A. Zwaan

European Southern Observatory Santiago

Astrophysical Journal

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

Vol. 912 1 4

Subject Categories

Meteorology and Atmospheric Sciences

Astronomy, Astrophysics and Cosmology

Atom and Molecular Physics and Optics

DOI

10.3847/1538-4357/abec84

More information

Latest update

5/17/2021