Sub-arcsecond imaging of Arp 299-A at 150 MHz with LOFAR: Evidence for a starburst-driven outflow
Artikel i vetenskaplig tidskrift, 2018

We report on the first sub-arcsecond (0.44 × 0.41 arcsec 2 ) angular resolution image at 150 MHz of the A-nucleus in the luminous infrared galaxy Arp 299, from International Low Frequency Array (LOFAR) Telescope observations. The most remarkable finding is that of an intriguing two-sided, filamentary structure emanating from the A-nucleus, which we interpret as an outflow that extends up to at least 14 arcsec from the A-nucleus in the N-S direction (≈5 kpc deprojected size) and accounts for almost 40% of the extended emission of the entire galaxy system. We also discuss HST/NICMOS [FeII] 1.64 μm and H 2 2.12 μm images of Arp 299-A, which show similar features to those unveiled by our 150 MHz LOFAR observations, providing strong morphological support for the outflow scenario. Finally, we discuss unpublished Na I D spectra that confirm the outflow nature of this structure. From energetic arguments, we rule out the low-luminosity active galactic nucleus in Arp 299-A as a driver for the outflow. On the contrary, the powerful, compact starburst in the central regions of Arp 299-A provides plenty of mechanical energy to sustain an outflow, and we conclude that the intense supernova (SN) activity in the nuclear region of Arp 299-A is driving the observed outflow. We estimate that the starburst wind can support a mass-outflow rate in the range (11-63 M ⊙ yr -1 ) at speeds of up to 370-890 km s -1 , and is relatively young, with an estimated kinematic age of 3-7 Myr. Those results open an avenue to the use of low-frequency (150 MHz), sub-arcsecond imaging with LOFAR to detect outflows in the central regions of local luminous infrared galaxies.

Galaxies star formation galaxies

Individual Arp 299

ISM jets and outflows

Radio continuum galaxies




Naim Ramirez-Olivencia

CSIC - Instituto de Astrofísica de Andalucía (IAA)

Eskil Varenius

University of Manchester

M.A. Pérez-Torres

Universidad de Zaragoza

CSIC - Instituto de Astrofísica de Andalucía (IAA)

Antxon Alberdi

CSIC - Instituto de Astrofísica de Andalucía (IAA)

E. Pérez

CSIC - Instituto de Astrofísica de Andalucía (IAA)

A. Alonso-Herrero

CSIC-INTA - Centro de Astrobiologia (CAB)

A. Deller

Swinburne University of Technology

R. Herrero-Illana

European Southern Observatory Santiago

J. Moldon

University of Manchester

Loreto Barcos-Munoz

Atacama Large Millimeter-submillimeter Array (ALMA)

National Radio Astronomy Observatory

Ivan Marti-Vidal

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium, Onsala rymdobservatorium, Observationssupport

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 610 L18


Astronomi, astrofysik och kosmologi

Atom- och molekylfysik och optik

Medicinsk bildbehandling