Sub-arcsecond imaging of Arp 299-A at 150 MHz with LOFAR: Evidence for a starburst-driven outflow

DOI: 
10.1051/0004-6361/201732543
Publication date: 
21/03/2018
Main author: 
Ramírez-Olivencia N.
IAA authors: 
Ramírez-Olivencia, N.;Pérez-Torres, M.;Alberdi, A.;Pérez, E.
Authors: 
Ramírez-Olivencia N., Varenius E., Pérez-Torres M., Alberdi A., Pérez E., Alonso-Herrero A., Deller A., Herrero-Illana R., Moldón J., Barcos-Muñoz L., Martí-Vidal I.
Journal: 
Astronomy and Astrophysics
Refereed: 
Yes
Publication type: 
Article
Volume: 
610
Pages: 
L18
Number: 
L18
Abstract: 
We report on the first sub-arcsecond (0.44 × 0.41 arcsec2) 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 H2 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 Finally, we discuss unpublished Na I D spectra that confirm the outflow nature of this structure.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. © ESO 2018.
Database: 
SCOPUS
ADS
URL: 
https://ui.adsabs.harvard.edu/#abs/2018A&A...610L..18R/abstract
ADS Bibcode: 
2018A&A...610L..18R
Keywords: 
Galaxies; Galaxies star formation galaxies; Individual Arp 299; ISM jets and outflows; Radio continuum galaxies; Starburst