EVN imaging of the LIRGI sample
Konferensbidrag (offentliggjort, men ej förlagsutgivet), 2014
The central few hundred parsecs of Ultra/Luminous Infrared Galaxies (U/LIRGs) are hidden from view at most wavelengths due to the presence of large amounts of dust. Very Long Baseline Interferometry (VLBI) observations are a powerful tool to unveil the nature of the sources beyond dust clouds. In fact, radio observations are unaffected by dust, and thanks to the high angular resolution are able to pinpoint the compact components in the central regions of U/LIRGs. Thus, VLBI observations can potentially disentangle the dominant mechanism responsible for the dust heating in U/LIRGs, i.e., an Active Galactic Nucleus (AGN), or a starburst, or a combination of both. In this contribution we present preliminary results for 12 galaxies from the Luminous Infrared Galaxy Inventory (LIRGI) sample, obtained from observations with the European VLBI Network (EVN) at 6 and 18 cm. We show images from NGC 2623 and Mrk 331. Mrk 331 shows three relatively faint compact components at C-band, consistent with emission from young supernovae and/or supernova remnants. On the contrary, NGC 2623 shows a single, very bright compact component at both wavelengths and a very inverted spectral index, clearly indicating that this is the AGN. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.