A single radio-emitting nucleus in the dual AGN candidate NGC 5515

Abstract

The Seyfert galaxy NGC 5515 has double-peaked narrow-line emission in its optical spectrum, and it has been suggested that this could indicate that it has two active nuclei. We observed the source with high-resolution very long baseline interferometry at two radio frequencies, reduced archival Very Large Array data, and re-analysed its optical spectrum. We detected a single, compact radio source at the position of NGC 5515, with no additional radio emission in its vicinity. The optical spectrum of the source shows that the blue and red components of the double-peaked lines have very similar characteristics. While we cannot rule out unambiguously thatNGC5515 harbours a dualAGN, the assumption of a singleAGNprovides amore plausible explanation for the radio observations and the optical spectrum. © 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.