Open AccessNear‐infrared spectroscopy of PKS 1549−79: a protoquasar revealed?
Author(s) -
Bellamy M. J.,
Tadhunter C. N.,
Morganti R.,
Wills K. A.,
Holt J.,
Taylor M. D.,
Watson C. A.
Publication year - 2003
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2003.07078.x
Subject(s) - physics , astrophysics , quasar , astronomy , galaxy , emission spectrum , point source , spectroscopy , luminous infrared galaxy , infrared , accretion disc , line of sight , radio galaxy , spectral line , optics
We present a near‐infrared (near‐IR) spectrum of the nearby radio galaxy PKS 1549−79 ( z = 0.153) . These data were taken with the aim of testing the idea that this object contains a quasar nucleus that is moderately extinguished, despite evidence that its radio jet points close to our line of sight. We detect broad Paα emission (FWHM 1745 ± 40 km s −1 ) , relatively bright continuum emission, and a continuum slope consistent with a reddened quasar spectrum (3.1 < A V < 7.3) , all emitted by an unresolved point source. Therefore we conclude that we have, indeed, detected a hidden quasar nucleus in PKS 1549−79. Combined with previous results, these observations are consistent with the idea that PKS 1549−79 is a young radio source in which the cocoon of debris left over from the triggering events has not yet been swept aside by circumnuclear outflows.