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Near-IR spectroscopy of PKS1549-79: a proto-quasar revealed?

M. J. Bellamy·C. N. Tadhunter·R. Morganti·K. A. Wills·J. Holt·M. D. Taylor·C. A. Watson
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Abstract

We present a near-IR spectrum of the nearby radio galaxy PKS1549-79 (z=0153). 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 Paschen Alpha emission (FWHM ~1745 km/s), relatively bright continuum emission, and a continuum slope consistent with a reddened quasar spectrum (3.1 < Av < 7.3), all emitted by an unresolved point source. Therefore we conclude that we have, indeed, detected a hidden quasar nucleus in PKS1549-79. Combined with previous results, these observations are consistent with the idea that PKS1549-79 is a young radio source in which the cocoon of debric left over from the triggering events has not yet been swept aside by circumnuclear outflows.

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M. J. Bellamy, C. N. Tadhunter, R. Morganti, K. A. Wills, J. Holt, M. D. Taylor, C. A. Watson. 2003-08-20. Near-IR spectroscopy of PKS1549-79: a proto-quasar revealed?. https://doi.org/10.1046/j.1365-8711.2003.07078.x

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