Near-IR spectroscopy of PKS1549-79: a proto-quasar revealed?
نویسندگان
چکیده
We present a near-IR spectrum of the nearby radio galaxy PKS1549-79 (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), 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 debris left over from the triggering events has not yet been swept aside by circumnuclear outflows.
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