Optical and infrared observations of the luminous quasar PDS 456: A radio-quiet analogue of 3C 273?
نویسندگان
چکیده
We present infrared photometry and optical and infrared spectroscopy of the recentlydiscovered, extremely luminous nearby quasar PDS 456. A number of broad emission features are seen in the near-infrared which we are unable to identify. We measure a more accurate redshift from a narrow forbidden emission line and compare the optical–infrared spectrum to that of 3C 273. The close similarity suggests that PDS 456 is a radio-quiet analogue of 3C 273, although radio observations do not support this idea.
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