IUE observations of the quasar 3C 273.
Boggess, A.; Lane, A. L.; Oke, J. B.; Zimmerman, B.; Torres-Peimbert, S.; Daltabuit, E.; Estabrook, F. B.; Wahlquist, H. D.; Green, R.; Schmidt, O. M.; Morton, D. C.; Roeder, R. C.
United States, Mexico
Abstract
IUE observations indicate that the spectrum of 3C 273 is similar to that of other large-redshift quasars. There is a large excess of flux in the range 2400 A to 5300 A, which encompasses the Balmer jump region but which does not appear to be explainable by Balmer emission. The intensity ratio of Lyman-alpha to H-beta is 5.5, in agreement with other measures and a factor 6 smaller than the recombination value. The only absorption lines in the spectrum are due to our Galaxy. There is marginal evidence for a depression of the continuum shortward of the Lyman-alpha emission line, but the errors are too large to warrant any conclusion that 3C 273 has a rich absorption-line spectrum such as that seen in large-redshift quasars. The absence of emission and absorption lines of Fe II leads to the conclusion that resonance fluorescence probably produces the visual Fe II emission lines.