A QUASAR WITH ULTRASTRONG, ULTRAVIOLET FE-II EMISSION

We report the discovery of an unusual quasar, 2226-3905, found during a survey of quasar candidates. The ultraviolet spectrum (intrinsic fra me) of the object is dominated by extremely strong Fe II emission. The emission lines are narrow (typical FWHM similar to 2150 km s(-1)) and show little trace of their usually broad wings. C III] lambda 1909 ap pears to be blended with an Fe III multiplet and we identify Fe II lin es originating from high-energy levels (similar to 10 eV). We consider two possible explanations: either the quasar is a low-ionization broa d absorption line (BAL) quasar in which the sight-line does not inters ect any BAL clouds or Ly alpha fluorescence is the main physical proce ss involved in the formation of Fe II. Our observations do not favour the BAL interpretation, but rather support the latter process. Higher resolution observations would give definite support to the Ly alpha fl uorescence.