Multifrequency observations of the quasi-stellar object Ton 1542.

The authors present single-epoch multifrequency data for the radio-quiet low-redshift QSO Ton 1542, spanning radio through ultraviolet wavelengths. They measure a 3σ upper limit of 9.2 mJy for the 20.3 GHz flux density. The first ultraviolet spectrum of this object is presented and discussed. The authors find a particularly strong excess of flux density at ≡3000 Å, which is likely to be dominated by Balmer continuum emission. They also find a Lα/Hβ flux ratio of ≡17, which is higher than that usually observed in QSOs.