Investigation of radio objects with continuous optical spectra. The search for spectral features with the 6-meter telescope

The results of spectral observations with the help of the 1000-channel photon counter on the 6-meter telescope of 13 radio objects with continuous optical spectra (ROCOSes) are presented. The data obtained are in agreement with the hypothesis that these ROCOSes are BL Lac-type objects with luminosities in the Mg II 2798 line which do not exceed or are comparable with those of the known lacertae objects. The wide emission lines with contrasts of 0.2-0.3 have been surely detected in the spectra of the 4 ''faint'' ROCOSes (m=18.5-19) with normal steep radio spectra up to cm wavelengths. The redshifts, equivalent widths and halfwidths of the lines are determined, the absolute magnitudes and luminosities in the lines are estimated. Two of these objects are renked to radio quasars and another two may be classified as active galactic nuclei which are intermediate between blazars and ordinary radio quasars