The Ly-alpha and C IV lines in 10 low-redshift active galactic nuclei/quasars.

We analyze the properties of the Ly α and C IV lines in 10 active galaxy nuclei/quasars with z < 0.2, for which relatively high quality spectra can be found in the first installment of the IUE "Uniform Low Dispersion Archives". A simple profile fitting of Ly α and of C IV with 2 gaussian components of different widths leads to the following results: (a) The line intensity ratio C IV/Ly α is often larger in the fast moving gas producing the wings, than it is at the line center. (b) When the wavelengths of the two gaussian components are left free in the fits, the wavelengths of the two components agree with each other within +/- 2 A, indicating the absence of systematic asymmetry of Ly α and of C IV. Moreover, when the spectra are aligned on the peak of Ly α, the wavelength of C IV falls at 1549.2 A as expected in the absence of a systematic line shift of C IV with respect to Ly α. There are 2 exceptions to these results: the strongly blue asymmetric C IV line in I Zw 1, and the weakness of the narrow component of Ly α in 0804+76.