AREA SPECTROSCOPY OF THE EXTENDED EMISSION-LINE REGION IN THE SEYFERT-GALAXY NGC-3516

We performed an area spectroscopic observation of the extended emissio n-line region (EELR) in the Seyfert 1 galaxy NGC 3516 with the Spectro nebulagraph of Okayama Astrophysical Observatory. The whole EELR, incl uding the northern detached component which lies apart by 20'' (4 kpc) from the nucleus, was scanned with a 4.'5 long slit. From the resulti ng data cube we reproduced pure narrow emission-line images of Hbeta, [O III], Halpha, [N II], and [S II]. From these images it has been fou nd that the excitation is higher toward the northern detached componen t from the nucleus, and probably also toward the opposite direction. T he norhtern detached component is ionized by power-law ionizing radiat ion as well as a Z-shaped component. From the kinematics, the northern detached component lies on the galactic disk. There is a considerable deficit of ionizing photons toward the line of site in spite of the f act that the broad-line region can be clearly seen from us. It seems t hat collimation of the ionizing radiation from the nucleus is caused i n or inside the broad line region. Thus, a simple version of the curre nt unified scheme of Seyfert nuclei may not apply to this typical Seyf ert 1 galaxy, as in the case of the NGC 4151.