We present a compilation of radio, infrared, optical and hard X-ray (2-10kev) data for a sample of 90 Seyfert 2 galaxies(Sy2s) with spectropolarimetric observations (41 Sy2s with detection of polarized broad lines (PBL) and 49 without PBL). Compared to Sy2s without PBL, Sy2s with PBL tend to be earlier-type spirals, and show warmer mid-infrared color and significant excess of emissions (including the hard X-ray(2-10kev), [O {\sc iii}]$\lambda$5007, infrared (25 $\mu$m) and radio). Our analyses indicate that the majority of Sy2s without PBL are those sources having less powerful AGN activities, most likely caused by low accretion rate. It implies that the detectability of the polarized broad emission lines in Sy2s may depend on their central AGN activities in most cases. Based on the available data, we find no compelling evidence for the presence of two types of Sy2s, one type of them has been proposed to be intrinsically different from Sy2s claimed in Unification Model.Comment: 24 pages, 6 figures, accepted for publication in Ap

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Abstract. We present our recent spectrophotometric results of the infrared luminous Seyfert 2 galaxy NGC 7679. We find compelling evidence for the presence of a recent nuclear starburst, revealed by the observations of a) the spectral features of high order Balmer absorption lines, b) the weak equivalent widths for CaIIK λ3933, CN λ4200, G-band λ4300 and MgIb λ5173, and c) the suggested UV stellar wind resonance lines (N V λ1240, Si IV λ1400 and C IV λ1550) in the IUE spectrum. Using the simple stellar population synthesis model, we find that in the nuclear 2" × 2" region, the contributions from the old, intermediate and young components are 21.7%, 42.9% and 35.4%, respectively. These nuclear starburst activities might have been triggered by the close encounter with NGC 7682, as suggested by recent numerical simulations.

We report the discovery of two new Wolf-Rayet (WR) galaxies: Mrk 1039, and F08208+2816.Two broad WR bumps at 5808Å and 4650Å indicate the presence of WCE and WNL star population in all two sources. We also confirm the presence of WR features in Mrk 35, previously detected in a different position. The observed equivalent width of the WR bump at 4650Å and the derived number ratios of WR/(WR+O) imply that star formation in these sources takes place in short burst duration. Comparisons with the recent models of WR populations in young starbursts with the observed EW(He ii λ4686)/EW(C iv λ5808)/EW(WRbump) and their relative intensities provide an indication that the stellar initial mass function in some WR galaxies might not be Salpeter-like. It is interesting to find that the luminous IRAS source, F08208+2816, has little dust reddening, probably because of the existence of a powerful superwind. By comparisons with other starbursts observed with the Hopkins Ultraviolet Telescope, F08208+2816 as a merging system renders a chance to study the contribution from young starbursts to the UV background radiation in universe.

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