Seyfert 2 Galaxies with Spectropolarimetric Observations
  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. 
Qiusheng Gu Jiehao Huang