本論文主要探討西佛星系的性質與其宿主星系形態間的關係。我從Véron第十三版目錄中挑選出紅移小於0.5的西佛星系，並且使用SDSS星系擬合所得到的參數，FracDev，來代表星系凸核(bulge)占整個星系的比例。我們發現西佛一型與西佛二型星系大部分都具有很大的凸核，而西佛二型星系又比西佛一型星系較常出現在盤狀星系。這些結果顯示活躍星系核的種類與其宿主星系有關，而傳統的統一模型沒有辦法解釋這個結果。此外，我們也發現西佛星系的平均發射線的強度跟凸核的大小有關。而且，在西佛二型星系內，有較強吸積率的星系核的宿主星系擁有比較年輕的恆星族群，這個結果顯示活躍星系核的活躍度可能與其宿主星系有關，這些結果都無法用傳統的活躍星系核統一模型解釋。;We probed the relation between properties of Seyfert nuclei and morphology of their host galaxies. We selected Seyfert galaxies from the Véron Catalog (13th). We only selected the Seyfert galaxies with redshifts less 0.5. We used the "FracDev" parameter from SDSS galaxy fitting models to represent the bulge fractions of the Seyfert host galaxies. We found that the host galaxies of Seyfert 1 and Seyfert 2 are dominated by large bulge fractions, and Seyfert 2 galaxies are more likely to be located in disk galaxies whereas most of the Seyfert 1 galaxies are located in bulge-dominant galaxies. These results indicate that the types of AGNs are related to their host galaxies and can not be explained by the traditional unification model of Seyfert galaxies. Besides, we found that the mean luminosities of emission lines of Seyfert 1 and Seyfert 2 correlate with "FracDev". We found that Seyfert 2 galaxies with stronger accretion rates have younger stellar populations than Seyfert 2 galaxies with weaker ones. This result suggests that AGN activities might be related to their host galaxies.
