本篇論文主要是探討具有偏極化寬譜線 ( Polarized broad line ) 與不具有偏極化寬譜線的西佛二型星系 ( Seyfert 2 Galaxies )，其核心塵埃的特性。我們使用哈伯太空望遠鏡 ( Hubble Space Telescope ) 的光學影像再加上 Galfit 程式來探討這些星系在內部 1 kpc 的範圍中，其塵埃結構的不同。大部分星系的中心範圍都顯示有複雜的塵埃結構。然而，具有偏極化寬譜線的西佛二型星系與不具有偏極化寬譜線的西佛二型星系在中心塵埃結構上並沒有顯著的差異，這與之前的研究並不符合。我們也從影像上估計了這些星系中心 1 kpc 裡的塵埃質量，同時跟其他的特性相比較，包括 [OIII]，遠紅外 ( Far Infrared ) 與無線電波 ( Radio )。我們的研究發現具有偏極化寬譜線的西佛二型星系與不具有偏極化寬譜線的西佛二型星系，其能量在本質上是被不同的機制所主宰而且無法由統一模型 ( Unification Model ) 來解釋。

We investigate the nuclear dust properties of Hidden Broad Line Region (HBLR) and non-HBLR Seyfert 2 galaxies (Sy2s). Optical images obtained from the Hubble Space Telescope for a selected sample of HBLR and non-HBLR Sy2s are fitted with the GALFIT package (Peng et al. 2002) to probe the inner structures of these galaxies within the central 1 kpc regions. Most of the galaxies show complicated dust features in the
regions. However, the dust morphology shows no significant di erence between the HBLR and non-HBLR Sy2s. Dust masses inside the 1 kpc nuclear regions (M_1kpc) are estimated from the obscuration levels in the central regions of these galaxies. We compare our results with other observed properties, including [OIII], far infrared, and radio emission. We find that HBLR and non-HBLR Sy2s are dominated by di erent emission mechanisms and suggest that they are intrinsically di erent and can not be explained by the standard unification model.

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