塞弗特星系NGC 5953的形态和表面色指数

用国家天文台昆明站1m光学望远镜和兴隆站2．16m光学望远镜对塞弗特2型活动星系NGC5953进行了B、V、R三色测光观测，着重研究了星系形态、三个光学波段上的表面亮度轮廓和（B-V）、（B—R）表面色指数分布。结果发现，在NGC5953星系核的附近偏北方有一个大小约2kpc、平均光谱型相当于A5的蟹状“蓝区”，该“蓝区”伸展出5条旋臂状结构并分别与5组巨电离氢区成协；在NGC5953与邻近的旋涡星系NGC5954的连接区域存在一个较弱的结构，可能是一个大小约1kpc、绝对星等约-12．75的矮星系；NGC5953表面色指数分布重心相对于巨电离氢区分布重心及星系核存在着约0．5kpc的偏离，这表明了NGC5953／4的相互作用与NGC5953中发生的恒星形成有密切相关。

Seyfert Galaxy NGC 5953: Morphology and Surface Color Indices

We measured active galaxy NGC 5953 of Seyfert 2 type at B,V,R bands respectively,with 1-m optical telescope at Kunming station and 2.16-m optical telescope at Xinglong station of the National Astronomical Observatories,Chinese Academy of Sciences,and researched the morphology of the galaxy;surface brightness at B,V,R bands,and distributions of surface-color indices(B-V)and(B-R).Our main results are listed as follows,there is a blue crab-like region with magnitude of 2 kpc and mean spectral type A5,surrounding the nucleus of NGC 5953,which extends five arm-like structures associated with five groups of super-giant HII regions respectively,there is a weak structure in the connecting region of NGC 5953 and an adjacent spiral galaxy NGC 5954,which is probably a dwarf galaxy of d=1 kpc,MV=-12.75,and there is about 0.5 kpc deviation of the distributional centroid of color indices relative to that of super-giant HII regions as well as the nucleus of NGC 5953,which reveals that the interaction between NGC 5953/4 is closely correlated to the star formation happened in NGC 5953.