The evolution of dwarf galaxies: a comparison of UBVR photometry
The evolution of dwarf galaxies: a comparison of UBVR photometry
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DOI：
10.1111/j.1365-2966.2010.17117.x
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发表时间：
2010-10
影响因子：
4.8
通讯作者：
J. Dunn
中科院分区：
文献类型：
--
作者：
J. Dunn
利用29个矮星系的宽波段UBVR测光研究了矮不规则星系和矮椭圆/椭球星系之间的演化联系。这些星系的绝对B波段星等范围从-13.67到-19.86等，距离范围从7到108 Mpc。宽带颜色和Sersic表面亮度轮廓拟合进行了比较的两种形态类型。两个子样本之间的所有光学参数均存在统计学差异，如Kolmogorov-Smirnov统计量的显著性水平所示。其他人则指出，矮椭圆星系可能看起来很像过去根据光学颜色观察到的矮不规则星系。两个样本的n值（从Sersic轮廓拟合确定的幂律指数）存在差异，这表明两种主要类型的矮星系在结构上是不同的。恒星成分结构的差异意味着矮不规则星系不会孤立地演化成矮椭圆星系，这意味着如果要发生转变，就需要某种外部相互作用。星系的环境最初被分类为场或群/星系团（尽管这里没有明确的环境比较）。
The proposed evolutionary link between dwarf irregular and dwarf elliptical/spheroidal galaxies is investigated using broad-band UBVR photometry obtained for a sample of 29 dwarf galaxies. The galaxies span a range of absolute B-band magnitude from -13.67 to -19.86 mag, and range in distance from about 7 to 108 Mpc. Broad-band colours and Sersic surface brightness profile fits are compared for the two morphological types. All optical parameters are statistically different between the two subsamples, as evidenced by the significance level of the Kolmogorov―Smirnov statistic. Others have noted that dwarf ellipticals might have looked much like the currently observed dwarf irregulars in the past based on optical colours. A difference is noted between the two samples in the value of n (the power-law exponent determined from the Sersic profile fitting), suggesting that the two main types of dwarf galaxy are structurally distinct. The differences in the structure of the stellar components imply that dwarf irregulars do not evolve to become dwarf ellipticals in isolation, meaning that some sort of external interaction is required if the transformation is to occur. The environments of the galaxies are initially classified as either field or group/cluster (though no definitive environmental comparison is presented here).