SDSS观测的Virgo dEs星系的颜色
天体物理学
2009-11-11 v3
摘要
我们对SDSS中精选的200多颗Virgo星团dEs星系和8颗巨型椭圆星系(Es)进行了颜色分析，得到以下结果：a)核化dEs(dENs)遵循紧密的颜色-光度关系(CMR)，且在较暗Mr>-15的星系中未出现显著展宽；b)dENs的CMR与Es的CMR平滑过渡，但后者在约Mr=-20处改变斜率；c)较亮的dENs与t>5Gyr的年龄相符，且金属丰度随星系变暗而减小，但可能存在额外的光度-年龄关系尚未被排除；d)必须将dS0星系与dEs星系分开处理，因为二者的不同颜色特性否则会偏向核化与非核化dEs(dEnoNs)的比较；e)dEnoNs显示出比dENs更蓝的颜色趋势。
引用
@article{arxiv.astro-ph/0505048,
title = {The colours of Virgo dEs as seen by SDSS},
author = {Thorsten Lisker and Eva K. Grebel and Bruno Binggeli},
journal= {arXiv preprint arXiv:astro-ph/0505048},
year = {2009}
}
备注
3 pages + 3 figures; to appear in the proceedings of the IAUC198 "Near-Field Cosmology with Dwarf Elliptical Galaxies", H. Jerjen & B. Binggeli (eds.); replaced with revised version after finding that the SDSS photometric pipeline overestimated the sky flux - the conclusions remain unchanged though; feel free to contact the authors for further details; additional minor correction in Fig. 3