A. Omizzolo, G. Fasano, D. Reverte Paya, C. De Santis, A. Grado, D. Bettoni, B. Poggianti, M. D'Onofrio, A. Moretti, J. Varela, J. Fritz, M. Gullieuszik, A. Cav… 展开作者
A. Omizzolo, G. Fasano, D. Reverte Paya, C. De Santis, A. Grado, D. Bettoni, B. Poggianti, M. D'Onofrio, A. Moretti, J. Varela, J. Fritz, M. Gullieuszik, A. Cava, A. Grazian, M. Moles
备注:
9 pages, 6 figures, accepted for publication in A&A
本文是介绍宽场近星系团巡天(WINGS)的系列文章之一。WINGS项目收集了76个X射线选定的邻近星系团(0.04 < z < 0.07)样本中星系的宽场、光学(B、V)和近红外(J、K)成像以及中等分辨率光谱,目的是为星系和星系团的演化研究建立参考样本。本文给出了WINGS样本中17个星系团的U波段测光结果。我们还扩展到一个更大的视野,原来的B-和V-波段测光(WINGS-OPT)9和6 WINGS集群,分别。我们使用新的和已经存在的B波段测光得到可靠的(U-B)颜色的星系在三个固定的孔径在千秒差距。为了达到这个目的,在还原过程中,我们特别注意天体测量的精度。由于并非所有的观测都是在良好的透明度条件下进行的,因此部分测光校准是分别依靠SDSS和WINGS-OPT测光获得的。我们提供了U波段(也B和V波段,在可能的情况下)的恒星和星系的星系团领域的总星等。仅对于星系,星表也提供了几何参数和仔细居中的孔径星等。对不同相机拍摄的星系团进行了内部星等一致性检查,并与WINGS-OPT和SDSS调查进行了比较,获得了外部光度一致性。这里提出的光度计目录添加的U-波段信息的WINGS数据库扩展的SED的星系,特别是在紫外波长的基础上推导的SFR属性。
英文摘要:
This paper belongs to a series presenting the WIde Field Nearby Galaxy-cluster Survey (WINGS). The WINGS project has collected wide-field, optical (B,V) and near-infrared (J,K) imaging, as well as medium resolution spectroscopy of galaxies in a sample of 76 X-ray selected nearby clusters (0.04 < z < 0.07), with the aim of establishing a reference sample for evolutionary studies of galaxies and galaxy clusters. In this paper we present the U-band photometry of galaxies and stars in the fields of 17 clusters of the WINGS sample. We also extend to a larger field of view the original B- and V-band photometry (WINGS-OPT) for 9 and 6 WINGS clusters, respectively. We use both the new and the already existing B-band photometry to get reliable (U-B) colors of galaxies within three fixed apertures in kpc. To this aim, in the reduction procedure we put particular care in the astrometric precision. Since not all the observations have been taken in good transparency conditions, the photometric calibration was partly obtained relying on the SDSS and WINGS-OPT photometry for the U- and optical bands, respectively. We provide U-band (also B- and V-band, where possible) total magnitudes of stars and galaxies in the fields of clusters. Just for galaxies, the catalogs also provide geometrical parameters and carefully centered aperture magnitudes. The internal consistency of magnitudes has been checked for clusters imaged with different cameras, while the external photometric consistency has been obtained comparing with the WINGS-OPT and SDSS surveys. The photometric catalogs presented here add the U-band information to the WINGS database for extending the SED of the galaxies, in particular in the UV wavelengths which are fundamental for deriving the SFR properties.
我们提出了WINGS巡天(Fasano et al. 2006)中邻近星系团的星系形态目录。该目录包含了39923个星系的总数,我们提供了自动估计的形态类型应用专门设计的工具MORPHOT的V波段WINGS成像。对于约3000个星系,我们还提供了形态类型的视觉估计。本文的一个重要部分是专门描述的MORPHOT工具,其应用是有限的,至少在目前,WINGS成像。该工具实现形态分类自动化的方法是一种非参数的、完全经验的方法。特别是,MORPHOT利用21形态诊断,直接和容易计算的星系图像,提供两个独立的分类:一个基于极大似然(ML),半分析技术,另一个神经网络(NN)机。一个适当选择的样本约1000视觉分类的WINGS星系用于校准ML估计的诊断,并作为NN机的训练集。最后的形态估计结合了这两种技术,并证明是有效的,当应用到一个额外的测试样本~1000视觉分类的WINGS星系,并与小样本的SDSS星系视觉分类的Fukugita等人(2007)和Nair等人(2010)。最后,除了WINGS星系团中的星系形态分布(校正了场污染),我们还给出了不同形态类型的椭圆率(ε),颜色(B-V)和Sersic指数(n)分布,以及形态分数作为星系团中心距离(单位为R200)的函数。