WINGS: A WIde-field Nearby Galaxy-cluster Survey - II. Deep optical photometry of 77 nearby clusters
WINGS: A WIde-field Nearby Galaxy-cluster Survey - II. Deep optical photometry of 77 nearby clusters
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WINGS：大范围邻近星系团巡天 - II。
DOI：
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发表时间：
2009
期刊：
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通讯作者：
T. Valentinuzzi
中科院分区：
文献类型：
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作者：
J. Varela;M. D’Onofrio;C. Marmo;G. Fasano;D. Bettoni;A. Cava;W. Couch;A. Dressler;P. Kjaergaard;M. Molés;E. Pignatelli;B. Poggianti;T. Valentinuzzi
背景：这是致力于广域近星系团巡天（WINGS）系列的第二篇论文。WINGS是一个长期的项目，它收集了77个X射线选择的完整样本中星系的宽场，多波段成像和光谱学，位于远离银道面的附近星系团（0.04 < z < 0.07）（|B| ≥ 20°）。该项目的主要目标是为星系和星系团的演化研究建立一个本地参考。目的：本文介绍了WINGS样本的光学（B，V）光度星表，并描述了随后的程序来构建它们。我们特别注意正确对待大的扩展星系（包括最亮的星系团）和减少非常亮的恒星的明亮晕的影响。方法：我们使用SExtractor构建了基于B和V波段宽视场图像的光度星表。在用椭圆等照度线模拟大星系和亮星晕后，将其去除的图像上进行了测光。结果如下：我们公布了深光学测光星表（在V ~ 21.7处完成了90%，在平均红移处转换为10 M^*_V+6），给出了所有探测到的天体的位置、几何参数和几个总星等和孔径星等。对于每个领域，我们已经产生了三个目录，包含星系，恒星和“未知”分类的对象（~6%）。从模拟中，我们发现我们的光度测量的不确定性很大程度上取决于天体的光分布，其中恒星具有最稳健的光度测量，de Vaucouleurs轮廓显示出更高的不确定性，并且还有~-0.2^m的额外偏差。目视检查明亮天体（V < 20）的星星/星系分类，使错误分类天体的比例可以忽略不计。对于较暗的对象，我们发现，模拟不提供可靠的估计可能的错误分类，因此，我们比较了我们的数据与深计数的星系和星星计数从我们的银河系模型。这两组结果是一致的，我们的数据在~5%（星系/总的比率）到V ~ 24。最后，我们注意到，我们的特殊程序，以消除大晕的应用程序，提高了我们的样本中的大星系的光度测定相对于使用盲目的自动程序，并增加（~16%）的物体投射到他们的检测率。根据设在Roque de los Muchachos（西班牙拉帕尔马）的Issac Newton望远镜（2.5 m-INT）和设在La Silla（智利）的MPG/ESO-2.2 m望远镜的观测结果。附录仅以电子形式在http://www.aanda.org上提供，目录仅以电子形式在CDS上通过匿名FTP到cdsarc.u-strasbg.fr（130.79.128.5）或通过http://cdsweb.u-strasbg.fr/cgi-bin/qcat?提供J/A+A/497/667
Context: This is the second paper of a series devoted to the WIde Field Nearby Galaxy-cluster Survey (WINGS). WINGS is a long term project which is gathering wide-field, multi-band imaging and spectroscopy of galaxies in a complete sample of 77 X-ray selected, nearby clusters (0.04 < z < 0.07) located far from the galactic plane (|b|≥ 20°). The main goal of this project is to establish a local reference for evolutionary studies of galaxies and galaxy clusters. Aims: This paper presents the optical (B,V) photometric catalogs of the WINGS sample and describes the procedures followed to construct them. We have paid special care to correctly treat the large extended galaxies (which includes the brightest cluster galaxies) and the reduction of the influence of the bright halos of very bright stars. Methods: We have constructed photometric catalogs based on wide-field images in B and V bands using SExtractor. Photometry has been performed on images in which large galaxies and halos of bright stars were removed after modeling them with elliptical isophotes. Results: We publish deep optical photometric catalogs (90% complete at V ~ 21.7, which translates to ˜ M^*_V+6 at mean redshift), giving positions, geometrical parameters, and several total and aperture magnitudes for all the objects detected. For each field we have produced three catalogs containing galaxies, stars and objects of "unknown" classification (~6%). From simulations we found that the uncertainty of our photometry is quite dependent of the light profile of the objects with stars having the most robust photometry and de Vaucouleurs profiles showing higher uncertainties and also an additional bias of ~-0.2^m. The star/galaxy classification of the bright objects (V < 20) was checked visually making negligible the fraction of misclassified objects. For fainter objects, we found that simulations do not provide reliable estimates of the possible misclassification and therefore we have compared our data with that from deep counts of galaxies and star counts from models of our Galaxy. Both sets turned out to be consistent with our data within ~5% (in the ratio galaxies/total) up to V ~ 24. Finally, we remark that the application of our special procedure to remove large halos improves the photometry of the large galaxies in our sample with respect to the use of blind automatic procedures and increases (~16%) the detection rate of objects projected onto them. Based on observations taken at the Issac Newton Telescope (2.5 m-INT) sited at Roque de los Muchachos (La Palma, Spain), and the MPG/ESO-2.2 m Telescope sited at La Silla (Chile). Appendices are only available in electronic form at http://www.aanda.org Catalog is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/497/667