目录
图像
上传图像
DSS Images Other Images
相关文章
The UZC-SSRS2 Group Catalog
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
| An image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
| Magnesium, silicon, and iron abundances and the cluster metallicity scale
Abundances have been determined for a number of giant stars in open andglobular clusters on the basis of broadband Washington photometry, andhigh-resolution echelle spectroscopy. The photometric observations weremade with the CTIO 91-nm and 1.5 m reflectors, and the KPNO 1.3 mreflector during 44 consecutive nights between May 1980 and September1982. The spectrographic observations were carried out between 1981 andJanuary 1982, with the KNO KPNO 4-m echelle spectrograph. The spectralresolution was approximately 0.3 A and the wavelength coverage was from5500 to 7000 A. The classical metal-rich globular clusters NGC 6352,M69, and M71 are found to have Fe/H values of less than -1. Themetal-poor open clusters NGC 2141, 2158, 2506, and Melotte 66 have Fe/Hvalues ranging from -0.5 to -1.2. Mg and Si were significantly enhancedrelative to Fe in many of the clusters, and a much better correlation isfound between the color of the cluster giant branch and the mean (Mg +Si + Fe) abundance than with the Fe abundance alone. The data for thecluster abundances are presented in a table.
|
提交文章
相关链接
提交链接
下列团体成员
|
观测天体数据
目录:
|
