目录
图像
上传图像
DSS Images Other Images
相关文章
Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
| 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.
| The CfA Redshift Survey: Data for the NGP +36 Zone
We have assembled redshifts for a complete sample of 719 galaxies withm_zw_ <= 15.5 in the declination range 32.5^deg^ <= δ <=38.5^deg^ and right ascension range 8^h^ <= α <= 17^h^. Wehave determined morphological types for all galaxies in the magnitudelimited sample by direct inspection of the POSS-O plates. 576 of theredshifts are measurements from Mount Hopkins, and 405 are newredshifts. We also include new redshifts for 77 fainter galaxies in thesame strip.
| Groups of galaxies in the Center for Astrophysics redshift survey
By applying the Huchra and Geller (1982) objective group identificationalgorithm to the Center for Astrophysics' redshift survey, a catalog of128 groups with three or more members is extracted, and 92 of these areused as a statistical sample. A comparison of the distribution of groupcenters with the distribution of all galaxies in the survey indicatesqualitatively that groups trace the large-scale structure of the region.The physical properties of groups may be related to the details oflarge-scale structure, and it is concluded that differences among groupcatalogs may be due to the properties of large-scale structures andtheir location relative to the survey limits.
| Radio emission in isolated and cluster spiral galaxies
In the 2380-MHz continuum radio observations presented for two samplesof spiral galaxies observed with the NAIC Arecibo 305-m telescope, thesamples have been chosen in such a way that they differ markedly in thedensity of surrounding galaxies. One sample includes exclusivelygalaxies from the Karachentseva (1973) Catalog of Isolated Galaxies, theother only galaxies found within one Abell radius from the center ofnearby Abell clusters. The goal is to obtain a comparison of the radioproperties of the galaxies in these two samples, to ascertain whetherenvironmental processes affect significantly their radio emissivity.Above a threshold of five times the rms confusion, 7 percent of thecluster galaxies and 5 percent of the isolated ones are detected. Withthe caution required by the effects of confusion on the single-dishobservations, no significant differences are found in theradio-continuum properties of these two samples.
|
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:
|
