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Kinematics of the local universe . XII. 21-cm line measurements of 586 galaxies with the new Nançay receiver
This paper presents 586 new 21-cm neutral hydrogen line measurementscarried out with the FORT receiver of the meridian transit Nançayradiotelescope in the period July 2000-March 2003. This observationalprogramme is part of a larger project aiming at collecting an exhaustiveand magnitude-complete HI extragalactic catalogue for Tully-Fisherapplications. It is associated with the building of the MIGALEspectroscopic archive and database.Tables 2, 3 and HI-profiles and corresponding comments are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/430/373, or directly atour web site http://klun.obs-nancay.fr
| Galaxy Luminosity Functions from Deep Spectroscopic Samples of Rich Clusters
Using a new spectroscopic sample and methods accounting forspectroscopic sampling fractions that vary in magnitude and surfacebrightness, we present R-band galaxy luminosity functions (GLFs) for sixnearby galaxy clusters with redshifts of 4000 kms-1
| Pre-Main-Sequence Stars in the Young Galactic Cluster IC 4996: A CCD Photometric Study
The results of a UBV CCD photometric study of the cluster IC 4996 arepresented. We obtain new values for the cluster parameters: E(B-V) =0.71 +/- 0.08, V_0 - M_V = 11.9 +/- 0.1, and age = (7.5 +/- 3) x 10^6yr. The combined evidence from the photometric diagrams suggests thepresence of a number of pre-main-sequence (PMS) cluster members withspectral types ~A0 to F5. The interpretation of these objects as PMScandidates is further supported by independent results from CCD uvbyHβ observations. If confirmed, these stars would bridge theexisting gap in the sample of PMS stars, between the coolest Herbig AeBestars (HAeBe), and the hottest T Tauri stars. These PMS candidates arelocated some 0.5 and 1 mag above the main sequence in the V-(B-V)diagram, around the location of spectral types AF. This feature,together with their locations in the (U-B)-(B-V) diagram and theinterpretation that they are PMS members, suggest an additionalreddening law with a slope alpha = E(U-B)/E(B-V) ~= 0.55, probablycaused by circumstellar material.
| 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.
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