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The Arizona-New Mexico Spectroscopic Survey of Galaxies. I. Data for the Western End of the Perseus Supercluster
We present new optical spectroscopic data for 347 galaxies in the regionof the Perseus supercluster. The new data were obtained using theSteward Observatory 2.3 m telescope and cover the whole optical window.Included are redshifts (for 345 objects), absorption-line equivalentwidths, a continuum index measuring the 4000 Å break, andemission-line flux ratios. After 11 objects are rejected for being toofaint and redshifts for 26 objects are added from the literature, wearrive at a complete sample of 361 galaxies. The distribution ofredshifts for the whole sample is examined, and we show the relationshipof the continuum index to morphology.
| 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.
| A survey of the Pisces-Perseus supercluster. V - The declination strip +33.5 deg to +39.5 deg and the main supercluster ridge
Measurements of 544 radial velocities, 229 optical and 315 in the 21 cmH I line, are presented for galaxies, mostly in the declination stripbetween +33.5 and +39.5 deg in the region of the Pisces-Perseussupercluster. These are combined with other available data toinvestigate the linear structure identified as the main superclusterridge. The main ridge of the supercluster extends at least 50/h Mpcbefore it disappears into the zone of avoidance east of Perseus.Confinement both on the plane of the sky and in the velocity dimensionimply an axial ratio of greater than 10:1 and an inclination withrespect to the plane of the sky of less than about 12 degrees. Therelative proximity, low inclination to the plane of the sky, and highcontrast relative to the foreground and background, help to make thePisces-Perseus filament one of the most prominent features in theextragalactic sky on large scales.
| Age determination of the open cluster NGC 2287 (M41)
Two different methods which take into account the rotation of the memberstars are used to determine the cluster age of NGC 2287 (M41). Thetheoretical Hertzsprung-Russell diagram is first obtained from theobserved color-magnitude diagram. The method based on the turn-off pointon the cluster Main Sequence yields an age of 3.10 x 10 to the 7th yr.By fitting the evolutionary tracks of rotating stars to the clusterHertzsprung-Russell diagram, an age of about 8.00 x 10 to the 7th yr isobtained.
| Correlations between integrated parameters and H-alpha velocity widths in giant extragalactic H II regions - A new appraisal
Investigations of relationships between diameters (or luminosities) andvelocity widths of H-alpha line profiles in giant extragalactic H IIregions (GEHR) have firmly established that these parameters arecorrelated. However, three independent studies on the subject disagreeon the slopes of these relations. It is shown that all measurements ofthe velocity width of integrated H-alpha profiles of GEHRs are entirelyconsistent. Discrepancies in the relations are explained by differentsamples and by the use of different parameters such as distances togalaxies and diameters of GEHRs. Assembling all observations of H-alphavelocity widths, new values of slopes and zero-points are derived forthe relations between luminosities (or diameters) and velocity widths.
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