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IC 4546


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Spectroscopy of KISS Emission-Line Galaxy Candidates. I. MDM Observations
Spectroscopic observations for 351 emission-line galaxy candidates fromthe KPNO International Spectroscopic Survey (KISS) have been obtainedusing the MDM Observatory 2.4 m telescope on Kitt Peak. KISS is anongoing wide-field objective-prism survey for extragalacticemission-line objects, which has cataloged over 2200 emission-linegalaxy (ELG) candidates to date. Spectroscopic follow-up observationsare being carried out to study the characteristics of the surveyobjects. The observational data presented here include redshifts,reddening estimates, line equivalent widths, Hα line fluxes, andemission-line ratios. The galaxies have been classified based on theiremission-line characteristics. The procedure for selecting the ELGcandidates in KISS is found to be very reliable: 95% of the candidatesin this sample are verified to have emission lines. A comparison ofobjective-prism survey data-redshifts, Hα line fluxes, andequivalent widths-with the long-slit measurements shows good overallagreement.

Redshifts for 2410 Galaxies in the Century Survey Region
The Century Survey strip covers 102 deg2 within the limits8h5<=α<=16h5, 29.0d<=δ<=30.0d, equinoxB1950.0. The strip passes through the Corona Borealis supercluster andthe outer region of the Coma cluster. Within the Century Survey region,we have measured 2410 redshifts that constitute four overlappingcomplete redshift surveys: (1) 1728 galaxies with Kron-CousinsRph<=16.13 covering the entire strip, (2) 507 galaxieswith Rph<=16.4 in right ascension range8h32m<=α<=10h45m, equinox B1950.0, (3) 1251 galaxies withabsorption- and K-corrected RCCDc<=16.2 (where ``c''indicates ``corrected'') covering the right ascension range8h5<=α<=13h5, equinox B1950.0, and (4) 1255 galaxieswith absorption- and K-corrected VCCDc<=16.7 also coveringthe right ascension range 8h5<=α<=13h5, equinoxB1950.0. All these redshift samples are more than 98% complete to thespecified magnitude limit. We derived samples 1 and 2 from scans of thePOSS1 red (E) plates calibrated with CCD photometry. We derived samples3 and 4 from deep V and R CCD images covering the entire region. Weinclude coarse morphological types for all the galaxies in sample 1. Thedistribution of (V-R)CCD for each type correspondsappropriately with the classification. Work reported here is basedpartly on observations obtained at the Michigan-Dartmouth-MITObservatory.

The KPNO International Spectroscopic Survey. II. Hα-selected Survey List 1
The KPNO International Spectroscopic Survey (KISS) is a newobjective-prism survey for extragalactic emission-line objects. Itcombines many of the features of previous slitless spectroscopic surveyswith the advantages of modern CCD detectors and is the first purelydigital objective-prism survey for emission-line galaxies. Here wepresent the first list of emission-line galaxy candidates selected fromour red spectral data, which cover the spectral range 6400 to 7200Å. In most cases, the detected emission line is Hα. Thecurrent survey list covers a 1°-wide strip located atδ=29°30' (B1950.0) and spanning the right ascension range12h15m to 17h0m. An area of62.2 deg2 is covered. A total of 1128 candidate emission-lineobjects have been selected for inclusion in the survey list (18.1deg-2). We tabulate accurate coordinates and photometry foreach source, as well as estimates of the redshift and emission-line fluxand equivalent width based on measurements of the digitalobjective-prism spectra. The properties of the KISS emission-linegalaxies are examined using the available observational data.

Dynamics of cD Clusters of Galaxies. III. Redshift Data for 11 Abell Clusters
We present the final observational data for a spectroscopic study of asample of cD galaxy clusters. The goal of this program has been to studythe dynamics of the clusters, with emphasis on determining the natureand frequency of peculiar-velocity cD galaxies. In this paper we presentredshifts for 762 galaxies in the fields of the rich Abell clustersA779, A1691, A1749, A1767, A1837, A1927, A2067, A2079, A2089, A2199, andA2666. We also present preliminary dynamical properties for theseclusters using our measured redshifts.

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.

Galaxy structures in the Hercules region
216 redshifts have been obtained in a region of 981 sq deg south of theHercules supercluster. 172 of these redshifts are of galaxies withmpg less than or equal to 15.1, 110 of which had no previousvelocity measurement. 44 new redshifts are of galaxies fainter thanmpg = 15.1. With these new data we have been able to define asample in a vast region (approximately 1700 sq deg) around Herculeslimited to mpg less than or equal to 15.1 with a velocitycompleteness of 81.5%. 189 galaxies have been morphologically classifiedso that all galaxies in the sample with known velocity now also haveknown morphology. The magnitude limited sample, including 556 galaxies,is then used to identify and describe galaxy structures in the region.We find that the overdense volume is small, that its overall appearanceis that of a coral branch floating in a sea of nothing and that earlyand late type galaxies defined different structures.

H I observations of galaxies in the Hercules supercluster. II - Additional UGC galaxies and galaxies in selected CGCG fields
The second installment of a H I redshift survey in the region of theHercules supercluster is presented. This part of the survey presents 218H I spectra of galaxies selected from the UGC which extends thepreviously begun survey of UGC galaxies in that region. In addition,spectra of 136 galaxies from selected CGCG fields are given. The CGCGfields were chosen to cover the projected position of the Hercules void.Measured H I parameters from the spectra are given. This survey wasconducted for application of the Tully-Fisher relation to search forstreaming motion around the void in front of the supercluster. Theselection effects affecting such a search are discussed in detail.

Tests for alignment of galaxy position angles within a sheet of galaxies
Measured position angles of 149 galaxies that lie in a sheet near thevoid in Corona Borealis are presented. The distribution of positions andposition angles is tested for alignment; none is detected.

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.

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Datos observacionales y astrométricos

Constelación:Corona Boreal
Ascensión Recta:15h26m58.40s
Declinación:+28°51'09.0"
Dimensión Aparente:0.692′ × 0.589′

Catálogos y designaciones:
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ICIC 4546
HYPERLEDA-IPGC 55115

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