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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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| Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
| Probing the Dust-enshrouded Regions of the Interacting Galaxy System ARP 299:A Near-Infrared Study
We present high spectral resolution (lambda/deltalambda≅10^3)Pabeta(1.28 μm) and Brgamma(2.17 μm), 3.29 μm dust feature, andnear-infrared broadband images of the Arp 299=NGC 3690/IC 694 galaxysystem. The emission is found to be concentrated at the positions ofthree active regions, known as sources A, B, and C. From ourBrgamma/Pabeta flux ratio we find the visual extinction toward theionized gas in A, B, and C is ~6, 6, and 2 magnitudes, respectively,assuming case B recombination and a foreground screen geometry for theobscuring material. Our observations can be explained entirely by astarburst model for the Arp 299 system. The putative active galacticnucleus (AGN) in source A does not dominate the properties of thissource. We see no evidence of broad recombination lines. In addition,the ratio of the 3.29 μm dust feature to total luminosity, a tracerof starburst activity, is consistent in each source with that seen inM82 and other starburst galaxies. Also, our imaging observations revealthat the dust feature emission is concentrated in the nucleus of sourceA, contrary to the extended annular distribution of the feature emissionseen surrounding the nucleus of the more distant Seyfert galaxy NGC7469. In this galaxy, the absence of the feature emission in the nucleushas been attributed to the destruction of the dust carriers in the hardradiation field surrounding the AGN. Our observations suggest that allof the active regions in Arp 299 are characterized by starburstepisodes. The observed CO indices and Brgamma equivalent widths implythat source B is older than source A and source C is the youngeststar-forming region. Although these regions are probably complexphysical systems not necessarily characterized by a single coevalpopulation of stars, we have compared our observations with aninstantaneous starburst model with a Salpeter initial mass function.Using this simple model, we find starburst ages of ~6x10^6, 8x10^6, and4x10^6 for sources A, B, and C, respectively.
| CCD astrometry and instrumental {DELTA}V photometry of wide visual double stars. IV. Differential measurements of northern pairs.
We present relative positions and instrumental visual magnitudedifferences ({DELTA}V) of 101 northern wide double star components. Themean accuracy of the magnitude differences is 0.01 magnitudes, of theangular separation 0.04 arcseconds, and of position angle 0.13 degrees.Most of the programme pairs are targets of the HIPPARCOS mission andthey have been often observed during the last 150 years.
| A preliminary compilation of DS-programme star positions
A catalog is presented of the double-star-program (DS-program) starpositions, listing right ascensions for 930 DSs and declinations for1225 DSs of the program. The positions were compiled from the observedvalues obtained between 1980 and 1987 with the meridian circles of sixUSSR observatories (the Moscow, Kazan', Kiev, Khar'kov, Odessa, andTashkent Observatories) and the Belgrade Observatory. The measurementsand the treatment of the observational material were performed using therelative method, and the FK-4 system stars were used as reference stars.
| Colors, luminosities, and motions of the nearer G-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964AJ.....69..570E&db_key=AST
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| Takýmyýldýz: | Zincirli Prenses |
| Sað Açýklýk: | 01h18m01.43s |
| Yükselim: | +53°55'00.6" |
| Görünürdeki Parlaklýk: | 8.192 |
| Uzaklýk: | 252.525 parsek |
| özdevim Sað Açýklýk: | 24.7 |
| özdevim Yükselim: | -12.1 |
| B-T magnitude: | 8.512 |
| V-T magnitude: | 8.219 |
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