Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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Effective temperature scale and bolometric corrections from 2MASS photometry
We present a method to determine effective temperatures, angularsemi-diameters and bolometric corrections for population I and II FGKtype stars based on V and 2MASS IR photometry. Accurate calibration isaccomplished by using a sample of solar analogues, whose averagetemperature is assumed to be equal to the solar effective temperature of5777 K. By taking into account all possible sources of error we estimateassociated uncertainties to better than 1% in effective temperature andin the range 1.0-2.5% in angular semi-diameter for unreddened stars.Comparison of our new temperatures with other determinations extractedfrom the literature indicates, in general, remarkably good agreement.These results suggest that the effective temperaure scale of FGK starsis currently established with an accuracy better than 0.5%-1%. Theapplication of the method to a sample of 10 999 dwarfs in the Hipparcoscatalogue allows us to define temperature and bolometric correction (Kband) calibrations as a function of (V-K), [m/H] and log g. Bolometriccorrections in the V and K bands as a function of T_eff, [m/H] and log gare also given. We provide effective temperatures, angularsemi-diameters, radii and bolometric corrections in the V and K bandsfor the 10 999 FGK stars in our sample with the correspondinguncertainties.
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Limits on the short-timescale near-infrared variability of Seyfert 1 nuclei
We present new time-resolved photometric observations and images at 2.2microns of a small sample of X-ray variable Seyfert 1 nuclei. Aftercorrecting for dilution by the host galaxy in the observing aperture, wecompare the fractional variation, over the timescales of theobservations, in the near-infrared (NIR) to that expected in the X rays.We have not detected with confidence any NIR variability on timescalesshort enough to be incompatible with the dust reradiation scenario. Thegalaxy-corrected upper limits which we have obtained for variations onshort timescales, typical of non-thermal processes, imply that the NIRemission is dominated by a slowly varying, presumably reprocessed,component which accounts for no less than 80%-90% of the total.
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Photoelectric UBV photometry of northern stars from the HK objective-prism survey. II
Photoelectric UBV photometry is presented for a sample of 165 starsdrawn from the extension of the HK objective-prism/interference-filtersurvey of Beers, Preston, and Shectman to the northern galactichemisphere. These results are part of continuing follow-up observationsof candidate metal-deficient and horizontal-branch field stars and otherinteresting stars identified in the survey. A complete set ofphotometric observations is now available for three of the25-square-degree survey fields. The complete photometric sample of 299northern HK candidates obtained to date contains on order 90main-sequence turnoff, subgiant, and giant stars with (Fe/H) of lessthan or equal to -1.0, 50 field blue horizontal-branch stars, and 30stars with the photometric properties of field-blue stragglers.
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Kinematics and properties of F stars near the North Galactic Pole. II - The isothermal disc
Radial velocities are given for about 550 photometrically-identifieddisk-population F stars lying within 15 deg of the North Galactic Pole.The overall radial and z-velocity distributions are found to be closelyGaussian, with corrected rms and mean z velocities of 11.3 + or - 0.6and -9.5 + or - 0.5 km/s, respectively. The isothermal kinematics of thepopulation are reflected in the constant velocity dispersion to a zdistance of 400 pc. No systematic variation of either the velocitydispersion or the stellar age with the metallicity-sensitive Stromgrendelta m1 index is noted over a range of ages up to 5 Gyr.
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Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Four - a Catalogue of Uvbyr Photometry and Derived Quantities
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Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Three - a Catalogue of Star Names and Positions
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Space distribution of stars of intermediate spectral type in a North galactic pole region.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963AJ.....68..194U&db_key=AST
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Investigations on the stars in high galactic latitudes. III. Spectrophotometric analysis of about 3000 stars down to the photographic magnitude 13.5.
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Stars with large proper motions in the astrographic zones+ 32° and + 33° (List I)
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INHABITED SKY
