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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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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.
| Systematic search for UV-excess quasar candidates in 40 square degrees at the North Galactic Pole.
We have developed a procedure (so called PAPA) for measurement ofmagnitudes (about 0.1mag accurate) and positions (with accuracy betterthan 0.5arcsec) of all the objects present on photographic platesdigitised with the MAMA machine. This homogeneous procedure was appliedto four Schmidt plates - in U, B and twice V - covering thePalomar-Sky-Survey field PS +30deg 13h00m, a 40-square-degree zone atthe North Galactic Pole. A general-interest exhaustive tricolourcatalogue of 19542 star-like objects down to V=20.0 has been producedand we selected 1681 quasar candidates on the basis of ultravioletexcess and, when possible, absence of any measurable proper motion. Theastrometric and photometric catalogue of the candidates is given inelectronic form. A first multi-object spectroscopy of a few candidatesconfirms validity of the selection.
| 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.
| 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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| 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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