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Fe/H, age and distance for the F-stars of an unbiased radial velocity sample at the north Galactic pole New limits for the normalization of stellar populations of the solarneighborhood have been suggested by Sandage and Fouts (1987). Log T(e),M(V), Fe/H abundance ratio, age A, distance and color excess arepresented for 183 stars of Sandage and Fouts' unbiased radial velocitysample located near the north Galactic pole.
| 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.
| U, V, W velocity components for the old disk using radial velocities of 1295 stars in the three cardinal Galactic directions New radial velocities are presented for 1295 stars chosen at random nearthe three cardinal Galactic directions of l = 180 deg, b = 0; l = 90deg, b = 0 deg; and b = 90 deg, giving the distribution in U, V, and W,respectively, from the radial velocities alone. The measurements weremade with the coude spectrograph of the Mount Wilson 100 in. Hookerreflector. The purpose of the program is to set limits on the densitynormalization in the solar neighborhood of the old thin disk, the oldthick disk, and the halo. Many more high-velocity stars are present inthe unbiased sample than expected from previous estimates of thenormalization. The data suggest the density ratios in the solarneighborhood to be about 90 percent, 10 percent, and about 0.5 percentfor the thin disk, thick disk, and halo populations, respectively.
| 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 Not Available
| 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 Not Available
| Studies of A and F stars in the region of the North galactic pole-II. uvby β photometry Not Available
| Studies of A and F stars in the region of the North galactic pole-I. Radial velocities and MK Classifications Not Available
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Besorolás csoportokba:
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Pozíciós és asztrometriai adatok
Csillagkép: | Bereniké Haja |
Rektaszcenzió: | 13h05m03.52s |
Deklináció: | +21°29'38.2" |
Vizuális fényesség: | 8.713 |
Távolság: | 213.22 parszek |
RA sajátmozgás: | -49.3 |
Dec sajátmozgás: | 7.1 |
B-T magnitude: | 9.418 |
V-T magnitude: | 8.772 |
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