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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.
| E. W. Fick Observatory stellar radial velocity measurements. I - 1976-1984
Stellar radial velocity observations made with the large vacuumhigh-dispersion photoelectric radial velocity spectrometer at FickObservatory are reported. This includes nearly 2000 late-type starsobserved during 585 nights. Gradual modifications to this instrumentover its first eight years of operation have reduced the observationalerror for high-quality dip observations to + or - 0.8 km/s.
| Photoelectric observations of lunar occultations. XIV
Observations of 314 events between March 1982 and March 1983 arepresented in the same form as in previous papers in this series. Theresults include 18 cases of duplicity of which 12 appear to be newdiscoveries. Unluckily, few cases of possible large angular diametersoccurred, and in no case can the results derived be accepted withoutreserve, these having been observed at very low altitudes withconsequent severe corruption by seeing effects. A remark on theincidence of doubles in the Hyades and its possible consequences forestimates of stellar distances is appended.
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Taurus |
| Ascensió Recta: | 05h46m10.58s |
| Declinació: | +22°46'21.5" |
| Magnitud Aparent: | 8.194 |
| Distancia: | 280.899 parsecs |
| Moviment propi RA: | -2.8 |
| Moviment propi Dec: | -24.8 |
| B-T magnitude: | 9.751 |
| V-T magnitude: | 8.323 |
Catàlegs i designacions:
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