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Six centimetre VLA radio survey of compact planetary nebulae
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| An uvby-beta catalogue of F0-K0 supergiant stars brighter than V = 6.5
Photoelectric uvby-beta photometry is reported for 111 F0-K0 supergiantstars which are brighter than V = 6.5 mag and located betweendeclination of -15 and +61 deg. A comparison with previous observationsis made. A few stars which are suspected to present light variations arementioned.
| Spectroscopic tests of photoelectric stellar classification of abnormal stars
Spectroscopic classification is obtained for 169 northern A5-G0 starspredicted by Olsen (1979, 1980) to have abnormal spectra on the basis ofStromgren four-color photometry. The success in identifying reddenedearly type stars was nearly 100 percent, for Am and early type weaklined stars about 75 percent, for stars above main sequence about 50percent, for composite spectra about 25 percent, and for Ap and LambdaBoo stars 0 percent. Thus photoelectric photometry is a successful firststep in discovering stars of the more extreme spectroscopicabnormalities.
| Estimation of spectral classifications for bright northern stars with interesting Stromgren indices
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Aquila |
| Ascensió Recta: | 19h26m12.22s |
| Declinació: | +15°33'06.8" |
| Magnitud Aparent: | 8.253 |
| Distancia: | 421.941 parsecs |
| Moviment propi RA: | 1 |
| Moviment propi Dec: | -7.2 |
| B-T magnitude: | 8.557 |
| V-T magnitude: | 8.279 |
Catàlegs i designacions:
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