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Uvbyβ photometry of all stars earlier than G0 and brighter than m_pg_~10.3mag in Selected Area 194 Four-colour and Hβ photometry is introduced for 594 stars earlierthan G0 in the Kapteyn's Selected Area 194. The results give V, b-y,m_1_, c_1_, and β on the standard systems, with overall rms errorsfor one observation of one star of 0.009mag, 0.004mag, 0.006mag,0.009mag, and 0.009mag, respectively. The data cover an area of about5deg x 5deg and is intended for an investigation of the distribution ofthe interstellar medium toward the northern part of the SouthernCoalsack and its surroundings. A comparison to earlier results obtainedby other authors has shown that the c_1_ indices obtained for the latetype stars were underestimated, in average, by 0.020mag. Since suchdifference may account for an error of little more than 10% in theestimated stellar distances, a correction was applied to the c_1_ indexof these stars.
| Stromgren and H-beta photometry of stars earlier than G0 in the Southern Coalsack direction Four-color and H-beta photometry have been obtained for 236 starsearlier than G0 in order to study the color excess distribution in theSouthern Coalsack direction. The beta histogram of the stars reveals arelative absence of stars in the range of A4 to A9. The (b-y)distribution for B-type stars suggests the existence of three differenttypes of stars located at different distances.
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Osservazione e dati astrometrici
Costellazione: | Croce del Sud |
Ascensione retta: | 12h44m56.46s |
Declinazione: | -62°12'51.3" |
Magnitudine apparente: | 8.859 |
Distanza: | 1666.667 parsec |
Moto proprio RA: | -27.7 |
Moto proprio Dec: | -2.6 |
B-T magnitude: | 9.942 |
V-T magnitude: | 8.949 |
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