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Chromospheric Ca II Emission in Nearby F, G, K, and M Stars
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We have undertaken a search for SAO stars with infrared excess in theIRAS Point Source Catalog. In contrast to previous searches, the entireIRAS (12)-(25)-(60) color-color diagram was used. This selection yieldeda sample of 462 stars, of which a significant number are stars withcircumstellar material. The stars selected can be identified aspre-main-sequence stars, Be stars, protoplanetary systems, post-AGBstars, etc. A number of objects are (visual) binary stars.Characteristic temperatures and IR excesses are calculated and theirrelations to spectral type are investigated.
| UBV photometry of stars whose positions are accurately known. III
UBV photometric observations of 417 stars at BD declination 35-49 degfrom the NPZT(74) catalog of Yasuda et al. (1982) and the AGK3R catalogof Corben (1978), obtained with the 40-cm Cassegrain reflector atKvistaberg Observatory during 1984-1985, are reported. The data arepresented in tables, and the mean errors per observation are given as0.016 mag in V, 0.011 mag in B-V, 0.012 mag in U-B for U less than 10,and 0.026 mag in U-B for U greater than 10.
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Ursa Major |
| Ascensió Recta: | 10h18m32.82s |
| Declinació: | +43°02'54.4" |
| Magnitud Aparent: | 6.496 |
| Distancia: | 35.613 parsecs |
| Moviment propi RA: | -124.2 |
| Moviment propi Dec: | -78.1 |
| B-T magnitude: | 7.646 |
| V-T magnitude: | 6.591 |
Catàlegs i designacions:
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INHABITED SKY
