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Flare Activity and an Optical Superflare of the X-ray Object 1RXS J220111+281849
A UBVR monitoring of the X-ray source 1RXS J220111+281849 was performedduring August 2-21, 1999. Seven moderately intense ultraviolet flareswith 1-3 mag amplitudes were detected. The object exhibits both rapidand slow flares. An unusual superintense flare with an 11.0 magamplitude in U was detected on August 18, 1999. Light curves of theflares are presented, and their physical parameters are brieflyanalyzed.
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We publish 734 radial velocities of stars distributed in 28 fields of4x4deg. We continue the PPO series (Fehrenbach et al. 1987; Duflot etal. 1990 and 1992), using the Fehrenbach objective prism method.
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Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979AJ.....84..783D&db_key=AST
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Datos observacionales y astrométricos
| Constelación: | Acuario |
| Ascensión Recta: | 22h42m23.81s |
| Declinación: | +00°46'13.7" |
| Magnitud Aparente: | 8.525 |
| Distancia: | 362.319 parsecs |
| Movimiento Propio en Ascensión Recta: | 16.3 |
| Movimiento Propio en Declinación: | -16.3 |
| B-T magnitude: | 9.802 |
| V-T magnitude: | 8.631 |
Catálogos y designaciones:
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