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| Small Amplitude Red Variables in the AAVSO Photoelectric Program: Light Curves and Periods
Small-amplitude red variables (SARVs) are M giants or supergiants whichare pulsating with small amplitudes (up to 2.5 mag) and with time scalesof 20 to 200 days or more. This paper reports on a ten-year study ofabout two dozen SARVs, carried out through the American Association ofVariable Star Observers (AAVSO) photoelectric photometry program. It hasprovided detailed information on the regularity, period and amplitude ofthese stars. Most have well-defined periods in the 20 to 200 day range.Several also have a long secondary period. One (W Boo) appears to havetwo periods with a ratio of 2.3. (SECTION: Stars)
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Datos observacionales y astrométricos
| Constelación: | Boyero |
| Ascensión Recta: | 15h46m53.81s |
| Declinación: | +46°59'10.5" |
| Magnitud Aparente: | 7.201 |
| Distancia: | 36.337 parsecs |
| Movimiento Propio en Ascensión Recta: | -107.6 |
| Movimiento Propio en Declinación: | 5.4 |
| B-T magnitude: | 8.132 |
| V-T magnitude: | 7.278 |
Catálogos y designaciones:
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