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Is RY For an eclipsing binary? Was it an eclipsing binary? Although the GCVS lists it as an EB/SD: with a range 12.23 - 13.40 in B and a period of 0.4855 d., something is wrong with all these values. The V mag at maximum is well-known: V= 9.95. This would mean a very red star of B-V 2.28 at maximum. b-y colour is 0.91, this is ~1.5 for B-V. The 1971 edition of the GCVS lists: EB 11.0 - 12.2p. Is the variability range in B in the latest GCVS an error? Wolf and Kern (ApJS 52, 429, 1983) give 3 measures with no eclipses detected at the expected phases using the GCVS ephemeris (HJD 2427424.195 + 0.4855 x E) V is 9.95-9.96. They concluded that the ephemeris should be revised. ASAS-3 data (Pojmanski, 2002, Acta Astronomica, 52, 397) show no eclipses too !! But it confirms the period !! This is very strange because the star was discovered as an eclipsing binary with more than a magnitude of amplitude and now we have a 0.03 mag. amplitude lightcurve with the same period (V= 9.95 - 9.98). Secondary minimum does not occur at phase 0.5 but around 0.6-0.7. More accurate photometry is needed though, because such a small amplitude is near the errors for ASAS-3 data. However, the variability and the period are very clearly seen. Did someone publish something about the secondary eclipse and the phase it occur(ed)? This reminds me of the V699 Cygni case. Read the AAVSO Eclipsing Binary Update # 10 and an article on it: http://vsnet.aavso.org/observing/programs/eb/ebupdate10.shtml Although the red color of this variable would suggest a small amplitude red variable, the period doesn't support that and the fact that it was discovered photographically and the same period of the current microvariability was derived, makes RY For a strong case for an eclipsing binary that became "just" a reflection variable. Any comments? Regards, Sebastian. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://vsnet.grisoft.com). Version: 6.0.502 / Virus Database: 300 - Release Date: 18/07/03
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